Wcdma Air Interface Ch1

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Slide title In CAPITALS50 pt Slide subtitle32 pt WCDMA AIR INTERFACEChapter 1 WCDMA Wireless Technology Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles1 Objectives of Chapter 1, WCDMA Technology After this chapter the participants will be able to: 1. Explain the fundamental principles of cellular WCDMA technology. 2. Explain and compare TDMA and WCDMA multiple access methods. 3. Explain on an overview level, the WCDMA transmitter architecture. 4. Explain the data protection coding methods: CRC Coding, FEC Coding, Viterbi decoding, block interleaving, turbo codes. 5. Explain the use of channelization and scrambling codes. 6. Explain the modulation and filtering in a WCDMA system. Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles2 WCDMA Air Interface World Administrative Radio Conference (WARC) of the ITU (International Telecommunications Union) in 1992 chose frequencies around 2 GHz as available for use by third generation mobile systems. Within the ITU these third generation systems are called International Mobile Telephony 2000 (IMT-2000). Within IMT-2000, several different air interfaces are defined for third generation systems based on either CDMA or TDMA technology. The same air interface,WCDMA, is to be used in Europe and Asia, including Japan and Korea using the frequency bands around 2 GHz. In North America that spectrum has already been allocated for operators using second generation systems and no new spectrum is available for IMT-2000. Thus third generation services must be implemented within the existing bands. Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles3 WCDMA Air Interface As well as WCDMA the other air interfaces that can be used are EDGE and cdma2000. EDGE (Enhanced Data Rates for GSM Evolution) can provide bit rates up to 500 kbps within a GSM carrier spacing of 200kHz. Cdma2000 can be used as an upgrade for the existing IS-95 operators Spectrum allocation in Europe, Japan and Korea is 1920 - 1980 MHz uplink and 2110 - 2170 MHz downlink for Frequency Division Duplexing. 1900 - 1920 MHz and 2020 - 2025 MHz for Time Division Duplexing. Frequency Division Duplex use different frequency bands for uplink and downlink while Time Division Duplex use the same frequency for both uplink and downlink. Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles4 From 2G to 3G Circuit-Switched Voice Circuit-Switched Data Circuit-Switched AMR coded voice Circuit-Switched data Packet Data Streaming Short Message Service (SMS) 2G 3G Multiservice: AMR coded voice + Packet dataTop right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles5 RABsVariable rate Packet Switched RACH/FACH, 64/64, 64/128, 64/384, 64/HS, 384/HS Combination of Conversational Speech and Interactive 64/64 Conversational/speech RAB Conversational 64 kbps CS RAB CS RABs Interactive or background PS RAB PS RABs Streaming 57.6kbps RAB PS Streaming RAB 12.2 kbps Circuit switched64 kbps Circuit switched57.6 kbps Circuit switched Maximum Bitrate 16/64 Guaranteed Bitrate 8/54 Multi-RAB Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles6 New P5 RAB combinations CS Conversational Speech Multi Mode AMR Speech 12.2PS Interactive 64/64 PS Interactive 64/64 PS Interactive 64/64, 64/128 PS Interactive 64/64, 64/128 Speech 12.2 kbpsPS 64/128, 128/64, 64/384, 64/HS, 384/HS PS Interactive EUL/HS Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles7 Multiple Access Approaches Frequency Division Multiple Access Each User has a uniquefrequency (1 voice channel per user) All users transmit at the same time AMPS, NMT, TACS User 1 User 2 User 3 Frequency Each Transmitter has a uniqueScrambling Code Each Data Channel has a unique Channelization code Many users share the same frequency and time IS-95, cdma2000, WCDMA Frequency Code Division Multiple Access Spread Spectrum Multiple Access Multiple Transmitters and Multiple Data Channels Each User has a uniquetime slot Each Data Channel has a unique position within the time slot Several users share thesame frequency IS-136, GSM, PDC Time Division Multiple Access User 1 User 2 User 3 User N Time Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles8 Data Multiplexer Transmit Gating The TDMA Transmitter Control/ Signaling Data Filtering + RF Modulation RF Out Sync.Bits User Data Channel N Error Protection Timeslot Selector Error Protection User Data Channel 1 Error Protection Vocoder Error Protection The Multiplexer allows various data channels to share the same timeslot. The timeslot selector allows multiple transmitters to share the same carrier frequency, by assigning a unique timeslot to each transmitter. Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles9 The WCDMA Transmitter Filtering + RF Modulation RF Out Linear Summation Control/ Signaling Data Sync.Bits User Data Channel N Error Protection Error Protection User Data Channel 1 Error Protection Vocoder Error Protection Frequency User 1 User 2 User 3 ... Channelization code 4 Channelization code N Channelization code 3 Channelization code 2 Channelization code 1 Channelization Codes provide unique identification of each data channel Scrambling Codes (SC) provide unique identificationof each transmitter Scrambling Code Scrambling Code Scrambling Code Scrambling Code Scrambling Code Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles10 CRC CodingFEC Coding Maps binary bits to real value symbols 0 +1 1 -1 Pre-coded data (bits) Pulse Shaping Filter RF Out Data Channel 1 Data Channel N E ChannelizationCode 1 Pulse Shaping Filter I/Q Modulator Inter- leaving CRC CodingFEC Coding Inter- leaving D/A I Q Allows for error detection in the receiver Allows for error correction in the receiver Improves error correctionin the receiver Gives a unique identity to each data stream Contains transmitted frequency spectrum Allows both signals from I and Q branch to share the same RF bandwidth Data Symbols Chips I Q Modulation Symbols 1:2 Demux Provides 2x higher data rate (WCDMA, cdma2000 downlink) 1:2 Demux I Q scramblingCode 1 ChannelizationCode n D/A I Q I Q scramblingCode 1 Gives a unique identity to this transmitter I Q Modulation Mapping WCDMA Transmitter (downlink) Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles11 Voice Coding Example:Two ways to hear the sax player Record the sax player onto a CD...... and play back the CD20 MB per song Write down the notes he plays...... and have a friend play the same notes 20 kB per song Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles12 Voice Coding Vocoding Human Voice: ss, ff, sh ~20% of time ah, v, mm , ~80% of time Transmitted Parameters 8~12 kb/s typical, vs. 64 kbps for log-PCM 32 kbps for ADPCM Vocoder White Noise Generator Pulse Generator E Voice Re-Synthesis at the Receiver Noise parameters Pitch parameters H(s) Filter poles correspond to resonances of the vocal tract Speech Output H(s) Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13-EN/LZU 108 5306UaeRev H. Figure 1-WCDMA Air Interface: WCDMA Principles13 ACELP/AMR Voice Coding A/D Linear Predictive Coding (LPC) Filter Codebook Index Codebook Perceptual Weighting Error Analysis Speech Generator Vocoder Output Bits MUX Voice, Tone Activity Detectors Mode Indication bits Comfort Noise Tone Emulation DTX Indication E (+) (-) Prediction Error Benefits of Activity Detection: 1)2)Top right cornerforfield-mark, customer or partner logotypes. See Best practice for example. Slide title40 pt Slide subtitle24 pt Text 24 pt Bullets level 2-5 20 pt 1/038 13