Chapter 1 Introduction

1.1 BackgroundPeople’s expectations of broadband coverage are increasing continually they expect to be able to access internet based services

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wherever they travel at ever faster speeds. This behavior is driven both by a desire to always be online and increased use of real time data applications and machine to machine applications. People are using an increasing range of devices to access not only mobile voice, but also mobile media and internet based services at home, in the office and beyond. This growth is further fed by the improving capabilities of devices like feature phones, smart phones, note books and laptops all of which consume increasing quantities of mobile bandwidth. In addition, there is growing demand for fixed broadband delivered over cellular networks, especially in regions without wire line infra-structure. It is often assumed that take up of mobile broadband is driven by people living in towns and cities in developed markets, and to some extent this is true. But this reality often obscures another important aspect of the attractiveness of mobile broadband: its potential in rural and remote areas to offer significantly better wide-area broadband coverage than any competing technology. An important trigger for purchasing a mobile broadband service is wide area coverage the service can be used practically everywhere. The mobile broadband subscription is often registered at a city address, even when the purchase is triggered by the need for rural broadband use. In undeveloped markets, the business case for rolling out mobile broadband coverage widely is even more compelling as there is often no fixed broadband access network available outside cities and large towns.In Europe an average of 93 percent of people have access to a high-speed connection, but in rural areas that number drops to an average of only 70 percent and in certain countries the number drops even more dramatically. Broadband delivered over cellular networks provides a cost effective way of serving people who are without a fixed high speed connection today. Good coverage and the mobility it enables is one of the key advantages that mobile operators are able to use in marketing campaigns to differentiate themselves from both fixed and mobile competitors. Good coverage is also an important factor in network tests performed by magazines and consumer organizations. This means

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it makes sense for operators to extend coverage at sites that even though they do not initially appear to provide an obvious business case will nonetheless increase traffic and boost revenue across the whole network. Fortunately for operators of reasonably well developed GSM networks that offer GPRS and EDGE mobile data, it is more obvious where this investment should be targeted. This was not so in the early days of GSM rollouts, when it was hard for operators to know in which areas they should build new sites. Now if the mobile data traffic on GPRS and EDGE is high at a specific site, this site is a natural candidate for deploying HSPA. Operators can even analyze all of the current end-user devices and detect the existence of HSPA potential, even when only EDGE is used. This allows an operator to make accurate predictions of HSPA traffic from day one of HSPA site installation. The rapid increase of smart phones and mobile internet devices (MIDs) in the market further strengthens the need for wide area coverage of HSPA as users will expect that their devices will work everywhere. Also, although EDGE today does support many popular internet applications like Facebook, it does not support all internet applications, including sites such as YouTube [1].1.2 Objectives of the project

The objectives of this project are as follows :to know about development to HSPA technology ,to study and understand the

HSPA-technology,and-to-compare-wireless-technologies. 1.3 Project Organization

The project is organized in the following manner, chapter one is an Introduction, chapter two is development to HSPA, chapter three is

a HSPA technology, chapter four is a comparison of wireless. chapter five a Case study, and chapter six is a Conclusion.

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Chapter 2 Development

to HSPA

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2.1 Global System for Mobile Communications (GSM) originally from (Group Special Mobile) is the most popular standard for mobile telephony systems in the world. It is a digital mobile telephone system that is widely used in Europe and other parts of the world. GSM uses a variation of Time Division Multiple Access (TDMA) and is the most widely used of the three digital wireless telephone technologies (TDMA, GSM and CDMA) GSM digitizes and compresses data, then sends it down a channel with two other streams of user data, each in its own time slot. It operates at either the 900 MHz or 1,800 MHz frequency band. The GSM Association, its promoting industry trade organization of mobile phone carriers and manufacturers, estimates that 80% of the global mobile market uses the standard. GSM is used by over 1.5 billion people across more than 212 countries and territories. Its ubiquity enables international roaming arrangements between mobile network operators, providing subscribers the use of their phones in many parts of the world. GSM differs from its predecessor technologies in that both signaling and speech channels are digital, and thus GSM is considered a second generation (2G) mobile phone system. This also facilitates the wide-spread implementation of data communication applications into the system. The ubiquity of implementation of the GSM (Global System Market) standard has been an advantage to both consumers, who may benefit from the ability to roam and switch carriers without replacing phones, and also to network operators, who can choose equipment from many GSM equipment vendors[4]. GSM also pioneered low-cost implementation of the short message service (SMS), also called text messaging, which has since been supported on other mobile phone standards as well. The standard includes a world wide emergency telephone number feature (112). Newer versions of the standard were backward-compatible with the original GSM system. Release '97 of the standard added packet data capabilities by means of General Packet Radio Service (GPRS). Release '99

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introduced higher speed data transmission using Enhanced Data Rates for GSM Evolution (EDGE).

Figure (2-1) GSM over IP system structure

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2.2-GSM-Services the standard collection of applications and features available to mobile phone subscribers all over the world. The GSM standards are defined by the 3GPP collaboration and implemented in hardware and software by equipment manufacturers and mobile phone operators. The common standard makes it possible to use the same phones with different companies' services, or even roam into different countries. GSM is the world's most dominant mobile phone standard. The design of the service is moderately complex because it must be able to locate a moving phone anywhere in the world, and accommodate the relatively small battery capacity, limited input/output capabilities, and weak radio transmitters on mobile devices. GSM supports a comprehensive set of supplementary services that complement and support the telephony and data services described above. They are all defined in GSM standards. A partial listing of supplementary services follows. Call forwarding. This service gives the subscriber the ability to forward incoming calls to another number if the called mobile unit is not reachable, if it is busy, if there is no reply, or if call forwarding is allowed unconditionally. Barring of Outgoing Calls. This service makes it possible for a mobile subscriber to prevent all outgoing calls.Barring of Incoming Calls This function allows the subscriber to prevent incoming calls. The following two conditions for incoming call barring exist: baring of all incoming calls and barring of incoming calls when roaming outside the home PLMN Advice of Charge (AoC).The AoC service provides the mobile subscriber with an estimate of the call charges .There are two types of AoC information: one that provides the subscriber with an estimate of the bill and one that can be used for immediate charging purposes AoC for data calls is provided on the basis of time measurements Call Hold. This service enables the subscriber to interrupt an ongoing call and then subsequently reestablish the call. The call hold service is only applicable to normal telephony Call Waiting. This service enables the mobile subscriber to be notified of an incoming call during a conversation. The subscriber

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can answer, reject, or ignore the incoming call.Call waiting is applicable to all GSM telecommunications services using a circuit-switched connection. The multiparty service enables a mobile subscriber to establish a multiparty conversation that is a simultaneous conversation between three and six subscribers. This service is only applicable to normal telephony. Calling Line Identification presentation/restriction. These services supply the called party with the integrated services digital network (ISDN) number of the calling party. The restriction service enables the calling party to restrict the presentation. The restriction overrides the presentation Closed User Groups (CUGs). CUGs are generally comparable to a PBX. They are a group of subscribers who are capable of only calling themselves and certain numbers. Explicit Call Transfer (ECT). This service allows a user who has two calls to connect these two calls together and release its connections to both other parties.

2.3-Technical-details GSM is a cellular network, which means that mobile phones connect to it by searching for cells in the immediate vicinity. There are five different cell sizes in a GSM network macro, micro, pico, femto and umbrella cells. The coverage area of each cell varies according to the implementation environment. Macro cells can be regarded as cells where the base station antenna is installed on a mast or a building above average roof top level. Micro cells are cells whose antenna height is under average roof top level; they are typically used in urban areas. Pico cells are small cells whose coverage diameter is a few dozen meters they are mainly used indoors. femto cells are cells designed for use in residential or small business environments and connect to the service provider’s network via a broadband internet connection. Umbrella cells are used to cover shadowed regions of smaller cells and fill in gaps in coverage between those cells. Cell horizontal radius varies depending on antenna height, antenna gain and propagation conditions from a couple of hundred meters to several tens of

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kilometers. The longest distance the GSM specification supports in practical use is 35 kilometers (22 mi). There are also several implementations of the concept of an extended cell,[11] where the cell radius could be double or even more,depending on the antenna system, the type of terrain and the timing advance.Indoor coverage is also supported by GSM and may be achieved by using an indoor pico cell base station, or an indoor repeater with distributed indoor antennas fed through power splitters, to deliver the radio signals from an antenna outdoors to the separate indoor distributed antenna system. These are typically deployed when a lot of call capacity is needed indoors; for example, in shopping centers or airports. However, this is not a prerequisite, since indoor coverage is also provided by in-building penetration of the radio signals from any nearby cell. The modulation used in GSM is Gaussian minimum-shift keying (GMSK), a kind of continuous-phase frequency shift keying. In GMSK, the signal to be modulated onto the carrier is first smoothed with a Gaussian low-pass filter prior to being fed to a frequency modulator, which greatly reduces the interference to neighboring channels adjacent-channel interference. 2.3.1-GSM-carrier-frequencies GSM networks operate in a number of different carrier frequency ranges (separated into GSM frequency ranges for 2G and UMTS frequency bands for 3G), with most 2G GSM networks operating in the 900 MHz or 1800 MHz bands. Where these bands were already allocated, the 850 MHz and 1900 MHz bands were used instead (for example in Canada and the United States). In rare cases the 400 and 450 MHz frequency bands are assigned in some countries because they were previously used for first-generation systems. Most 3G networks in Europe operate in the 2100 MHz frequency band. Regardless of the frequency selected by an operator it is divided into timeslots for individual phones to use. This allows eight full-rate or sixteen half-rate speech channels per radio frequency. These eight radio timeslots (or eight burst periods) are grouped into a TDMA frame. Half rate channels use alternate frames in the same time slot.The channel data rate for all 8channels

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is 270.833 kbit/s, and the frame duration is4.615 ms. The transmission power in the handset is limited to a maximum of 2 watts in GSM850/900 and 1watt in GSM1800/1900. 2.3.2-Voice-codecs GSM has used a variety of voice codec to squeeze 3.1 kHz audio into between 6.5 and 13 kbit/s. Originally, two codecs, named after the types of data channel they were allocated, were used, called Half Rate (6.5 kbit/s) and Full Rate (13 kbit/s). These used a system based upon linear predictive coding (LPC). In addition to being efficient with bitrates, these codecs also made it easier to identify more important parts of the audio, allowing the air interface layer to prioritize and better protect these parts of the signal.GSM was further enhanced in 1997 with the Enhanced Full Rate (EFR) codec, a 12.2 kbit/s codec that uses a full rate channel. Finally, with the development of UMTS, EFR was refracted into a variable-rate codec called AMR-Narrowband,which is high quality and robust against interference when used on full rate channels, and less robust but still relatively high quality when used in good radio-conditions-on-half-rate-channels . 2.3.3-Network-Structure of The network is structured into a number of discrete sections:The Base Station Subsystem (the base stations and their controllers). the Network and Switching Subsystem (the part of the network most similar to a fixed network).This is sometimes also just called the core network.The GPRS Core Network(the optional part which allows packet based Internet connections).The Operations support-system(OSS)-for-maintenance-network-shown-in-figure(2-2). 2.3.4-Subscriber-Identity-Module(SIM) One of the key features of GSM is the Subscriber Identity Module, commonly known as a SIM card. The SIM is a detachable smart card containing the user's subscription information and phone book. This allows the user to retain his or her information after switching handsets-Alternatively, the user can also change operators while retaining the handset simply by changing the SIM. Some operators will block this by allowing the phone to use only a

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single SIM, or only a SIM issued by them; this practice is known as SIM locking and is illegal in some countries[6].

Figure (2-2) The structure of a GSM network

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2.4-TheGSM-Network GSM provides recommendations not requirements.-The-GSM specification define the function and interface requirements in detail but do not address the hardware. The reason for this is to limit the designers as little as possible but still to make it possible for the operators to buy equipments from different supplies. The GSM network is divided into three major systems: the switching system(SS) the base station system (BSS), and the operation and support system(OSS). The main purpose of the GSM network is to facilitate easier access to cellular and satellite platforms across international lines. Using digital technology, it employs both speech and data channels in its system. At minimum these channels operate on the second generation (2G) network, but many use the third generation (3G) system to offer these services to clients. This enables the exchange of information at high-speed data rates via satellites and mobile cellular towers across networks and company lines. For example, a person in Tokyo can text message a person in Toronto via Japan's system, through networks in the countries between until it finally arrives on the intended recipient's mobile device in Canada. Creation of the GSM network occurred in 1982 with a meeting between high level communication experts at the European Conference of Postal and Telecommunications Administrations. Its original purpose was to address cellular infrastructure in Europe, but it quickly expanded to other nations. Many of the standards and operational procedures of the GSM network are published in annual journals. These help industry experts to streamline communications protocol from one system to another. In particular, the network has been essential in establishing worldwide access to emergency telephone services using the digits one-one-two (112), redirecting global phone traffic to emergency responders in a user's proximity. It also is responsible for establishing text message technology during the 1980s.The GSM digital network operates on different frequencies depending on the system used, whether 2G or 3G. Each frequency is then subdivided into different channels that allow for short

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bursts of digital information to be sent via the GSM connection. Networks in North America operate on different frequencies than those in Europe or Asia. Much of this has to do with the sheer volume of mobile phone use in certain parts of the world and the fact that Canada and the United States had already allocated certain frequencies for other uses.[11] shown in figure (2-3) Mobile Station (MS) The mobile telephone. The Switching System (SS)Home Location Register (HLR) A database which stores data about GSM subscribers, including the Individual Subscriber Authentication Key (Ki) for each Subscriber Identity Module (SIM) Mobile Services Switching Center (MSC) The network element which performs the telephony switching functions of the GSM network. The MSC is responsible for toll ticketing, network interfacing, common channel signaling. Visitor Location Register (VLR) A database which stores temporary information about roaming GSM subscribers. Authentication Center (AUC) A database which contains the International Mobile Subscriber Identity (IMSI) the Subscriber Authentication key(Ki),and the defined algorithms for encryption Equipment Identity Register (EIR) A database which contains information about the identity of mobile equipment in order to prevent calls from stolen, unauthorized, or defective mobile stations. The Base Station System (BSS)Base Station Controller (BSC) The network element which provides all the control functions and physical links between the MSC and BTS. The BSC provides functions such as handover, cell configuration data, and control of radio frequency (RF) power levels in Base Transceiver Stations. Base Transceiver Station (BTS) The network element which handles the radio interface to the mobile station. The BTS is the radio equipment (transceivers and antennas) needed to service each cell in the network. The Operation and Support System (OSS)Message Center (MXE) A network element which provides Short Message Service (SMS), voice mail, fax mail, email, and paging. Mobile Service Node (MSN) A network element which provides mobile intelligent network (IN) services Gateway Mobile Services Switching Center(GMSC) A network

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element used to interconnect two GSM networks.GSM Interworking Unit (GIWU) The network element which interfaces to various data networks.

Figure(2-3) GSM Network

From Advantages of GSM, is mature; this maturity means a more stable network with robust features. Less signal deterioration inside buildings. Ability to use repeaters. Talk time is generally

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higher in GSM phones due to the pulse nature of transmission.The availability of Subscriber Identity Modules allows users to switch networks and handsets at will.GSM covers virtually all parts of the world so international roaming is not a problem. the despite advantages This is Disadvantages of GSM, Pulse nature of TDMA transmission used in 2G interferes with some electronics specially certain audio amplifiers. Intellectual property is concentrated among a few industry participants, creating barriers to entry for new entrants and limiting competition among phone manufacturers.GSM has a fixed maximum cell site range of 35 km, which-is-imposed-by-technical-limitations[7].

2.5-Integrated-to-(GSM) This figure(2-4) shows how a GSM system can be upgraded to offer WCDMA services. This diagram shows that 2 or more GSM channels are typically removed, replaced, or upgraded to have WCDMA modulation and transmission capability.

Figure(2-4) GSM system upgrade to WCDMA

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Driving Forces of development from GSM to WCDMA:- Ever-Increasing Subscribers :With the rapid increase in the number of mobile subscribers, radio frequency resources and network capacities have been utilized to their maximum limits in some developed countries and regions. 3G networks employ the CDMA technology with much higher frequency efficiency than that of the 2G/2.5G technologies to solve the contradiction between the subscriber increase and limited radio frequency resources. From this point of view, 2G radio technologies will inevitably be replaced by 3G technologies. Development of Mobile Services: The development of information technologies and subscriber’s diversified and personalized demands require the mobile communication system to provide richer services such as multimedia and high-speed data services. But the 2G network mainly provides voice and bearer services with a low transmission rate and limited QoS, which cannot meet the requirements of multimedia, e-business and mobile IP services. 3G technology can bring up to 2 Mb/s access rate in a low speed or motionless environment and 384 kb/s in a high speed environment, so 3G can provide various and personalized services and evolve in the directions of multimedia, personalization, intelligent services and packetization. Market Competition Among Operators : Due to the decrease of the voice service profit margin, diversified and competitive services have to be developed in order to increase ARPU of carriers. In 2G systems, services are standardized, so it is very difficult to deploy new services offered by the third party and meet the diversified and personalized demands. In a 3G system, a service can be regarded as and realized by the combination of different service features that are reflected by different service capabilities of different bearer networks, which exactly represents the variety and flexibility of 3G-service creation. The carriers can only survive and thrive by fully utilizing the 3G platform to implement differentiated competition [12].

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2.6-Development-To Wideband Code-Division Multiple Access(WCDMA) In the mid 1980’s a second generation (2G) digital system known as the Global System for Mobile Communications (GSM) was introduced for mobile telephony.It significantly improved speech quality over the older analog-based systems and, as it was an international standard, enabled a single telephone number and mobile phone to be used by consumers around the world.It led to significantly improved connectivity and voice quality, as well as the introduction of a whole slew of new digital services like low-speed data. Proving to be very successful, GSM was officially adopted by the European Telecommunications Standardization Institute (ETSI) in 1991.The success of GSM spurred the demand for further development in mobile telephony, and put it on an evolutionary path to third generation (3G) technology.Along the way, that development path has included 2G technologies like Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA).TDMA is similar in nature to GSM and provides for a tripling of network capacity over the earlier AMPS analog system. In contrast, CDMA is based on the principles of spread spectrum communication. Access to it is provided via a system of digital coding.In 1997 a 2.5G system called the General Radio Packet Service (GPRS) was introduced to accommodate the growing demand for Internet applications. As opposed to the existing 2G systems, it offered higher data rates and Quality of Service (QoS) features for mobile users by dynamically allocating multiple channels.GPRS installs a packet switch network on top of the existing circuit switch network of GSM, without altering the radio interface.In 1999, the International Telecommunications Union (ITU) began evaluating and accepting proposals for 3G

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protocols in an effort to coordinate worldwide migration to 3G mobile networks. These proposals were known as International Mobile Telecommunication 2000 (IMT-2000). One of the most important IMT-2000 proposals to emerge was Universal Telecommunications Services (UMTS).While GPRS is considered the first step in enhancing the GSM core network in preparation for EDGE and 3G, WCDMA is a 3G technology according to the 3GPP standard. It is the digital access system for the UMTS for the UMTS network and is today considered one of the world’s leading 3G wireless standards. (Wideband Code-Division Multiple Access)WCDMA, an ITU standard derived from Code-Division Multiple Access (CDMA),is officially known as IMT-2000 direct spread.It is a third-generation (3G) mobile wireless technology that promises much higher data speeds to mobile and portable wireless devices. wcdma can support (mobile/portable) voice, images, data communications at up to 2 Mbps (local area access) or 384 Kbps (wide area access).The input signals are digitized and transmitted in coded, spread-spectrum mode over a broad range of frequencies A 5 MHz-wide carrier is used, compared with 200 KHz-wide carrier for narrowband CDMA[8]. WCDMA is an approved 3G technology which increases data transmission rates via the Code Division Multiplexing air interface, rather than the Time Division Multiplexing air interface of GSM systems. It supports very high-speed multimedia services such as full-motion video, Internet access and video conferencing.It can also easily handle bandwidth-intensive applications such as data and image transmission via the Internet.is a direct spreading technology, it spreads it transmissions over a wide, 5 MHz, carrier and can carry both voice and data simultaneously. in addition, WCDMA boasts increased capacity

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over EDGE for high-bandwidth applications and features which include, among other things, enhanced security, QoS multimedia

Figure(2-5) Evolution of cellular technologies

support, and reduced latency (Table2-1). WCDMA transmits on a pair of 5 MHz-wide radio channels, while CDMA2000 transmits on one or several pairs of 1.25 MHz radio channels. Though W-CDMA does use a direct sequence CDMA transmission technique like CDMA2000, it is not simply a wideband version of CDMA2000 and it differs in many aspects from CDMA2000. From an engineering point of view ,W-CDMA provides a different balance of trade-offs between cost, capacity, performance, and density; it also promises to achieve a benefit of reduced cost for video phone handsets.It has been developed into a complete set of

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specifications, a detailed protocol that defines how a mobile phone communicates with the tower, how signals are modulated, how data grams are structured, and system interfaces are specified allowing free competition on technology elements [6].

parameters WCDMABandwidth 5 MHzChip rate 3.84 Mcps

Power control frequency 1500 Hz up/downBase station synchroization Not needed

Cell search 3-step approach via primary, secondary search code and CPICH

Downlink pilot CDM common (CPICH)TDM dedicated (bits in DPCH)

User separation CDM/TDM (shared channel)2G interoperability GSM-UMTS handover (Multi-

mode terminals)

Table2-1 System performance for WCDMA

The figure(2-6) shows a simplified diagram of a WCDMA system.This diagram shows that the WCDMA system include various types of mobile communication devices (called user equipment UE)that communicate through base stations (node B) and a mobile swiching center (MSC) or data routing networks to connect to other mobile telephones,public telephones,or to the Internet via a core network(CN).This diagram shows that the WCDMA system is compatible with both the 5MHZ wide WCDMA radio channel and the narrow 200KHZ GSM channels. This also shows that the core network is essentially divided between voice system (circuit switching) and packet data (packet switching).

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Figure (2-6),simplified diagram of a WCDMA system

From WCDMA Basics: Unlike GSM and GPRS, which rely on the use of the TDMA protocol, WCDMA like CDMA allows all users to transmit at the same time and to share the same RF carrier.Each mobile user’s call is uniquely differentiated from other calls by a set of specialized codes added to the transmission. WCDMA base stations differ from some of the other CDMA systems in that they do not have to be in system-wide time synchronization, nor do they depend on a Global Positioning System (GPS) signal. Instead, they work by transmitting a sync signal along with the downlink signal. A downlink or forward link is defined as the RF signal transmitted from the base station to the subscriber mobile phone. It consists of the RF channel, scrambling

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code (one per sector), an orthogonal variable spreading factor (OVSF) channel for signaling (one per call), and one or more OVSF channels for data .It also contains the sync signals (P-SCH and S-SCH), which are independent of OVSF and scrambling codes. The RF signal transmitted from the mobile phone is referred to as the uplink or reverse channel.

Figure(2-7),WCDMA channel structure

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2.7-Technical-Features-For-(WCDMA) Radio channels are 5 MHz wide. Chip rate of 3.84 Mcps Supported mode of duplex: frequency division(FDD),Time Division(TDD) Employs coherent detection on both the uplink and downlink based on the use of pilot symbols and channels [2].Supports inter-cell asynchronous operation. Variable mission on a10ms frame basis. Multi code transmission. Adaptive power control based on SIR (Signal to Interference Ratio). Multi user detection and smart antennas can be used to increase capacity and coverage. Multiple types of handoff (or handover) between different cells including soft handoff, softer handoff and hard handoff.1:1 frequency reuse scheme[6].From advantages of WCDMA: each transmitter is assigned an identification code. This means that data from multiple transmitters can be carried over the same frequency in the same geographical area at the same time without interference or loss of signal strength. The system also uses power control. This adjusts the strength of the signal transmitted by each cell phone so that it reaches the nearest transmitter at the same strength, regardless of how far away the phone is. This avoids the transmitter receiving signals which are excessively strong or weak, which could limit the transmitter's efficiency. WCDMA can cope particularly well when there are many devices in one area. This makes it particularly suitable for densely populated areas such as some major Asian cities. The system is also well suited to the technical requirements presented by video calls. despite advantages this is disadvantage of WCDMA: are that it is not used throughout the entire world, which limits take-up of compatible handsets among people who travel internationally, and that it is a relatively complex system which can be expensive to introduce into a new market [10].

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2.14-Integral-part-of-(WCDMA) HSPA is that it is an integral part of WCDMA. Wide-area mobilecoverage can be provided with HSPA: it does not need any additional spectrum or carriers. Currently, WCDMA can provide simultaneous voice and data services (multi-services) to users on the same carrier. This also applies to HSPA, which means that spectrum can be used efficiently. WCDMA is evolving, and the first step is to improve the downlink using HSDPA. This greatly improves the end-user experience by increasing bit-rates to as much as 14 Mbit/s in the downlink, reducing latency and increasing system capacity up to five-fold. Further improvements are made with the introduction of Enhanced Uplink. This increases the bit-rate in the uplink to as much as 5.8 Mbit/s, reduces latency further and increases system capacity two-fold. Currently, WCDMA can provide voice and data services on the same carrier simultaneously. No new spectrum or carriers are needed to roll out HSPA in the network. With the advantages of HSPA, WCDMA will further enable operators to provide end-users with more advanced mobile/wireless broadband applications, with wide-area coverage and mobility[7].A further benefit of HSPA is greater system capacity. For the operator, this means reduced production cost per bit. HSPA increases capacity in several ways: Shared-channel transmission, which results in efficient use of available code and power resources in WCDMA. A shorter TTI, which reduces round-trip time and improves the tracking of fast channel variations. Link adaptation, which maximizes channel usage and enables the base station to operate close to maximum cell power. Fast scheduling, which prioritizes users with the most favorable channel conditions. Fast retransmission and soft-combining, which further increase capacity.16QAM which yields higher bit-rates Depending on the deployment scenario, the combined capacity gain over WCDMA 3GPP Release 99 is up to five-fold in the downlink and up to two-fold in the uplink.

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Chapter 3

HSPA technology

3.1Over-View One of the key success factors for the dominance of the GSM/WCDMA family is economy of scale. The volume advantage is beneficial for both handsets and infrastructure

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equipment and drives the manufacturing costs down. It also facilitates the necessary Research & Development efforts, required to maintain the competitive advantage for a standard, to be distributed over a large number of manufactured units. The GSM/WCDMA technology has continuously evolved to meet the needs of a changing world of ever more universal wireless communications. One network that delivers all services A WCDMA network is already from the start designed as a multi service network. This means that services for voice, Mobil TV, Mobile & Wireless broadband etc, can be supported by the same infrastructure. This gives large benefits for the operator, such as: maximum usage of capacity resources, low entry cost level/low risk and fast time to market for new services. Voice : End users demand a high quality voice service with wide-area coverage and full mobility. Only the WCDMA family offers this on a truly global level with an enormous variety of attractive end user devices. With the upcoming introduction of AMR wideband, speech quality and system capacity for voice will reach even higher levels. This facilitates a growth of minutes of use per subscriber and secures a firm foundation for the operator’s success. Video telephony : Interest is steadily increasing for this service now that more and more end users have support for this in their devices and discover that family members and colleagues also have it. High quality, wide-area coverage and a large penetration of capable devices are a must for video telephony growth and WCDMA networks have this. And Mobile TV :Inherent support for interactivity and on-demand content distribution are strong cards to play in the Mobile TV game. Today, a wide range of unicast mobile TV services are offered by more than 100 WCDMA operators around the globe. With the growing usage of these services, the demand for capacity will increase. HSPA has very efficient means to increase the capacity of the network. To handle distribution of TV services to large groups of end users simultaneously, a highly efficient TV broadcast functionality called MBMS is introduced in WCDMA networks [3].

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Figure (3-1)

Mobile Broadband & Wireless Broadband: An attractive broadband service offers data communication with high speeds in uplink and downlink, high system capacity, low latency and wide-area availability. WCDMA networks deliver all of this today, including full mobility for data. users on the move. In networks today, cell ranges of up to 200 km have been proven with measured speeds that exceed 2 Mbps at the cell edge. This enables mobile operators to offer wireless broadband services to large areas that are not economically viable with fixed broadband. HSPA support is available in all types of end user devices like telephones, PDAs, laptops, Fixed Wireless Terminals and embedded modules giving the economies of scale needed to have attractive end user offerings. WCDMA operators have the possibility to offer a wide range of data services reaching from wireless usage in homes and offices to truly mobile usage, all with one network. And there is a

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strong evolution path for HSPA to reach even higher peak speeds, more capacity and lower latency. High Speed Packet Access is the most widely deployed mobile broadband technology in the world today and will build upon the 3.8 billion connections with the GSM family of technologies. HSPA is the terminology used when both HSDPA (3GPP Release 5) and HSUPA (3GPP Release 6) technologies are deployed on a network. HSPA Evolved (HSPA+ in 3GPP Release 7 and beyond) is also part of the HSPA technology and extends an operator’s investment in the network before the next step to 3GPP Long Term Evolution (LTE, or 3GPP Release 8 and beyond).  HSPA builds on third generation (3G) UMTS/WCDMA and is strongly positioned as the leading mobile data technology for the foreseeable future. allows for HSPA networks capable of peak bit-rates of 14.4 Mbps.  The first networks using 64 QAM modulation and offering 21 Mbps are also in operation.  The use of higher order modulation schemes (from 16 QAM up to 64 QAM), along with MIMO technology, takes HSPA into ‘HSPA+’ or evolved HSPA such as developed in 3GPP Release 7. Propelling the strong growth is a strong selection of devices supporting HSPA. The GSMA reported that more than 1,343 HSPA devices were on the market from 135 suppliers as of 1Q 2009. Whereas HSDPA optimizes downlink performance, HSUPA uses the Enhanced Dedicated Channel (E-DCH) for a set of improvements that optimizes uplink performance. Networks and devices supporting HSUPA became available in 2007 and the combined improvements in the uplink and downlink are called HSPA. These improvements include higher throughputs, reduced latency and increased spectral efficiency. HSUPA (HSPA) is standardized in Release 6 and results in an approximated 85 percent increase in overall cell throughput on the uplink and more than 50 percent gain in user throughput. HSUPA also reduces packet delays, a significant benefit resulting in significantly improved application performance on HSPA networks. Typical HSPA downlink user achievable rates are 1 to 4 Mbps and typical user achievable HSPA uplink speeds are 500 kbps to 2 Mbps as of

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1Q 2009. Theoretical peak speeds are significantly higher at 14 Mbps on the downlink and 5.8 Mbps on the uplink in a 5 MHz channel. Beyond throughput enhancements, HSPA also significantly reduces latency. In optimized networks, latency will fall below 50 milliseconds (ms), relative to current HSDPA networks at 70 ms.  And with a later HSPA introduction of 2 ms Transmission Time Interval (TTI), latency will be as low as 30 ms. HSPA gives carriers an efficient mobile broadband technology that can evolve to HSPA+ to meet the advanced wireless needs of customers. To leverage operator investments in HSPA and enhance the quality of service across networks, standards body 3GPP finalized Release 7 and Release 8, which specify a series of enhancements to create HSPA+. Also, 3GPP is examining further specifications in Release 9. HSPA+ employs many of the techniques utilized for LTE.3.2-High Speed Packet Access(HSPA) is a collection of two mobile telephony protocols, High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA), that extends and improves the performance of existing WCDMA protocols. A further standard, Evolved HSPA (also known as HSPA+), was released late in 2008 with subsequent adoption worldwide into 2010. HSPA is a packet-based mobile telephony protocol used in 3G/3.5G UMTS radio networks to increase data capacity and speed up transfer rates. HSPA which evolved from the WCDMA standard, provides download speeds at least five times faster than earlier versions, allowing users of HSPA networks a broader selection of video and music downloads. HSPA data transfer speeds can go up to 1 Mbps. HSPA supports increased peak data rates of up to 14 Mbit/s in the downlink and 5.8 Mbit/s in the uplink. It also reduces latency and provides up to five times more system capacity in the downlink and up to twice as much system capacity in the uplink, reducing the production cost per bit compared to original WCDMA protocols. HSPA increases peak data rates and capacity in several ways. Shared-channel transmission, which results in efficient use of available code and

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power resources in WCDMA A shorter Transmission Time Interval (TTI), which reduces round-trip time and improves the tracking of fast channel variations Link adaptation, which maximizes channel usage and enables the base station to operate at close to maximum cell power Fast scheduling, which prioritizes users with the most favorable channel conditions Fast retransmission and soft-combining, which further increase capacity 16QAM (Quadrature Amplitude Modulation), which yields higher bit-rates By July 2010, HSPA had been commercially deployed by over 200 operators in more than 80 countries. Many HSPA rollouts can be achieved by a software upgrade to existing 3G networks, giving HSPA a head start over WiMax, which requires a dedicated network infrastructure. A rich variety of HSPA enabled devices - more than 1000 available by July 2010 - together with ease of use is leading to rising sales of HSPA-enabled mobiles and is helping to drive the adoption of HSPA. HSUPA is a relatively simple upgrade to HSDPA networks and does not necessitate the replacement of major pieces of infrastructure. As a result, operators can deploy HSUPA quickly and cost-effectively. HSPA benefits operators by making more efficient use of spectrum – up to three times more capacity than UMTS. This efficiency means that operators can easily and cost-effectively accommodate more users and services without having to buy additional spectrum just to keep up with growth. Also, it reduces operators' overhead costs, and thus, makes them better able to price their HSPA services at a point that is competitive yet profitable. HSPA is backward-compatible with UMTS, EDGE and GPRS. This design benefits customers when they travel to areas that have not yet been upgraded to HSPA, as their HSPA-enabled handsets and modems will still provide fast packet-data connections for international roaming. Because HSPA is backward-compatible, applications designed for UMTS also run on HSPA networks and devices, which benefits application developers as well as operators. HSPA benefits from the scope and scale of the GSM ecosystem of vendors. Vendors currently offer more than 1,300 models of HSPA

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devices at a variety of price points. Besides handsets and PC card modems, HSPA is also embedded in many laptops from major vendors such as Acer, Dell, Fujitsu Siemens, HP, Lenovo and Panasonic. HSPA operates at most GSM frequencies, enabling global roaming and affording a great amount of flexibility.  Infrastructure and devices are currently supported for UMTS-HSPA by a variety of vendors in the following frequencies: 850, 900, 1700, 1800, 1900, 2100 and 1700/2100 MHz and will also be supported for all future frequency bands including 700, 2500 and 2600 MHz as well as the 1500 MHz band in Japan and the 2300 MHz in the U.S, HSPA gives carriers an efficient mobile broadband technology that can evolve to HSPA+ to meet the advanced wireless needs of customers [5].

3.3-Application-for-HSPA Like EVDO, HSPA works similarly to the way your cell phone operates in that it relies on signal from a wireless tower rather than a physical connection like a phone line or cable. An HSPA modem (often generically referred to as an "aircard" or "Laptop Connect Card" from AT&T) receives the signal and allows you to connect to the internet - it's as simple as that! HSPA modems come in several formats: USB dongle, Express Card, and PCMCIA card and you can use them either directly in your computer OR in a 3G router. Of course, like your cell phone, the modem alone doesn't provide internet access - you must subscribe to the service from an HSPA provider. AT&T is the leading HSPA provider in the USA (T-Mobile's 3G network also uses HSPA, but their coverage area is so limited they are not a major player at this time) and they offer service for $60/month for 5GB of usage (overage charges apply after 5GB). For most people, 5GB is plenty of data for surfing the web, emailing, and the occassional YouTube video.There are countless reasons to use mobile broadband (EVDO or HSPA) and we have helped customers get set up for a huge variety of applications! Below are just a few common ways people use mobile broadband: Mobile applications: Cars, trucks, RV's,

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commercial service/fleet vehicles, shuttles, carpool/vanpool, transit (busses, trains, ferries), taxis/limos, private/commercial vessels . and Portable uses: Mobile work teams, trade shows, conferences, conventions, vacations, commute access, emergency response setup. And Fixed-location customers: Backup to cable/DSL/T-1, dial-up alternative, satellite alternative. And Fixed-location customers: Backup to cable/DSL/T-1, dial-up alternative, satellite alternative . All UMTS operators are deploying HSPA for two reasons low incremental cost and HSPA makes such efficient use of spectrum for data that it results in a much lower overall cost per megabyte of data delivered. Typical HSPA downlink user achievable rates are 1 to 4 Mbps and typical user achievable HSPA uplink speeds are 500 kbps to 2 Mbps as of 1Q 2009. Theoretical peak speeds are significantly higher at 14 Mbps on the downlink and 5.8 Mbps on the uplink in a 5 MHz channel. The roadmap of HSPA as defined by 3GPP in Release 5 and Release 6 is being commercially deployed today. The majority of HSPA networks in commercial service operate at the peak theoretical downlink rate of 3.6 Mbps, approximately 70 percent as of 2Q 2009, and the bulk of the remainder operator at 7.2 Mbps peak rate.

3.4-High-Speed-Downlink-Packet-Access-(HSDPA) HSDPA is an upgrade to UMTS/WCDMA. HSDPA increases the download speeds by up to 3.5 times, initially delivering typical user data rates of 550 to 800 kbps.  Improvements to the downlink, through HSDPA, were the first upgrade steps available to operators seeking to deploy mobile broadband services as a part of 3GPP Release 5. There is some confusion regarding the use of acronyms involving HSDPA, and its further evolution to High Speed Uplink Packet Access (HSUPA), as the terms are often used interchangeably along with the acronym HSPA which refers to the both HSDPA and HSUPA in their evolved state. HSDPA speeds are ideal for bandwidth-intensive applications, such as large file transfers, streaming multimedia and fast Web browsing. HSDPA also offers latency as low as 70 to 100 milliseconds (ms) making it

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ideal for real-time applications such as interactive gaming and delay-sensitive business applications such as Virtual Private Networks (VPNs). High Speed Downlink Packet Access is predominately a software upgrade to Release 99 of the UMTS standard. HSDPA has been commercially available since December 2005, when Cingular Wireless – now AT&T – launched the world's first large scale HSDPA service. There are more than 300 HSDPA networks commercially deployed or in various stages of deployment in more than 115 countries (May 2009). International roaming is available as the technology falls back on UMTS, EDGE and GPRS for the continuation of voice and data services. HSDPA usually requires only new software and base station channel cards, instead of necessitating the replacement of major pieces of infrastructure from UMTS and does not require additional spectrum for deployment. As a result, UMTS operators can deploy HSDPA quickly and cost-effectively. In fact most operators that deploy 3G UMTS are deploying an HSDPA-ready network[9]. HSDPA technology significantly improves the UMTS downlink performance through techniques, such as adaptive modulation and coding, hybrid ARQ (HARQ) and fast scheduling. On the receiving side, initial HSDPA User Equipment (UE) solutions were based on single antenna CDMA rake receiver structures, similar to Release 99 UMTS receiver structures. The corresponding minimum performance requirement for HSDPA rake receivers was specified in Release 5. While the single antenna rake receivers worked very well for conventional UMTS and met initial system needs for HSDPA, advanced receiving technologies were later used to achieve even higher HSDPA throughputs. To achieve this goal, 3GPP studied two applicable techniques (receive diversity and advanced receiver architectures) as well as their minimum performance improvement and has specified them in Release 6. HSDPA also benefits operators by making more efficient use of spectrum, up to three times more capacity than UMTS.

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Figure (3-2) HSDPA Operation

This efficiency means that operators can easily and cost-effectively accommodate more users and services without having to buy additional spectrum just to keep up with growth. That efficiency also reduces operators' overhead costs, and thus, makes them better able to price their services at a point that is competitive yet profitable. HSDPA is backward-compatible with UMTS, EDGE and GPRS. This design benefits customers when they travel to areas that have not yet been upgraded to HSDPA, as their HSDPA-enabled handsets and modems will still provide fast packet-data connections. This design also benefits operators and application

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developers because applications designed for UMTS also run on HSDPA networks and devices. HSDPA benefits from the scope and scale of the GSM ecosystem of vendors. HSDPA Operation: Each UE reports channel quality on HSDPCCH, and The Node B in figure (3-2) determines which and when each UE is to be served, The Node B informs the UE to be served via HS-SCCH. Then deliver the data to the UE via HSDSCH .and The UE sends feedback (ACK/NAK) back to Node B on HS-DPCCH. 3.5 High speed uplink packet access(HSUPA) HSUPA is an upgrade to UMTS-HSDPA that uses the Enhanced Dedicated Channel (E-DCH) to constitute a set of improvements to optimize uplink performance. These improvements include higher throughput, reduced latency and increased spectral efficiency. HSUPA was standardized in 3GPP Release 6 and combined with High Speed Downlink Packet Access (HSDPA), is commonly referred to as High Speed Packet Access (HSPA).  In other words, Release 5 HSDPA upgraded to Release 6 HSUPA is considered mobile broadband HSPA. HSUPA results in an approximated 85 percent increase in overall cell throughput on the uplink and an approximated 50 percent gain in user throughput. HSUPA also reduces packet delays. HSUPA improves HSDPA uplink speeds from 384 kbps to a peak theoretical network rate of 5.8 Mbps while providing 14 Mbps peak theoretical network rates on the downlink. Many operators initially launched HSPA at the peak rates of 3.6 Mbps, and have upgraded their networks to 7.2 Mbps. At the end of 2008, many notebooks were supporting HSPA at 7.2 Mbps downlink with 2 Mbps uplink, in addition to EDGE. In fact, more than 83 percent of UMTS-HSPA devices with speeds of 3.6 Mbps or higher also support EDGE technology (GSA, May 2009 survey). Today, typical HSPA downlink user achievable rates are 1 to 4 Mbps and typical user achievable HSPA uplink speeds are 500 kbps to 2 Mbps. Theoretical peak speeds are significantly higher at 14.4 Mbps on the downlink and 5.8 Mbps on the uplink in a 5 MHz channel. Further evolutions of the technology to HSPA+ will deliver peak throughput rates of 21 Mbps and later 42 Mbps

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through techniques such as dual-carriers and MIMO antenna systems. HSUPA was first commercially deployed by Mobilkom Austria in February 2007. As of May 2009, there were 77 commercial HSUPA networks with an additional 92 planned. It is expected that all UMTS networks will evolve to HSUPA-HSPA. HSUPA achieves its performance gains through the following approaches: An enhanced dedicated physical channel A short Transmission Time Interval (TTI), as low as 2 milliseconds (ms), which allows faster responses to changing radio conditions and error conditions Fast Node-B-based scheduling, which allows the base station to efficiently allocate radio resources Fast Hybrid Automatic Repeat reQuest (HARQ), which improves the efficiency of error processing. The combination of TTI, fast scheduling, and fast HARQ also serves to reduce latency, which can benefit many applications as much as improved throughput. HSUPA can operate with or without HSDPA on the downlink, though it is likely that most networks will use the two approaches together. The improved uplink mechanisms also translate to better coverage, and for rural deployments, larger cell sizes. HSUPA-HSPA is an upgrade to UMTS networks that usually requires only new software and base station channel cards, instead of necessitating the replacement of major pieces of infrastructure. As a result, operators can deploy HSPA quickly and cost-effectively. Vendors, 3G Americas and many analysts expect that virtually all of the operators who deploy UMTS will also choose to deploy HSPA and in fact, most new deployments are HSPA-ready today. HSPA also benefits operators by making more efficient use of spectrum: up to three times more capacity than UMTS. This efficiency means that operators can easily and cost-effectively accommodate more users and services without having to buy additional spectrum just to keep up with growth. That efficiency also reduces operators' overhead costs, and thus makes them better able to price their HSPA services at a point that is competitive yet profitable. HSPA is backward-compatible with UMTS, EDGE and GPRS. This design benefits customers when they travel to areas that haven't yet been upgraded to HSPA,

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as their HSPA-enabled handsets and modems will still provide fast packet-data connections. This design also benefits operators and application developers because applications designed for UMTS also run on HSPA networks. HSPA benefits from the scope and scale of the GSM ecosystem of vendors. Vendors currently offer more than 1,300 models of HSPA devices at a variety of price points. Besides handsets and PC card modems, HSPA is also embedded in many laptops. HSUPA Operation: The UE sends a Transmission Request to the Node B in figure (3.3) for getting Resources ,and The Node B responds to the UE with a Grant Assignment, allocating Uplink band to the UE, The UE uses the grant to select the appropriate transport format for the Data Transmission to the Node B, The Node B attempts to decode the received data and send ACK/NAK to the UE, In case of NAK, data may be retransmitted.

Figure (3-3) HSUPA Channel Operation.

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Table (3-1) Comparison Between HSUPA and HSDPA.

Figure (3.4) UMTS Data Rate Evolution.

Table (3-2) UMTS Data Rate Evolution.

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3.6-High-speed-packet-access-plus-(HSPA+) Nearly all WCDMA operators across both developed and developing countries have rapidly launched HSPA services to capitalize on its excellent mobile broadband capabilities and increased data capacity. The enhanced downlink (HSDPA) had been launched commercially by 217 operators in 93 countries as of early 2009.The enhanced uplink (HSUPA) is also quickly being introduced with around 50 deployments as of early 2009. HSPA devices have proliferated and mobile operators have seen data services account for a rising and substantive proportion of their revenue. HSPA+ is the natural evolution of HSPA and operators are now preparing to commercially launch HSPA+ R7 in early 2009.HSPA+ R7 is the first evolutionary step beyond HSPA and HSPA+ R8 is targeted for commercialization during 2010 with multicarrier as a key feature. HSPA+ further enhances the mobile broadband experience and increases the voice and data capacity of HSPA[1].

HSPA+ is also known as HSPA Evolution and Evolved HSPA. HSPA+  was standardized in 3GPP Release 7 and Release 8. HSPA+ will apply some of the techniques developed for Long Term Evolution (LTE) and allow operators to extend the life of their HSPA networks. 3G Americas initiated proposals at 3GPP to lead the development of the HSPA+ standards which now have received wide scale commitments from operators. HSPA+ will bring improved support and performance for real-time conversational and interactive services such as Push-to-Talk over Cellular (PoC), picture and video sharing, and Video and Voice over Internet Protocol (VoIP) through the introduction of features like Multiple-Input Multiple-Output (MIMO) antennas, Continuous Packet Connectivity (CPC) and Higher Order Modulations. the Some of the key features of HSPA+ include the: HSPA+ is a simple upgrade to today’s HSPA networks, protecting

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an operator’s investment in the network. HSPA+ enhancements are backward-compatible with UMTS Release 99/Release 5/Release 6. HSPA+ provides a strategic performance roadmap advantage for incumbent GSM-HSPA operators providing OFDMA-equivalent performance in 5X5 MHz spectrum allocations with only incremental investment. HSPA+ could match, and possibly exceed, the potential performance capabilities of IEEE 802.16e-2005 (mobile WiMAX) in the same amount of spectrum, and could match LTE performance when using 5 MHz of spectrum. And HSPA+ will significantly increase HSPA capacity as well as reduce latency below 50 milliseconds (ms). The first phase of HSPA+ with 64 QAM has already been deployed commercially and is providing peak theoretical downlink throughput rates of 21 Mbps. HSPA+ with 64 QAM and advanced antenna techniques such as 2X2 MIMO can deliver 42 Mbps theoretical capability and 11.5 Mbps on the uplink and could be ready for deployment in 2010. Smooth interworking will be provided between HSPA+ and LTE that facilitates operation of both technologies. As such, operators may choose to leverage the System Architecture Evolution/Evolved Packet Core (SAE/EPC) planned for LTE. HSPA+ supports voice and data services on the same carrier and across all of the available radio spectrum and offers these services simultaneously to users HSPA+ is an affordable and incremental upgrade to existing HSPA networks. It provides a tremendous advantage to HSPA operators, which is not an option for CDMA operators who are already unable to compete with the higher data throughput performance of HSPA and have no future evolution commercially viable for enhancement to their EV-DO  networks today. Because it offers impressive performance at an incremental cost, some HSPA operators plan to use HSPA+ as a companion to LTE.  Telstra in Australia, Starhub in Singapore, CSL in Hong Kong and Mobilkom Austria in Central and Eastern Europe were the first operators to launch commercial HSPA+ networks in early 2009, initially providing peak theoretical download speeds of 21 Mbps. Several operators such as Telstra plan to upgrade their

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network-to-42-Mbps-in-the-short-term. HSPA+ is the name of the set of HSPA enhancements that are defined in 3GPP beyond Release 6 (R6). The enhanced downlink (HSDPA) was defined in R5 and the enhanced uplink (HSUPA) was defined in R6. HSPA+ is the natural and most economical evolution from HSPA ,allowing WCDMA/HSPA operators to make the most efficient use of their existing assets and investments in network, spectrum and devices at a lower cost. HSPA+ is backward compatible, allowing for a gradual introduction of devices and a smooth, cost-efficient and simple network upgrade to existing HSPA nodes. Thanks to the doubled data capacity and more than doubled voice capacity over HSPA and WCDMA, respectively, HSPA+ enables operators to offer mobile broadband and voice services at an even lower cost. HSPA+ further enhances the end user experience through lower latency, extended talk time through VoIP, and an improved “always-on” experience. Given the availability of HSPA+ R7 in early 2009, HSPA+ and its evolution remains the most optimal solution for existing WCDMA/HSPA operators. HSPA+ provides a proven technology with economies of scale in device and network procurement. HSPA+ has a strong evolution path; HSPA+ Release 8 (R8) is targeted for commercialization during 2010 and introduces the first step of the multicarrier feature which further enhances the broadband experience by doubling the user data rates to all users. HSPA+ is therefore the optimal solution for single or aggregated 5 MHz carriers and provides similar performance as LTE in the same bandwidth and when using the same number of antennas.[6]

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Figure (3-5) Development Of HSPA During The Four Years.

HSPA and HSPA+ allows consumers and business users to rely on HSPA as their main broadband connection, and offer a similar user experience across mobile and fixed networks. HSPA’s high capacity broadband uplink and downlink with integrated QoS and low latency can support the entire range of IP services, including delay-sensitive applications such as VoIP and low latency gaming. HSPA+ further enhances the user’s experience and makes these services more affordable by lowering costs through increased capacity.HSPA+ Doubles Data Capacity and Reduces Cost:With the launch of HSPA, operators are seeing a significant uptake in data demand,

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a result of new data applications and increased demand for high-performance mobile broadband services. HSPA+ enhances the performance of HSPA networks and enables wireless operators to continue to fulfill these data needs in the most economical way, as HSPA+ doubles the data capacity compared to HSPA R6. Figure(3-6) compares the downlink and uplink data capacity of HSPA and HSPA+. The almost doubled downlink and uplink data capacity assumes advanced receivers (UE equalizer, device receive diversity and Node B IC)1 in addition to the HSPA+ features.

Figure(3-6) Data Capacity per Sector in Mbps (5 MHz).

HSPA greatly increased data capacity over R99 systems by adding the high-speed shared channels with HOM (16QAM), smaller transmission interval, Hybrid ARQ (HARQ) and opportunistic scheduling. HSPA+ builds on this solid foundation by adding support for 64QAM, 2x2 MIMO, DTX/DRX and other air interface improvements to enhance the capacity and the user experience.HSPA+ More than Doubles the Voice Capacity: High-quality voice is a key service that has traditionally been the core of the wireless business. HSPA+ enables two options, CS (circuit-

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switched) voice over HSPA or VoIP, which both more than double the WCDMA R99 voice capacity and provide up to 50% more talk time, while maintaining the same quality and codec. Users will continue to enjoy simultaneous voice and high-speed data services while operators now can flexibly mix voice and data services on the same HSPA+ carrier. Figure (3-7) shows the voice over HSPA options and the more than doubled voice capacity over WCDMA.

Figure (3-7) Voice over HSPA more than doubles voice capacity over WCDMA.

CS voice over HSPA leaves the core network intact, allowing operators to leverage their existing core network investments, while VoIP relies on the IMS core network. CS voice over HSPA is therefore the natural upgrade for most operators but could also be an intermediate step toward the long-term goal to migrate to VoIP. In current WCDMA/HSPA networks, voice services are carried over dedicated CS bearers, which are assigned to users for the duration of the voice call. Voice over HSPA uses the shared-packet channels with smaller transmission intervals and HARQ to

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transfer-voice-packets-more-efficiently. HSPA+ further improves voice capacity by introducing enhancements such as CPC. This optimizes air-interface resource usage, providing almost double the voice capacity without Node B IC and an almost threefold increase with Node B IC. The enhanced serving cell change (E-SCC) in R8 further improves the handover reliability with reduced dropped calls in demanding propagation environments. It also enables full voice over HSPA capacity potential by allowing the use of F-DPCH in all propagation scenarios.HSPA+ is the natural evolution of HSPA at a lower cost: provides an excellent technology evolution path from HSPA enabling operators to maximize their return on existing investments with commercial deployments starting in early 2009. HSPA+ is designed to be compatible with existing R99, R5/R6 devices and networks, and uses the same spectrum and network resources to deliver enhanced performance. The existing radio and core network can be upgraded to HSPA+ without the need for adding any new network elements. Existing WCDMA and new HSPA+ devices can roam seamlessly between WCDMA, HSPA and HSPA+ networks. Backward compatibility will enable operators to roll out HSPA+ features in phases, without concern about device/network incompatibility. Many of the HSPA+ features are software upgrades to the existing base stations. By deploying HSPA+, wireless operators will benefit tremendously from the vast 3GPP device and vendor ecosystem that provides economies of scale benefits to the 3GPP community. Operators have greater flexibility in selecting vendors, and have a larger choice of devices and terminals that they can potentially offer to their customers at an affordable price. This wide vendor support and backward compatibility also enables operators to deploy HSPA+ in a timely manner and gives them a time to- market advantage compared with other competing technologies.[8]

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Figure(3-8) The Development Of HSPA+ Network and Upgrade.

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CHAPTER 4

Comparison of Wireless

Technologies

4.1 Comparison of Wireless TechnologiesThis the chapter compares the different wireless technologies, looking at throughput, latency, spectral efficiency, and market position. Finally, the chapter presents a table that summarizes the competitive position of the different technologies across multiple dimensions.4.2-Data-Throughput Data throughput is an important metric for quantifying network throughput performance. Unfortunately, the ways in which various organizations quote throughput statistics vary tremendously, which

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often results in misleading claims. The intent of this chapter is to realistically represent the capabilities of these technologies. One method of representing a technology’s throughput is what people call “peak throughput” or “peak network speed.” This refers to the fastest possible transmission speed over the radio link, and it is generally based on the highest order modulation available and the least amount of coding (error correction) overhead. Peak network speed is also usually quoted at layer 2 of the radio link. Because of protocol overhead, actual application throughput may be 10 to 20 percent lower (or more) than this layer 2 value. Even if the radio network can deliver this speed, other aspects of the network such as the backhaul from base station to operator-infrastructure network can often constrain throughput rates to levels below the radio-link rate. Another method is to disclose throughputs actually measured in deployed networks with applications such as File Transfer Protocol (FTP)under favorable conditions, which assume light network loading(as low one active data user in the cell sector) and favorable signal propagation This number is useful because it demonstrates the high end actual capability of the technology. This refers to this rate as the “peak user achievable rate.” average rates are lower than this peak rate, and no precise guideline can be provided. Unless the network is experiencing congestion, the majority of users should experience throughput rates higher than one-half of the peak achievable rate.Table 4-1 presents the technologies in terms of peak network throughput rates and peak user-achievable rates (under favorable conditions). It omits values that are not yet known, such as those associated with future technologies[12].

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Table(4-1) Throughput Performance of Different Wireless

Technologies(Blue Indicates Theoretical Peak Rates)

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Yet another approach to representing a technology’s throughput is to quote an average or typical speed for users that takes more factors into account, such as the operator’s actual network configuration, backhaul constraints, and a higher though generally unspecified level of loading. U.S.operators have quoted typical throughput rates, but this is less common in other countries. Actual results from operator and vendor field trials matched these predicted results, validating the methodology used to predict performance. 4.3 HSDPA Throughput in Representative ScenariosIt is instructive to look at actual HSDPA throughput in commercial networks.Figure (4-1) shows the downlink throughput performance of a 7.2 Mbps device. It results in a median throughput of 1.9 Mbps when mobile, 1.8 Mbps with poor coverage, and 3.8 Mbps with good coverage.

Figure(4-1) HSDPA Performance of a 7.2 Mbps Device in a Commercial Network

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Figure (4-2), Figure (4-3) and Figure (4-4) show earlier test results from a network in Europe with a light data load but supporting voice traffic. Neither the median value nor the actual histogram should be taken as absolute. Rather,the distribution shows representative HSDPA performance. Actual performance will vary by network, geography, network load, devices, and so forth. However, distributions will generally have these kinds of profiles, and the performance is relatively typical of HSDPA on today’s networks. Under a favorable signal condition with a1.8Mbps device,the-median-bit-rate-measured-was1.48Mbps. The blue line in Figure(4-2) is the Cumulative Distribution Function (CDF),which shows the probability of throughput being at least that high[14].

Figure(4-2) Histogram of HSDPA Throughput Under Favorable Radio Condition

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Figure (4-3)shows the distribution of throughput under unfavorable radio conditions. Though measured values were lower than those under good radio conditions, the median rate was still quite high, at 930 kbps.

Figure(4-3) Histogram of HSDPA Throughput Under Unfavorable Radio Conditions

Figure (4-4) shows the distribution of throughput measured with favorable radio conditions while driving through a coverage area. Though lower than stationary operation throughput, the median throughput rate was still 1.2 Mbps. It is interesting to note how the range of data rates experienced by a user increases when moving

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from an area with favorable conditions to areas with less favorable conditions or when in a mobile environment.

Figure(4-4): Histogram of HSDPA Throughput Under Favorable Radio Conditions While Mobile

4.4 Release 99 and HSUPA Uplink PerformanceHSUPA will dramatically increase uplink throughputs over 3GPP Release99.However, even Release 99 networks have seen significant uplink increases. Many networks were initially deployed with a 64 kbps uplink rate. this increased to 128 kbps. Now, operators have increased speeds further, to 384 kbps peak rates, with peak user achievable rates of 350 kbps. Figure (4-5), under conservative assumptions, shows the average throughputs

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when using a Release 99 128 kbps Bearer or a Release 99 384 kbps Bearer and when using HSUPA in a system limited to 1.46 Mbps maximum throughput. It plots throughputs versus cell range and shows operation at 1900 MHz in a suburban area with 10 simultaneous-voice-users[13]. The cell range is only one of the dimensions that can affect the average throughput. Similar to HSDPA, the fast scheduling and Automatic Repeat Request (ARQ) used in HSUPA allow the system to adjust the instantaneous data rate to the instantaneous propagation and interference conditions faced by the terminal. Figure (4-5) also shows that average throughput of more than 500 kbps is achievable at 1900 MHz in a suburban area for a typical inter-site distance of 2.5 kilometers (1.7 km max cell range), but it will be lower for higher inter-site distances.

Figure(4-5) Average Release 99 Uplink and HSUPA Throughput

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The anticipated 1 Mbps achievable uplink throughput can be seen in the measured throughput of a commercial network, as documented in Figure (4.6).

Figure(4.6) Uplink Throughput in a Commercial Network

Latency Just as important as throughput is network latency, defined as the round-trip time it takes data to traverse the network. Each successive data technology from GPRS forward reduces latency, with HSDPA having latency as low as 70 milliseconds (msec). HSUPA brings latency down even further, as will 3GPP

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LTE. Ongoing improvements in each technology mean all these values will go down as vendors and operators fine-tune theirsystems.Figure (4-7) shows the latency of different 3GPP technologies.

Figure(4-7) Latency of Different Technologies

The values shown in Figure 4.7 reflect measurements of commercially deployed technologies. Some vendors have reported significantly lower values in networks using their equipment, such as 150 msec for EDGE, 70 msec for HSDPA, and 50 msec for HSPA. With further refinements and the use of 2 msec Transmission Time Interval (TTI) in the HSPA uplink, 25 msec roundtrip is a realistic goal. LTE will reduce latency even further, to as low as 5 msec in the radio-access network.

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4.5 Spectral EfficiencyTo better understand the reasons for deploying the different data technologies and to better predict the evolution of capability, it is useful to examine spectral efficiency.The evolution of data services will be characterized by an increasing number of users with ever-higher bandwidth demands. As the wireless-data market grows, deploying wireless technologies with high spectral efficiency will be of paramount importance. Keeping all other things equal, such as frequency band, amount of spectrum, and cell site spacing, an increase in spectral efficiency translates to a proportional increase in the number of users supported at the same load per user or, for the same number of users, an increase in throughput available to each user. Delivering broadband services to large numbers of users can be best achieved with high spectral efficiency systems, especially because the only other alternatives are using more spectrum or deploying more cell sites. However, increased spectral efficiency comes at a price. It generally implies greater complexity for both user and base station equipment. Complexity can arise from the increased number of calculations performed to process signals or from additional radio components. Hence, operators and vendors must balance market needs against network and equipment costs. One core aspect of evolving wireless technology is managing the complexity associated with achieving higher spectral efficiency. The reason technologies such as OFDMA are attractive is that they allow higher spectral efficiency with lower overall complexity; hence their use in technologies such as LTE, UMB, and WiMAX. The roadmap for the EDGE/HSPA/LTE family of technologies provides a wide portfolio of options to increase spectral efficiency. The exact timing for deploying these options is difficult to predict, because much will depend on the growth of the wireless data market and what types of applications become popular. When determining the best area on which to focus future technology enhancements, it is interesting to note that HSDPA, 1xEV-DO, and IEEE 802.16e-2005 all have highly optimized links that is, physical layers. In

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fact, as shown in Figure4.8, the link layer performance of these technologies is approaching the theoretical limits as defined by the Shannon bound. (The Shannon bound is a theoretical limit to the information transferrate [per unit bandwidth] that can be supported by any communications link. The bound is a function of the Signal to Noise Ratio [SNR] of the communications link.) Figure 4.8 also shows that HSDPA, 1xEV-DO, and IEEE 802.16e-2005 are all within 2 to 3 decibels (dB) of the Shannon bound, indicating that there is not much room for improvement from a link layer perspective[15].

Figure(4-8): Performance Relative to Theoretical Limitsfor HSPDA, EV-DO, and IEEE 802.16e-2005

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The curves in Figure (4-8) apply to an Additive White Gaussian Noise Channel (AWGN). If the channel is slowly varying and the effect of frequency selectivity can be overcome through an equalizer in either HSDPA or OFDM, then the channel can be known almost perfectly and the effects of fading and non-AWGN interference can be ignored thus justifying the AWGN assumption. For instance, at 3 km per hour, and fading at 2 GHz, the Doppler spread is about 5.5 Hz. The coherence time of the channel is thus 1 sec/5.5 or 180 msec. Frames are well within the coherence time of the channel, because they are typically 20 msec or less. As such, the channel appears “constant” over a frame and the Shannon bound applies. Much more of the traffic in a cellular system is at slow speeds (for example,3 km/hr) rather than at higher speeds. Thus, the Shannon bound is relevant for a realistic deployment environment. As the speed of the mobile station increases and the channel estimation becomes less accurate, additional margin is needed. this additional margin would impact the different standards fairly equally. The Shannon bound only applies to a single user; it does not attempt to indicate aggregate channel throughput with multiple users. it does indicate that link layer performance is reaching theoretical limits. As such, the focus of future technology enhancements should be on improving system performance aspects that maximize the experienced SNRs in the system rather than on investigating new air interfaces that attempt to improve the link layer performance. Examples of technologies that improve SNR in the system are those that minimize interference through intelligent antennas or interference coordination between sectors and cells. Note that MIMO techniques using spatial multiplexing to potentially increase the overall information transfer rate by a factor proportional to the number of transmit or receive antennas do not violate the Shannon bound, because the per antenna transfer rate (that is, the per communications link transfer rate) is still limited by the Shannon bound. Figure (4-9) compares the spectral efficiency of different wireless technologies It shows the

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continuing evolution of the capabilities of all the technologies discussed. The values shown are conservative and intended to be reasonably representative of real-world conditions. Most simulation results produce values under idealized conditions; as such, some of the values shown are lower (for all technologies) than the values indicated in other papers and publications. For instance, 3GPP studies indicate higher HSDPA and LTE spectral efficiencies than those shown below:

Figure(4-9) Comparison of Downlink Spectral Efficiency

The values shown in Figure(4-9) are not all the combinations of available features. Rather, they are representative milestones in ongoing improvements in spectral efficiency. For instance, there

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are terminals that employ mobile-receive diversity but not equalization. Relative to WCDMA Release 99, HSDPA increases capacity by almost a factor of three. Type 3 receivers that include Minimum Mean Square Error (MMSE) equalization and Mobile Receive Diversity (MRxD) will effectively double HSDPA spectral efficiency. HSPA+ in Release 7 includes 2X2 MIMO, which further increases spectral efficiency by about 20 percent and matches WiMAX Wave 2 spectral efficiency. Methods such as successive interference cancellation (SIC) and 64 QAM allow gains in spectral efficiency as high as 1.3 bps/Hz, which is close to LTE performance in 5+5 MHz. Terminals with SIC can also be used with Release 7 systems. Beyond HSPA, 3GPP LTE will also result in further spectral efficiency gains, initially with 2X2 MIMO and then optionally with 4X2 and 4X4 MIMO. LTE becomes more spectrally[13] efficient with wider channels, such as 10 and 20 MHz. Similar gains are available for CDMA2000. Mobile WiMAX also experiences gains in spectral efficiency as various optimizations, like MRxD and MIMO, are applied. WiMAX Wave 2 includes 2X2 MIMO. Enhancements to WiMAX will come from potentially new profiles, as well as a new version of the standard IEE 802.16m which likely will match LTE and UMB spectral efficiency.The main reason that HSPA+ with MIMO is shown as spectrally more efficient than WiMAX with MIMO is because HSPA MIMO supports closed-loop operation with precode weighting and multi code word MIMO, which enables the use of SIC receivers. Other reasons are that HSPA supports incremental-redundancy HARQ, while the initial WiMAX profiles support only Chase combining HARQ, and that WiMAX has larger control overhead in the downlink than HSPA, because the uplink in WiMAX-is-fully-scheduled. OFDMA technology requires scheduling to avoid two mobile devices transmitting on the same tones simultaneously. An uplink MAP zone in the downlink channel does this scheduling. Conversely, HSUPA can use autonomous transmission on the uplink. Hence, there is no downlink overhead required to schedule

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the uplink. This leads to a disadvantage for HSUPA in the uplink when compared to WiMAX, as Figure(4-10) shows, because the HSUPA uplink is not orthogonal. But autonomous transmission does provide the advantage of lower downlink control overhead for HSPA relative to WiMAX. It also helps to mitigate other-cell interference, which may become a problem when WiMAX is deployed.LTE also has higher spectral efficiency than WiMAX, because it includes incremental redundancy and supports closed-loop operation with precoder weighting as well as multicode word MIMO, thus enabling the use of SIC receivers. An important conclusion of this comparison is that all the major wireless technologies achieve comparable spectral efficiency through the use of comparable radio techniques.Figure (4-10)compares the uplink spectral efficiency of the different systems.

Figure(4-10) Comparison of Uplink Spectral Efficiency

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HSUPA significantly increases uplink capacity, as does Rev A of 1xEV-DO, compared to Rev 0. OFDM-based systems can exhibit improved uplink capacity relative to CDMA technologies, but this improvement depends on factors such as the scheduling efficiency and the exact deployment scenario. Figure (4-10) shows WiMAX uplink spectral efficiency to be lower than 3GPP and 3GPP2 technologies employing interference cancellation. This is because of the high pilot overhead in IEEE 802.16e, which accounts for up to 33 percent of tones. With the optional but more efficient pilot structure implemented, it is likely that IEEE 802.16e uplink spectral efficiency will be on par. Opportunities will arise to improve voice capacity using VoIP over HSPA channels. Depending on the specific enhancements implemented, voice capacity could double over existing circuit-switched systems. It should be noted, however, that the gains are not related specifically to the use of VoIP; rather, gains relate to advances in radio techniques applied to the data channels. Many of these same advances could also be applied to current circuit-switched modes. However, other benefits of VoIP are driving the migration to packet voice. Among these benefits are a consolidated IP core network for operators and sophisticated multimedia applications for users. Figure (4-11) compares voice spectral efficiency. It assumes a round-robin type of scheduler, as opposed to a proportional-fair scheduler that is normally used for asynchronous data.

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Figure(4-11) Comparison of Voice Spectral Efficiency

EV-DO technologies could possibly exhibit a slightly higher spectral efficiency for VoIP than HSPA technologies (though not for packet data in general), as they operate purely in the packet domain and do not have circuit-switched control overhead. HSPA has a significant advantage of being able to support simultaneous circuit-switched and packet-switched users on the same radio channel. Initial versions of VoIP with IEEE 802.16e are not expected to be nearly as spectrally efficient as current circuit-switched approaches with CDMA-based systems, though future versions of WiMAX will become more efficient in this regard.

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4.6 Cost and Volume Comparisoncompared wireless technologies on the basis of technical capability and demonstrated that many of the different options have similar technical attributes. This is for the simple reason that they employ many of the same approaches. there is a point of comparison where the differences between the technologies diverge tremendously; namely, the difference in volume involved, including subscribersand the amount of infrastructure required. This difference should translate to dramatically reduced costs for the highest volume solutions, specifically GSM/UMTS. Based on projections and numbers already presented,3G subscribers on UMTS networks will number in the many hundreds of millions by the end of this decade, whereas subscribers to emerging wireless technologies such as IEEE 802.16e-2005 will number in the tens of millions. See Figure(4-12) for details. Although proponents for technologies such as mobile WiMAX point to lower costs for their alternatives, there doesn’t seem to be any inherent cost advantage even on an equal volume basis. And when factoring in the lower volumes, any real-world cost advantage is debatable. From a deployment point of view, the type of technology used (for example, HSPA versus WiMAX) only applies to the digital card at the base station. the cost of the digital card is only a small fraction of the base station cost, with the remainder covering antennas, power amplifiers, cables, racks, RF cards, and digital cards. As for the rest of the network, including construction, backhaul, and core-network components, costs are similar regardless of Radio Access Network (RAN) technology.

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Figure(4-12): Relative Volume of Subscribers Across Wireless Technologies

Spectrum costs for each technology can differ greatly, depending on a country’s regulations and then spectrum band. As a general rule in most parts of the world, spectrum sold at 3.5 GHz will cost much less than spectrum sold at 850 MHz (all other things being equal).The advantages of high volume can be seen in projections for GSM handsets. amortization results in a four-to-one difference in base station costs. just as GSM handsets are considered much less expensive than 1xRTT handsets, UMTS wholesale terminal prices could be the market leader in low-cost or mass-market 3Gterminals. Developments such as single-chip UMTS complementary metal oxide semiconductor (CMOS) transceivers

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could be particularly effective in making UMTS/HSDPA devices more affordable to the mass market.On the heels of the success of the GSM low-cost handset program, GSMA in early 2007 announced the winner of its “3G for All” program, in which eight handset vendors submitted 19 mass-market 3G device prototypes for consideration by 12 leading GSM operators. The winner, LGKU250,is possibly the lowest cost UMTS device and is now available in many of the world’s markets.Table(4-2) summarizes the competitive position of the different technologies discussed.

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Table(4-2) Competitive Position of Major Wireless Technologies

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The EDGE/HSPA/LTE family of technologies provides operators and subscribers a true mobile-broadband advantage. The continued use of GSM and EDGE technology through ongoing enhancements allows operators to leverage existing investments.With UMTS/HSPA, the technologies advantages provide for broadband services that will deliver increased data revenue and provide a path to all-IP architectures. With LTE, the advantages offer a best of breed long-term solution that matches or exceeds the performance of competing approaches. In all cases, the different radio access technologies can coexist using the same core architecture. Today, HSDPA offers the highest peak data rates of any widely available wide-area wireless technology. With continued evolution, peak data rates will continue to increase, spectral efficiency will increase, and latency will decrease. The result is support for more users at higher speeds with more applications enabled. Application scope will also increase, with QoS control and multimedia support through systems such as IMS. Greater efficiencies will translate to more competitive offers, greater network usage, and increased revenues. The migration and benefits of the evolution from GPRS/EDGE to HSPA and then to LTE are both practical and inevitable. When combined with the ability to roam globally, huge economies of scale, widespread acceptance by operators, complementary services such as messaging and multimedia, and a wide variety of competitive handsets and other devices, the result is a compelling technology family for both users and operators. Today, over 135 commercial UMTS/HSDPA networks and 181 UMTS networks are already in operation. UMTS/HSPA offers an excellent migration path for GSM operators as well as an effective technology solution for green field operators. EDGE has proven to be a remarkably effective and efficient technology for GSM networks. It achieves high spectral efficiency and data performance that today supports a wide range of applications. Evolved EDGE, available in the 2007 timeframe as part of Release 7, will greatly enhance EDGE capabilities more than quadrupling throughputs. Whereas EDGE

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is extremely efficient for narrowband data services, the UMTS/HSPA radio link is efficient for wideband services. Unlike some competing technologies, UMTS today offers users simultaneous voice and data. It also allows operators to support voice and data across their entire available spectrum. Combined with a comprehensive QoS frame work and multimedia support, a network employing both EDGE and UMTS provides an optimal solution for a broad range of uses. HSDPA has significantly enhanced UMTS by providing a broadband data service with user achievable rates that often exceed 1 Mbps in initial deployments and that now exceed 3Mbps in some commercial networks. Today’s devices support peak network rates of 7.2Mbps, and the technology itself has a theoretical maximum network rate of 14 Mbps. Latency is very low, often below 100 msec. Not only are there continual improvements in radio technology,but improvements to the core network through flatter architectures particularly EPS will reduce latency, speed applications, simplify deployment, enable all services in the IP domain, and allow a common core network to support both LTE and legacy GSM/UMTS systems. HSPA and its advanced evolution can compete against any other technology in the world, and it is widely expected that most UMTS operators will eventually upgrade to this technology. While HSDPA improves throughput speeds and spectral efficiency for the downlink, HSUPA improves these for the uplink. Other innovations, such as MIMO, will be deployed over the next several years. Evolved HSPA+ systems, with peak rates of 42 Mbps, will largely match the throughput and capacity of OFDMA-based approaches in 5 MHz. 3GPP adopted OFDMA with 3GPP LTE, which will provide a growth platform for the next decade. With the continued growth in mobile computing, powerful new handheld computing platforms, an increasing amount of mobile content, multimedia messaging, mobile commerce, and location services, wireless data has slowly but inevitably become a huge industry. EDGE/HSPA/LTE provides one of the most robust

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portfolios of mobile-broadband technologies, and it is an optimum framework for realizing the potential of this market[15].

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Chapter 5

Design steps of HSPA

5.1 Technical background for HSDPA

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5.1.1 Aspects of capacity, throughput and coverage: HSDPA capacity and throughput for HSDPA depends upon a number of factors, including user location, the radio channel, user mobility and scheduler behavior. One way of viewing mobile network capacity problem is that both the instantaneous demand and the channel capacity are time varying. For voice centric networks, the law of large numbers can be invoked to develop reasonably accurate analytical performance models. Blocking models (such as the Erlang equations) can be used to define a Grade of Service (GOS) based on call setup success rate. On the other hand, broadband data networks often have a small number of users consuming large amounts of capacity, making the use of such assumptions invalid. Defining a measure of GOS for HSDPA should also consider the soft blocking nature of data (blocking now becomes delay). In this guideline, some simplified assumptions and models will be used to provide usable methods for estimating cell and system capacity and their relationship to coverage. To do this, the concept of a Maximum Cell Throughput will be used as a capacity measure. This models the maximum data rate that can be delivered to a hypothetical single user at a location in the target cell. It has the following as key inputs:

• Cell layout geometry (e.g. cells on a hexagonal grid) • Own-cell and other-cell power loadings • Radio channel model and associated C/I performance characteristic

• Transmit diversity (optional) • advanced UE features such as G-RAKE, LMMSE or receive diversityThis measure does include multi-user performance as it assumes a full scheduler delivering packets to a single hypothetical user (with a UE capable of the maximum bit-rate). Multi-user capacity can be estimated by applying an average multi-user gain to the maximum cell throughput (obtained from simulations or field measurements). Some consideration of a GOS (based on block error rate) is implicit in the approach used in this guideline through the

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throughput curves used to characterize performance. These are based on simulation studies with a nominal BLER (10%) as the throughput criteria. In this guideline, the maximum cell throughput will be calculated in two ways:. Maximum Cell Throughput vs. Signal Attenuation: This estimates the maximum throughput for a hypothetical UE is it travels radially from the target cell. The throughput profile is assumed to be the same for all directions from the target cell.. Cell Capacity: This measure estimates the average throughput for all locations in the target cell. User distributions can be used to model clustering of users and hotspot traffic scenarios [16].

5.1.2 Capacity gains using proportional fair scheduling With multiple users, the cell capacity is shared between users competing for resources. Factors that affect the throughput achieved by each user include: • delays for low bit rate transactional applications such as web browsing • multi user diversity gain (Proportional Fair) • latency • scheduler performance for large numbers of users • user mobility and the radio channelSimulations can be used to estimate the multi-user gain for different scenarios.This gain can then be applied to the cell capacity estimate.5.2 New HSDPA featuresUE categories: 3GPP Release 7 specifies 18 UE categories, six of which are new (Table5.1) and introduces support for MIMO and 64QAM modulation, with correspondingly higher data rates. Categories 17 and 18 UEs have the option of using either higher order 64QAM modulation or MIMO. This guideline does not support the calculation of MIMO throughput and capacity.

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Table (5.1) HS-DSCH Categories for 3GPP Release 7

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Higher order modulation: 64QAM Higher order modulation using 64QAM was standardized in 3GPP Release 7 for UE HS-DSCH categories 13, 14, 17 and 18. 64QAM provides peak L1 HS-PDSCH rates up to 21.096 Mbps (15 codes, Category 18). 64QAM is more sensitive to channel impairments (fading and multipath) and as such is expected to only be possible in very good radio conditions - typically close to the cell with good line-of-sight to the target cell and negligible other-cell interference. A power back-off is used to ensure modulation quality is maintained [17].

Transmit diversity:Transmit Diversity (TXD) is available as an optional feature using open loop Space Time Transmit Diversity (STTD). Modulation symbols are permutated and mapped onto two separate transmit antennas. TXD is used on a per UE basis, based on the UE capability. Where TXD is required, the channel power is split equally between the two diversity antennas. For non-TXD mode, the full channel power is transmitted on the main antenna branch. TXD provides improvements in HSDPA coverage and capacity through a reduction in the required Eb/No or C/I. Users in noise or other-cell interference limited conditions can expect to achieve an improvement in coverage and throughput. Capacity gains are also expected if a significant number of users are in noise or other-cell interference limited conditions.

Advanced UE receivers: The 3GPP standards specify requirements for number of advanced receiver types that can reduce the required signal to noise ratio required for a specific service quality. These are called Types 0,1,2,3 and 3i as outlined in Table(5.2), along with common implementations.

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Table(5.2) Advanced UE Receiver Features.

These features improve performance as follows: • UE Receive Diversity improves performance in other-cell and thermal noise limited environment. Performance will be largely be determined by the spacing and gains of the UE antennas which can be internal or external to the UE. Minimal gains are expected with same-cell interference limited environments due to the 100% correlated fading of signal and interference.• Own-Cell Interference Cancellation (IC) reduces the impact of same-cell interference. Common methods used are G-RAKE1 demodulation or LMMSE equalization prior to a standard RAKE demodulator.• Other-Cell Interference Cancellation reduces the impact of interference from other cells. These types of receivers are more complex and require considerably more processing power.5.3 HSDPA power considerations The RBS power available for HSDPA is determined dynamically, depending upon the R99 power usage as shown in Figure (5.1).

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Figure(5.1) Cell power usage with HSDPA. HSDPA takes whatever power is available from the RBS power after DCH, CCH and MBMS have been

allocated.

The R99 DCH and MBMS powers used for HSDPA throughput calculations are time averaged powers. For short time periods the R99+MBMS power may increase above the admission threshold reducing the power available for HSDPA. In extreme cases the R99 power may even take all available RBS power. For the analysis that follows, an average total power (Ptot) in the wanted cell is calculated or assumed. This power includes common channels, R99 dedicated channels, MBMS and an average HSDPA load power P HS,avg .

……………………(5.1)

The total power in other surrounding cells is assumed to be scaled relative to Ptot by a factor ψ [4]. Equal average power loading in all cells occurs when ψ=1. For the purposes of calculating the

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maximum rate, HSDPA is allowed to use all the remaining power, i.e.:

…………(5.2)

Figure(5.2) Power allocation for target own-cell and power scaling in other cells.

For a fully loaded network, Ptot should be approximately 75% Pnom.

5.4 Dimensioning Process The HSDPA RN dimensioning process is outlined in Figure(5.3) and Figure(5.4).The process first requires the network topology and cell size to be defined. The next step involves setting the total average power levels on the target cell and surrounding cells. This is made up of the outputs of the CCH, DCH, EUL and MBMS dimensioning, plus some notional average HSDPA power load, which together defines the average power loading of the network cell. Next, a coverage based throughput calculation is performed. This takes as inputs a number of network, UE and channel parameters. The output of this stage is throughput vs. signal attenuation or distance values. The final step is the capacity calculation. Subscriber

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distributions and multiple user capacity gain can be included in this step.

Figure( 5.3). Overview of the HSDPA dimensioning process flow chart for throughput and capacity calculations.

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Figure(5.4). HSDPA dimensioning workflow

5.5 HSDPA throughput and capacity calculationsIn this section several equations will be provided for ultimately calculating the maximum cell capacity. The first (section 5.5.1) is an expression for the Effective Carrier to Interference plus Noise Ratio (CINReff). This is then used in a throughput expression in section (5.5.3) to estimate the maximum cell throughput. These two equations are the basis for modeling of network capacity

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described in the following section. The basis for the CINR analysis is the following general expression for CINR measured at the final detection stage of the RBS receiver:

………………(5.4)

Each of the terms has a separate gain (Gown,Gother and Gn) and margin (εown, εother, ε n) which are constants defined for

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different radio channels and system capabilities. The effect of a gain (margin) term is to increase (decrease) the associated C/N or C/I term.

5.5.1 CINR equation: To develop the final CINR expression, the wanted HSDPA power is set to C=PHS,max and margins for fast fading (εfading) and CQI measurement errors (εcqi) are applied to equation (5.4). Separate gain terms are included for the C/I and C/N terms, resulting in the following:

………………..(5.5)

Next, the own-cell interference is set to Iown = αPnom and the other cell interference to other tot I =FψP (refer Figure5.2). Including these into equation (5.5) results in the following expression (provided in three equivalent forms):

…………………….(5.6)

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where: α : is the radio channel downlink non-orthogonality factor. ψ: is a factor for scaling power levels in other-cells relative to the own cell.

ε fading: is a margin modeling small scale fast fading. εcqi:is a margin modeling CQI measurement errors. F: is the ratio of other-cell to own-cell interference, with equal power transmitted from all cells.

G own: is a gain applied to the own-cell C/Iown term. G other: is a gain applied to the C/Iother term. G n: is a gain applied to the C/N term. L sa: is the mean signal attenuation between the system reference point and the UE input.Nth: is the equivalent thermal noise level (in Watts) referenced to the UE receiver input and includes noise generated by the UE receiver.

k = 1.38x10-23, T = 290 and B = 3.84 MHz, N f is theUE noise figure.P HS,max : is the maximum power (in Watts) available for HSDPA in the target cell at the system reference point.P tot: is the total power (in Watts) transmitted by the targetcell at the system reference point.P nom: is the maximum transmitter power (in Watts) at thesystem reference point.

All power levels are referenced to the system reference point through the term Lsa, and all quantities are in linear units.

5.5.2 CINR equation discussionThe following is included as a guide to understanding the various components of equation (5.6).

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C/I and C/N terms: The three main terms in equation (5.6) are now considered separately:Own-cell:

• Both C and I own are subject to the same correlated fading and no fading margin is applied.• Gown models the suppression of own cell interference or equalization with advanced UE receivers.• α accounts for the portion of the wanted signal appearing as noise due to multipath channel.• ε CQI accounts for CQI measurement errors.

Other-cell :

• I other is the sum of interference from multiple other cells and has the same effect as thermal noise.• Fading of C and I other is assumed to be uncorrelated and therefore a fading margin εfading is applied, along with a CQI error margin ε CQI .• Gother models gains of TXD or RXD and other-cell IC with Type3i UE receivers.• P/ P tot nom scales maximum to average cell power.

Thermal Noise :

• N is referenced to the system reference point through Lsa.• Fading of C and N is uncorrelated and a fading margin εfading is applied.

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• GN models gains of TXD or RXD.

Gains-and-margins Fading and CQI errors (ε fading and ε CQI ): Radio channel fading has been modeled with a parameter ε fading applied to only the other-cell interference and thermal noise components. This is not applied to the C own\ I term as the target cell signal and interference levels fade together and the ratio is constant. The effect of ε fading in equation (5.6) is to increase the relevant noise or interference term, thus reducing CINReff. To account for CQI measurement errors in fading channels resulting in non-optimal HS-DSCH format selection, a separate parameter ε CQI is applied to all terms. In noise or other-cell interference limited environments, the total fade margin is assumed to be the product ε fading ε CQI . In own-cell interference environments, only the ε cqi-margin-is-applied. Own-cell gain ( own G ): The gain term G own models the partial cancellation of own-cell interference achieved with Types 2,3 or 3i UE Receivers. G own compensates the channel non orthogonality factor α, and for perfect cancellation/equalization, G own →∞. There are no receive antenna or transmit antenna diversity gains applied to the own cell C/I term since both the wanted signal and interference fading are assumed to be 100% correlated. Values for Gown can be estimated using the values for RAKE and G-RAKE receiver performance given in [1].

…………………(5.7)

Other-cell gain (G other ): The composite gain term G other models the following:

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1. An increase in CINReff in fading due to UE receive diversity gain (G rxd ) and RBS transmit diversity gains G txd . G other is a function of both these gains and is not necessarily equal to G txd G rxd. Since diversity cannot improve performance more than the composite fading and CQI error margins, the restriction Gother ≤ε fading ε cqi applies (assuming no IC).2. A reduction in other-cell interference with Type 3i receivers. IC is assumed to be independent of diversity gains, and hence G other →∞ for perfect cancellation.Noise gain (G n ): The gain term G n models the effects of transmit and receiver diversity gains which combat channel fading and CQI errors. As before, the restriction Gn≤εfading εcqi applies. The choice of gain values is dependent on advanced receiver functions (IC and RXD) and downlink TXD. Table (5.3) summarizes the relationship between advanced receiver types described , and the range of values for three gains terms. Default values are provided assuming no advanced features are used. A more comprehensive treatment of these gain terms is outside the scope of this guideline.

Table (5.3) Summary of CINR equation gains and ranges.

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5.5.3 HSDPA throughput equationThe basis for the model used in this section is a throughput function describing the maximum RLC throughput vs. the carrier to noise ratio. This function represents the best possible throughput in a non-fading and non dispersive radio channel. The function has been obtained by fitting a modified Shannon capacity equation to simulation results. Two parameters are used to perform the fit and these compensate for the difference between the Shannon limit rate and the rate achieved with specific turbo coding schemes1. The RLC throughput is given by:

….(5.8)Where: CINR eff: is the signal to total noise plus interference ratio in dB. B: is the channel bandwidth (3840 kHz). K0 , k1: are model constants

:is the maximum rate supported by cell modulation/code format (kbps).

: is the maximum supported UE rate.

ηRLC: is an RLC efficiency factor accounting for RLC overheads.

Table (5.4) list the default parameters for equation (5.8) with a sample set of Layer 1 throughput curves shown in Figure (5.5).

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Table(5.4) Default parameter values for the throughput function.

Figure (5.5) RLC throughput curves throughput for various modulations and code formats in an additive white gaussian noise, static non-dispersive

channel.

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5.6 Network modelingIn this section, aspects of the network modeling are presented so that the throughput and capacity equations in the previous section can be applied. Topics covered include network and cell topology, F values, modeling orthogonality, cell border calculations, and modeling non-uniform subscriber distributions.

5.6.1 Network and cell geometry: The network geometry that will be used for evaluating coverage and capacity is illustrated in Figure (5.4) with the target cell being one sector of a three-sectored site with a regular hexagonal layout. The cell border is defined by the distance to the furthest vertex, d max =R. The median signal attenuation loss is L sa,max at this point.

Figure(5.6) Network Geometry.

The geometry of the target cell is shown in Figure (5.7). To a first approximation, the signal attenuation to all points in the ith ring can be considered equal. This is based upon the assumption that antenna gains off bore-sight will be less than the bore-sight gain. Antennas commonly used for sectored sites have beamwidth of

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around 65° with a relative gain at X. of -10dB. This matches the reduced path loss along OX. which is estimated to be 10 dB less than for the same distance on the antenna boresight.5.6.2 Average F-values: Across the target cell, the average F value will vary, being highest in the inter-site border regions. Tables of F values are obtained through simulation for various antenna tilts and aggregated into average F values for each .ring. in Figure (5.7). Tabular data for average F values is provided in Appendix A and plotted in Figure (5.8).

Figure (5.7). Target cell geometry used for cell capacity calculations.

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Figure (5.8) Average F values. Hexagonal layout of tri-sectored RBS, 30 metre antenna height and 65° antenna beamwidth.

5.6.3 Alpha values: Values for the channel non-orthogonality α are usually based on standard channel models defined on the basis of an average path profile for a particular cell size. However delay-spread profiles can be expected to change as a function of distance from the cell site. As a general rule, delay-spread will increase with distance from the cell. Closer to the cell site, fading can be expected to become more Rician as a line of sight component becomes more dominant with insignificant multipath components. Since the performance of HSDPA is strongly affected by α (especially high peak data rates), it is reasonable to use a model to decrease α closer to the cell site. A model for doing is:

…………………………..(5.9)

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Where: α nom: is the nominal α value from [1]. d′: is the normalized distance / .0 1 max d′ =d d ≤d′≤ a1,a2 ,a3: are model constantsScaling is performed with respect to the nominal value αnom obtained with two sets of recommended model constants provided . The uniform set of parameters sets α = αnom across the whole cell, while the second set causes α to asymptote to αnom at the cell edge as shown in Figure (5.9). 5.6.4 Setting the cell border attenuation: Setting the cell border signal attenuation (Lsa,max) is an essential step in the coverage and capacity calculations. Two methods for calculating this are provided here. The first method is based on a given cell site spacing. Obviously this method cannot be applied to isolated cells. The second method is based on an uplink throughput criterion and can also be applied to isolated cells.

Figure (5.9) Alpha scaling model showing α/αnom vs. relativedistance to the cell border.

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. Method 1 cell spacing is provided : Given a cell site spacing in km, standard path loss models (e.g. COST 231) can be used to calculate the median cell border path loss Lp,max [1]. The median signal attenuation to a user at the cell border is then:

…………….(5.10)

Where: L BL: is a body loss margin [dB] L CPL: is a car penetration loss margin [dB] L BPL: is a building penetration loss margin [dB] L J: is the ASC/Antenna jumper loss [dB] G a: is the combined UE and RBS antenna gains [dBi]A log-normal fading margin is not used in these calculations, as the cell spacing isfixed and standard path loss models calculate the median path loss.. Method 2 uplink criterion determines the cell spacing : This method involves calculating the maximum uplink path loss Lpmax,UL based on EUL throughput criteria as outlined and can be applied to isolated cells. Given an EUL throughput criterion, the cell border signal attenuation Lsa,max is calculated. If throughput reliability greater than 50% is required, a log-normal fading margin can be included in the EUL calculation. In subsequent HSDPA coverage calculations, no log-normal fading margin is required for coverage as the median throughput is calculated in the throughput equation. If a cell border throughput figure with a higher reliability is required, a margin can be used . however this should be applied once the throughput vs. Lsa curve is obtained and the impact of applying a margin is understood. This is illustrated in Figure (5.10). In the C/N limited region, a margin can be applied with an increase in the throughput reliability. However in the own-cell or maximum rate limited region3, applying a margin will not significantly improve the throughput reliability.

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Figure(5.10) Illustration of cell border throughput with and without a log-normal fading margin. At Lsa,1, the throughput can be expressed as R1

(50% reliability) or R2 (>50% reliability).

5.6.5 Network coverage calculations: The throughput function in equation (5.8) describes the expected median throughput as a function of signal attenuation or relative distance to the cell border, and can be obtained by: 1. Calculating or choosing network power and throughput parameters. 2. Calculating or choosing the cell border signal attenuation (Lsa,max). 3. Calculating CINR eff using equation (5.6). 4. Calculating the maximum Layer 1 throughput (excluding retransmission) using γ = CINR eff in equation (5.8).Lsa can be converted to a distance ratio (applicable only in the bore-sight direction for sectored cells) using:

…………………….(5.11)

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Where n is the path loss exponent (typically 3.5) and Lsa,max and Lsa are in dB.

Conversely, Lsa can be calculated from a distance ratio using:

……………………(5.12)This calculation can be used to create a throughput profile curve as a function of Lsa or d/dmax.

5.6.6 Network capacity calculations: The basis of capacity calculation involves averaging the throughput function over the cell area. This is done by calculating a weighted mean of the throughput vs. distance function. The hexagonal cell area in Figure(5.7) is divided up into N rings each with an area proportional to ( ) which is used as a weighting function wi to calculate the cell throughput:

……………………..(5.13)

Where:

The number of rings N determines the accuracy of the approximation. In C/N limited regions where throughput decreases with distance, summation errors can be significant (5-10%). Use a ring interval ≤2% for capacity calculations

5.6.7 Multi-user capacity : The method described so far, estimates the average cell capacity in terms of aggregate throughput using a single user model. This capacity estimate is an

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average over all locations in the cell. In a multi-user environments, a multi-user diversity gain is possible if users in good radio environments (capable of high bit rates) are given priority over users in poorer radio environments. Evaluating multi-user capacity gains is not a simple task, with complex simulations being the only viable option. The gain is a function of many variables including user distribution, terminal capabilities, user speed and radio channel conditions. These simulations (and also supported by field trials) have shown that capacity gains of 20% to 40% are achievable using a Proportional Fair scheduling algorithm[17].

The cell capacity with multiple users is estimated using:

…………………(5.14)

where: T cell,multiuser: is the throughput capacity using the proportional fair scheduler algorithm. T cell: is the single user average cell throughput. G multiuser: is the multi-user capacity gain factor (G multiuser ≥1 ). R max RBS : is the maximum rate supported by the RBS.

Use Gmultiuser = 1.3 (30% gain) for multi-user capacity dimensioning.

5.6.8 Isolated cells: Isolated cells can include geographically isolated cells with minimal or no interaction with other cells, isolated second carriers or cells with in-building systems with dominant coverage. The capacity and coverage formulas are applicable to isolated cells with the following differences:• the concept of hexagonal rings is replaced by circular rings

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• cell border signal attenuation (Lsa,max) is defined by an uplink calculation• Lsa can be mapped to distance for all azimuths for omni-directional sites• ψ is set to zero to remove interference from other cellsThere is no change to any formulas or other parameters.

5.6.9 Method for including subscriber distributions: Significant capacity increases can occur if subscribers are located in good RF conditions. This is often the case in real networks where sites are located to match the subscriber locations (e.g. town centers, major buildings etc.). The calculation for cell capacity described by equation (5.13) can be extended to include subscriber distributions by modifying the weighting function as follows:

…………………….(5.15)

The subscriber weighting values are relative weightings, and do not need to sum to 100%. This approach might be used where network performance statistics of path loss are available. This formula can be used to model a single hotspot capacity with users clustered at a specified Lsa.Table(5.5) illustrates the form of the capacity calculations for a network model with non-uniformly spaced rings, and two hotspots (one near the cell border, and the other close to the cell). The cell border signal attenuation is 140 dB in this example.

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Table (5.5) Illustration of weightings with non-uniform ring spacing and two. Hotspots .. This table shows how weighting values are calculated from

distance and subscriber weights.

While the subscriber weighting values can be arbitrarily chosen, it is sometimes convenient to model these based on a log-normal distribution:

…………….(5.16)

where L sa,avg and are the signal attenuation mean and standard deviation respectively (in dB)4.This approach might be used where network performance statistics of path loss (mean and standard deviation) are available.[16]

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This formula can be also be used to model a single hotspot capacity with users clustered at L sa,avg , by letting σ L →0 .

Figure(5.11) Subscriber distribution weighting functions for (a) Lsa,avg = 120 dB, σL = 10 dB, and (b) Lsa,avg = 110 dB, σL = 2 dB.

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5.7 CALCULATION

5.7.1 HSDPA power calculation: P tot=PCCH+PDCH+PMBMS+PHS,avg

Ptot=4.84+0+0+10.2=15W

PHS,max=Pnom-(PCCH+ PDCH+PMBMS)

PHS,max=20-(4.84+0+0)=15.16W

5.7.2 HSDPA throughput and capacity calculations:

= 1.39

where :

α =0.3, ψ=100%, ε fading =2.4W, ε cqi =1.3W, F=0.29, G own = 2W, G other =1.9W, Gn =1.9W, L sa=125dB, N th=-102.7

PHS,max =15.2W, P tot=15W, Pnom =20W

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4W=

2.1W =

=53.6W

5.7.3Throughput Calculation:

=3601KbpS

cell border Calculation:

the cell border attenuation is calculated as Lp,max = 130.6 dB. This was derived from a EUL uplink calculation for a cell border bit rate of 128 kbps and includes 18 dB building penetration loss and 7.5 dB log-normal fading margins. Other losses and margins were equal to 0 dB.

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= 130.6+0+0+0+18-18=130.6 dB

Network capacity calculations :

The cell capacities for the three scenarios are estimated using equation (5.13). This can be implemented in a spreadsheet with a sumproduct formula, Capacity =sumproduct(N3:N52,G3:G52)/sum(G3:G52)The calculated cell capacities for the three scenarios are listed in Table (5.6). Finally, in order to illustrate the impact of R99 DCH loading, cell capacities for 5W and 10W R99 DCH power load are calculated using the same method. In both cases, the average HSDPA power PHS,avg was calculated to maintain the assumption of Ptot/Pnom = 75%. Results are contained in Table (5.7) and Table (5.8).These results show that even at high R99 DCH loads, reasonable HSDPA throughputs can be achieved.

Table(5.6). Cell capacity results with no R99 load. Multi-user capacity gain factor=1.3.

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Table(5.7). Cell capacity results. 5 W R99 DCH load.

Table(5.8).Cell capacity results. 10 W R99 DCH load.

Multi-user capacity

= 4.3Mbps

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Chapter 6 Conclusion

6.1 Conclusion1-High-Speed-Packet-Access-(HSPA)-is-the-next-step-in-the evolution of WCDMA 3G technology, and greatly improves data

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speed and capacity for packet-data communication. It also allows WCDMA mobile operators to enhance their data offerings while freeing-them-up-to-introduce-new-services.

2-WCDMA with HSPA has introduced users to a variety of applications with superior performance: three to four times higher system capacity, data speeds measured in megabits per second, and substantially-shorter-response-times.

3-Today users are accustomed to turning on their mobile phones and having them work almost everywhere.-The same level of connectivity is now possible with laptops and other devices equipped with embedded HSPA mobile broadband modules.

4-HSPA is being embedded in laptops now and will soon be included in a wide range of other consumer electronics devices, such as gaming systems, digital cameras, GPS navigators, and car maintenance systems.

5-HSPA can be built out using existing GSM radio network sites and is a software upgrade of installed WCDMA networks. When used together with dual-mode terminals, these factors help ensure nationwide coverage for voice (GSM/WCDMA) and data (HSPA/EDGE). Furthermore, HSPA gives operators a single network for multiple services and a sound business case built on revenues from voice, SMS, MMS, roaming customers and mobile broadband services

6-HSPA mobility is provided by the three optional features HSDPA Mobility, HSDPA Mobility phase 2 and Enhanced UL Mobility. The HSDPA and EUL serving cells are always the same, and the serving cell change is performed for HSDPA and EUL at

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the same time. Cell change is triggered by the same triggers as when HSDPA only is used. On top of normal intra-frequency cell change these features provide additional mobility improvements.

7-The HSPA performance depends on a large number of factors. Many are related to the radio network (capacity, radio quality, feature usage, HSDPA power headroom etc), while others depend on the core network, Internet, servers, the application used etc.

8-The HSDPA efficiency KPIs is used to analyze how well the “HS pipe” transmits the data on the downlink and how well applications in combination with Iub flow control succeed to fill the RBS buffers with data. HSDPA the most important resource is transmission power. Therefore it is important to monitor power KPIs to understand the HSDPA performance.

9-Today, HSDPA offers the highest peak data rates of any widely available wide-area wireless technology. With continued evolution, peak data rates will continue to increase, spectral efficiency will increase, and latency will decrease. The result is support for more users at higher speeds with more applications enabled. Application scope will also increase, with QoS control and multimedia support through systems such as IMS.

10-HSDPA has significantly enhanced UMTS by providing a broadband data service with user achievable rates that often exceed 1 Mbps in initial deployments and that now exceed 3 Mbps in some commercial networks. Today’s devices support peak network rates of 7.2Mbps, and the technology itself has a theoretical maximum network rate of 14 Mbps. Latency is very low, often below 100 msec.11- HSPA and its advanced evolution can compete against any other technology in the world, and it is widely expected that most UMTS operators will eventually upgrade to this technology. While HSDPA improves throughput speeds and spectral efficiency for the

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downlink,-HSUPA-improves-these-for-the-uplink. Other innovations, such as MIMO, will be deployed over the next several years. Evolved HSPA+ systems, with peak rates of 42 Mbps,will largely match the throughput and capacity of OFDMA-based approaches in 5 MHz. 3GPP adopted OFDMA with 3GPP LTE, which will provide a growth platform for the next decade.

12-HSPA+ will significantly increase HSPA capacity as well as reduce latency below 50 milliseconds (ms) The first phase of HSPA+ with 64 QAM has already been deployed commercially and is providing peak theoretical downlink throughput rates of 21 Mbps.

13-The deployment of HSPA on the 2.6GHz frequency band also stimulates current HSPA operators to further grow their existing mobile broadband business into new frequency bands, as it allows them to leverage existing infrastructure, providing greater cost efficiency, and supports a wider range of end-user devices.

14-HSPA is a proven technology and the leading industry standard. It is already deployed in several frequency bands - including 850, 1700, 1800, 1900 and 2100MHz - and deployment in the 900MHz frequency band will start soon. Support in the 2.6GHz frequency band brings the economies of scale of HSPA also to operators with 2.6GHz licenses and their end users.

15-Throughput is used to describe the data rate. It is possible to measure throughput for each protocol layer separately, such as MAC-e/MAC-hs and RLC layers as well as for TCP/IP layer. Each protocol layer adds header and functionality. 16-Today, HSPA is available in more than 130 live networks worldwide with more than 50 additional deployments ongoing.

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17-Improving coverage of WCDMA through colocation will make it possible to provide mobile broadband everywhere for everyone, and can be shown to be a good business case for the operator.

18-We can conclude that HSDPA shows no significant network capacity gain.It is in fact, a means to increase throughput and reduce delay in low loaded networks. In the interference limited WCDMA environment, HSDPA gains from assigning all available power in a cell to the active connections. If the network reaches its interference and power limitations, channel conditions are disturbed and only robust transmission as usual, i.e. without HSDPA is possible. But with the introduction of fast scheduling and HARQ, HSDPA offers more flexibility for fair resource sharing among users. Hence, WCDMA network capacity for multiple transmissions is not significantly increased but efficient sharing of the limited resources in terms of codes and power can be realized and higher peak throughput is achieved for single connections.

19-HSPA gives carriers an efficient mobile broadband technology that can evolve to HSPA+ to meet the advanced wireless needs of customers. To leverage operator investments in HSPA and enhance the quality of service across networks.

20-we says that HSPA is revealing the full potential of mobile broadband applications and services. development and persistent innovation will continue with the deployment of LTE, providing enhanced data throughput speeds and all-IP network capabilities.

21-WCDMA/HSPA solution for the 900MHz band provides more coverage because of the improved radio wave propagation at lower frequencies, making it easier to provide low-cost mobile

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broadband services in rural areas as well as improved indoor coverage in urban areas.

22- The deployment of HSPA stimulates current HSPA operators to further grow their existing mobile broadband business into new frequency bands, as it allows them to leverage existing infrastructure, providing greater cost efficiency, and supports a wider range of end-user devices.

23- In the near future, even faster data speeds made possible with HSPA Evolution will further enhance the user experience by enabling advanced services such as mobile TV and even TV on a user's home screen.

24-We says The improved speed will assist operators in leveraging existing network infrastructure to meet growing consumer appetite for advanced multimedia services. High-performance mobile broadband will not only drive the uptake of mobile services and convergence of devices, but will also enable operators to combine their fixed and mobile networks in order to extend broadband to 100 percent of the population

REFRENCE

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1-Goldsmith A,Stanford University,2005.Wireless communication. Cambridge University Press.

2-www.zte.com.cn

3-Internet High-Speed Packet Access(I-HSPA),Nokia Siemens Networks

4-“GSM Technical Data”.Cellular.co.za.

http://www.cellular.co.za/gsmtechdata.htm. Retrieved 2010-08-30.

5-Ericsson world-first in delivering innovative 3G technology to Telstra-Press Release.

6-from Wikipedia the free encyclopedia.

7-www.ericsson.com

8-www.umtsworld.com/technology/WCDMA.htm

9-www.funsms.net

10-www.NetworkDictionary.com

11-http//www.Wisegeek.com

12-3G Americas:”The Evolution of UMTS,3GPP Release 5and Beyond,”June2004

13-Ericsson: “HSDPA Performance,” July 2005,submission to 3G Americas

14-3GPP-LTE-Performance-Summary,-Downlink,Uplink,VoIP. multi-vendor assessment.2007.

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15-Cingular Wireless “Spectrum Efficiency Comparison GSM vs. UMTS vs.1XRTT”-research material,March 14,2002,submission to 3G Americas

16-Radio Network Dimensioning guideline for Enhanced Uplink, 18/100 56-HSD 101 02/6 Rev A.

17-HSPDA Deployment Guideline.

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