Advanced Broadband Wireless Standards from ETSI and Co-operation with WiMAX

Advanced Broadband Wireless Standards from ETSIand Co-operation with WiMAX

Prof. Dr. Bernd Friedrichs- Marconi Communications, Germany - ETSI BRAN Chairman

WCA’s 11th Annual International Symposium & Business ExpoSan Jose, CA, Jan. 12-14, 2005

2Bernd Friedrichs, EG/FW-RSE

• ETSI BRAN structure

• Status of BRAN HiperAccess and HiperMAN

• Details of HiperAccess Technology

• Relations to standardization bodies and forums

• Co-operation ETSI - WiMAX Forum

• Conclusions

Overview


• ~700 member companies from 55 contries in 5 continents

• ~11,000 technical standards and deliverables since 1988

• ~60 co-operation agreements

• Market driven organizationmembers decide about work program and resource allocation

• Established in 1988, as non-profit making organization,

based in Sophia Antipolis, Nice Cote d‘Azur (France)

• www.etsi.org

ETSI European Telecommunications Standards Institute


Decision Making

• Members shall endeavour to reach consensus on all issues.

• If lack of consensus: voting can be performed using individual member company weights (1...45 depending on company revenues, one vote per company, approval requires 71%)

Open Standardization Process

• Each ETSI member can actively or passively participate (incl. voting).

• All documents and standards are always freely accessible.

IPR Policy

• Each ETSI member has the obligation to inform about Essential IPRs it becomes aware of.

• IPR owners shall grant irrevocable licenses on FRAND (fair, reasonable and non-discriminatory) terms and conditions.

ETSI Working Methods


Global Wireless Standards

IEEE 802.15 Bluetooth

WAN

MAN

LAN

PAN

IEEE 802.11WirelessLAN

HiperLAN/2RLAN

IEEE 802.16 WirelessMAN

HiperMAN & HiperAccess

UMTS, EDGE (GSM)

ETSIBRAN

IEEE 802 ETSI

WiFi*

*) Industry fora for promotion and certfication

WiMAX*


BRAN Structure

PHY

DLC

CL

Testing

ETSI BRAN(Broadband Radio Access Networks)

Chairman: Bernd Friedrichs (Marconi)

HiperLan/2(High Performance LAN)

Wireless LANat 5 GHz, connection-based,

OFDM, 54 Mbps, QoS

HiperAccess(High Performance Access)

Fixed broadband wirelessPMP system above 11 GHz,

single carrier, 120 Mbps

HiperMan(High Performance MAN)

Fixed broadband wirelessPMP system below 11 GHz,

OFDM, IP-optimized

Spectrum regulatory issues, Harmonized Standards

PHY

DLC

CL

etc.

PHY

DLC

Profiles

MIB

Regulatory Competence GroupTesting


Transition to TC (Technical Commitee) in 2004

ToR (Terms of Reference) BRAN is responsible for all broadband radio (access) systems Several vertical groups for technology-dependent activities Regulatory competence concentrated in horizontal RCWG

- to develop Harmonised Standards covering essential requirements under article 3.2 of the R&TTE directive, - to assist regulatory bodies to define spectrum requirements and radio conformance specifications for new broadband radio networks

Extensions under discussion Non-interoperable systems (i.e. proprietary, coexistence specs) Transport systems (e.g. classical Point-to-Point hops) Higher layers including network aspects

(e.g. IRAP = International Roaming Access Protocols (WiFi)) Other

(e.g. WIGWAM = Wireless Gigabit (RLAN) with Advanced Multimedia Support) Merger with ETSI TM4

BRAN Status


ETSI Experience GSM, DECT, 3G, Tetra, etc. The working methods and approaches have given very good

results in terms of interoperability 3G considers the test specs „very good value for money“

Base standards (for air interface) PHY and DLC layers independet of core network Convergence sublayers for packet- and cell-based core networks

Base standards (for network) The successful deployment of large-scale portable or mobile

networks requires also the development of interfaces and protocols above the scope of the air interface

Work already started on MIB and management

BRAN Characteristics (1 of 5)General


Test specifications Normative part of standard Controlled in the open forum in the same way as the base specs Actual testing and certification is left to industry and their

associations

Test methods Good results from using advanced spec methods and languages For the first time, virtual protocol testing (UDP/IP based, via API)

was used, showing the capability to detect and resolve potential problems in implementations before the HW becomes available

BRAN Characteristics (2 of 5)Testing


Testing organization Work is progressed through STF (Special Task Force) STF funded by ETSI, operating under the guidance of BRAN Supported by PTCC (Protocol and Testing Competence Center)

BRAN STF All BRAN conformance test specifications were produced in STFs More than 70 documents were published in the last two years About $ 2,000,000 funding was spent for BRAN STFs About $ 520,000 total cost were spent for HiperMAN / WiMAX

BRAN Characteristics (3 of 5)STFs


Interoperability testing = Two implementations trying to interwork Can test only normal behaviour Can test exceptional behaviour only by chance

Golden unit testing = An implementation that is somehow representing a standard trying to interwork with an implementation under test

Conformance testing = A test tool evaluating an implementation under test Can test both normal and exceptional behaviour Can repeat the specific test any time and any number of times (following

corrections for example)

ETSI has achieved good results using a combination of conformance testing followed by some level of interoperability testing

BRAN Characteristics (4 of 5)Testing - Comparison of Approaches


Basic protocol standard development• Abstract Syntax Notation (ASN.1) message structure specification, ITU-T X.680• Packed encoding rules (PER) for transfer encoding, ITU-T X.691 • Message Sequence Charts (MSC) for message flow description, ITU-T Z.120, • Specification and Description Language (SDL) specification, ITU-T Z.100

- SDL models used to precisely define the protocol behaviour. - Simulations and validations to early remove ambiguities and erroneous protocol behaviour.

Protocol test specifications (ITU-T X.291...296, ISO/IEC 9646)• PICS Protocol Implementation Conformance Statement• TSS & TP Test Suite Structure and Test Purposes• ATS Abstract Test Suite (TTCN)

- Significant effort was spent (30 man month of funded expert work plus voluntary contribution by member companies and ETSI PTCC work)

Radio test specifications• RCT Radio Conformance Test• EN Harmonized Standard (European Norm), covering the essential

requirements of article 3.2 of the EC R&TTE Directives

BRAN Characteristics (5 of 5)Standards for Base and Test Specifications


BRAN HiperAccess (1 of 4) Overview

Main applications Cellular backhauling SOHO, SME Typically too expensive for residential access / WLL / LMDS

ETSI BRAN developed protocol stack and radio specifications

Optimized for ATM and Ethernet

Strong points Suitable for immediate deployment in GSM and UMTS networks Technical quality

– Precision of specification– Well controlled optional features – Absence of ambiguities– Test specifications with ETSI strength (MBS2)

High spectral efficieny, high QoS, high reliability


BRAN HiperAccess (2 of 4) Set of Specifications

in total ~2000 pages


Focus on frequency bands • 40.5 - 43.5 GHz• 31.8 - 33.4 GHz• 27.5 - 29.5 GHz• 24.5 - 26.5 GHz• other lower frequencies

Channel size = 28 MHz, Baudrate = 22.4 MBaud• Paired bands (FDD mode, fixed asymmetric rates)• Unpaired bands (TDD mode, adaptive asymmetric rates) • Optimum trade-off between costs, peak data rate and statistical multiplex

gain

Important parameters

BRAN HiperAccess (3 of 4)Basic Features PHY Layer


BRAN HiperAccess (4 of 4) Achievements and Plans

High stability of base and test specifications achieved Only minor corrections expected in 2005 Further harmonization with IEEE 802.16-WirelessMAN-SC

Commercial roll-out First BRAN-compliant product was rolled-out in December 2004

(Point-to-Point derivative of HA) Full HiperAccess-compliant products will be available in 2005 High interest from numerous operators


AT 1

AP

AT n

AT 2

TDMA uplink

...

54321 t

1

23

4

5

AT 1

AP

AT n

AT 2MACPDU

MACPDU

MAC PDU

...

TDM downlink

...

MACPDU

Time Division Multiplex (TDM) in Downlink, Time Division Multiplex Access (TDMA) in Uplink

Further important properties of downlink and uplink


Transceiver Chain

ARQTX buffer

MACPDU

RScodeword

FECblock

Burst

Symbolstream

(cont.in DL, bursty in UL)

Preambles with QPSK

One preamble for one or

several FEC blocks

Including trellis termination

for each RS CW,only present for

some PHY modes

Up to four MAC PDUsper RS CW

Only payload of unicast

MAC data PDUsis encrypted

Operation on groups

of MAC PDUs corresponding to RS CWs,

UL only

from

dat

a in

terfa

ceto

dat

a in

terfa

ce

RS error detection flag for ARQ

Request for ARQ re-transmission

Encryption Scrambling OuterRS Encoder

InnerConvol.Encoder

Insert Preamble

Modulation

Radio link (physical channel)

Operation oncomplete frame

except preamble(s),

initiated per frame

ARQRX buffer Decryption Descrambler Outer

RS Decoder

InnerConvol.Decoder

Remove Preamble,Equalizer

De-Modulation

MACPDU

MACPDU

MACPDU

Burst


PHY Modes (1 of 9)Definition, Robustness vs. Efficiency

RS-encoder

Convol.encoder

Modulator(2M-ary)

Pulseshaping

ymbol)codebits/s (

rate symbol

M

rs

)25.0(

bandwidth)1(

srB

errors) ecorrectabl 8PDU oflength 5554

rd,PDU/codewo 4...1(

2

t...n

l

tnl

nlRouter ]1,2/1[innerR

PHY mode defined by - concatenated coding and - modulation(where „PHY“ refers to the physical layer of OSI model)

1bandwidth

rate datainfobit efficiency Spectral

MRR

B

MRRr innerouterinnerouters

Infobits Codebits Symbols Waveforms


Frame Structure Overview

Control zone

(PHY mode # 0)

PHY mode #1

region

PHY mode #2

region

PHY mode #3

regionPHY mode #4

region

Framepadding

FramePreamble TDM zone

Downlinkframe

Invitedranging bursts

Bandwidthrequest

contentionwindow

GrantedUL burst

GrantedUL burst

GrantedUL burst

GrantedUL burst

Downlinkmap

Uplinkmap

ARQmap

BroadcastFrame

Info

to frame # (N-2)

Uplinkframe

frame offset

Order of ranging burst and contention window is just an example

Control zoneenlarged


PHY Modes (3 of 9)DL Frame with Concatenated Coding

Control zone TDM zone

1 ms (fixed duration)

variable length

PHY mode 1region

PHY mode 2region

PHY mode 4 (last)region

variable length variable length variable length

FramePadding

Modulated & encoded (RS+CC) sequenceincluding trellis termination bits per each RS codeword &

padding bits to complete a symbol per each FEC block

Preamble(32 symbols)

RS codeword RS codeword RS codewordLast

RS codeword

fixed length fixed length fixed length variable length

MACPDU 1

MACPDU 2

MACPDU 3

MACPDU 4

MACPDU 1

MACPDU 2

MACPDU N

where N=1,2,3,4

Remarks:• ATM cells and DLC messages

are aligned to PDUs, IP packets

are segmented to PDUs• PDUs are aligned to RS blocks• Block structure preserved by

terminated convolutional coding• Code blocks are aligned to

symbols and regions (DL) and bursts (UL)

• Advantages: error detection and ARQ


PHY Modes (4 of 9)Maximum Range per Mode

tyavailabiliRXTX

rainfree

requiredTx p

GG

LLNL

N

I

IN

CPP

01

Maximum d, PTx and pavailability are related as

>1I is time-variant

mainly dependent on

Lrain is time-variant

rate fallrain ,,,, tyavailabilic pBfd

Stand-alone cells (without interference from adjacent cells, without DL ATPC)

Rain fading

Mode 4Mode 3Mode 2Mode 1

Link loss

Cell radius

Clearsky


Adaptive Operation

Adaptation according to• d = distance (fixed)• I = interference (slow in DL, fast in UL)• N = noise (representing link budget C/N)• Lrain = rain fading (fast, 20 dB/s)Mechanisms• PHY mode change per terminal• PHY mode change per frame• combined with ATPC (Adaptive Transmit Power Control)Control loop• decided centrally by AP• based on

• measurement reports from AT • received signal in AP

• commanded as• announcement in DL map for DL, • granted per UL map for UL


Lrain=Rain fading

26 GHz32 GHz42 GHz

26 GHz

32 GHz

42 GHz

Radio Link Model (6 of 8)

Free-Space Pathloss and Rain Fading

Lfree =Pathloss


PHY Modes (5 of 9)Throughput, Range vs. Availability @ 28 GHz

99.99 %99.999 %99.9 %

99 %

Clear sky

6.5 km @ 99.9%


DL worst sector(C/I)min = 20*log(5) = 14.0 dB

UL worst sector

Interference degradation typically depends on direction• a sector may have poor properties for DL but good properties for UL• interference is time-invariant for DL and time-variant for UL

Interference in Downlink and Uplink


C/(N+I) Pattern for 5x5 Rectangular Constellation (Downlink, ClearSky, ReUseFactor=4)

2 4 6 8 10 12 14 16 18

2

4

6

8

10

12

14

16

18

Distance [km]

Dis

tanc

e [k

m]

C/(N+I) pattern @ BS distance = 4 km; TX power = 21.5 dBm; rainfading = 0 dB/km

10

12

14

16

18

20

22

24

26

28

worst sector enlarged


C/(N+I)~C/N Pattern for 5x5 Rectangular Constellation

(Downlink, RainFading, ReUseFactor=4)


CDFs for 5x5 Rectangular Constellation (Downlink, ClearSky, ReUseFactor=4)


Marconi’s Radio Network Planning Tool(Realistic Constellation with 142 Sectors)

Input: Base station sitesCoverageTraffic load

Output: SectorizationCarrier frequencies (2)Polarization (coloured)

Interference critical zone = 1.4% of coverage (blue)


Detailed Layer Structure

Initiali-zationcontrol

Securitycontrol

Radiolink

control

Connec-tion

control

Traffic data connections

ASN1 coding

SAR sublayer

MAC sublayer

ARQ sublayer (UL)

51byte DLC SDU(fixed length)

Radio channel (above 11 GHz)

DLC

PHY

ATM cells(53byte)

IP packets (variable length)

CL

54...55 byte PDU

MAC management connections

Encryption

Scrambling

Reed-Solomon Encoding

Convolutional Encoding

Modulation

Cell-based CL Packet-based CL

Decryption

Descrambling

Reed-Solomon Decoding

Convolutional Decoding

Demodulation


Realization of high Multiplex Gain requiresefficient and fast Bandwidth Allocation Schemes

...

Requests per connection aggregate (various mechanisms)

AP

Uplinkscheduler

(for carrier)

Downlinkscheduler

(for carrier)

Grants per terminal via UL map

Uplink allocation(distributed, mainly in AP)

Uplinkscheduler

(use of grants)

AT n

via DL map (no action from AT)

Downlink allocation(central in AP)

Uplinkscheduler

(use of grants)

AT 1

CAC

Frequency planning (Blocking of PHY modes)

CAC = connection admission control


Example of ASN.1 Base Specification

PhyModeSetDescriptor ::= SEQUENCE { psdi Psdi, -- 4 bit downlinkPhyThresholdsList PhyThresholdsList, -- variable uplinkPowerModChangeListNonTc UplinkPowerModChangeList, -- variable uplinkPowerModChangeListTc UplinkPowerModChangeList -- variable}

Psdi ::= INTEGER {phyModeSet1 (1), phyModeSet2 (2)} (0..15) -- 4 bit

PhyThresholdsList ::= SEQUENCE (SIZE(2..7)) OF PhyThresholdPair

UplinkPowerModChangeList ::= SEQUENCE (SIZE(1..6)) OF UplinkPowerModChangePair

PhyThresholdPair ::= SEQUENCE { upThreshold CnrThreshold, -- channel quality increase downThreshold CnrThreshold -- channel quality decrease}

UplinkPowerModChangePair ::= SEQUENCE { upPowerModChange UplinkPowerModChange, -- channel quality increase downPowerModChange UplinkPowerModChange -- channel quality decrease}

CnrThreshold ::= INTEGER(0..255) -- 8 bit,granu=0.25dB,range=[4,40]dB,absolute

UplinkPowerModChange ::= INTEGER(0..32) -- 6 bit,granu=0.5dB, range=[ -8, +8]dB


BRAN HiperMAN (1 of 2)Overview

Main applications First release: FWA below 11 GHz Residential (self installation), SOHO, SME (wireless DSL) Mesh radio networks (radio based routers)

Features (100% selected by WiMAX Forum) Optimized for IP traffic, full QoS support Both FDD and TDD, including H-FDD CPE High spectral efficiency and data rates, up to 25 Mbit/s in 7 MHz Adaptive modulation (from QPSK to 64-QAM) Interoperability profiles for 1.75 MHz, 3.5 MHz and 7 MHz Uplink OFDMA (high cell radius possible, up to 50 km in PMP with

directive antenna) Hooks for advanced antenna systems High security TEK encryption algorithms


BRAN HiperMAN (2 of 2)Technical Specifications

Standards (published in 2004) ETSI TS 102 177 PHY layer ETSI TS 102 178 DLC layer ETSI TS 102 210 System profiles

Functional Requirements ETSI TR 101 856

System Reference Documents ETSI TR 102 079 for the band 5.725 GHz to 5.875 GHz

Drafting activity MIBs for Network Management Test standards (PICS, TSS&TP finished in 2004, ATS) Support for nomadic systems etc.


BRAN RCWGRegulatory Competence Working Group

5 GHz Harmonized EN (RLAN) To be used for European type approval in < 5.725 GHz ETSI EN 301 893 v1.2.3 - 5 GHz high performance RLAN;

Harmonized EN covering essential requirements of article 3.2 of the R&TTE Directive

5.8 GHz Harmonized EN (FWA) To be used for European type approval in 5.725 - 5.975 GHz

System Reference Document (HiperMAN) Fixed - nomadic convergence of BWA systems To be used by ECC for more spectrum allocation


BRAN Relationship with Other Bodies and Forums

ETSI OCG

ETSI TM4

ETSI ERM


Relation BRAN - ITU

Draft ITU-R Recommendation on Radio Interface Specifications(Requirements and Standards)

BRAN and IEEE 802.16 provide harmonized inputs

ITU-D Report on Broadband Technologies (ITU-D Q20/2) BRAN provided input

ITU-APT Seminar on BWA (Busan, Korea, Sept. 2004) Presentations from BRAN Vice-Chair


Relation BRAN - IEEE802.x (1 of 4)Overview

currentlyno activities

802.21Roaming

mobile extension for HM tbd.

802.20MBWA

currently no activities

802.15WPAN

formal co-operation agreement expected soonWiMAX Forum

Base spec: HM harmonized with IEEETest spec: Norm. ref. in IEEE to HM PICS and TSS&TP

HiperMAN(fixed or nomadic

operation)

802.16(<11 GHz)

(16e mobile extension)

same PHY layer(except one FEC detail),

further harmonization intended

(TC layer, protocol stack)

HiperAccess802.16 (10-66 GHz)

WMANpromotion:

same PHY layerHiperLAN2H2GF

802.11aWiFi

WLANpromotion:

RemarkETSI BRANIEEE 802


Relation BRAN - IEEE802.16 (2 of 4)Mutual Influence HiperMAN - IEEE sub11GHz

Source: Mariana Goldhamer, ITU-APT Seminar on BWA, Busan, Korea, Sept. 2004


Relation BRAN - IEEE802.16 (3 of 4)Coding Scheme

ETSI BRANHiperAccess

ETSI BRANHiperMAN

IEEE 802.16WirelessMAN-SC

IEEE 802.16WirelessMAN-OFDM

Same FEC scheme

Why different FEC schemes?


Relation BRAN - IEEE802.16 (4 of 4)MAC Layer

ETSI BRANHiperAccess

ETSI BRANHiperMAN

IEEE 802.16WirelessMAN-SC

IEEE 802.16WirelessMAN-OFDM

Same generic MAC layer

MAC optimizedfor backhauling


ETSI and WiMAX Forum have a common interest to perform and promote standardization with the aim of a global

information infrastructure in avoiding duplication of technical work

ETSI and WiMAX Forum co-operate for testing and certification to develop conformance test specifications to validate the test suite

Status of Agreement Details of agreement almost agreed (some legal issues to be fixed) Signature expected soon Technical experts are already working on this basis since mid 2004

Co-operation ETSI - WiMAX (1 of 3)The Agreement


WiMAX Forum set up the certification scheme to assure interoperability of devices control all aspects of certification

ETSI is harmonizing and developing HiperMAN test specifications

(PICS, TSS&TP, ATS) that could be used for certification offers unique resouces

– TC MTS (Methods for Testing and Specification)

– ETSI PTCC (Protocol and Testing Competence Center)

– ETSI Plugtest Service has proven expertise in testing matters and

has proven track record of working with industry fora like WiMAX

Conformance and interoperability testing Both complement each other For best probability of interoperability between products - do both!

Co-operation ETSI - WiMAX (2 of 3)Details


Co-operation ETSI - WiMAX (3 of 3)Conformance Testing Process (ISO 9646 Scheme)

Test Suite (Test Cases)

ATS

Req. checklist

PICS

Test Purposes

TSS & TP

testingTest

Report

logging and

analysis

Test System

Base Standard

(or Profile)

implementation

Product

Implementation Under Test

compilation

Executable Test Suite

(e.g., C++)

Industry

validation

Continuous interaction between all partners is essential for the process (WiMAX, BRAN, PTCC, STF, test house, test tool vendors, manufacturers)


Conclusions

Wireless industry needs global standards

ETSI BRAN supports all harmonization efforts with other parallel standardization bodies

Co-operation BRAN - IEEE 802.16 shows what can be achieved how standard bodies can contribute to each other

Co-operation BRAN - WiMAX Forum Important signal to the market ETSI benefits from WiMAX marketing and certification

strength WiMAX Forum benefits from ETSI experience and work

approach

ETSI has access to regulatory bodies


• http://portal.etsi.org/bran(ETSI portal)

• http://www.etsi.org/ptcc(ETSI PTCC and testing issues)

• [email protected](BRAN Chairman)

For more information ...

Advanced Broadband Wireless Standards from ETSI and Co-operation with WiMAX

Documents

marconi communications

policyeach etsi member

rights reservedtransition

technical standards

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harmonised standards

member companies

regulatory bodies