02_RN31543EN10GLA0_Radio Network Planning Fundamentals

7/27/2019 02_RN31543EN10GLA0_Radio Network Planning Fundamentals

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Radio network planning fundamentals

1 © NSN Siemens Networks 3G Radio Planning Essentials / NPO Capability Development

3GRPESS – Module 2



Module 2 – Radio propagation fundamentals

Objectives

• After this module the participant shall be able to:-

• Understand basic radio propagation mechanisms• Understand fading phenomena

• Calculate free space loss


• Understand basic concepts related to base stationend mobile station performance



Module Contents

• Propagation mechanisms

• Multipath And Fading

• Propagation Slope And Different Environments


• ase stat on con gurat on an per ormance

• Base station antenna line configuration

• Mobile station performance



Module Contents

• Propagation mechanisms

– Basics: deciBel (dB)

– Radio channel

– Reflections

– Diffractions

– Scattering




• Base station configuration and performance





deciBel (dB) – Definition

Power

Voltages

dBP

P

Plin

P dB

=

=10 100

10log [ ].

( )

E E dB ( )


E lin= =0og .

P lin.

=E lin.² / 2



deciBel (dB) – Conversion

Calculations in dB (deciBel)• Logarithmic scale

Always with respect to a reference• dBW = dB above Watt

• dBm = dB above mWatt

• dBi = dB above isotropic

• dBd = dB above dipole

-30 dBm = 1 µW

-20 dBm = 10 µW

-10 dBm = 100 µW

-7 dBm = 200 µW

-3 dBm = 500 µW

0 dBm = 1 mW

+3 dBm = 2 mW


• dBµV/m = dB above µV/mRule-of-thumb:• +3dB = factor 2

• +7 dB = factor 5

• +10 dB = factor 10• -3dB = factor 1/2

• -7 dB = factor 1/5

• -10 dB = factor 1/10

+7 m = 5 m

+10 dBm = 10 mW

+13 dBm = 20 mW

+20 dBm = 100mW

+30 dBm = 1 W

+40 dBm = 10W

+50 dBm = 100W



Radio Channel – Main Characteristics

• Linear

– In field strength

• Reciprocal – UL & DL channel same (if in same frequency)

• Dispersive

– In time echo multi ath ro a ation


– In spectrum (wideband channel)

a m pl i t u d e

delay time

direct path

echoes



Free-space propagation

• Signal strength decreases exponentially withdistance

Reflection

Specular reflection

D

Propagation Mechanisms – (1/2)


amplitude A⇒

a*A (a < 1)phase f ⇒ - f

polarisation ⇒ material dependant

phase shift

Diffuse reflection

amplitude A ⇒ a *A (a < 1)

phase f ⇒ random phase

polarisation ⇒ random

specular reflection

diffuse reflection



Propagation Mechanisms – (2/2)

Absorption

• Heavy amplitude attenuation

• Material dependant phase shifts• Depolarisation

A A - 5..30 dB


Diffraction• Wedge - model

• Knife edge

• Multiple knife edges



Scattering – Macrocell

• Scattering local to mobile

– Causes fading

– Small delay and large anglespreads

– Doppler spread causes timevarying effects

• Scattering local to base station

Scattering localto base station


– o a ona opp er sprea

– Small delay and angle spread

• Remote scattering

– Independent path fading

– No additional Doppler spread – Large delay spread

– Large angle spread

Scattering localto mobile

Remote scattering



Scattering – Microcell

• Many local scatterers: Large angle spread

• Low delay spread

• Medium or high Doppler spread




Module Contents

• Reflections, Diffractions And Scattering

• Multipath and Fading

– Delay – Time dispersion

– Angle – Angular Spread

– Frequency – Doppler Spread

– –








Multipath propagation

• Radio signal propagates from A to B over multiple paths usingdifferent propagation mechanisms

– Multipath Propagation

– Received signal is a sum of multipath signals

• Different radio aths have different ro erties


– Distance Delay/Time – Direction Angle

– Direction & Receiver/Transmitter Movement Frequency



Delay – Time dispersion

• Multipath delays due to multipath propagation

– 1 µs ≅ 300 m path difference

• WCDMA Rake receiver to combine multipath components

– Components with delay separation more than 1 chip (0.26 µs = 78 m) can beseparated and combined


– Standardized delay profiles in 3GPP specs:▪ TU3 typical urban at 3 km/h (pedestrians)

▪ TU50 typical urban at 50 km/h (cars)

▪ HT100 hilly terrain (road vehicles, 100 km/h)

▪

RA250 rural area (highways, up to 250 km/h)



P

4.3.2.

1.

1.

2.

=>

Delay Spread

Multipath propagation Channel impulse response


f1

f1

f1

f1

BTS

1st floor

2nd floor

3rd floor

4th floor

Delayed components in DAS

(Distributed antenna systems)



Delay Spread

• Typical values

Environment Delay Spread (µs)

Macrocellular, urban 0.5-3

Macrocellular, suburban 0.5


Macrocellular, rural 0.1-0.2

Macrocellular, HT 3-10

Microcellular < 0.1

Indoor 0.01...0.1



Angle – Angular Spread

• Angular spread arises due to multipath, both from local scatterersnear the mobile and near the base station and remote scatterers

• Angular spread is a function of base station location, distance andenvironment


• Angular Spread has an effect mainly on the performance ofdiversity reception and adaptive antennas



Macrocellular Environment

= Macrocell Coverage Area

Microcell Antenna

Macrocell Antenna

Angular Spread


= Microcell Coverage Area

α αα α

• 5 - 10 degrees in macrocellular environment

• >> 10 degrees in microcellular environment

• < 360 degrees in indoor environment



Frequency – Doppler Spread

• With a moving transmitter or receiver, the frequency observed bythe receiver will change (Doppler effect)

– Rise if the distance on the radio path is decreasing

– Fall if the distance in the radio path is increasing

• The difference between the highest and the lowest frequency shiftis called Doppler spread


f c

vv f d ==

λ

v : Speed of receiver (m/s)

c : Speed of light (3*10^8 m/s)

f : Frequency (Hz)



Fading

• Fading describes the variation of the total pathloss ( signal level)when receiver/transmitter moves in the cell coverage area

• Fading is commonly categorised to two categories based on thephenomena causing it

– Slow fading: Caused by shadowing because of obstacles


– Fast fading: Caused by multipath propagation

• Time-selective fading: Short delay + Doppler

• Frequency-selective fading: Long delay• Space-selective fading: Large angle



power

+20 dB

lognormalfading

Rayleighfading

Fading – Slow & Fast


time2 sec 4 sec 6 sec

mean

value

- 20 dB



Slow Fading – Gaussian Distribution

• Measurement campaigns have shown that slow fading followsGaussian distribution

– Received signal strength in dB scale (e.g. dBm, dBW)

• Gaussian distribution is described by mean value m, standarddeviation σ – 68% of values are within m ±σ


– 95% of values are within m ±2σ• Gaussian distribution used in planning margin calculations



Slow Fading – Gaussian Distribution

Normal / Gaussian Distribution

Standard Deviation, σσσσ = 7 dB

0.05000

0.06000

0.07000

Normal / Gaussian Distribution

22

1

πσ


•d

0.00000

0.01000

0.02000

0.03000

0.04000

-25 -20 -15 -10 -5 0 5 10 15 20 25

µ+σµ+σµ+σµ+σµ−σµ−σµ−σµ−σ



Fast Fading

• Different signal paths interfere and affect the received signal – Rice Fading – the dominant (usually LOS) path exist


– Rayleigh Fading – no dominant path exist



Fast Fading – Rayleigh Distribution

• It can be theretically shown that fast fading follows RayleighDistribution when there is no single dominant multipath component

– Applicable to fast fading in obstructed paths

– Valid for signal level in linear scale (e.g. mW, W)

level (dB)


+

0

-10

-20

-300 1 2 3 4 5 m

920 MHzv = 20 km/h



Fast Fading – Rician Distribution

• Fast fading follows Rician distribution when there is a dominantmultipath component, for example line-of-sight componentcombined with in-direct components

– Sliding transition between Gaussian and Rayleigh

– “Rice-factor” K = r/A: direct / indirect signal energyK = 0 ⇒ RayleighK >>1 ⇒ Gaussian


K = 0(Rayleigh)

K = 1

K = 5



Module Contents




– Free Space Loss


–

– Propagation slope


• Base station antenna line configuration• Mobile station performance



Free Space Loss

• Free space loss proportional to 1/ d 2

– Simplified case: isotropic antenna

– Which part of total radiated power is found within surface A?

– Power density S = P/A = P / 4 πd 2

⇒ Received power within surface A´ : P´ = P/A * A´


– ece ve power re uces w t square o stance

d

Surface A = 4π * d 2

assume surfaceA´= 1m2

2d4d

A´ = 4*AA´´ = 16*A

A

d



Received power with antenna gain

• Power density at the receiving end

• Effective receiver antenna area

• Received power

Reff G A

π λ

4

2

=

ss Gd

PS

24π =

PP

G Gd

r

s

s r =

λ

π 4

2

=


P s

As

G s

P r

Ar

G r

d

er



Propagation slope

• The received power equation can be formulated as

• Where 2

γ −

= d C GGPP r ssr


– C is a constant – γ is the slope factor

▪ Free space γ = 2

▪

Practical propagation γ = 2.5 ... 5

4 = π C



Module Contents










Base station tasks

• WCDMA base station is responsible of

– Common channel generation (Pilot, BCCH etc.)

– Physical layer processing

▪ RF reception

▪ RF transmission

▪ Signal reception, de-spreading (Rake-receiver)


,

▪ Error correction coding/de-coding▪ Data detection

– Fast closed loop power control

– Iub transmission

– Air interface load measurement, reporting to RNC



Base station (RF) configuration options

• The main options for the base station configuration are

– Number of sectors/cells

– Number of carriers per sector – Number of Linear Power Amplifiers

▪ E.g. multiple carriers per Linear Power Amplifiers


– near ower mp er transm t power

– Base band signal processing capacity

▪ Required signal processing capacity depends on maximum number ofconnections and connection type (bit rate)



Base station performance

• Base station performance is related to its capability to transmit andreceive radio signals

• Transmit capability

– Total transmit power

– Transmit losses

• Rece tion ca abilit


– Minimum required signal level = Sensitivity▪ RF performance

▪ Baseband/algorithm performance

• HW Capacity

– Signal processing capacity – Transmission capacity



WCDMA base station transmit power

• In WCDMA base stations the transmit power is shared in cell level between

– All transmitted physical channels (Common channels, Users)

– Carriers, if multiple carriers are used

– Sectors• WCDMA signal requires linear power amplifier (PA)

– Linear modulation (QAM/16-QAM)

– Transmitted si nal sum of multi le si nals


High peak to average ratio• Typical maximum PA output power levels are between 10 and 50 W

• In base station configuration large part of output power can be lost to externalantenna line losses (e.g. 2 – 6 dB) To be minimised

• Physical channel (user) specific maximum power is limited by – Total base station transmit power and amount of DL traffic (DL load)

– Channel specific power limitations defined by the system (In NSN RNC/AC)



WCDMA base station transmit power – HSDPA

• Available DL power can be allocated to HSDPA transmission

– Depends on DL load conditions

– Maximum HSDPA power can be limited by RNC parameters

• Base station transmit power can be fully utilised HSDPA

– No ower control headroom re uired for HSDPA


▪Same power for all users

Maximise DL capacity



WCDMA base station sensitivity

• Base station sensitivity depends on base station reception RF andbase band performance

• Base station reception RF performance is measured by receiver

chain noise figure (NF ) – Base station NF is typically measured at the base station input

– NF describes how much the signal quality (C / I ) is degraded in the receiverchain


– NF is affected by all noise figures, gains and losses in the receiver chain

• Base station reception base band performance in measured byrequired signal quality (E b / N 0 ) for a given connection quality (BER,BLER) – Theoretical limit defined by channel conditions and signal configuration (e.g.

channel coding) – Improvement can be achieved by efficient algorithms, e.g. Rake receiver

performance, and implementation



WCDMA base station sensitivity

• The required received signal power can be calculated when theexternal noise and interference power I EXT is known

NF I E

I C

P EXT b

TOT RX ⋅⋅⋅=⋅=1min


0

)(0

mindB NF I PG I P EXT N

E

TOT I C

RX b ++−=+=



Base station reception performance – E b /N 0

• In order to meet the defined quality requirements (BLER) a certain average bit-energy divided by total noise+interference spectral density (E b / N 0 ) is needed

– E b / N 0 is defined at bit detection in the receiver baseband

• E b / N 0 depends on – Service and bearer

▪ Bit rate, BER requirement, channel coding

– Radio channel


▪ Doppler spread (Mobile speed, frequency)

▪ Multipath, delay spread

– Receiver/connection configuration

▪ Handover situation

▪ Diversity configuration

▪Fast power control usage

– Typically given E b / N 0 includes also overhead due to physical layer control signalling

▪ Higher bit rates Less overhead Lower E b / N 0

R i d E /N



Required E b /N 0

PG

I

C

R

W

I

C

N

E b ⋅=⋅=0

−

Energyper chip

Total powerspectral density


N othown DL N othownUL

Where:C = received powerR = bit rate (typically service bit rate)W = bandwidth

PG = processing gainIown = total power received from the serving cell (excluding own signal)Ioth = total power received from other cellsPN = noise powerα = orthogonality factor

R i d UL E /N S ifi ti d NSN



Required UL E b /N 0 – Specifications and NSN

• Specification requirements for UL for different

– Speeds

– Services

– Channel conditions▪ 3GPP models

• With 2-port UL antenna


v y

• Fast closed loop powercontrol used

• Include some NSN

corrections forimplementation margin,effect of speed, power controletc.

REF: Dimensioning and Configuring WCDMA RAN, dn0450427x4x0xen

R i d UL E /N HSUPA



Required UL E b /N 0 - HSUPA

• New set of Eb/No figures generated fromlink level simulations

– Include the E-DPDCH, E-DPCCH andDPCCH

• Eb/No values are included for

– Bit rates 32 kbps to 1920 kbps

– Target BLER 1, 5 and 10 %

Eb/No look-up tables


– Propagation channels Pedestrian A 3

km/h and Vehicular A 30 km/h

• Target BLER figures are applicable toeach MAC-e transmission

– 10 % Target BLER corresponds to aBLER of 0.01 % after 4 transmissions

Required E /I



Required Ec /I0

• Required E c /I 0 is the required RF C/I needed in order to meet thebaseband E b / N 0 criteria

– E c /N 0 used often instead of E c /I 0 in same context

– NOTE: Pilot E c /N 0 different measure

• E c / I 0 depends on the bit rate and E b / N 0

Ener


I

C

W

R

N

E

I

E bc =⋅=00

per chip

Total powerspectral density

Base station performance in different frequency bands



Base station performance in different frequency bands

• The specification requirements for base station sensitivity and transmit power issame in all frequency bands

OperatingBand

UL FrequenciesUE transmit, Node B receive

DL frequenciesUE receive, Node B transmit

I 1920 – 1980 MHz 2110 –2170 MHz

II 1850 –1910 MHz 1930 –1990 MHzIII 1710-1785 MHz 1805-1880 MHz

IV 1710-1755 MHz 2110-2155 MHz

V 824 – 849 MHz 869-894 MHz

VI 830-840 MHz 875-885 MHzVII 2500-2570 MHz 2620-2690 MHz


• In reality we will have some changes on our overall performance via frequencychange: – Node B noise figure (e.g. Flexi ~2 GHz ≈ 2 dB, ~900 MHz ≈ 2.3 dB),

– Node B antenna gain, same size (e.g. ~2 GHz =17.5 dBi, ~900MHz = 14.5 dBi),

– Cable loss (e.g. ~2 GHz = 5.9 dB/100 m, ~900MHz = 3.7 dB/100 m),

– User equipment noise figure, specification (e.g.~2 GHz ≈ 8 dB, ~900 MHz ≈ 11 dB) – Propagation, lower frequency has better propagation performance. Thus carrier

frequency is affecting a lot on cell range calculations.

VIII 880 – 915 MHz 925 – 960 MHz

IX 1749.9-1784.9 MHz 1844.9-1879.9 MHz

Base station HW capacity



Base station HW capacity

• Base station HW capacity can be limited by signal processing andtransmission capacity

• Signal processing capacity is shared between all users and

common control channels under the same base stations – In NSN base stations the main signal processing capacity unit is a Channel

element


– anne e emen correspon s s gna process ng power requ re or a speec

call (<16 kbit/s)▪ Includes both transmit and receive processing (DL & UL)

– Different connections/services require different number of Channel elements

▪ speech 1 channel element

▪ 64kbit/s service (RT or NRT) 4 channel elements▪ 128kbit/s service (RT or NRT) 4 channel elements

▪ 384kbit/s service (RT or NRT) 16 channel elements

▪ HSDPA (5 codes) 32 channel elements

Module Contents



Module Contents








Antenna System



Antenna System

• The WCDMA UltraSite Antenna Systemcontains the following components

– Antennas

– WCDMA Masthead Amplifiers (MHA)

– Bias-T

– EMP Protector, lightning protection (onlyneeded if no Bias-T is used)


– p exers

▪ combines/divides two bands such asWCDMA and GSM to a common feeder line)

– Triplexers

▪ combines/divides three bands such asWCDMA, GSM1800 and GSM900 to a

common feeder line) – Feeder and Jumper cables, Grounding kits

Antenna types



Antenna types

• Vertical polarised antennas and cross-polarised antennas

• Omni-directional and 33/65/88 degree antennas

• WCDMA/GSM dual-band antennas (e.g. GSM900 & WCDMA2100)

– Separate element for both bands, separate tilt possible – Separate or common antenna connectors (internal duplexer)

• WCDMA/GSM broadband antennas (e.g. GSM1800 & WCDMA2100)

–


– Single element and connector for multiple bands, same tilt• WCDMA/GSM triple-band antennas (e.g. GSM900&1800 & WCDMA2100)

• Smart Radio Concept (SRC) antennas

– Antennas with two wideband X-pol elements

• Electrically tilted antennas

Antenna structures – Dual/single band



Antenna structures Dual/single band

• Two separate antenna arrays in dual-band antenna

– 900 MHz & 1800 MHz

– Different element sizes

Dual Single


Antenna specification



Antenna specification

• Gain

– Antenna gain is proportional to the physical size, signal frequency and antennavertical and horizontal beamwidth▪ Large size & High frequency Narrow beam High gain

– In WCDMA2100 typical gains are between 12 dBi 20 dBi• Horizontal beamwidth

– Selection of horizontal frequency depends mainly on number of sectors▪ Omni directional = 360 degrees


▪ 3-sectors = 60 – 90 degrees

▪ 6-sectors = 30 degrees

• Vertical beamwidth

– Vertical beamwidth depends on the vertical dimension of the antenna▪ 2 m 4.3 degrees 19.5 dBi, 1.3 m 6.7 degrees 18.5 dBi, 0.34 m 28 degrees

12.3 dBi

– Narrow beamwidth antennas have higher gain and also tilting has more effect

• Electrical downtilt

– Downtilt improves the dominance of the cell (more in coverage and capacityenhancement)

WCDMA Panels



WCDMA Panels

WCDMA Broadband Antennas

Antenna Type Dimensions[mm]

Weight[kg]

FrequencyRange [MHz]

Gain[dBi]

BeamWidth

Downtilt

CS72761.01 Xpol F-panel 342/155/69 2.0 1710-2170 12.5 65° 2°

CS72761.02 X ol F- anel 1302/155/69 6.0 1710-2170 18.5 65° 2°


CS72761.05 Xpol F-panel 1302/155/69 7.5 1710-2170 17 88° 0°...8°

CS72761.07 Xpol F-panel 1942/155/69 10.0 1710-2170 19.5 65° 0°...6°

CS72761.08 Xpol F-panel 662/155/69 7.5 1710-2170 18 65° 0°...8°

CS72761.09 Xpol F-panel 1302/155/69 3.5 1710-2170 15.5 65° 0°...10°

WCDMA Panels



WCDMA Panels

WCDMA Narrowbeam Antennas

WCDMA Dual Broadband Antennas (WCDMA/GSM 1800 or SRC)

Antenna TypeDimensions

[mm]

Weight

[kg]

Frequency

Range [MHz]

Gain

[dBi]

Beam

WidthDowntilt

CS72764.01 Xpol F-panel 1302/299/69 12.0 1710-2170 18.5/18.5 85°/85° 0..8°/0°..8°

CS72761.09 Xpol F-panel 1302/299/69 12.0 1710-2170 17/17 65°/65° 0..8°/0°..8°


Antenna Type

[mm]

[kg]

Range [MHz]

[dBi]

WidthDowntilt

CS72762.01 Xpol F-panel 1302/299/69 12 1900-2170 21 30° 0°...8°

WCDMA Omni Antennas

Antenna Type

Dimensions

[mm]

Weight

[kg]

Frequency

Range [MHz]

Gain

[dBi]

Beam

Width Downtilt

CS72760 Omni 1570/148/112 5.0 1920/2170 11 360° --

WCDMA panels in different frequency bands



p q y

• BTS antenna gain is lower in WCDMA900 than in WCDMA2100 ifthe antenna physical sizes are kept the same

– Vertical size limiting Vertical beam width increases when frequency

decreases


Upgrades to Current GSM Antennas



pg

spacediversity

space+

polarization

diversity

1 3 0 0

mm

150 mm 150 mmUpgradeCurrent


polarizationdiversity

2 xpolarization

diversitywithin

one radome

260 mm

Space diversity improves performance 0.5..1.0 dB compared to single radome.The gain of 2.5 dB assumes single radome.

Mast Head Amplifier



-119 dBm / 200 kHz

Passive Intermodulation Products

PIM level in RX band

+/- 0.5 dB room

+/- 0.9 dB all tempsInsertion Loss 0.6 dB

Response, other freqs0 dB within 20 MHz of

passband

3rd-order intercept 10 dBm

MHA Input Dynamic Range

Nominal gain of 12 dB

Gain, RX band

Ripple

p

Improves base station system noise figure

Technical Data Sheet:

TX

RX


- m z

ANT port in-band 5 dBmout-of-band 20 dBm

BTS port avg 46 dBm in-band

peak 62 dBm in-band

65 dB

71 dB

65 dB

200 - 300 mA

100 msec

UMTS RX, 1920-1980

Alarm Setting Conditions

Alarm current range

Switch time

Critical Input RX filter rejections

Critical TX filter rejections

UMTS TX, 2110-2170

GSM1800, 1805-1880

PIM level in TX band

Rated Power at Ports

1dB compression -5 dBm

Noise Figure 2 dB

RX band 16 dB

TX band 18 dB

Group delay distortion 20 ns over 5 MHZ

7.0 - 8.6V, UltraSite/MetroSite

11 - 13 V , CoSited BTS

Nominal current 190 mA

Max. current 350 mA

Insertion Loss 3 dB

Return Loss 12 dB

Voltage

Return Loss, ANT and BTS ports

Bypass Mode

DC Power supplied

Bias-T



• Function

– Provides DC power for MHA through feederline

– Lightning protection

• Features – Fault monitoring of MHA and Antenna line

– Fowards alarms to WAF

– Low insertion loss (<0.3dB)

Insertion loss 0.3 dB

Return loss 18 dB

Rated power 55 W avg, 2.2 kW peak

7 dB nominal+/- 2 dB tolerance

no alarm: 0 V, 50 mA max

alarmed : 3.3V, 0 mA

Response time 0.5 sec

RF Performance

Alarm Signal

VSWR alarmthreshold

Logic


– Can be installed on mast or in any WCDMA

UltraSite cabinet

Alarm indicates:no RF power, high VSWR (no

DC power implied)

Voltage drop 0.5 V

Rated power 7.5 - 9.1V, 350 mA max

DC supply via: RJ-45 from BTS

Ins loss @ 1 MHz 3 dB

DC and Signal

Diplexers / Triplexers



RF Performance

• Unit types – NSN Triplexer Unit

– NSN GSM 900 / WCDMA Diplexer Unit

– NSN GSM 1800 / WCDMA Diplexer Unit

• Selectable DC pass function in each unit• Technical Data Sheet:


GSM 900 BTS

GSM 1800 BTS

WCDMA BTS

nsert on oss,

Port - Common

Isolation, port to

port

Return Loss, any

port

GSM RX band

GSM 120 W avg 1.44 kW peak

UMTS 55 W avg 2.15 kW peak

-116 dBm

Rated Power at Ports

Passive Intermodulation

0.3 dB

50 dB

>18 dB

NSN Triplexer

Feeders



• Feeders cause most of the losses in base station antenna system

• Higher diameter feeders are selected for antenna lines with long feeder lengths

Single Repeated

Attenuation@ 2170 MHZ

[dB/100m]

Min Bending Radius [mm]Feeder Type

Diameter

[inch]

Weight

[kg/m]


• Feeder losses decrease when frequency is lower

– 7/8” loss at 900 MHz is about 3.7 dB/100 m

CS72251 1/2 0.35 80 160 11.9

CS72252 7/8 0.55 120 250 6.52

CS72254 1 1/5 1.45 250 500 4.05

Antenna system performance – Summary



• The base station antenna system has a significant effect on theperformance of the base station

• The main parameters affecting the base station antenna system

performance – Antenna gain and radiation pattern

Maximum gain to power budget


– Feeder and connector losses

Feeder loss to power budget

– Usage of antenna diversity

Effect on power budget E b / N 0

– Usage of MHA, effect to receiver system noise figure

Noise figure improvement to power budget (See Capacity and Coverageimprovement)

• Frequency band affects antenna line performance

Module Contents










Mobile station performance



• In network planning an average mobile station performance haveto be assumed due to random UE type population

• Mobile station performance is related to its transmission and

reception performance – Antenna TX/RX gain

▪ Typically assumed to be 0 – 2 dBi


– Transmission power classes

▪ Power Class 4 most common at the moment (note ± 2 dB tolerance)

Mobile station performance



• Reception performance depends on UE noise figure and E b / N 0

requirement

– Typically noise figure is assumed to be

▪8 dB in Band I, 11 dB in Band VIII and so on

Operating Band Unit DPCH_Ec <REFSENS>

I dBm/3.84 MHz -117


II dBm/3.84 MHz -115

III dBm/3.84 MHz -114

IV dBm/3.84 MHz -117

V dBm/3.84 MHz -115

VI dBm/3.84 MHz -117

VII dBm/3.84 MHz -115VIII dBm/3.84 MHz -114

IX dBm/3.84 MHz -116

Mobile station performance – Required DL E b /N 0



• DL sensitivity requirements from specifications (3GPP 25.101) fordifferent

– Speeds

– Services – Channel conditions

▪ 3GPP models


• With fast closed loop power

control

• Include some NSNcorrections forimplementation margin,effect of speed, power controletc. REF: Dimensioning and Configuring WCDMA RAN, dn0450427x4x0xen

Mobile station performance – HSDPA



• SINR is used instead of E b / N 0 in HSDPA performance evaluation

– Modulation and coding Bit rate can be changed every 10 ms

• Definition of HS-DSCH SINR:

– Narrowband signal-to-interference-plus-noise-ratio after despreading of the

HS-PDSCH

– SINR includes the SF16 rocessin ain for the HS-PDSCH and the effect


of using orthogonal codes

• Average HS-DSCH SINR:

– This is the experienced HS-DSCH SINR by a user average over fast fading.

– The average bit rate for a single HSDPA-user can be expressed as a

function of the average HS-DSCH SINR, for a given number of HS-PDSCHcodes

Required SINR



PDSCH HS SF I

C

SINR −⋅=


N othown DL −=

Where:C = received powerIown = total power received from the serving cell (excluding own signal)Ioth = total power received from other cells

PN = noise powerα = orthogonality factorSFHS-PDSCH = Spreading factor on HSDPA (= 16)

Relation Between avg. SINR and HSDPA Throughput



• The single-user HSDPAthroughput versus itsaverage HS-DSCH SINR

is plotted.• Notice that these results

include the effect of fast h r o u g h p u t [ M b p s ]

2.5

3.0

3.5

4.0

HS-DSCH POWER 7W (OF 15W), 5 CODES,1RX-1TX, 6MS/1DB LA DELAY/ERROR

Rake, Ped-A, 3km/h

Rake, Veh-A, 3km/h

Rake, Ped-B, 3km/h

MMSE, Ped-A, 3km/h

MMSE, Ped-B, 3km/h

ACTIVITY FACTOR 100%


-DSCH link adaptation.

• An average HS-DSCHSINR of 23 dB is requiredto achieve the maximumdata rate of 3.6 Mbps with

5 HS-PDSCH codes. A v

e r a g e s i n g l e - u

s e r

Average SINR (1 HS-PDSCH) [dB]

0.5

1.0

1.5

2.0

-10 -5 50 10 15 20 25 300

a e, e - , m

Average HS-DSCH SINR [dB]

Module 2 – Radio Propagation Fundamentals



Summary

• Radio signal propagates with multiple propagation mechanisms

• Radio signal strength varies between locations Fading

• Fading is caused by shadowing and multipath propagation• Received radio signal power attenuates with increasing distance Propagation slope


• ase s a on per ormance s measure y

– Transmit capability – Reception capability

– HW capacity

02_RN31543EN10GLA0_Radio Network Planning Fundamentals

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