01 OWJ100001 WCDMA RNP Fundamental (With Comment) ISSUE1

www.huawei.com

Copyright © 2006 Huawei Technologies Co., Ltd. All rights reserved.

WCDMA RNPFundamental


Objectives� Upon completion of this course, you will be able to:

� Get familiar with principles of radio wave propagation, and

theoretically prepare for the subsequent link budget.

� Introduce the knowledge about antennas and the meanings of

typical indices.


Contents1. Radio Wave Introduction

2. Antenna

3. RF Basics

4. Symbol Explanation



1.1 Basic Principles of Radio Wave

1.2 Propagation Features of Radio Wave

1.3 Propagation Model of Radio Wave

1.4 Correction of Propagation Model


Radio Wave SpectrumRadio Wave Spectrum

The frequencies in each specific band present unique propagation features.

300-3000GHz

EHFExtremely HighFrequency

30-300GHzSHFSuper High Frequency3-30GHzUHFUltra High Frequency300-3000MHzVHFVery High Frequency30-300MHzHFHigh Frequency3-30MHzMFMedium Frequency300-3000KHzLFLow Frequency30-300KHzVLFVery-low Frequency3-30KHzVFVoice Frequency300-3000Hz

ELFExtremely LowFrequency

30-300Hz3-30Hz

DesignationClassificationFrequency


Propagation of Electromagnetic Wave

electric wave transmission directionElectric FieldElectric Field

Magnetic FieldMagnetic Field

Electric Field

Dipole

� When the radio wave propagates in the air, the electric field direction

changes regularly. If the electric field direction of radio wave is vertical to

the ground, the radio wave is vertical polarization wave

� If the electric field direction of radio wave is parallel with the ground, the radio

wave is horizontal polarization wave


Perpendicular incidence waveand ground refraction wave

(most common propagation modes)

Troposphere reflection wave(the propagation is very random)

Mountain diffraction wave(shadow area signal source)

Ionosphere refraction wave(beyond-the-horizon communication path)

Propagation Path


①①①①①①①① Building reflection waveBuilding reflection wave②②②②②②②② Diffraction waveDiffraction wave③③③③③③③③ Direct waveDirect wave④④④④④④④④ Ground reflection waveGround reflection wave

Propagation Path


Radio Propagation Environment� Radio wave propagation is affected by topographic structure

and man-made environment. The radio propagation

environment directly decides the selection of propagation

models. Main factors that affect environment are:

� Natural landform (mountain, hill, plains, water area)

� Quantity, layout and material features of man-made buildings

� Natural and man-made electromagnetic noise conditions

� Weather conditions

� Vegetation features of the region


Quasi-smooth landform

The landform with a slightly rugged surface and

the surface height difference is less than 20m

Irregular landform

The landforms apart from quasi-smooth landform

are divided to: hill landform, isolated hills, slant

landform, and land & water combined landform

R

T

T

R

Landform Categories


distance (m)

Receiving power (dBm)

10 20 30

-20

-40

-60

slow fading

fast fading

Signal Fading


Signal Diversity

Measures against fast fading --- Diversity

� Time diversity

� Space diversity

� Frequency diversity


Solution RAKE technologyRAKE technology

Radio Wave Delay Extension� Deriving from reflection, it refers to the co-frequency interference

caused by the time difference in the space transmission of mainsignals and other multi-path signals received by the receiver

� The transmitting signals come from the objects far away from thereceiving antenna


T

R

Diffraction Loss� The electromagnetic wave diffuses around at the diffraction

point

� The diffraction wave covers all directions except the obstacle

� The diffusion loss is most severe


Penetration Loss

XdBmWdBm

Penetration loss =X-W=B dBPenetration loss =X-W=B dB

� Penetration loss caused by obstructions:


),( fdfPathLoss =d f

Propagation model� Propagation model is used for predicting the medium value of path loss.

The formula can be simplified under if the heights of UE and base stationare given

where: is the distance between UE and base station, and is thefrequency

� Propagation environment affect the model, and the main factors are :� Natural terrain, such as mountain, hill, plain, water land, etc…;

� Man-made building (height, distribution and material);

� Vegetation;

� Weather;

� External noise


Lo=91.48+20lgd, for f=900MHzLo=97.98+20lgd, for f=1900MHz

Free Air Space Model

� Free space propagation model is applicable to the wireless

environment with isotropic propagation media (e.g.,

vacuum), and is a theoretic model

� This environment does not exist in real life


Ploss = L0+10χlgd -20lghb - 20lghm

χ Path loss gradient , usually is 4

hb BTS antenna height

hm mobile station height

L0 parameters related to frequencyR

T

Flat Landform Propagation Model


Application ScopeApplication Scope

CharacteristicCharacteristic

� Frequency range f:150~1500MHz� BTS antenna height Hb:30~200m� Mobile station height Hm:1~10m� Distance d:1~20km

� Macro cell model� The BTS antenna is taller than the surrounding buildings� Predication is not applicable in 1km� Not applicable to the circumstance where the frequency is

above 1500MHz

Okumura-Hata Model



� Frequency range f:1505~2000MHz� BTS antenna height Hb:30~200m� Mobile station height Hm:1~10m� Distance d:1~20km


� Macro cell model� The BTS antenna is taller than the surrounding buildings� Predication is not applicable in 1km� Not applicable to the circumstance where the frequency is

above 2000MHz or below 1500MHz

COST 231-Hata Model



� Frequency range : 800~2000MHz

� BTS antenna height Hbase : 4~50m

� Mobile station height Hmobile : 1~3m

� Distance d : 0.02~5km


� Urban environment, macro cell or micro cell

� Not applicable to suburban or rural environment

COST 231 Walfish-Ikegami Model


K1: Propagation path loss constant valueK2: log(d) correction factorD: Distatnce between receiver and transmitter (m)K3: log(HTxeff) correction factorHTxeff: Transmitter antenna height (m)K4: Diffraction loss correction factorK5: log(HTxeff)log(D) correction factorK6: Correction factor

: Receiver antenna height (m)Kclutter: clutter correction factor

( ) ( )( ) ( ) ( ) ( )clutterfKHKHDK

lossnDiffractioKHKDKKPathLoss

clutterRxeffTxeff

Txeff

++×+

×+++=

65

4321

loglog

loglog

RxeffH

Experimental formulaExperimental formula

ExplanationExplanation

Standard Propagation


Basic Principles and Procedures

Error compliant withrequirements?

Target propagation environment

CW data collection

Measured propagation path loss

Selected propagated environment

parameter setting

Forecast propagation path loss

Comparison

End

Copyright © 2006 Huawei Technologies Co., Ltd. All rights reserved.5m

Site Selection� Criteria for selecting a site

� The antenna height is greater than 20m

� The antenna is at least 5m taller than the nearest obstacle


� Transmitting subsystems

� Transmitting antenna, feeder, high-frequency signal source, antenna

bracketOmni-Antenna

Transmitter

Antenna

bracket

Feeder

Test Platform


� Receiving subsystem

� Test receiver, GPS receiver, test software, portable

PositioningSystem

Data Acquisition System

GPS-Antenna Antenna

Receiver

Test Platform


� Rules of selecting a test path� Landform: the test path must consider all main landforms in the region.

� Height: If the landform is very rugged, the test path must consider thelandforms of different heights in the region.

� Distance: The test path must consider the positions differently awayfrom the site in the region.

� Direction: The test points on the lengthways path must be identicalwith that on the widthways path.

� Length: The total length of the distance in one CW test should begreater than 60km.

� Number of test points: The more the test points are, the better(>10000 points, >4 hours as a minimum)

Test Path


� Rules of selecting a test path

Test Path


Drive Test� The sampling law is meets the Richard Law :40 wavelengths, 50

sampling points

� Upper limit of drive speed: Vmax=0.8λ/Tsample

� The test results obtained in exceptional circumstances must be

removed from the sampling data

� Sampling point with too high fading (more than 30dB) ;

� In a tunnel

� Under a viaduct

� If using a directional antenna for CW test, the test path is selected

from the main lobe coverage area


Test Data Processing� The test data needs to be

processed before being able to be

identified by the planning software.

The processing procedure is:

� Data filtering

� Data dispersion

� Geographic averaging

� Format conversion


Questions

� Which band of radio wave is used for the mobile

communication system?

� What are the two modes of signal fading in the radio

propagation environment? What are their characteristics

and reasons of generation?


Summary� This chapter deals with radio wave. The learning points

include:

� Propagation path of radio wave

� Loss and dispersion characteristics of radio wave, and main

compensation solutions

� Typical radio wave models, main parameters involved

� Methods of correcting radio propagation models



2. Antenna

3. RF Basics



Positions and Functions of Antenna

Lightning protectiondevice

main feeder(7/8“)

Feederclip

Cablingrack

Grounding device

3-connector seal componentinsulation sealing tape, PVC

insulation tape

Antenna adjustment bracket

GSM/CDMAplate-shape

antenna

radio mast (φφφφ50~114mm)

Outdoorfeeder

Indoor superflexible feeder

Feeder cablingwindow

main deviceof BTS

BTS antenna & feeder system diagramBTS antenna & feeder system diagram


omni antenna

AntennaConnector

Dipole

Feed network

AntennaConnector

Feed network

Dipole

Directional antenna

Feed network

Working Principles of Mobile Antenna


Categorize by emission direction

Directional antenna omni antenna

Categories of Antenna


Plate-shape antenna Cap-shape antenna

Whip-shape Paraboloid antenna

Categorize by appearanceCategorize by appearance



Omni antenna Uni-polarizationDirectional antenna

Dual polarizationDirectional antenna

Categorize by polarization modeCategorize by polarization mode



Smart antennaSmart antenna

Smart directional antenna Smart omni-antennaSmart directional antenna



Electric down tilt AntennaElectric down tilt Antenna

Electrical down tilt Antenna



Electric Indices of Antenna


Top view side view

directional antenna direction diagramomni antenna direction diagram

Symmetric halfSymmetric half--wave dipolewave dipole

Antenna Direction Diagram


dBi与与与与dBd

2.15dB

Antenna Gain


Antenna Pattern

Antenna pattern


Antenna Pattern

Side lobeZero point

fillingMain lobe

Max value

Zero pointfilling

Vertical pattern

Backlobe horizontal half-

power angles

Horizontal pattern

Front toback

ratio


Electric downElectric down

tilttilt

Mechanical down tiltMechanical down tilt

Mechanical Down Tilt and Electric Down Tilt


Questions� How are antennas categorized by emission direction, and

by appearance?

� What are electric indices of antenna?

� What are mechanical indices of antenna?

� Into which types does the distributed antenna system break

down?


Summary� Working principles of antenna

� Categories of antenna

� Electric indices of antenna

� Mechanical indices of antenna

� New technologies of antenna



2. Antenna

3. RF Basics



� Absolute power(dBm)

The absolute power of RF signals is notated by dBm and dBW.

Their conversion relationships with mW and W are: e.g., the signal

power is x W, its size notated by dBm is:

For example, 1W=30dBm=0dBW.

� Relative power(dB)

It is the logarithmic notation of the ratio of any two powers

For example：If , so P1 is 3dB greater than P2

Introduction to Power Unit

=

mwmwPWdBmp

11000*lg10)(

=

mWPmwPdBp

2

1lg10)(

wP 21 = wP 12 =


� Noise� Noise means the unpredictable interference signal that occur during

the signal processing (the point frequency interference is notcounted as noise)

� Noise figure� Noise figure is used for measuring the processing capability of the

RF component for small signals, and is usually defined as: outputSNR divided by unit input SNR

NF

SiNiSoNo

Noise-Related Concepts


� Noise figure formula of cascaded network

G1¡ ¢NF1 G2¡ ¢NF2 Gn¡ ¢NFn

Noise-Related Concepts

1211

21

...1...1

−⋅⋅⋅−++−+=

n

ntotal

GGGNF

GNFNFNF


Receiving Sensitivity� Receiving sensitivity

Expressed with power:

Smin=10log(KTB)+ Ft +(S/N), unit: dBmK is a Boltzmann constant, unit: J/K (joule /K) , K=1.38066*10-19 J/K

T represents absolute temperature, unit: °K

B represents signal bandwidth, unit: Hz

Ft represents noise figure, unit: dB

(S/N) represents required signal-to-noise ratio, unit: dB

If B=1Hz, 10log(KTB)=-174dBm/Hz


� Tower Mounted Amplifier

� Enlarge uplink signal, but it’s a loss

for downlink

� Duplexer

� Sharing antenna for receiving and

transmitting

� Sharing antenna for multi-system

RF Components


� Splitter

� Coupler

RF Components


Tx/Rx

Trunk

Trunk

Splitter

TrunkC

oupler

Splitter

Splitter

SplitterSplitter

Splitter

Coupler

Coupler

Splitter

Splitter

Distribution System


Summary� Definition about dBm, dB

� Noise-Related Concepts

� Receiving Sensitivity

� RF Components



2. Antenna

3. RF Basics



Symbol Explanation� Ec

� Average energy per Chip

� Not considered individually, but used for Ec/Io

� Pilot Ec is measured by the UE (for HO) or the Pilot scanner, inthe form of Received Signal Code Power (RSCP)

� For CPICH Ec:� Depends on power and path loss.

� Constant for a given power and path loss. Ec is not dependent onload

� For DPCH Ec:� Depends on power and path loss


Symbol Explanation� Eb

� Average energy per information bit for the PCCPCH, SCCPCH,and DPCH, at the UE antenna connector.

� Typically not considered individually, but used for Eb/Nt

� Depends on channel power (can be variable), path loss, andspreading gain (Gp)

� Constant for a given bit rate, channel power, and path loss

� Can be estimated form Ec and processing gain� Speech 12.2kbps example

� Ec = -80 dBm

� 12.2kbps data rate => Processing gain = 24.98 dB

� Eb~ -80 + 24.98 = -55.02 dBm


Symbol Explanation� Io

� The total received power spectral density, including signal andinterference, as measured at the UE antenna connector.

� Similar to UTRA carrier Receive Strength Signal Indicator(RSSI), at least for practical consideration (SC scanner)

� RSSI in W or dBm

� Io in W/Hz or dBm/Hz

� Measured by the UE (for HO) or Pilot scanner in the form ofRSSI

� Depends on All channel power, All cells, and path loss

� Depends on same-cell and other cell loading

� Depends on external interferences


Symbol Explanation� No common RF definition

� Thermal noise density� Typically not considered individually, but used for Eb/No� Can be calculated

� No = KT– K is the Bolzman constant, 1.38*10^-23– T is the temperature, 290 K

� No = 174 dBm/Hz under typical conditions

� Typically the bandwidth noise and the receiver noise figure arealso considered

� No = KTBNF, where NF is noise figure

� To avoid confusion, NF should be used when referring to thermalnoise


Symbol Explanation� No for WCDMA system

� Total one-sided noise power spectral density due to all noise

sources

� Typically not considered individually, but used for Eb/No

� Defined this way, No and Io are substituted for one another:

� On the uplink the substitution is valid

� On the downlink, differentiating between Noise and Interference is

more challenging


Symbol Explanation� RTWP

� Received Total Wide Bandwidth power

� To describe uplink interference level

� When uplink load increase 50%, RTWP value will increase 3dB

� RSSI

� Received Signal Strength Indicator

� To describe downlink interference level at UE side


Symbol Explanation� RSCP

� Revived Signal Code Power (Ec)

� Ec/Io = RSCP/RSSI, to describe downlink CPICH quality

� ISCP

� Interference Signal Code Power; can be estimated by:

� ISCP = RSSI – RSCP


Summary� Ec, Eb, Io and No

� RTWP, RSSI, RSCP and ISCP

Thank youwww.huawei.com

01 OWJ100001 WCDMA RNP Fundamental (With Comment) ISSUE1

Documents

Transcript of 01 OWJ100001 WCDMA RNP Fundamental (With Comment) ISSUE1