soft modem technology allpress-icera.pdfhspa hspa+ dc mimo lte 150mbps soft modem evolves...

LTE Focus Amsterdam

Soft Modem TechnologySteve Allpress, CTO and Co‐Founder Icera Inc.

9TH September , 2010

Copyright 2010 Icera Inc

LTE Focus Amsterdam

LTE Focus Amsterdam

Overview

• Introduction to Icera• Soft Modem Technology• Modem Performance• LTE and Multi‐RAT• Summary

Copyright 2010 Icera Inc 2

LTE Focus Amsterdam

Introduction to Icera


2G/3G/4G chipsets, firmware & ref designsVoice

P2P

R&D center

Sales & customer engineering center

300 employees located in 7 countries

Company timeline2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

CompanyFounded

First SiliconSampled

SoftBankC01SI

AT&TQuicksilver

AT&TLightning

AT&TTurbo

3.6 DPA

3.6 UPA& EDGE

7.2 UPA

7.2 UPA

21 HSPA+

LTEMulti‐RAT

HSPA+

LTE

0

500

1000

1500

2000

2500

2008 2009 2010 2011 2012 2013

Mon

thly Data Traffic (PetaB

ytes)

Mobile Data Traffic togrow by 66x by 2013

Explosion in Demand for Mobile Broadband

LTE Focus Amsterdam

Customer Portfolio

Netbook

TabletsSmartphones

2009+ 2010+ 2011+


USB sticks

Emerging Devices

Full

HalfLGA M2M

Icera‐powered modules available from Multiple vendors

7.2Mbps 21Mbps 50‐150Mbps42Mbps

LTE Focus AmsterdamCopyright 2010 Icera Inc 5

“Hard” versus Soft Modems

DSP

ARM11

I$D$

I$D$

I/O BLOCKS

PLLs

Clock distrib

DSPI‐Mem

Tx

RRC FilterRx RRCFilter

TX Rate Match

GSM/GPRSEDGE

DSPD‐Mem

HARQ processing

HSUPA

Turbo decoder

Rake Receiver

MMSEequalizer

De‐interleaver

Rate Matching

MRC Combiner

Control LogicControl

Control

PLLs

Ciphering

Scrambling

Viterbi decoder

P2P

Code Memory

Unified Data MemoryVector DXP®

Scalar DXP®

I/O BLOCKS

“HARD” MODEM

ICERA’S SOFT MODEM

LTE Focus Amsterdam

Soft‐Modem Technology

Advantages• Entire modem implemented

in software• Small silicon area

– Ease of support for multi‐RAT– Unified memory sub‐system

• Huge scope for algorithmic innovation– Adaptive Wireless™

Disadvantages• Entire modem implemented

in software– Software scheduling– Software validation

• Soft modem is not an “easy” modem


LTE Focus Amsterdam

Balance of Soft and Hard Modems


Instruction Decoding Unified Memory

Specificity of Data Path Width

Multiple-RAT

Arithmetic Operator Re-use

ASIC Design Flow

Algorithmic Innovation

Complexity of Standard

Reduced Verification Cost

Reduced Tape-Out Costs

LTE Focus Amsterdam 8

World’s First Commercial Soft Baseband

Vector DXP®

•whole PHY•2G/3G/LTE

Scalar DXP®

•Protocol Stack•Voice Codecs•Encryption

40nm silicon42Mbps HSPA 50Mbps LTE

No hardware accelerators

Memories

Memories

Processor

Processor

MemoriesLow

Speed Interfaces

USB

ROM


Decoupled Silicon Evolution

28nm

The perfect platform for developing agile and high-performance modems:• Rapid roadmap evolution in software, including post-sale upgrades.• Signal processing can adapt to optimum configuration; no hard-wired compromises or assumptions.

40nm65nm90nm

Baseband silicon evolves with process technology to offer more MIPs & more memory; fundamental architecture remains the same

3.6Mbps

42Mbps

21Mbps14Mbps7.2Mbps 50Mbps 100Mbps

28Mbps

HSPA HSPA+

DC

MIMOLTE

150Mbps

Soft modem evolves independently, always portable to the next platform


Soft Basebands are Smaller

Cat 14 (21Mbps) soft baseband in 65nm

Semiconductor InsightsCat8 (7.2Mbps) hard baseband in 65nm Cat8 (7.2Mbps) two-die hard

baseband, 65/130nm

Cat14 (21Mbps) hard baseband in 65nm

LTE Focus Amsterdam

Technology Enhancements

• Significant transceiver enhancements– All implemented as software upgrades to hardware platform

• Greatest gain from diversity– Type‐3i gain lifts minimum cell data rates

– 64‐QAM improving peak cell data rates


0

2000

4000

6000

8000

10000

12000

Roun

d‐Ro

bin Ce

ll Ca

pacity (k

bps)


Receive Diversity

...but even the snazziest ‘phones’ don’t yet have it

The humblest USB sticks have it...

So networks swamped by smartphone data have an easy capacity gain, at <<$1 cost


Cell Edge Performance

Away from the cell centre there are typically only 1 or 2 dominant interfering

cells

INTERFERER#1

INTERFERER#2

SERVING CELL

12% 37% 20% 31%

Distribution of users across cell

Cell edge Cell centre

High quality cat8 modem

(type3)

LTE Focus Amsterdam

Interference‐Aware Receiver

• Detects interfering cell‐site signals– Cancels sync channels– Suppresses adjacent cell‐site interference

• Significant throughput boost where it is most needed


3x

LTE Focus Amsterdam

Received Data Rate Distribution

• Concurrent, side‐by‐side drive‐test

• Two 14Mbps‐capable modems

• Average rates:– Soft Modem 1300 kbps– Hard Modem 640 kbps


0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 1000 2000 3000 4000 5000

Prob

ability Data Ra

te < Abscissa

Data Rate (kbps)

Soft Modem

Hard Modem

LTE Focus Amsterdam

CQI Report Histogram

• Signalled to node‐B• Gives logarithmic measure of SNR at turbo decoder input

• Reflects better channel conditions and/or better receiver performance


0

2

4

6

8

10

12

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30

Prob

ability (%

)

CQI Report

Soft Modem

Hard Modem

LTE Focus Amsterdam

LTE and Multi‐RAT

• High level of integration required– Limited utility of LTE “accelerators” or LTE standalone devices

• High compute requirements of LTE– High channel bandwidth processing– High data rates

• High power efficiency required over a wide‐range of use cases– VoIP– 100Mbps download


LTE Focus Amsterdam

Multi‐RAT Soft Modem Platform


ICE8061Multimode LTE/HSPA+/EDGE40nm processBaseband processor

ICE8260 or ICE8261Multimode LTE/HSPA+/EDGE130nm processTransceiver EDGE

WORLD’S FIRST TRI‐MODE SOFTWARE‐DEFINED MODEM

LTE Focus Amsterdam

LTE/HSPA/GSM Protocol Stack

Copyright 2010 Icera Inc. 19

CiPpp

GmmRabM

URlc

URlc

Llc

DsPpp

CiRt

VgMx

Sn

ApexAbGp

SmReg

Mmr MnSs MnCc MnSm

MmSs MmCc MmSm

(I)(U)SIM

AlSa

AlSi

RdGrr

GrrLlc(DTM mode)

UMac

Llc

GmmRd

RlcMac

DL/MDL

RlcMac Cpdcp

Llc

Gen

eric

Fu

nctio

nal I

/F

Rrc

GmmSim

GmmSm

SnSm

CRlc

CMac

Ccsd

RabmSm

GmmGan

GrrGan

CCSS SMS

SM

(G)RR

(G)(U)MM

L2

(U)SAT

RRC

UMAC

ERRC

MAC

EPDCP

RABM

GA-RC

GA-CSR

GA-PSR

CSDI

Grr

RTFDP/UFDP

GrrRc GrrLte

PPP

GAN Subsystem

CI

RD

URLC

SNDCP UPDCP

LLC

RLC

(G)Mph UMphPh

GrrMac

RdMac GL1 CPhy Phy EPhyECPhy

Anrm

L1Si

MUX

Application Background Layer

AMRCodec

IP

SubS

yste

m

TCP

UDP

RtL1

MnCb

GrrCb

L2Cb

UBMC

SM-CB

CbMc

Sat Cb PsdSms SmMmSim Csd

SS CC SMSMMCBSATSIM SM

ComPort

Application Layer

Non Access Stratum

Access Stratum

WPpp

GP

CcSs

Key

TMMData/Packet FlowTask Boundary

DeviceManager

L1Ctm

AlSu

ExCi

Ctm

GERAN UTRAN EUTRAN

CSR

GrrCsr

Csr

ECRlc

ECMac

ECpdcp

EUMac

RabMRrc

Eupdcp(C-Data)

2G

3G LTE


Multi‐RAT LTE on an HSPA Stick

Commercial HSPA sticks (Onda and Nokia)No hardware modificationsRe-flashed with LTE/HSPA+ software•Monolithic multimode protocol stack•Monolithic multimode PHY

World first LTE-3G-LTE handover, streaming video21Mbps HSPA+18Mbps LTE

Mobile World CongressFeb 2010

R&S and Anite multimode testers

LTE Focus Amsterdam

Summary

• Soft modems can outperform hard modems• Soft modem technology is now a key component of cellular industry– Multiplicity of standards– Complexity of standards

• Silicon technology now able to deliver– High compute performance– Low power consumption– Small die area


soft modem technology allpress-icera.pdfhspa hspa+ dc mimo lte 150mbps soft modem evolves...

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