Ibs Lte Design

(1)

HUAWEI TECHNOLOGIES CO., HUAWEI TECHNOLOGIES CO., LTDLTD

IBS LTE Design

Li Youfu/00192732 Li Youfu/00192732

(2)

Huge deploy workload of dual-DAS Huge deploy workload of dual-DAS

Hard to reuse the existing DAS system Hard to reuse the existing DAS system

Higher coverage and capacity

Higher coverage and capacity requirementsrequirements

Passive components can’t meet the

Passive components can’t meet the large rangelarge range frequency band requirements

frequency band requirements Where to building LTE I

Where to building LTE I n-building network?n-building network?

MIMO or SISO ? MIMO or SISO ?

What is the strategy of

LTE in-building

network?

Which solution to select

for a new-build

for a new-build LLTE in-TE

in-building network?

building network?

How to maximum reuse

the existing 2G/3G DAS?

How to meet the

How to meet the coveragecoverage

and capacity requirements

and control interference?

Interference among different systems(GUL) Interference among different systems(GUL)

Unbalance power strength of two way DAS Unbalance power strength of two way DAS

Hard to predict the coverage result Hard to predict the coverage result

Hard to Deploy Hard to Deploy High Cost High Cost Bad Network Bad Network Performance Performance

Challenges of LTE In-building Network

(3)

Band

 Support various bandwidth: 1.4MHz, 3MHz, 5MHz, 10MHz, 15MHz, 20MHz

E-UTRA Band Uplink (UL) Downlink (DL) Duplex Mode FUL_low – FUL_high FDL_low – FDL_high

1 1920 MHz – 1980 MHz 2110 MHz – 2170 MHz FDD 2 1850 MHz – 1910 MHz 1930 MHz – 1990 MHz FDD 3 1710 MHz – 1785 MHz 1805 MHz – 1880 MHz FDD 4 1710 MHz – 1755 MHz 2110 MHz – 2155 MHz FDD 5 824 MHz – 849 MHz 869 MHz – 894MHz FDD 6 830 MHz – 840 MHz 875 MHz – 885 MHz FDD 7 2500 MHz – 2570 MHz 2620 MHz – 2690 MHz FDD 8 880 MHz – 915 MHz 925 MHz – 960 MHz FDD 9 1749.9 MHz – 1784.9 MHz 1844.9 MHz – 1879.9 MHz FDD 10 1710 MHz – 1770 MHz 2110 MHz – 2170 MHz FDD 11 1427.9 MHz – 1452.9 MHz 1475.9 MHz – 1500.9 MHz FDD 12 698 MHz – 716 MHz 728 MHz – 746 MHz FDD 13 777 MHz – 787 MHz 746 MHz – 756 MHz FDD 14 788 MHz – 798 MHz 758 MHz – 768 MHz FDD … … … … 17 704 MHz – 716 MHz 734 MHz – 746 MHz FDD ... … … …

(4)

Output Power

0  l 0 R 0 R 0 R 0 R 6  l l 0 0 R 0 R 0 R 0 R 6  l Resource element (k,l )

Not used for transmission on this antenna port

Reference symbols on this antenna port

0  l 0 R 0 R 0 R 0 R 6  l l 0 0 R 0 R 0 R 0 R 6  l l 0 1 R 1 R 1 R 1 R 6  l l 0 1 R 1 R 1 R 1 R 6  l 1RB = 12 Sub-Carriers

Bandwidth 1.4

3

5

10

15

20 RB

6

15

25

50

75

100 RE

72

180

300

600

900 1200



Output Power is RS Power



RS Power = RRU output – 10log(RE)-PA



For GT 10log(RE)=27.8dB



SISO: PA = 0

(5)

LTE Indoor Coverage Criteria Suggestion

RSRP

≥-95dBm@95%

SINR

≥15dB@95%

Spillage



10m far away from the building



First outdoor cell RSRP - Indoor cell RSRP > 10dB



Pathloss constrained by UMTS MCL



UMTS Pathloss A2E: 5 - (-80) = 85dB



Suggested LTE ERIP: -95 + 85 + 20log(21/18) ≈ -10dBm

(6)

Handover

A3

START: Mn + Ofn + Ocn - Hys > Ms + Ofs + Ocs + Off

STOP: Mn + Ofn + Ocn + Hys < Ms + Ofs + Ocs + Off

DEFAULT VALUE:

Ofn = Ofs

Ocn = Ocs

IntraFreqHoA3Hyst: 1dB

IntraFreqHoA3Offset: 1dB

Handover condition: Mn - Ms = Off + Hys = 2dB

IntraFreqHoA3TimeToTrig = 320ms

Overlap area = 1m/s * 0.32s = 32 cm

Suggested overlap area 1m~2m



Throughput = TBS * RB * 1000



SINR -> CQI -> MCS -> MO -> TBS ->

Throughput



Different Cell share same frequency

MCS

Modulation Order

0~9

QPSK

10~16

16QAM

17~28

64QAM

29~31

Reserved

(7)

SISO or MIMO

     

Split

Separated Areas: Open Areas: Easy to split

Large quantity of antennas

ard for civil work

Hard to split

Few antennas

Easy for civil work

Easy to Split Cell2 Cell Cel

Hard to

(8)

Pros:

Lowest additional workload Time to market , easy to deploy, Fully utilized existing DAS

Cons:

Could not reflect the LTE MIMO high performance

Hard to upgrade

Applicable Scenarios

:

TCO is most important

Existing DAS meet the requirements of the LTE system Splitter Coupler Antenna M u_l t _i - s y s t e_m C o_m b i n e_r GSM UMTS

LTE _{Replace existing}

combiner to

introduce LTE signal

(9)

Pros:

Fully reflect the LTE MIMO high performance

Time to market

Partially utilized existing DAS

Cons:

Need additional workload in existing High CAPEX

Applicable Scenarios

:

Capacity is most important

Existing DAS meet the requirements of the LTE system Splitter Coupler Antenna group II M u_l t _i - s y s t e_m C o_m b i n e_r GSM UMTS Antenna group I Splitter C o u p l e_r LTE

(10)

Pros:

Low power output for each path Low PIM

Cons:

Need additional combiners

Applicable Scenarios

:

Capacity is most important

Existing DAS meet the requirements of the LTE system Splitter Coupler Antenna group II GSM Antenna group I Splitter C o u p l e_r LTE

LTE DAS Choice 3: MIMO

(11)

Splitter

Antenna

Pros:

Reflect the LTE MIMO high performance Time to market

Partially utilized existing DAS

Cons:

Need additional workload in existing Partially sacrifice the performance of the LTE MIMO high performance

Applicable Scenarios

:

Coverage and Capacity is equally important

Existing DAS meet the requirements of the LTE system Splitter Coupler Antenna M u_l t _i - s y s t e_m C o_m b _i n e_r GSM UMTS LTE Macro LTE Micro

(12)

Isolation Requirement -- UMTS and LTE

Isolation for spurious emission:

P_spu = 10 log{ 10 exp (noisefloor+sendeg/10) – 10exp (noisefloor/10) } Where:

P_spu is the acceptable receiving spurious power of the victim system Noisefloor is the noise floor power of the victim system, unit in dBm

Sendeg is the allowable sensitivity degrade level of the victim system, unit in dB and taken as 1dB here When UMTS is the aggressor system and LTE is the victim system:

The P_spu = 10 log { 10 exp (noisefloor+sendeg/10) – 10exp (noisefloor/10) } = -123.78 dBm/RB

Since the spurious level of UMTS2100 is : -93dBm/RB, the minimum isolation for spurious emission is 30.8dB.

Reversely, when LTE is the aggressor system and UMTS is the victim system, we can calculate the minimum isolation for spurious emission is 30.6 dB.

Isolation for barrage jamming:

For 1dB sensitivity degrade, the UMTS2100 system should not receive a power higher than 5dBm at LTE1800 frequency. Because LTE eNodeB output 46dBm, thus the minimum isolation is 41dB. Reversely when LTE is the victim system, the isolation is 38dB.

Conclusion:

Taking UMTS2100 and LTE1800 as Example

Isolation Requirement

Spuriou s

Barrage jamming

LTE interferes UMTS 30.6 dB 41 dB UMTS interferes LTE 30.8 dB 38 dB

Minimum

isolation

for co-site

(13)

Target system Interference system Antenna and combiner isolation requirement LTE FDD 2600 GSM900 41dB GSM900 LTE FDD 2600 LTE FDD 2600 DCS1800 46dB DCS1800 LTE FDD 2600 LTE FDD 2600 UMTS2100 41dB UMTS2100 LTE FDD 2600 LTE FDD 1800 GSM900 41dB GSM900 LTE FDD 1800 LTE FDD 1800 UMTS2100 41dB UMTS2100 LTE FDD 1800

Isolation requirement -- G/U/L

(14)

Isolation requirement -- LTE Combiner and POI

(15)

RRU Tx power Cell Edge KPI Max DL Link Loss Space Loss difference b/w LTE 1800 & GSM 900 7/8” Cable loss per 100m difference b/w LTE 1800 & GSM 900

Total Power balance for direct co-site

GSM 900 40 dBm RxLev > - 80 dBm 120dB 6 dB 2 dB 0dB LTE1800 SISO 18.2 dBm RSRP > -95dBm 113.2dB +14.8 dB LTE1800 MIMO 21.2 dBm RSRP > - 95dBm 116.2dB _{+ 11.8 dB}

Note: The above Tx Power for GSM is the BCCH power, while the Tx Power for LTE is the RS Power.

Co-existing -- Can existing GSM DAS meet LTE Coverage KPIs

Conclusion:

For SISO/MIMO mode, the 40W LTE RRU can not be directly coupled into the existing DAS from the signal source to meet the same coverage with GSM 900.

(16)

RRU Tx power Cell Edge KPI Max DL Link Loss

Space Loss difference b/w LTE 1800 & UMTS

1800

7/8” Cable loss per 100m difference b/w

LTE 1800 & UMTS 1800

GSM 1800 40 dBm RxLev > - 80 dBm 120dB 0dB 0 dB 0dB LTE1800 SISO 18.2 dBm RSRP > -95dBm 113.2dB +6.8dB LTE1800 MIMO 21.2 dBm RSRP > - 95dBm 116.2dB _+3.8dB

Note: The above Tx Power for GSM is the BCCH power, while the Tx Power for LTE is the RS Power.

Co-existing -- Can existing GSM DAS meet LTE Coverage KPIs

Conclusion:

(17)

RRU Tx power Cell Edge KPI Max DL Link Loss

Space Loss difference b/w LTE 1800 & UMTS

2100

7/8” Cable loss per 100m difference b/w

LTE 1800 & UMTS 2100

UMTS 2100 33 dBm RSCP > - 78 dBm 111dB -1.3 dB -0.4 dB 0dB LTE1800 SISO 18.2 dBm RSRP > -95dBm 113.2dB -3.9 dB LTE1800 MIMO 21.2 dBm RSRP > - 95dBm 116.2dB _{- 6.9 dB}

Note: The above Tx Power for UMTS is the CPICH power, while the Tx Power for LTE is the RS Power.

Co-existing -- Can existing UMTS DAS meet LTE Coverage KPIs

Conclusion:

(18)

36.13Mbps 36.12Mbps 14.88Mbps -80dBm -95dBm -105dBm 4m 8m 12m

MIMO ≠ Multiple Antennas

Key Factors for LTE MIMO

                             2 1 2 1 22 21 12 11 2 1 n n s s h h h h r r N HS R  Array Gain  Diversity Gain

 Space Division Multiplex

Gain

 Interference Rejection

Combining Gain



Restrictions

•

Antenna port – Antenna number and RS pattern

•

Codeword – Transport Block that Transmitter supports

•

Layer – Dimension of wireless environment

•

Rank – Channel correlation

•

Block Coding – Block coding scheme, e.g. SFBC, FSTD

•

Algorithm – Schedule , pre-coding and combination that depend on Transmitter and Receiver realization

and configuration

•

Transport Mode – TM1-TM9 makes different throughput

•

Transmission Scheme – TxD

(Low channel quality; moving UE )

, OL-SM

(Low channel quality; moving UE )

, CL-SM

(Good/Low channel quality; static UE)

70.65Mbps 70.59Mbps -80dBm -95dBm -105dBm 4m 8m 12m 18.90Mbps

(19)

MIMO System

Two Single-polarized Antennas Network Mode

One Dual-polarized Antenna Network Mode

BBU RRU Distributed System Dual-polarized antenna Fiber Coaxial Cable BBU RRU Distributed System Fiber Coaxial Cable Single-polarized antenna

(20)

0 5 10 15 20 25 1 2 3 DL Throughput 0 5 10 15 20 25 1 2 3 DL Throughput

Open area suggest

Single-polarized

antenna

Cut off area

suggest

dual-polarized antenna

Dual-polarized antenna and Single-polarized antenna

Open area Cut off area

(21)

Space between MIMO paired antenna

Open area

0 5 10 15 20 25 1 2 3 2λ 4λ 6λ 8λ 10λ 12λ 0 5 10 15 20 25 1 2 3 2λ 4λ 6λ 8λ 10λ 12λ

Cut off area

λ = C/F = 3e8 / 18e8 = 0.167m

Space = 10

= 1 7m

(22)

MIMO Power Imbalance

Power imbalance should be controlled within 3dB for paired antennas.

(23)



Rich Experience



Seamless Solutions



Deep Understanding



End to End Capability

Existing & potential problem for indoor system will cut down the subscribers’ experience after on air,

better discover and handle them under construction

19% 8% 18% 22% 18% 15%

LTE Retrofit Problem Statics

Power imbalance No dual stream Combination problem Weak coverage Interference Hardware warning

Problem Analysis Level

Power imbalance Components and cables in different position makes different pathloss - Low

throughput and heavy fluctuation High No dual stream Antennas with no/weak signal - MIMO system with only SISO throughput Middle Combination problem Intermodulation/Wrong connection between LTE RRU and DAS in design or

implementation_– Wrong cell planning and interference Middle Weak coverage

Different ERIP requirement and path loss from GSM/UMTS for LTE, and improper RRU power - Low/Over-high RSRP, Call drop, Handover failure, Low throughput, Interference etc.

High Interference Same frequency for all neighbor cells with no code division - low SI NR, Call

drop, Low throughput, etc. High

Hardware warning VSWR Middle

0 20000 40000 60000 80000 100000 120000 140000 160000 1 2 3 Δ＝0 dB Δ＝3 dB Δ＝5 dB Δ＝10 dB

Differences in design between LTE and G/U

0 20000 40000 60000 80000 100000 120000 140000 160000 1 2 3 DL 15cm DL 50cm DL 110cm

(24)

HUAWEI IBS Solutions for LTE

Easy for deployment:

 installing dual DAS system at one

time, reduce workload

No unbalance issue of 2 way MIMO,

improve the MIMO performance

Use dual-polarized antennas, less

number, easy to deploy

Features

2 core feeder

Dual-polarized antenna

(25)

HUAWEI IBS Solutions for LTE

DRH DRH DRH DRH GSM BTS UMTS NodeB Main DCU LTE eNodeB Operator A GSM BTS

Slave DCU1 UMTS NodeB LTE eNodeB Operator B GSM BTS Slave DCU2 UMTS NodeB LTE eNodeB Operator C

Stadium Airport Subway/Tunnel Skyscraper

• Full band, multi-operator, multi-system sharing

• No need of dedicated equipment room profit from DCU cascading feature

• Easy for LTE evolution and frequency expansion with modularized structure

• Unified network management system, operation together with BTS

• 3D traffic map based on DRH-level MR • Remote interference and inter-modulation

detection, no need of onsite test

• Diff-operator or diff-system precise expansion on-demand, no need of onsite hardware adjustment

• 33% less power consumption with wideband DPD

technology

SingleDAS – Multi-Operator & Multi-System solution

(26)

HUAWEI IBS Solutions for LTE

PoE

 8 pRRUs per RHuB

Fiber

Cat5/6

100-150m

 4 cascaded RHuB per link

 392 pRRU per BBU

RF Module design

 flexible RFimbedded for G/U/L /Wifi

 100mW per RF module, maximum 3

 2T2R

Features

High capacity: 192 pRRU/BBU, each pRRU suppport 1 cell

Fast deployment: fiber and CAT5 instead of feeder

Antenna-level management: pRRU-level management

LTE new-build scenario with high capacity demand

Scenarios which can’t use feeder

Lampsite – No cable solution

Application scenarios

(27)

HUAWEI IBS Solutions for LTE

Small residential area Shopping street Villa

Outdoor site for in-building coverage

with macro & Atomcell combination solution Indoor micro scenario coverage w ith indoor AtomCell

Fast deployment High capacity Low cost, fast deployment

Macro Site

Small office Shops Coffee bar Restaurant

AtomCell - Micro scenario solution

AtomCell Ceiling Ethernet Pico Adapter PoE Ethernet Ethernet PoE C AC 1 Pico

(28)