Broadband Evolution and Spectrum Challenges

Dr Ayman Elnashar

Sr. Director - Wireless Broadband & Site Sharing

EITC (du) - UAE

Agenda Driving Wireless Broadband

Innovation in UAE: du Broadband Portfolio

Fixed Wireless Broadband Evolutions

Mobile Broadband Evolutions

DC-HSPA+

LTE Evolution

LTE Deployment Strategy

LTE Terminals

du Broadband Portfolio

du outdoor Mesh-WiFi

Co

ve

rag

e/M

ob

ilit

y

Data Speeds (Kbps)

Outdoor

Mesh

WiFi

802.16e

WiMAX

Lo

ca

l A

rea

Fix

ed

Wir

ele

ss

W

ide

Are

a

Mo

bile

Me

tro

Are

a

No

ma

dic

Fixed xDSL & Fiber

Ultra Broadband

3.X G 2G

Fixed Wireless

2.5G 3G

802.11b/a/g/n

Broadband

everywhere

FDD & TDD

TDD

du WiFi Hotspots

Fixed Wireless Broadband services using OFDM (PTP &

PTMP) high capacity Links with up to 300Mbps for SME and

Enterprise customers

du WiMAX network for the Dubai Metro**

du Fixed network Services

du UAE Nationwide Mobile Network

Nationwide Mobile Broadband HSPA+/DC-HSPA+ (42Mbps)*

3

* Du is the 1st in UAE to deploy the DC-HSPA+ nationwide and UAE is the 6th nation globally to deploy this technology thanks to du. **Winner of 2009 most innovative mobility project by Cisco Networkers

802.16d

WiMax in 3.5GHz for

small SME

LTE Evolution

Fixed Wireless Broadband

Services

4

Fixed Wireless Broadband Evolution using state of the art OFDM technology: New Features

Up to 300Mbps in 40MHz TDD channel using MIMO 2x2 with cross-polarization which means Spectral efficiency of 6+ bit/Hz/s.

Support of 4.9 6.0 GHz in one radio.

Dynamic TDD: Adjusts the uplink/ downlink ratio based on traffic demand.

Low Latency (

Point-to-Point with Double

Stream MIMO (near to the BTS)

6

Vertical

Polarization

Horizontal

Polarization Horizontal

Polarization

Backhaul

Different data is sent separately over two polarizations

resulting in higher radio efficiency

Vertical

Polarization

Backhaul

DC-HSPA+ Evolution

7

HSPA+ Evolution

HSDPA

Single Carrier 5MHz Dual Carrier 10MHz

HSPA+ Improves Peak Rates while providing Higher QoS and Customer Loyalty

14.4M

21M

28M

42M

28M

42M

56M

84M

64QAM MIMO 64QAM+MIMO DC DC+64QAM DC+MIMO DC+MIMO+64QAM

8

DC-HSPA+: Improve Data Rates

Anchor Carrier

Frequency 1

Supplementary Carrier

Frequency 2

Dual cells covers the same

geographical area

Downlink peak rate

double 28.8M/42Mbps

5MHz 5MHz

frequencey1 frequencey2 f

Two frequencies are

adjacent

Use 2 adjacent carriers to

transmit simultaneously data to

the same user

Full use of the two cells resource by Joint Scheduling and Load Balance

9

HSPA+ Evolutions: MIMO vs. DC

Criteria/Evolution DC MIMO

Peak Rate 42Mbps in 10Mhz band 42Mbps in 5Mz band

Coverage Performance Better --

Throughput Performance -- Slightly Better

Latency Performance Better --

Service Type (Full Buffer) -- Better

Service Type (Burst) Better --

CAPEX Investment Low High

DC introduces high improvement at the user level;

while MIMO introduces little improve at the cell level;

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11

Cell Radius

Dense Urban Urban Suburb Rural

MIMO+64QAM 0.33 0.5 1.7 3.9

DC+64QAM 0.43 0.63 2.2 5.3

Remark: Cell edge throughput 1024kbps

Coverage Comparison

0.33 0.5

1.7

3.9

0.43 0.63

2.2

5.3

0

1

2

3

4

5

6

Dense Urban Urban Suburb Rural

Scenario

Cell

Radiu

s(k

m)

MIMO+64QAM

DC+64QAM

HSPA+ Coverage Comparison

11

LTE Evolution

12

OFDM, the state-of-the-art Radio Access Technology: Moving from Voice to Broadband with VoIP

13

Why OFDM/SC-FDMA

The main advantage of OFDM, as is for SC-FDMA, is its robustness against multipath signal propagation, which makes it suitable for broadband systems compared to TDMA/CDMA techniques.

SC-FDMA brings additional benefit of low peak-to-average power ratio (PAPR) compared to OFDM making it suitable for uplink transmission by user-terminals to extend battery life.

OFDM can also be viewed as a multi-carrier system but each subcarrier is usually narrow enough that multipath channel response is flat over the individual subcarrier frequency range, i.e. frequency non-selective (i.e., flat fading) and hence receiver design is very simple.

In other words, OFDM symbol time is much larger than the typical channel dispersion. Hence OFDM is inherently susceptible to channel dispersion due to multipath propagation.

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15

Inter-site (UL)

ICIC in frequency domain: In the edge of the

site, the bandwidth is divided into 3 pieces,

and each site use a piece; In the center of

the site, the left bandwidth can be used;

Intra-site (UL)

ICIC in time domain: adjacent cells use

different subframe; as show in the Figure,

yellow zone use odd subframe, while light

blue zone use even subframe.

Inter/Intra-site (DL)

Cell edge: frequency division, separated by transmit power

Cell central: all bandwidth are transmitted. Control coverage to reduce interference

Site2

Uplink

Site1

Site3

Sector 1

Sector 2

Sector 3

Interference Management in LTE

Downlink

16

2x2 MIMO

eNodeB UE 1

1x2 SIMO

eNodeB UE 1

In typical urban area:

15%~28% gain over SIMO @ Macro

~50% gain over SIMO @ Micro

MIMO: the Key to Improve Cell Throughput

17

LTE RAN Performance: Simulations Results

Uplink

Downlink

Peak Cell/User Throughput Average Cell throughput

Average cell Throughput LTE FDD

20 MHz Downlink

33

39

57

0

10

20

30

40

50

60

70

MIMO 2x2 MIMO 4x2 MIMO 4x4

MBps/s

0

1

2

3

Sp

ec

tra

l eff

icie

nc

y in

Bp

s/s

/HzAverage cell throughput

Spectrum Efficiency

Ultra-Low Latency

300 ms

52 - 82 ms

13 ms

12-19 ms

Delay to access a 60kByte

web page (from Idle)

Connection Setup

Handover interruption

End-to-end RTT

Peak Throughput LTE FDD 20 MHz

5886

173

326

0

100

200

300

1X2 UL

16 QAM

1X2 UL

64 QAM

MIMO

2x2 DL

MIMO

4x4 DL

Mbps

17

18

Horizontal Distance: 0.5m

2/3G band x LTE band x

Vertical Distance: 0.2m

2/3G band x

LTE band x

Horizontal 0.5m or vertical 0.2m antennas separation is the minimum requirement

Antennas Separation and Guard Band

Requirement for Co-Existing System

Guard band Requirement for Co-existing Systems ( MHz )

Co-existing Systems System Standards LTE Bandwidth

LTE Other system 5MHz 10MHz 15MHz 20MHz

LTE1800 + GSM1800 protocol protocol 0.2 0.2 0.2 0.2

LTE2100 + UMTS2100 protocol protocol 0.33 0.08 0.17 0.42

LTE Band X + LTE Band Y protocol protocol 0 0 0 0

LTE FDD + LTE TDD protocol protocol 10 10 10 10

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HSPA+ vs. LTE

HSPA+ LTE

Peak Rate 84Mbps@10MHz 172Mbps@20Mhz (2x2)

326.4Mbps@20MHz(4x4)

Spectrum Efficiency

(Peak)

8.4bps/Hz (Peak for DC+ MIMO

+ 64QAM) 8.6bps/Hz (Peak for 2x2 MIMO)

Spectrum Efficiency

(Average cell

throughput) (DL/UL)

1.424/0.6 (MIMO+64QAM)

1.717/0.99 (2x2 MIMO)

20% improvement in DL

65% improvement in the UL

Transmission

bandwidth Full system bandwidth Variable up to full system bandwidth

Suitability for MIMO

(i.e., MIMO Gain)

Requires significant computing power due to signal being defined in the time domain and on top of spreading (frequency selective channel)

Ideal for MIMO due to signal representation in the frequency domain and possibility of narrowband allocation to follow real-time variations in the channel (Frequency nonselective channel) 20

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Coverage Comparison

Scenario Cell Radius in DL (Km)

Dense urban Urban Suburban Rural

HSPA 2.1GHz 0.38 0.57 2.34 4.62

LTE 2.1GHz 0.49 0.78 3.18 5.33

LTE 2.6GHz 0.4 0.64 2.58 4.68

DL Cell Radius Comparison. DL Cell edge throughput 512kbps, Indoor Coverage, 90% Cell Loading

0

1

2

3

4

5

6

Dense urban Urban Suburban Rural

0.380.57

2.34

4.62

0.490.78

3.18

5.33

0.40.64

2.58

4.68C

ell R

ad

ius

in

DL

(Km

)

Scenario

Coverage Comparison

HSPA 2.1GHz

LTE 2.1GHz

LTE 2.6GHz

HSPA Cell Radius as a Function of Loading

HSPA Cell Radius as a function of Loading

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

10 20 30 40 50 60 70 80 90 100

Cell Loading(%)

Ce

ll R

ad

ius(

km)

UL

DL

Cell

Loading(%)

Cell Radius (Km)

10 20 30 40 50 60 70 80 90 100 %

UL 0.8 0.77 0.74 0.71 0.67 0.63 0.59 0.52 0.43 0.02 98%

DL 0.79 0.75 0.71 0.67 0.62 0.58 0.54 0.49 0.45 0.43 45%

HSPA+ 2.1GHz,Urban scenario, indoor coverage, 128kbps/512kbps in UL/DL

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LTE Cell Radius as a function of Loading

LTE Cell Radius as a function of Loading

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

10 20 30 40 50 60 70 80 90 100

Cell Loading(%)

Ce

ll R

ad

ius(

km)

UL

DL

Cell

Loading(%)

Cell Radius (Km)

10 20 30 40 50 60 70 80 90 100 %

UL 0.52 0.51 0.5 0.49 0.48 0.47 0.46 0.45 0.44 0.42 19%

DL 0.79 0.77 0.76 0.74 0.72 0.71 0.68 0.66 0.64 0.61 23%

LTE 2.6GHz,Urban scenario, Indoor coverage, 128kbps/512Kbps in UL/DL.

Average Cell Throughput Comparison

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Scheme UL Average Cell

Throughput Remark

HSUPA 10ms 2.1Mbps CAT5,urban,UL cell load 75%

HSUPA 2ms 2.3Mpbs CAT6,urban,UL cell load 75%

HSUPA 16QAM 3.0Mbps CAT7,urban,UL cell load 90%

LTE 10MHz 9.7Mpbs Urban,2.6GHz

LTE 20MHz 19.8Mbps Urban,2.6GHz

Scheme DL Average Cell

Throughput Remark

HSPA(16QAM) 6.0Mpbs Urban, bandwidth 5MHz

HSPA+(64QAM) 6.41Mbps Urban,bandwidth 5MHz

HSPA+(MIMO) 6.98Mpbs Urban,bandwidth 5MHz

HSPA+(MIMO+64QAM) 7.12Mbps Urban,bandwidth 5MHz

HSPA+(DC+16QAM) 6.43Mpbs Urban,bandwidth 5MHz

HSPA+(DC+64QAM) 6.89Mbps Urban,bandwidth 5MHz

LTE 10MHz 16.92Mpbs Urban,2.6GHz

LTE 20MHz 34.34Mbps Urban,2.6GHz

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Supported Simultaneous users for HSPA+ and LTE

Assumptions:

- Urban Scenario (500 sites)

- HSPA+

1. Scenario 1: 1st carrier R99+HSAP(5 codes), 2nd carrier HSPA+(15 codes)

2. Scenario 2: 1st carrier HSPA+ (15 codes), 2nd carrier HSPA+(15 codes)

- LTE bandwidth: 10 & 20 MHz

- Traffic Model assumption: data user 50kbps, voice user 0.025Elr

- HSPA+ can support CS and PS service, LTE only support PS service.

Capacity/Cell

BB subscribers

supported per

site

Number of supported

simultaneous users

per network

LTE Capacity gain

compared to HSPA+ %

HSPA 2.1GHz

(scenario 1) 22Elr(CS AMR12.2)

9.3Mbps(PS HSPA+) 325 162K 100%

HSPA 2.1GHz

(scenario 2)

13 Mbps:2 native HSPA+

carriers, no voice with

DC-HSPA+

455 227K 140%

LTE 10MHz @

at 2.6 GHz 16.92 Mbps 592 296K 182%

LTE 20 @

2.6GHz 34.3Mbps 1202 601K 370%

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LTE Terminals

LTE Commercial Terminals

Thank You

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