HSDPA Link Budget Presentation v1%2E09

2 Nortel Confidential Information

HSDPA Link Budget Presentation

Core WNE, 22nd June 2006


Agenda

Uplink Link Budget

Downlink Link Budget

HSDPA Throughput


> Uplink Link Budget


Uplink Link Budget

BS

BSUE S -GSlantloss-Cableloss -G Tx LossPath ReverseMax UE

> Aim: UL capacity and Max Available Path Loss

• UL capacity thanks to N-pole Formula• Cell Size with Cost Hata model

> Same parameters as R’99 link budget except BS Eb/No • Frequency : 1980Mhz• Environment : Dense Urban, Urban, Suburban, Rural• Services : Speech 12.2, CS 64, PS 64, PS 128• BTS : Noise Figure, Antenna Gain,• UE : Noise Figure, UE Power • Margin / loss : Shadow Margin, penetration loss, body loss, cable & connectors loss, slant loss• For more information about R’99 Link budget see the guidelines at this link : http://navigate.us.nortel.com/imds?pg=/eng/wne/umts/acc/rf/lb

Margins - PathLoss ReverseMax PathLoss Reverse Available

Uplink Link Budget

General CS 64

RX Frequency band (MHz) 1980 TX Frequency band (MHz) 2170 Spreading bandwidth (kHz) 3840 Thermal noise (kTB) (dBm) -108.2 Data rate (kb/s) 64.0 Processing gain (dB) 17.8

BS RX Eb/No (dB) 4.2 dB Thermal noise (kTB) (dBm) -108.2 dBm BS RX noise figure (dB) 2.5 dB BS RX sensitivity (dBm) -119.7 dBm BS RX antenna gain (dBi) 17.0 dBi

Maximum UE TX power (dBm)/MEAN 21.0 dBm UE TX antenna gain (dBi) 0.0 dBi Total UE TX EIRP (dBm) 21.0 dBm BS RX cable & connector losses (dB) 3.0 dB Slant losses (dB) 1.5 dB Maximum allowable isotropic path loss (dB) 153.2 dB

Area Reliability 90% Total Standard Deviation 13.3 dB Shadowing Margin 5.2 dB Penetration Factor 18.0 dB UL Interference margin due to traffic loading (dB) 3.0 dB Body loss (dB) 1.0 dB Reverse Total required margin (dB) 27.2 dB

Available Reverse Link Budget (dB) 126.0 dB Capacity Activity factor 1.0 Frequency reuse efficiency 0.6 UL loading factor (%) 50% Eb/No gain due to diversity with SHO 1.0 dB Pole capacity per sector (# of links) 20.0 UL Capacity per sector (# of links) 10.0 Troughput (kbps) 639.4 Cell dimensioning Site antenna height (m) 30.0 Propagation coefficient 35.2 Path loss at 1 km 137.6 Selected environment correction 0.0 Maximum coverage range (km) 0.47 km Area covered by 1 Site (km²) 0.43 km²

TMA No


Node B performance : Eb/No

>HS-DPCCH impact

DPDCHn I

j

cd,1 d

Sdpch,n

I+jQ

DPDCH1

Q

cd,3 d

cd,2 d

DPDCH2

cc c

DPCCH

S

chs

HS-DPCCH (If Nmax-dpdch mod 2 = 1)

chs

HS-DPCCH (If Nmax-dpdch mod 2 = 0)

hs

hs

cd,6 d

DPDCHn+1

222

22

log10LOSShscd

cd

22

1*c

hs

c

dDPCCHPerMaxUETxPow

222

22

222

22

log*10)()(

*

hsdc

dcDCH

hsdc

dcDCH

dBerMaxUETxPowdBP

erMaxUETxPowP

222

2

1*hsdc

hs

DPCCHHS

erMaxUETxPow

PerMaxUETxPow

>The maximum UE TX power deduced

>So the DCH available power is:

And

>The loss in performance is given by the following formula:

See 3GPP TS25.213


>HS-DPCCH impact

•Eb /No loss due to HS- DPCCH:

• iCEM

More repetitions less losses

•QoS• HS-DPCCH : 4% BLER on ACK/NACK and CQI• Speech : 10-1 BLER• PS64/128/384: 10-1 BLER

Loss (dB)

Speech 1.5

CS 64 1.3

PS 64 1.3

PS 128 0.6

PS 384 0.3

lossN

E

N

E

RiCEM

b

HSDPA

b

99'00

Node B performance : Eb/No


> The N-pole formula gives the maximum number of channels that the radio can carry:

• PG is the processing gain• FR is the frequency reuse efficiency • V is the activity factor• Eb/N0 is the UL performances requirements• GSHO is the gain obtained on the Eb/N0 due to uplink • selection diversity when doing soft/softer handover

> Assumptions :• Pedestrian A @3km/h• FR = 60 % • GSHO = 1 dB

Service

Without HSDPA

With HSDPA

PS 64 12 10

PS 128 7 6

PS 384 3 3

Real capacity – 50% loaded cell

SHO0

bpole

.

PG.FR1

GN

EV

N

HSDPA impact on the N-pole capacity


> Downlink Link Budget



> Aim : Power allocated to HSDPA traffic

Max Available

Reverse PathlossMax Down-Link Pathloss

PA Dimensioning

(% of PA for

Common Channels,

traffic channels)

HSDPA Traffic

Power

HSDPA Throughput



Max Available Reverse PathlossMax Down Link Pathloss =

Available Reverse Pathloss + Frequency shift UL/DL + Penetration factor + Body Loss

+ Slant loss + Cable/feeders loss + Shadow margin – BS Antenna Gain

PA DDM

TMA

BS Antenna Gain

Tx Cable Loss

Node B

Max available Air interface pathloss given by UL link Budget

Penetration Losses

PA power at PA output connector

Body Loss

UE Antenna Gain

UE Rx Sensitivity

Shadow MarginMean Path loss

Measured Path loss

PA DDM

TMA

BS Antenna Gain

Tx Cable Loss

Node B

Max available Air interface pathloss given by UL link Budget

Penetration LossesPenetration Losses

PA power at PA output connector

Body Loss

UE Antenna Gain

UE Rx Sensitivity

Shadow MarginMean Path loss

Measured Path loss



Max Available Reverse PathlossMax Down Link Pathloss =

Available Reverse Pathloss + Frequency shift UL/DL + Penetration factor + Body Loss

+ Slant loss + Cable/feeders loss + Shadow margin – BS Antenna Gain

Uplink Link Budget

General CS 64

RX Frequency band (MHz) 1980 TX Frequency band (MHz) 2170 Spreading bandwidth (kHz) 3840 Thermal noise (kTB) (dBm) -108.2 Data rate (kb/s) 64.0 Processing gain (dB) 17.8

BS RX Eb/No (dB) 3.8 dB Thermal noise (kTB) (dBm) -108.2 dBm BS RX noise figure (dB) 2.5 dB BS RX sensitivity (dBm) -119.7 dBm BS RX antenna gain (dBi) 17.0 dBi

Maximum UE TX power (dBm)/MEAN 21.0 dBm UE TX antenna gain (dBi) 0.0 dBi Total UE TX EIRP (dBm) 21.0 dBm BS RX cable & connector losses (dB) 3.0 dB Slant losses (dB) 1.5 dB Maximum allowable isotropic path loss (dB) 153.2 dB

Area Reliability 90% Total Standard Deviation 13.3 dB Shadowing Margin 5.2 dB Penetration Factor 18.0 dB UL Interference margin due to traffic loading (dB) 3.0 dB Body loss (dB) 1.0 dB Reverse Total required margin (dB) 27.2 dB

Available Reverse Link Budget (dB) 126.0 dB Capacity Activity factor 1.0 Frequency reuse efficiency 0.6 UL loading factor (%) 50% Eb/No gain due to diversity with SHO 1.0 dB Pole capacity per sector (# of links) 20.0 UL Capacity per sector (# of links) 10.0 Troughput (kbps) 639.4 Cell dimensioning Site antenna height (m) 30.0 Propagation coefficient 35.2 Path loss at 1 km 137.6 Selected environment correction 0.0 Maximum coverage range (km) 0.47 km Area covered by 1 Site (km²) 0.43 km²

TMA No

PA Dimensioning

(% of PA for

Common Channels,

traffic channels)


General Body loss (dB) 1 dB BS RX antenna gain 17 dB BS TX cable & connector losses (dB) 3 dB Penetration Factor 18 dB Slant loss (dB) 1.5 dB Shadowing Margin 5.2 dB Frequency Shift UL/DL 1.3 dB Coupling loss 1.3 dB Additive DL Loss/UL Air interface 14.3 dB BS RX noise figure 3 dB BS Transmitter Power (W) 45.0 W BS Transmitter Power (dBm) 46.5 dBm Orthogonnality Factor 0.15 MS Noise Figure 7. dB Noise Spectral Density (dBm/Hz) -167.0 dB MS Thermal noise -101.2 dBm Out-of-Cell to In-Cell Interf. Ratio (f) at 90% 190% CPICH Ec/ Io Target at 90% -15 dB I i = Interference intracell -93.8 dBm Ie = Interference intercell -91.0 dBm CPICH Power 36.4 dBm CPICH Power ratio 10.3% HS-SCCH relative to P-CPICH 0 dB Com. Control Channels Power (d) including CPICH 35.6% HS-PDSCH Power ratio 64.4% DCH Power ratio 0.0% Max UL Air interface Path Loss 126.0 dB Max DL Path Losses (from PA to UE antenna connector) 140.3 dB

+


CQI Offset

HS-SCCH/CPICH (dB)

1 – 7 0

8 – 9 -3

10 – 12 -5

13 – 30 -8

> PA Dimensioning• We set the CPICH target, typical value = -15 dB . • HSDPA adds a new common channel: the HS-SCCH that impacts the PA dimensioning and therefore the ratio

of PA for the traffic. The main goal of downlink link budget is to determine the allocated power HS-SCCH and therefore the available power of traffic channels.

• We set the HS-SCCH power relative to the CPICH as it is done for common channels • At the beginning the HS-SCCH power relative is set to 0.

PA Dimensioning

Relative to Power (W) Time P-CPICH(dB) multiplexed

PA Power ---- 45.0 W P-CPICH ---- 4.4 W 4.4 W P-SCH -5.0 dB 1.4 W ---- S-SCH -5.0 dB 1.4 W ----

P-CCPCH -2.0 dB 2.8 W 2.8 W S-CCPCH -3.0 dB 2.2 W 2.2 W

PICH -5.0 dB 1.4 W 1.4 W AICH -7.0 dB 0.9 W 0.9 W

HS-SCCH 0.0 dB 4.4 W 4.4 W

Power allocated to common 16.0 W

Common/PA Ratio (included HS-SCCH) 35.6%

%(DCH+CCH) for DCH Margin 0.0 W

Power allocated to HSDPA traffic channel 29.0 W

Power allocated to R99 traffic channel 0.0 W

Power allocated to traffic channel 29.0 W

Traffic/ PA Ratio 64.4%

HSDPA Traffic

Power



> HSDPA Throughput


HSDPA Throughput – C/I formula

HSDPA Traffic

Power

C/I CQI Throughput

With:• DL_PL is downlink path loss• Pth is the thermal noise (=INoise)• Ptraffic_HSDPA is the HS-PDSCH power, HDPA traffic power• RxDivGain is the UE Rx diversity gain • n is the number of code used• α is the orthogonallity loss factor• PA is total power of BTS

• Ie is equal to :

yGainRxDiversit*PL_DL*P

yGainRxDiversit*PA*

Ii

I)

n

PPA(*

P

I

C

theHSDPA_Traffic

HSDPA_Traffic

11

PL_DL

PA*

I

II*

I

II

i

ei

i

ee


CQI according to C/I(dB)

5

10

15

20

25

30

-10 -5 0 5 10 15

C/I (dB)

CQ

I

CQI - category 6

CQI - category 10

CQI - category 12

HSDPA Traffic

Power

C/I CQI Throughput

C/I

CQI = 8

CQI

Throughput @ cell edge = 288 kbps

CQI mapping table for UE categories 6

Number of

CQI value Transport Block Size

# MAC-d PDUs

per TrBlk RLC Throughput per HS-

PDSCH HS-PDSCH Modulation

0 N/A Out of range

1 137 0 0 kbps 1 QPSK

2 173 0 0 kbps 1 QPSK

3 233 0 0 kbps 1 QPSK

4 317 0 0 kbps 1 QPSK

5 377 1 144 kbps 1 QPSK

6 461 1 144 kbps 1 QPSK

7 650 1 144 kbps 2 QPSK

8 792 2 288 kbps 2 QPSK

9 931 2 288 kbps 2 QPSK

10 1262 3 432 kbps 3 QPSK

11 1483 4 576 kbps 3 QPSK

12 1742 5 720 kbps 3 QPSK

13 2279 6 864 kbps 4 QPSK

14 2583 7 1008 kbps 4 QPSK

15 3319 9 1296 kbps 5 QPSK

16 3565 10 1440 kbps 5 16-QAM

17 4189 12 1728 kbps 5 16-QAM

18 4664 13 1872 kbps 5 16-QAM

19 5287 15 2160 kbps 5 16-QAM

20 5887 17 2448 kbps 5 16-QAM

21 6554 19 2736 kbps 5 16-QAM

22 7168 21 3024 kbps 5 16-QAM

23 7168 21 3024 kbps 5 16-QAM

24 7168 21 3024 kbps 5 16-QAM

25 7168 21 3024 kbps 5 16-QAM

26 7168 21 3024 kbps 5 16-QAM

27 7168 21 3024 kbps 5 16-QAM

28 7168 21 3024 kbps 5 16-QAM

29 7168 21 3024 kbps 5 16-QAM

30 7168 21 3024 kbps 5 16-QAM

See: 3GPP TS25.214


yGainRxDiversit*PA*

Ii

I)

n

PPA(*

P

I

C

theHSDPA_Traffic

HSDPA_Traffic

11

CQI = 8

HSDPA Throughput @ cell edge


Ie/Ii according to DL PL - Dense Urban environment A

0%

20%

40%

60%

80%

100%

120%

140%

160%

180%

200%

60 dB 80 dB 100 dB 120 dB 140 dB 160 dB

Down Link Pathloss (dB)

Ie/I

i (%

)

CQI according to C/I(dB)

5

10

15

20

25

30

-10 -5 0 5 10 15

C/I (dB)

CQ

ICQI - category 6

CQI - category 10

CQI - category 12


yGainRxDiversit*PA*

Ii

I)

n

PPA(*

P

I

C

theHSDPA_Traffic

HSDPA_Traffic

11

C/I

CQI =19

Cell Throughput = 2160 kbpsDown Link Pathloss

Ie/Ii

Down Link PathlossDistance Up Link Pathloss

CQI =19

HSDPA Throughput in the cell


Multi-user gain

> Two different contributions increase the Multi-user gain (MUG):• The number of users scheduled per TTI: TTI_MUG• The scheduler strategy: Scheduler MUG

> There are several scheduler strategies:• Round-Robin• Proportional Fair • Max-Rate

> Multi-users scheduling per TTI• 1 or 2 HS-SCCH required• Tradeoff: one HS-SCCH per cell limits cell throughput (only one UE is

scheduled in each TTI=2ms) but increase the available power for the HS-DSCH =>higher throughput

• A second user is scheduler if there is still some unused power available (power adjustment used for the 1st user)


Multi-user gain: TTI_MUG

> TTI_MUG is dependent on:• The available power for HSDPA traffic• The Maximum allowable HSDPA power per user, defined by the

MPO (measurement power offset)

> The MPO restricts the power used by the first user, to schedule a second user with the remaining power, this results in:• A higher cell throughput.• A higher user throughput as the number of users per TTI is

increased (for a constant number of HSDPA active users in the cell).• Even if the first user receives less power, the throughput is not

necessary degraded, in good radio conditions. Typically, used with a proportional fair scheduler, the two users scheduled with TTI MUG should benefit from high throughputs.


Multi-User gain: Scheduler gain

User 2 scheduled User 1 scheduled

A user is not scheduled if in deep fading !

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2-35

-30

-25

-20

-15

-10

-5

0

5

Time (sec)F

as

t F

ad

ing

am

plit

ud

e (

dB

)

Proportional Fair Scheduling principle

User 1User 2

> Transmitting to users with favorable short term radio conditions can increase significantly the throughput compared to a Round-Robin scheduler.

> The scheduler MUG increases as the cell load increases. Indeed, the probability to have one user with very good radio conditions varies with the number of active HSDPA users in the cell.


Scheduler MUG & Rx Diversity

0 5 10 15 20 25 300

20

40

60

80

100

120Multi-User Gain - Single - 3 km/h

#users per cell

MU

G %

1 RX2 RX

0 5 10 15 20 25 300

10

20

30

40

50

60

70

80Multi-User Gain - Pedestrian_a - 3 km/h

#users per cell

MU

G %

1 RX2 RX

> The MUG decreases when • The #RX antennae increase• The UE speed increases• The channel profile delay spread

increases

> Proportional fair is up to 100% gain over the Round-Robin.

> Link Budget assumption : 20 simultaneous users per cell


Scheduler MUG & Rx Diversity

> The mean user throughput decreases with the #users but not linearly thanks to MUG (Multi-User Gain).

> RX diversity offers 15-20% extra again • 1 Rx diversity : 1 antenna• 2 Rx diversity : 2 antennas

0 5 10 15 20 25 300

200

400

600

800

1000

1200

1400

1600

1800

2000

#users per sector

Me

an

us

er

thro

ug

hp

ut

(kb

/s)

Mean User Throughput vs. #users Single - 3 km/h - UE category 6

1 RX2 RX

0 5 10 15 20 25 300

200

400

600

800

1000

1200

1400

1600

1800

2000

#users per sector

Me

an

us

er

thro

ug

hp

ut

(kb

/s)

Mean User Throughput vs. #users Pedestrian_a - 3 km/h - UE category 6

1 RX2 RX


HSDPA Throughput – RLC/MAC

> MAC-d SDU size is 336 bits (320 bits of payload and 16 bits of header) so the number of SDU per transport block size is:

> The RLC Throughput per HS-PDSCH value in bps is:

> With TTI is 2 ms and PDU size is 320 bits and BLER = 10 %

)size_SDU_dMac

size_block_Transport(round_floorSDU_NB

TTI

size_PDU*SDU_NBThroughput_RLC

BLER*TTI

size_PDU*SDU_NBThroughput_RLC 1


Betas settingDefault values

> The values are set per RAB, compliant with the 3GPP specifications 25.213.

> Different power offset recommendations for the CQI and ACK/NACK

RAB CS 12.2 kb/s PS 64 kb/s PS 128 kb/s PS 384 kb/s

Beta d1 1 1 1

Beta c11/15 8/15 5/15 3/15

Beta hs/Beta c

CQI

1 1 1 1

Beta hs/Beta c

ACK/NACK

19/15 19/15 19/15 19/15

HSDPA Link Budget Presentation v1%2E09

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