lte-advanced webcast 2011-06-02

Copyright © 2011 Agilent Technologies

2011 Greater insight.Greater confidence.

“LTE-Advanced:Overcoming Design Challenges

for 4G PHY Architectures”

Greater insight. Greater confidence.Copyright © 2011 Agilent Technologies

Daren McClearnonProduct Marketing ManagerElectronic System-Level EDA

Wu HuanSystem Engineer,Beijing Wireless R&D Center

June 2, 2011



Agenda

Standards Overview• LTE-Advanced - New Features• LTE-Advanced - Channel Model

Introduction to Agilent SystemVue

Design Challenges• Working algorithmic reference• Flexible early verification & project NRE• Carrier Aggregation & RF stress• MIMO & Channel considerations• Verification increasing

Conclusion and Q&A

2



LTE-Advanced Requirement

Performance indicators LTERelease 8

IMT-Advanced LTE-AdvancedRelease 10

Peak data rate DL 300 Mb/s 1Gb/s 1 Gb/sUL 75 Mb/s 500 Mb/s

Peak spectrum efficiency [bps/Hz]

DL 15 [bps/Hz] 15 [bps/Hz] 30 [bps/Hz]UL 3.75 [bps/Hz] 6.75 [bps/Hz] 15 [bps/Hz]

Control plane latency < 100 ms 100 ms < 50 msUser plane latency < 5 ms 10 ms < Rel – 8 LTEScalable bandwidth support Up to 20 MHz Up to 40 MHz Up to 100 MHzVoIP capacity 200 Active users per

cell in 5 MHzUp to 200 UEs per

cell in 5 MHz3 times higher than

that in LTE

Cell spectrum efficiency(bps/Hz)

DL 2x2 1.69 2.44x2 1.87 2.6 2.64x4 2.67 3.7

UL 1x2 0.735 1.22x4 - 2.0

Cell edge spectrum efficiency(bps/Hz)

DL 2x2 0.05 0.074x2 0.06 0.075 0.094x4 0.08 0.12

UL 1x2 0.024 0.042x4 - 0.07

3



Release 10 Activity (LTE-Advanced)

LTE-Advanced Enhancements (relative to Release 8/9, LTE)

• Carrier aggregation (CA)- Contiguous and non-contiguous- Control channel design for UL/DL

• Enhanced multiple access scheme- Clustered SC-FDMA- Simultaneous Control and Data

• Enhanced MIMO transmission- Downlink 8 antennas, 8 streams- Uplink 4 antennas, 4 streams

Emerging Technologies(Release 10 & beyond)

• Relaying (multi-hop transmission)

• Coordinated multipoint (CoMP) transmission and reception

• Support for heterogeneous networks

• LTE self-optimizing networks (SON)

• HeNB and HeNB mobility enhancements

• CPE RF requirements

4



LTE Key Parameters (review)LTE-A builds on top of LTE Parameters and Frame Structure

UL adopts single carrier FDMA (SC-FDMA )• allows for commonality with the downlink OFDMA scheme

Access scheme

DL OFDMAUL SC-FDMA

Bandwidth 1.4, 3, 5, 10, 15, 20 MHzMinimum TTI 1 msSubcarrier spacing 15 kHzCyclic prefix length

Short 4.7 usLong 16.7 us

Modulation QPSK, 16-QAM, 64-QAMSpatial multiplexing Single layer for UL per UE

Up to 4 layers for DL per UEMU-MIMO supported for UL and DL

REV-090003r1 IMT-Advanced Evaluation Workshop 17 – 18 December, 2009, Beijing

5



LTE Frame Structure (review)

Supports both FDD and TDD frame structures

Stefan Parkvall et al “The Evolution of LTE towards IMT-Advanced,” Journal of Communications, Vol. 4, No. 3, April 2009

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

One slot

One radio frame 10ms

FDD

4 5 6 7 14 15 16 17 18 19

0 1 2 8 9 10 11 12

UL

DL fDL

fUL

fDL/UL

special subframe

one subframe

DWPTS GP UpPTS

TDDUL

DL

special subframe

6



20 MHzLTE terminal

LTE-Advanced terminal, 100MHz

(a) Contiguous carrier aggregation

… …(b) Non-contiguous carrier aggregation

20 MHzLTE terminal

LTE-Advanced terminal, 100MHz

LTE-A Enhancement #1: Carrier Aggregation• Wider bandwidth transmission using carrier

aggregation (CA) – support higher data rate– system bandwidths up to 100 MHz (5 component carriers

(CCs))

• Backward compatible with Rel-8 LTE when overlaid in IMT carrier bands.

• Supports both contiguous(figure a) and non-contiguous(figure b) carrier aggregation.

7



Downlink Multiple Access Scheme with CA

Downlink OFDMA with component carrier (CC) based structure

• One transport block is mapped within one CC

• Parallel-type transmission for multi-CC transmission (in good alignment with Release 8 specifications)

• Cross-carrier scheduling is possible– DL control channels (such as PDCCH,

PCFICH, and PHICH) are updated to support cross-carrier scheduling.

– Add a Carrier Indicator Field (CIF) to DCI.

Channel coding

Channel coding

Channel coding

Channel coding

HARQ HARQ HARQ HARQ

Modulation Modulation Modulation Modulation

Mapping Mapping Mapping Mapping

Transportblock 1

Transport block 2

Transport block 3

Transport block 4

20MHz CC1

One eNB

20MHz CC2 20MHz CC3 20MHz CC4

8



LTE-A Enhancement #2: Uplink Multiple Access Scheme

Uplink adopts Clustered DFT-S-OFDM• allows non-contiguous (clustered) groups of

subcarriers as well as contiguous subcarriers to be allocated for transmission by a single UE.

• support dynamic switching between Rel.8 single cluster transmission and Rel.10 clustered transmission

Simultaneous PUCCH and PUSCH transmission

DFTSub-

carrierMapping

IFFTCP

insertion

from DFT

ToIFFT

0

0

from DFT

ToIFFT

0

0

0

(a) Contiguous subcarriers allocation

(b) non-contiguous subcarriers allocation PUSCH PUSCH

PUCCH

CC CC

9



Uplink Multiple Access Scheme with CA

• Achieve wider bandwidth by adopting parallel multi-CC transmission to satisfy requirements for peak data rate while maintaining backward compatibility.

• Each transport block is mapped to a single component carrier.

• A UE may be scheduled over multiple component carriers simultaneously

Channel coding

Channel coding

Channel coding

HARQ HARQ HARQ

Modulation Modulation Modulation

RB mapping

RB mapping

RBmapping

Transportblock 1

Transport block 2

Transport block 3

CC1 20MHz

DFT DFT DFT

CC2 20MHz CC3 20MHz

Channel coding

HARQ

Modulation

RBmapping

Transport block 4

DFT

CC4 20MHz

One UE

10



Uplink PUSCH Processing in LTE-Advanced

Figure (a) shows the same channel coding procedure as LTE.

Data arrives to the coding unit in the form of a maximum of two transport blocks every transmission time interval (TTI) per UL cell.

Figure (b) shows the uplink physical channel processing including MIMO processing.

Up to two codewords can be supported.

Transport block CRC attachment

Code block segmentationCode block CRC attachment

Channel coding

Rate matching

Code block attachment

Data and control multiplexing

Channel coding

CQI

Channel Interleaver

Channel coding

RI

Channel coding

ACK/NACK

(a) Transport channel processing for UL-SCH (b) Overview of uplink physical channel processing

Scrambling Modulation mapper

Layer

MapperPrecoding

Resource element mapper

OFDM signalgeneration

Scrambling Modulation mapper


OFDM signalgeneration

codewords layers antenna ports

Transform precoder

Transform precoder

11



LTE-A Enhancement #3: multiple antenna transmission

• From 4 antennas/streams to 8 antennas/streams– Baseline being 4x4 with 4 UE Receive Antennas– Peak data rate reached with 8x8 SU-MIMO

• From 1 antenna/stream to 4 antennas/streams– Baseline being 2x2 with 2 UE Transmit Antennae– Peak data rate reached with 4x4 SU-MIMO

• Focus is initially on downlink beamsteering up to 4x2 antennas – SM is less attractive

• Challenges of higher order antenna transmission– Creates need for tower-mounted remote radio

heads– Increased power consumption– Increased product costs– Physical space for the antennae at both eNB and UE

UE

eNodeB

1, 2 or 4 transmitters and 2, 4 or 8 receivers

2, 4 or 8 transmitters and 2, 4 or 8 receivers

New for LTE-A

12



Enhanced Downlink MIMO Transmission Scheme

LTE DL MIMO uses antenna ports with cell-specific reference signals (CRS)LTE-Advanced DL MIMO uses antenna ports with UE-specific reference

signals (DM-RS)

Precoding

… …Layer Mapper



……

CRS0

CRSN-1

Precoding

… …Layer Mapper



……

DM-RS0

CSI-RSN-1

CSI-RS0

DM-RSM-1

(a) CRS-based MIMO

(b) DM-RS-based MIMO

CSI reference signals (CSI-RS)

13



• Geometry-based stochastic model• Similar to WINNER II MIMO channel model• S x U, N Clusters (multipath)

LTE-Advanced MIMO Channel Model

Array 1(S Tx elements)

Array 2(U Rx elements)

14



Array 1(S Tx

elements)

Array 2(U Rx

elements)

LTE-Advanced MIMO Channel Model

The impulse response matrix of the U x S MIMO channel

Where: – Ftx and Frx are antenna array response matrices

for the transmitter (Tx) and the receiver (Rx). – hn is the dual-polarized propagation channel response matrix for cluster n.

The channel from Tx antenna element s to Rx element u for cluster nis expressed as

( ) ( )∑=

=N

nn tt

1;; ττ HH

( ) ( ) ( ) ( )∫∫= ϕφφϕφτϕτ ddtt Ttxnrxn ,,;; FhFH

( ) ( )( )

( )( )

( )( ) ( )( )( ) ( )mnmn

stxmnurxmn

mnHstx

mnVstx

HHmnHVmn

VHmnVVmnT

mnHurx

mnVurxM

mnsu

tjrjrj

FF

aFF

tH

,,

,,1

0,,1

0

,,,

,,,

,,,,

,,,,

,,,

,,,

1,,

2exp 2exp2exp

;

ττδπυφπλϕπλ

φφ

ααα

ϕϕ

τ

−×

⋅⋅×

=

−−

=∑

15



LTE-Advanced MIMO Channel Model (cont’d)

• Stage 1 of 3 consists of two steps. 1. First, the propagation scenario is selected. 2. Then, the network layout and the antenna configuration are determined.

• In Stage 2 of 3, large-scale and small-scale parameters are defined. ChIR

generationPropagation parameter

generationUser defined parameters

Scenario selection

-urban macro-urban micro

-indoor-out2in-etc.

Network Layout

-BS & MS locations-velocities

Antennas

-# elements-orientations

-field patterns

Large scale parameters

-DS, AS, K-XPR

-shadowing-path loss

Multi-path parameters

-power, delay, AoA, AoD, etc.

Channel coefficient generation

ChIR

0.5

1

1.5

2

30

210

60

240

90

270

120

300

150

330

180 0

Antenna 1 gain patternAntenna 2 gain pattern

Antenna pattern

16



LTE-Advanced MIMO Channel Model (cont’d)

• In Stage 3, channel impulse responses (ChIRs) are calculated. Please note antenna pattern should be input to ChIR generation to calculate correlation matrix.

Coefficient generation:

Small scale parameter:

General parameters:

Set scenario, network layout and antenna

parameters

Assign propagation condition (NLOS/

LOS)Calculate path loss

Generate correlated large scale paramters

(DS, AS, SF, K)

Generate delaysGenerate cluster powers

Generate arrival & departure angles

Perform random coupling of rays

Draw random initial phases

Generate channel coefficient

Apply path loss & shadowing

Channel coefficient generation procedure

17



Agenda




Conclusion and Q&A

18



Unified architecture, verification tools for Layer 1 CommsAugments general purpose environments, or, stands on its own

PHY system integrationand verification

Cross-domain PHY modeling framework, for Model-Based Design

Complete a working PHY using combinations of Software, RF/BB Hardware, Simulation, and Measurements

Baseband AlgorithmsDataflow Simulation

RF Sys ArchitectureRF Simulators

Agilent SystemVue

PHY IP

TESTRF Hardware FlowsRFIC / MMIC

Hardware SiP / BoardHardware

Baseband Hardware Flows

GPP/ARMSoftware

DSP/ASSPSoftware

FPGA/ASIC/SoCHardware

19



SystemVue Environment – A Comms PHY “Cockpit”

20

W1918 LTE-Advnaced170 parts14 reference designs26 examples/TBs



.bitFiles

FPGASynthesis

Handwritten HDL

Custom IP

Integrated, top-down Comms ESL flow Cross-domain model-based design: RF, Comms, and C++/HDL

FPGA Target

REAL HARDWARE

HDL Simulator(s)

SIMULATED H/W

Dataflow Simulation

.m/C++ ALGORITHM

AlgorithmsC++, .m

MEASUREMENT, ANALYSIS

VSA softwareFlexDCA software

DIGITAL BITS, or MODULATED CARRIERS

MXG / ESG

Infiniium Scope

Logic Analyzer

MXA / PXA

Wideband arbs RF sensor

Target-neutralHDL Generation

System designRF Architecture

Baseband designPHY Reference

21

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Agenda




Conclusion and Q&A

22



• As a design progresses :System Architecture Algorithm RTL finished hardware– How many different IP references get written, used, thrown away? (NRE)– Are they compatible? Flexible? Updated? – Are they from a trusted source?– Can you re-use tests and scripting?

• Are the BB and RF teams working from the same IP references?

• Everyone needs some level of algorithm reference.

• Now able to deliver this IP throughout the design flow

Design Challenge #1 – Working Algorithmic Reference

23



SystemVue W1918 LTE-Advanced baseband libraryWhat is included?W1918 LTE-Advance BVL includes: Release 8

LTERelease 10

LTE-Advanced

Compiled dataflow simulation blocks 104 parts 66 parts

C++ “exploration” source code Optional, add-on not yet available

Packaged MIMO Sources/Receivers, w/GUI 10 ref designs 4 ref designs

Testbenches / Reference Examples 16 examples 10 (to date)

Works with existing instrument H/W Yes Yes

Works with Agilent 89600B VSA and SignalStudio software personalities

Yes Yes

Works with Agilent W1716 DPD Yes, integrated Yes, integrated

Works with Agilent W1715 MIMO Channelfor simulation-based fading

Yes Yes, extended for LTE-A

24



W1918 LTE-Advanced baseband verification library An open, “Golden Reference” for model-based design

25

Code-generationWin32 DLL

C++ (special option*)

User IP.m math code

C++ RTL

Test Vectors & scripts

HDL test bench

FPGA Development Environment

FPGA Hardware Test SYSTEMVUE OUTPUT VECTOR

FPGA VECTOR

SYSTEMVUE OUTPUT VECTOR

HDL VECTORSYSTEMVUE INPUT VECTOR

SYSTEMVUE INPUT VECTOR

*LTE source code exploration library (W1912) is a special option

Algorithmic Development Environment



Algorithmic lifecycle, for Model-Based Design

26

ALGORITHMIC MODELING…

THAT STAYS IN TOUCH WITH RF & SYSTEM-LEVEL

PERFORMANCE



SystemVue LTE-Advanced Library

Downlink Enhancement• Higher order DL MIMO: Up to 8 Tx 8 Rx Antennas• Support transmission to both R10 UEs and R8 UEs in a single source• Use DMRS to demodulate PDSCH• Precoding Codebook can be customized• Virtual Antenna Mapping: mapping matrix can be customized

Uplink Enhancement• Support Enhanced Uplink Multiple Access (clustered DFT-S-OFDM)• Support Uplink MIMO: up to 4 Tx and 4 Rx antennas

Carrier Aggregation• Support both inter and intra-band Carrier Aggregation

for both downlink and uplink

27



• How do you verify a standard that keeps Evolving? (the E in LTE-A)

• Configuring standard-compliant test benches (such as TS 36.101-104) requires Scripting, Non-Recurring Engineering (NRE) project costs, and Reference IP

• Many tests also require a completed, operational system, with closed feedback loop (e.g. – for Throughput testing).

• SystemVue libraries typically provide

– 5-15 of pre-configured testbenches, per wireless standard– Complete working reference PHY to start with.– Parameterized, fully-coded, modifiable Sources, Receivers, etc– Specialized measurements for Throughput, EVM, ACLR, etc

Design Challenge #2 – Flexible early verification & NRE

28



Dynamic Dataflow (simulation technology enhancement )Enables dynamic MAC-like changes during simulation, while preserving timed RF

Updated “throughput” status during simulation, as the LTE/LTE-A link adapts to an optimal PHY configuration

RF TXnonlinearity,phase noise

RF RXnonlinearity,

noise

8x8 MIMO

Channelantennas

fadingdoppler

interference

CODED MIMORCVR

CODED MIMO

SOURCE HARQ

Receiver requests dynamic Source changes Link converges to highest Throughput

29



LTE-Advanced DL ThroughputThroughput measurements, up to 8x8, w/active HARQ

• Up to 8x8 MIMO• Fading, RF impairments• Fully coded/decoded• Closed loop, with

Active HARQ

30

ACK/NACK

LTE-AdvancedChannel Model

LTE-AdvancedDownlink

MIMO source

LTE-AdvancedDownlink

MIMO Receiver



Hybrid Simulation/Test – Manually closing a loopLTE FDD UL Throughput Test (TS 36.141), or BER/BLER

Filter X

~

Filter A/D 1 2 3 4

DUGainDPDFilterX

~

A/D

RU DU

CPRI

Signal Generator

Signal Analyzer

SystemVue – Generates signal, then closes the loop

VSA 89600 waveform recordingSystemVue – LTE decode

Customer Hardware eNodeB receiver

STEP 1

STEP 2

31

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Leverage Simulation for R&D measurement applications that “fall between”

FILL HOLES

OFDM, MIMOLTE-Advanced

WNW, Defense

Jamming, InterfereClutter, TargetsRF, Phase NoiseCognitive environments

ThroughputCoded BER

DPD

MULTI-BOXCOORDINATION Digital vs. RF interfaces

Missing test coverageMissing user hardware

NON-STDWAVEFORMS

FADING,IMPAIRMENTS

32



Pre-configured LTE-Advanced MIMO Sources & Receivers3 Levels of User Interaction are supported

Simplified, tabbed GUI Scriptable schematic

Open, parameterized, reference design

MIMO DL Source subnetwork

High level GUI Detailed piecesor

33



Inside the SystemVue LTE-Advanced Downlink Source

• Up to 2 codewords in input• Up to 8 layers (antenna ports)

34



Tabbed GUI of the SystemVue LTE-Advanced DL Source

35



SystemVue LTE-Advanced Downlink TXMixed allocation of Rel10 and Rel8 RB’s

RB 0-4 allocated for R10 UE

RB 15-24 not allocated to any UE

RB 5-14 allocated for R8 UE

36



Enhanced Uplink Multiple Access Design and test challenges

• Clustered SC-FDMA increases PAR by a few dB adding to transmitter linearity challenges

• Simultaneous PUCCH and PUSCH also increases PAR• Both feature create multi-carrier signals within the channel

bandwidth• High power narrow PUCCH plus single or clustered SC-FDMA

creates large opportunity for in-channel and adjacent channel spur generation– May require 3 to 4 dB power amp backoff for Rel-8 PA– Some scenarios may require 10 dB backoff.

37



Inside the SystemVue LTE-Advanced Uplink Source

• Up to 2 codewords in input• Up to 4 layers (antenna ports)• Clustered DFT-S-OFDM

38



Tabbed UI of the SystemVue LTE-Advanced Uplink Source

39



SystemVue LTE-Advanced Uplink TX, w/2-layer MIMOClustered SC-FDMA

Cluster 1 PUSCH

PUCCH

Cluster 2 PUSCH

CCDF ~ 8dBAt 0.001%

The use of clustered SC-FDMA increases the PAPR above non-clustered SC-FDMA, but not as much as full OFDM which can exceed the PAPR of Gaussian noise

40




Derived from R4-100427 ftp://ftp.3gpp.org/tsg_ran/WG4_Radio/TSGR4_54/Documents/R4-100427.zipThis is a typical spectrum of a single carrier signal

+30

+20

+10

0

-10

-20

-30

-40

-50

-60

-70

-80

-90

Mag

(dB

m)

-3 -2 -1 0 1 2 3

Spectrum RBW = 100 kHz

LO Feedthrough

UnwantedImage

Spurs Spurs

Wanted signal: 2 RBs wide @1 channel edge

41

ftp://ftp.3gpp.org/tsg_ran/WG4_Radio/TSGR4_54/Documents/R4-101056.zip�




Derived from R4-100427 ftp://ftp.3gpp.org/tsg_ran/WG4_Radio/TSGR4_54/Documents/R4-100427.zipThe presence of two in-channel carriers creates 25 to 50 dB worse spurs

+30

+20

+10

0

-10

-20

-30

-40

-50

-60

-70

-80

-90

Mag

(dB

m)

-3 -2 -1 0 1 2 3

Spectrum RBW = 100 kHz

Spurs Spurs

Wanted signal: 1 RB @

2 channel edges

42

ftp://ftp.3gpp.org/tsg_ran/WG4_Radio/TSGR4_54/Documents/R4-101056.zip�



• Increased bandwidth of Carrier Aggregation drives PAPR to extreme levels

• Crest-Factor Reduction strategies are essential to offset this increase

• Increased RF bandwidth also exposes frequency-dependence and other analog degradations, which crosses multiple CC’s

• Combinations of several factors: Non-contiguous Carrier Aggregation, the multitude of possible RF Bands, and number of MIMO layers make these RF designs a true challenge.

• How do you translate real RF limitations back up to system-level performance? Can you correlate PHY simulations with measurements?

Design Challenge #3 – Carrier Aggregation stressing RF

43



Using SystemVue to make LTE-Advanced CA signalsScenario number

Deployment scenarioTransmission BWs of LTE-A carriers

# of LTE-A component carriersBands for LTE-A

carriersDuplex modes

1Single-band contiguous spec. alloc. @ 3.5GHz band for FDD

UL: 40 MHz

DL: 80 MHz

UL: Contiguous 2x20 MHz CCsDL: Contiguous 4x20 MHz CCs

3.5 GHz band FDD

2Single-band contiguous spec. alloc. @ Band 40 for TDD

100 MHz Contiguous 5x20 MHz CCsBand 40 (2.3 GHz)

TDD

4Single-band, non-contiguous spec. alloc. @ 3.5GHz band for FDD

UL: 40 MHz

DL: 80 MHz

UL: Non-contiguous 1x20 + 1x20 MHz CCsDL: Non-contiguous 2x20 + 2x20 MHz CCs

3.5 GHz band FDD

20 MHz CCs

44

80 MHz total



FDD and TDD LTE-Advanced Carrier Aggregation (DL)

Scenario Link Configuration PAPR of single CC,before aggregation

PAPR with CCs, after aggregation

Scenario 1 FDD DL 4x20 MHz CCs 8.45 dB 9.98 dB

Scenario 2 TDD DL 5x20 MHz CCs 9.17 dB 11.71 dB

Scenario 4 FDD DL 2x20+2x20MHz 8.38 dB 9.58 dB

FDD UL 20 + 20MHz 5.79 dB 6.86 dB

Scenario 1 FDD DL

Scenario 2 TDD DL

Scenario 4 FDD DL Scenario 4 FDD UL

45



Validating early Standards proposals (such as CA)

46

Early Algorithm validationEarly RF architecture validationTrusted 3rd party IP reference

Software-definedinstruments help with emerging standards

support

Leverage a system/algorithm tool for early architecture “reality check”“How far away is my existing design?” “Can I fix it cheaply in software?”



• Models/corrects for PA nonlinearities and memory effects

• Works with test equipment,and RF circuit co-simulation

• Achieves 15-20dB for 20MHz LTE; now being evaluated for LTE-A

• Quickly assesses the “correctability” of a PA

• Can model the “dirty” PAfor inclusion in Layer 1 link-level architecture studies

Digital Pre-Distortion (DPD)

47

6C-GSM

LTE

LTE-A

Memory Effects



Digital Pre-Distortion (DPD)

Additional DPD considerations• Wizard-based or manual UI

• Built-in signal generation

• LTE/LTE-A Crest-Factor Reduction

• Iterative model extraction, convergence

• Built-in links to calibrated test equip, AWGs, up/down converters, digitizers

• Memory Effect PA model based on measurements

Additional capabilities for the DPD Modeler• Modeling & Code Generation – Develop & deploy your own algorithms

• Scriptable, with external API links

• Encapsulate a methodology, create a custom UI

48



DPD of LTE-Advanced, using M9330A/M9392A 2x20MHz + 2x20MHz non-contiguous CCs, (100MHz signal BW)

49

For BW 140-250 MHz, Agilent M9392A is available

- 12bits ADC- up to 250MHz bandwidth- over 2.5GHz - may require wideband AWG

For BW < 140 MHz: Agilent PXA is recommended

- 14bits ADC- can reach down to -100dBm- greater DPD improvements

Sampling rate=245.76MHz



Simulation vs. Measurement DPD Extraction Approaches

50

External Trigger

Attenuator N5182 MXG

or E8257D PSGas external modulatorM9330A AWG if > 100 MHz

89600VSA

M9392A PXI VSA (>140MHz)or N9030A PXA (<140 MHz)

I,Q RF

RF DUT

SIMULATION-BASED DPD(predictive)

• ADS & GoldenGate Circuits as simulated RF DUTs- Complex loading, memory FX, dynamic behaviors

• NVNA X-parameter measurement model,- Great for smaller solid-state devices

X-parameters

RF DUTN5241,2 PNA-X

MEASUREMENT-BASED DPD

CO-SIM, MODELS

CO-SIM, MODELS

MODEL

ADS

GG



• MIMO “multiplicity” is adding to the verification effort; Do 8x4 and 8x8 provide the performance for an ROI?

• Virtual techniques (Agilent MIMO OTA approach, and simulation links from bottom-up EDA flows) can bridge gaps

• A surprising level of accuracy is attainable at the algorithm/architecture stage of a design

• Comparable algorithms can be used in both simulation and at-speed hardware faders; this symmetry can ease the transition to verification

Design Challenge #4 – MIMO and Channel considerations

51



W1715 MIMO Channel Model (for LTE-Advanced)Predictive, simulation-based fading, for up to 8x8 MIMO

WINNER II Channel Emulator Module

Scenario Selection/Network Layout/

Antennas

Input Ports

Output Ports

Large Scale & Small Scale Parameters Generation

Fading Coefficient Generation

Fading EngineTransmitting Signals

Faded Signals

User Define Parameters

52



LTE-Advanced Channel Modelling in SystemVuePredictive, simulation-based fading, from 3DEM analyses

from Agilent EMPro simulations

from Anechoic measurements

PHYSICAL ANTENNA PATTERNS

antenna pattern file 1

antenna pattern file 2

antenna pattern file N

FILES

. . .

W1715 MIMO CHANNEL MODEL

53



LTE-Advanced Channel Modelling in SystemVue

Antenna Patterns, loaded by human Throughput % vs. array rotation angle(with/without human)

54



SystemVue 2x2 MIMO Downlink ThroughputExperimental & Simulated results vs. Angle-of-Arrival

0 50 100 150 200 250 300 3500.84

0.86

0.88

0.9

0.92

0.94

0.96

0.98

1

1.02

AoA in degree

Thro

ughp

ut F

acto

r

Experiment ResultsSimulation Results

2x2 LTE-A Throughput %

Transition from Simulations to Test

DUT

55

It is possible to get early, realistic system-level results for MIMO

Incorporate preliminary designs for - Baseband PHY, and user IP- Industrial design & Antenna placement- RF transceivers (pre-tapeout)- Interference, and signaling environment

Challenge: Simulation speed, and amount of actual coverage testing



Verification dimensionality expanding vs.– BB PHY operating modes of LTE-Advanced, LTE, 3G, WLAN, MIMO– RF Spectral allocations/bands, and analog control settings– Semiconductor processes, battery, and environmental conditions

Scripting, regressions, IP exchange, and testbenches across domains

– RF models have been simplistic in Baseband in order to be fast

– Baseband Algorithms are dumbed down to static modes for CW RF– no frequency response, no memory effects, noise, or dynamic phenomena

The next generation of tools are addressing these challenges

Design Challenge #5 – Verification increasing dramatically

56



Band Uplink MHz Downlink MHz Width Duplex Gap1 1920 1980 2110 2170 60 190 1302 1850 1910 1930 1990 60 80 203 1710 1785 1805 1880 75 95 204 1710 1755 2110 2155 45 400 3555 824 849 869 894 25 45 206 830 840 865 875- 10 35 257 2500 2570 2620 2690 70 120 508 880 915 925 960 35 45 109 1749.9 1784.9 1844.9 1879.9 35 95 60

10 1710 1770 2110 2170 60 400 34011 1427.9 1447.9 1475.9 1495.9 20 48 2812 698 716 728 746 18 30 1213 777 787 746 756 10 -31 4114 788 798 758 768 10 -30 4015* 1900 1920 2600 2620 20 700 68016* 2010 2025 2585 2600 15 575 56017 704 716 734 746 12 30 1818 815 830 860 875 15 45 3019 830 845 875 890 15 45 3020 832 862 791 821 30 -41 7121 1447.9 1462.9 1495.9 1510.9 15 48 3324 1626.5 1660.5 1525 1559 34 -101.5 135.5

Points of note• There is a lot of overlap between

band definitions for regional reasons• The Duplex spacing varies from 30

MHz to 799 MHz• The gap between downlink and uplink

varies from 10 MHz to 680 MHz• Narrow duplex spacing and gaps

make it hard to design filters to prevent the transmitter spectral regrowth leaking into the receiver (self-blocking)

• Bands 13, 14, 20 and 24 are reversed from normal by having the uplink higher in frequency than the downlink

• Bands 15 and 16 are defined by ETSI (not 3GPP) for Europe only – these bands combine two nominally TDD bands to create one FDD band

LTE Frequency bandsFDD bands based on 36.101 va.2.0 Table 5.5-1

UplinkBand

DownlinkBand

Gap

Duplex spacing

Width Width

Frequency

57



Points of note• For TDD there is no concept of duplex

spacing or gap since the downlink and uplink frequencies are the same

• As such, the challenge of separating transmit from receive does not require a duplex filter for the frequency domain but a switch for the time domain

LTE Frequency bandsTDD bands based on 36.101 va.2.0 Table 5.5-1

Band Uplink MHz Downlink MHz Width

33 1900 1920 1900 1920 20

34 2010 2025 2010 2025 15

35 1850 1910 1850 1910 60

36 1930 1990 1930 1990 60

37 1910 1930 1910 1930 20

38 2570 2620 2570 2620 50

39 1880 1920 1880 1920 40

40 2300 2400 2300 2400 100

41 2496 2690 2496 2690 194

42 3400 3600 3400 3600 200

43 3600 3800 3600 3800 200

TransceiveBand

Width

Frequency

58



Future LTE/UTRA Frequency bands

The work on defining new frequency bands shows no sign of slowing up. These are the bands currently being considered by 3GPP:• Band 22 3410/3490 + 3510/3590 – UMTS/LTE 3500 MHz• Band 23 2000/2020 + 2180/2200 - S band additional terrestrial

component (ATC) of the mobile satellite systems (MSS)• Band 25 1850/1915 + 1930/1995 - Extended 1900 band – has

issues with GPS co-existence• Band 26 814/849 MHz + 859/894 – Extended 850 upper band• Band 27 806/824 + 851/869 – Extended 850 lower band

Other possibilities identified by the ITU:• 3.6-4.2 GHz• 450−470 MHz• 698−862 MHz• 790−862 MHz band (European digital dividend)• 4.4-4.99 GHz band

59



Fast Circuit Envelope (FCE) Verification Modeling

• FCE behavioral model is exported from RFIC circuit tools

• Runs native at the system-level in seconds, without needing EDA licenses

• Accounts for– Power-dependence– Frequency-dependence– Nonlinear memory effects– Frequency translation– ZeroIF/DC and RF carriers– Multiple I/O ports– Internal nodes

60

1000’s of analog transistors



Fast Circuit Envelope (FCE) Verification ModelingExample: FCE model used in an LTE Uplink test

Coded LTE UL5 MHz sourceSystemVue W1910/W1918 library

RFIC CMOS PA “FastCircuitEnvelope” model

Exported from GoldenGate

89600 VSA LTE demod

TUNE MODE

61

SCRIPTABLE ENVIRONMENTSCRIPTABLE PARAMETERS



Reliable system-level performance in seconds.

Pout = +19.3dBm, ACLR=23dBcCPU time = 3 sec (150k points)

Pout = +10.6dBm, ACLR=37dBcCPU time = 3 sec (150k points)

Nominal LTE result (0.4% EVM) LTE result – Compressing PA (20% EVM)

62



Deepest Insights: Direct circuit envelope co-simulation

I,Q

CLOSED-LOOP LTE UL

Throughput

RFIC environmt(remote Linux)

Upconvert/TX RFIC

RFIC environmt(remote Linux)

LowNoise Amp RFIC

RF RF RF

• Dynamic RF behavior• Standards-compliant• High accuracy• Directly uses the

design databases (not an indirect model)

63



Other approaches: Native RF System modeling Bringing RF System Architectures up to the PHY-level

Drag & DropDataflow modeling “on the fly”

From X-parameters

• Dedicated simulator for RF system architecture• Local RF analog effects (e.g. - X-parameters)• Drag &drop the whole RF chain into Dataflow• Able to do MIMO and ZeroIF architectures

To PHY system performanceTo RF System

Architectures

To PHY-level Systems



Agenda




Conclusion and Q&A

65



System-level tools and LTE-Advanced algorithmic libraryFlexible PHY algorithm reference from Concept to R&D Test

• Accelerate your Physical Layer (PHY) design process

• Save time with a trusted, open, independent IP reference

• Validate BB & RF integration early

• Streamline verification and NRE

• Fill strategic gaps using simulation

• Interoperate with test equipment, even while the Standard evolves

• Re-use the same Agilent assets throughout process

66



LTE-Advanced PHY presents significant new BB and RF design challenges

The EDA tools are also providing significant new capabilities to address these challenges. What was shown today is already available.

Seen today:– “instrument grade” Standards IP reference, usable throughout the design process– Modular top-down ESL design approach across both Baseband and RF domains– High-performance measurement and modeling techniques – Open SW/HW platform, with single-vendor worldwide apps & support

Visit us at regional Agilent seminar tours and industry trade shows, or on the web at http://www.agilent.com/find/eesof-systemvue-lte-advanced

Conclusion

67

http://www.agilent.com/find/eesof-systemvue-lte-advanced�



Questions?

68



You are invited – July 7

You can find more webcastswww.agilent.com/find/eesof-innovations-in-edawww.agilent.com/find/eesof-webcasts-recorded

Paul ColestockRF-MS Product Manager

George EstepRF-MS Application

Development Engineer

http://www.agilent.com/find/eesof-innovations-in-eda�

http://www.agilent.com/find/eesof-webcasts-recorded�



App Notes and Videos Referenced in this presentationSlide Agilent Literature

numberTitle/Description

4 5990-6706EN Introduction to LTE-Advanced14 Webcast

EEtimes“Theories, Techniques, and Validation of Over-The-Air (OTA) Test Methods for Evaluating the Performance of MIMO Handsets” (September, 2010)

15,55 5990-6535EN MIMO Channel modeling with SystemVue24 5990-8135EN SystemVue LTE-Advanced Library25 5990-3357EN LTE Reference Vector (whitepaper on model-based design methodology)25 YouTube video “Model Configurations for Easy Control of Model Polymorphism”

http://www.youtube.com/watch?v=LEEibGvIDvc

27 5990-7146EN Using SystemVue LTE-Advanced Signal Generation and Measurement31 5990-6202EN SystemVue for LTE Throughput46 5990-7757EN SystemVue for “Design-Validate-Test” (tutorial)48 5990-6534EN Using SystemVue for Digital Pre-Distortion48 Webcast

5990-6742EN“4G For Everyone: Extended RF Performance with Digital Pre-Distortion”

48 5990-7818EN “Making Digital Pre-Distortion Fast and Practical for all Engineers”61 YouTube video “Fast Circuit Envelope Models for RFIC verification”

http://www.youtube.com/watch?v=7k8TS2Due70

61 July 2011 webcast “A Model-based approach to System-Level RFIC Verification”http://www.agilent.com/find/innovations-in-EDA

70

For Agilent literature on the web, replace the digits in http://cp.literature.agilent.com/litweb/pdf/xxxx-xxxxxx.pdf with the literature number

http://cp.literature.agilent.com/litweb/pdf/5990-6706EN.pdf�

http://www.eetimes.com/electrical-engineers/education-training/webinars/4205845/Theories--Techniques--and-Validation-of-Over-The-Air--OTA--Test-Methods-for-Evaluating-the-Performance-of-MIMO-Handsets�




http://www.youtube.com/watch?v=LEEibGvIDvc�







http://www.youtube.com/watch?v=7k8TS2Due70�

http://www.home.agilent.com/agilent/eventDetail.jspx?cc=US&lc=eng&ckey=1997175&nid=-34360.0.02&id=1997175�

http://www.agilent.com/find/innovations-in-EDA�

http://cp.literature.agilent.com/litweb/pdf/xxxx-xxxxxx.pdf�






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