AgilentLTE

Concepts of 3GPP LTE

Sonali Sarpotdar

16 Jan 2008

Agenda

• LTE Context and Timeline

• LTE major features

• Overview of the LTE air interface

• Agilent LTE design and test solutions

• Simulation

• Baseband

• Sources

• Analysis

Agenda

• LTE Context and Timeline

• LTE major features

• Overview of the LTE air interface

3GPP standards evolution (RAN & GERAN)

1999

2010

Release Commercial

introduction

Main feature of Release

Rel-99

2003

Basic 3.84 Mcps W-CDMA (FDD &

TDD)

Rel-4

Trials

1.28 Mcps TDD (aka TD-SCDMA)

Rel-5

2006

HSDPA

Rel-6

2007

HSUPA

Rel-7

2008+

HSPA+ (64QAM DL, MIMO 16QAM

UL). Many smaller features plus

LTE & SAE Study items

Rel-8

2009-10?

LTE Work item – OFDMA air interface

SAE Work item New IP core network

Edge Evolution, more HSPA+

LTE context and timeline

The many faces of LTE

• LTE is the 3GPP project name for the evolution of UMTS

• LTE is now linked with the development of a new air interface but the

evolution of UMTS via HSDPA and HSUPA is still happening

• The official terminology for the new LTE radio system is:

• Evolved UTRA / Evolved UTRAN

• Evolved UMTS Terrestrial Radio Access

• Evolved UMTS Terrestrial Radio Access Network

• Earlier names for this included:

• 3.9G

• HSOPA - Evolution of HSDPA/HSUPA with OFDM

• Super 3G

• This naming is not standard and may fade out but 3.9G is likely to stick

• For this paper LTE is assumed to be E-UTRA & E-UTRAN

3.9G _{cf 802.20}UMB _E-UTRALTE _EvolutionEDGE HSPA+ 802.16eMobile WiMAXTM 3.5G 3G HSUPA FDD & TDD IS-95B cdma HSCSD iMode 2.5G 2G GSM IS-136_TDMA PDC GPRS E-GPRS EDGE 802.11g IS-95A cdma IS-95B cdma IS-95C cdma2000 802.11a 802.11b 1xEV-DO Release B 1xEV-DO Release A WiBRO 1xEV-DO Release 0 W-CDMA FDD HSDPA FDD & TDD W-CDMA TDD TD-SCDMA LCR-TDD 802.16d Fixed WiMAXTM 802.11n 802.11h

Wireless evolution – five competing 3.9G systems

LTE in context

• LTE is just one of five major new wireless technology developments

• 3GPP LTE

• 3GPP HSPA+

• 3GPP Edge Evolution

• 3GPP2 UMB (similar to 802.20)

• IEEE WiMAX – (802.16e / WiBRO)

• All five systems share very similar goals in terms of spectral efficiency,

with the wider systems providing the highest single user data rates

• Spectral efficiency is primarily achieved through use of less robust

higher order modulation schemes and multi-antenna technology

ranging from basic Tx and Rx diversity through to full MIMO

• HSPA+ and Edge Evolution are natural extensions to existing

technologies

• LTE, UMB and WiMAX are new OFDM systems with no technical

precedent other than the early implementation of WiBRO which is now

a WiMAX profile.

LTE standards development timing

2005

2006

2007

2008

2009

2010

Rel-7 Study Phase

Rel-8 Work Phase

Test Specs

First UE certification? Core specs

drafted

• 3GPP plan @ Aug 2007; Final specs - Feb 08, Initial Conformance tests - Sept 08

• Timeline has slipped about 6 months but still considered a stretch goal by many

• Historically, test specs have been much more than 3 months after core specs but the

gap between core specs and conformance is consistently dropping

• UE certification not possible until after test implementation and validation

• Commercial release is hard to predict but is very unlikely before 2010

First Test Specs drafted

Commercial release?

Agenda

• LTE Context and Timeline

• LTE major features

• Overview of the LTE air interface

LTE major features

Feature

Capability

Access modes FDD & TDD – each with their own frame structure Variable channel BW 1.4, 3 , 5, 10, 15, 20 MHz

All bandwidths supported by FDD and TDD Baseline UE capability 20 MHz UL/DL, 2 Rx, one Tx antenna

User Data rates DL 172.8 Mbps / UL 86.4 Mbps @ 20 MHz BW (2x2 DL SU-MIMO & non-MIMO 64QAM on UL) Downlink transmission OFDM using QPSK, 16QAM, 64QAM

Uplink transmission SC-FDMA using QPSK,16QAM, 64QAM DL Spatial diversity Open loop TX diversity

Single-User MIMO up to 4x4 supportable

UL Spatial diversity Optional open loop TX diversity, 2x2 MU-MIMO, Optional 2x2 SU-MIMO

LTE major features

Feature

Capability

Transmission Time Interval 1 ms H-ARQ Retransmission

Time

7 or 8ms* (This is tight and one of the hardest specs to meet in baseband)

*under negotiation

Frequency reuse Static & semi-static (reuse per UE) Frequency hopping Intra-TTI: Uplink once per .5ms slot

Downlink once per 66μs symbol Inter-TTI Across retransmissions

Bearer services Packet only – no circuit switched voice or data services are supported
voice must use VoIP Unicast Scheduling

schemes

Frequency selective (partial band)

Frequency diversity by frequency hopping

Why did 3GPP want LTE?

• Much untapped potential in HSDPA + HSUPA (HSPA+)

• But some LTE requirements can’t be met by HSPA+

• LTE goal is to provide further benefits

• Spectrum Flexibility

• Higher Peak Data Rates with wider 20 MHz channel bandwidth

• OFDM Access better suited for Broadcast Services

• OFDM enables less complex implementation of Advanced

Antennas/MIMO Technology

• Reduced terminal complexity

• LTE itself has some less complex aspects

• But terminals will have to carry the legacy of GSM, GPRS,

W-CDMA and HSPA which increases overall complexity

LTE vs. HSPA+

Attribute

HSPA+ (Rel-8)

LTE targets

Peak Data Rate / 5 MHz sector in ideal radio conditions

DL – 42 Mbps UL – 10 Mbps

DL – 43.2 Mbps UL – 21.6 Mbps Peak Data Rate / 20 MHz sector

in ideal radio conditions

Not possible without multi-carrier

DL – 172.8 Mbps UL – 86.4 Mbps Cell Edge improvement

compared to HSPA Release 6

Evolved HSPA & LTE - DL – 3x to 4x; UL – 2x to 3x

All solutions will benefit from ongoing improvements to the radio interface such as UE RX diversity, equalization, interference cancellation; MIMO, higher order modulation etc.

Spectral Efficiency (real world)

Latency: End to End Ping Delay 40 ms Latency: Idle to Active Currently around 600ms

Goal to reduce to 100 ms

<100 ms

Flexible Bandwidth Utilization? 5 MHz unless multi-carrier is developed

1.4 MHz to 20 MHz

IMS TE MT UTRAN SMS-SC EIR TE MT Billing System* R Um GERAN WAG Uu HLR/AuC* HSS* R C Wn Wp Wu WLAN UE Ww Intranet/ Internet Wa Wm Wf Iu Gn Gb, Iu Gf Gr Gd Ga Gi Gn/Gp Gc SMS-GMSC SMS-IWMSC Wi OCS* SGSN SGSN

Note: * Elements duplicated for picture layout purposes only, they belong to the same logical entity in the architecture baseline.

** is a reference point currently missing Traffic and signaling

Signaling HLR/ AuC* 3GPP AAA Proxy Ga Gy CDF CGF* 3GPP AAA Server PCRF AF Rx+ (Rx/Gq) Gx+ (Go/Gx) OCS* UE P-CSCF Mw Cx Dx Wa Wg Gm SLF HSS* CSCF MRFP IMS-MGW Wo D/Gr Dw Mb PDG CGF* WLAN Access Network Wx Mb GGSN Wz Wd BM-SC Gmb Gi MSC Gs PDN ** Billing System* Wf Wy

Logical baseline architecture for 3GPP

23.882

Figure 4.1-1

The point

here is the

complexity,

gaps and

overheads

in existing

CS/PS

networks

Simplified LTE network elements and interfaces

S 1 S1 S 1 S1 X2 X 2

3GPP TS 36.300 Figure 4: Overall Architecture

MME = Mobile

Management

entity

SAE =

System

Architecture

Evolution

Logical high level architecture for evolved system

Evolved IP packet core with multi-RAT integration

23.882

Figure 4.2-1

S5b

Evolved Packet Core

WLAN 3GPP IP Access S2 non 3GPP IP Access S2 IASA S5a SAE Anchor 3GPP Anchor S4 SGi Evolved RAN S1 Op. IP Serv. (IMS, PSS, etc…) Rx+ GERAN UTRAN Gb Iu S3 MME UPE HSS PCRF S7 S6

* Color coding: red indicates new functional element / interface SGSN GPRS Core HSS - Home subscriber server IMS - IP multimedia subsystem Inter AS anchor -Inter access system anchor MME - Mobility management entity Op. IP Serv. -Operator IP service PCRF - Policy and charging rule control function UPE - User plane entity

WiMAX could connect here

LTE documents from the study phase (Rel-7)

The latest study phase technical documents can be found at:

•

www.3gpp.org/ftp/Specs/html-info/25-series.htm

• 23.882 System Architecture Evolution

• 25.912 Feasibility study for Evolved UTRA and UTRAN

• 25.913 Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN

(E-UTRAN)

• 25.813 Radio interface protocol aspects

• 25.814 Physical Layer Aspects for Evolved UTRA

Most of these are no longer being kept up to date now the

work has transferred to the 36-series (Rel-8) specifications

However these document still provide a useful overview that

may be difficult to find in the formal specifications

LTE 3GPP Specifications (Rel-8)

• After the LTE study phase in Rel-7, the LTE specifications

are defined in the 36-series documents of Rel-8

• There are six major groups of documents

• 36.8XX & 36.9XX Technical reports (background information)

• 36.1XX Radio specifications (and eNB conformance testing)

• 36.2XX Layer 1 baseband

• 36.3XX Layer 2/3 air interface signalling

• 36.4XX Network signalling

• 36.5XX UE Conformance Testing

• The latest versions of these documents can be found at

Agenda

• LTE Context and Timeline

• LTE major features

• Overview of the LTE air interface

LTE – Impε

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Orthogonal Frequency Division Multiplexing

…

Sub-carriers

FFT

Time Symbols 5 MHz Bandwidth Guard Intervals

…

Frequency

25.892 Figure 1: Frequency-Time Representation of an OFDM Signal

OFDM is a digital multi-carrier modulation scheme, which uses a large

number of closely-spaced orthogonal sub-carriers. Each sub-carrier is

modulated with a conventional modulation scheme (such as QPSK,

16QAM, 64QAM) at a low symbol rate similar to conventional single-carrier

modulation schemes in the same bandwidth.

Why OFDM for the downlink?

• OFDM already widely used in non-cellular technologies and was

considered by ETSI for UMTS in 1998

• CDMA was favoured since OFDM requires large amounts of baseband

processing which was not commercially viable ten years ago

• OFDM advantages

• Wide channels are more resistant to fading and OFDM equalizers are much

simpler to implement than CDMA

• Almost completely resistant to multi-path due to very long symbols

• Ideally suited to MIMO due to easy matching of transmit signals to the

uncorrelated RF channels

• OFDM disadvantages

• Sensitive to frequency errors and phase noise due to close subcarrier spacing

• Sensitive to Doppler shift which creates interference between subcarriers

• Pure OFDM creates high PAR which is why SC-FDMA is used on UL

• More complex than CDMA for handling inter-cell interference at cell edge

CDMA vs. OFDM

• CDMA

• All transmissions at full system bandwidth

• Symbol period is short – inverse of system bandwidth

• Users separated by orthogonal spreading codes

• OFDM

• Transmission variable up to system bandwidth

• Symbol period is long – defined by subcarrier spacing and

independent of system bandwidth

OFDM vs. OFDMA

LTE uses OFDMA – a variation of basic OFDM

• OFDM = Orthogonal Frequency Division Multiplexing

• OFDMA = Orthogonal Frequency Division Multiple Access

• OFDMA = OFDM + TDMA

User 1 User 2 User 3 Subcarriers S y m b o ls ( T im e )

OFDM

Subcarriers S y m b o ls ( T im e )

OFDMA

OFDMA’s dynamic allocation enables better use of the channel for multiple

low-rate users and for the avoidance of narrowband fading & interference.

LTE uses SC-FDMA in the uplink

Why SC-FDMA?

• SC-FDMA is a new hybrid modulation technique combining the low PAR

single carrier methods of current systems with the frequency allocation

flexibility and long symbol time of OFDM

• SC-FDMA is sometimes referred to as Discrete Fourier Transform Spread

OFDM = DFT-SOFDM

TR 25.814 Figure 9.1.1-1 Transmitter structure for SC-FDMA.

DFT

Sub-carrier _{Mapping insertion} CP

Size-NTX Size-NFFT

Coded symbol rate= R

NTX symbols

IFFT

Frequency domain Time domain

Comparing OFDM and SC-FDMA

QPSK example using N=4 subcarriers

The following graphs show how this sequence of QPSK symbols is represented in frequency and time

1, 1 -1,-1 -1, 1 1, -1 1, 1 -1,-1 -1, 1 1, -1 15 kHz Frequency f_c V Tim e OFD MA sym bol OFD MA sym bol CP OFDMA

Data symbols occupy 15 kHz for one OFDMA symbol period

SC-FDMA

Data symbols occupy N*15 kHz for 1/N SC-FDMA symbol periods

60 kHz Frequency fc V Tim e SC -FD MA sym bol SC -FD MA sym bol CP

OFDM modulation

QPSK example using N=4 subcarriers

1,1 +45° -1,-1 +225° -1,1 +135° 1,-1 +315° f₀ (F cycles) f₀+ 15 kHz (F+1 cycles) f₀+ 30 kHz (F+2 cycles) f₀+ 45 kHz (F+3 cycles)

One OFDMA symbol period

…

…

…

…

Each of N subcarriers is encoded with one QPSK symbol

N subcarriers can transmit N QPSK symbols in parallel

One symbol period

The amplitude of the combined four carrier signal varies widely depending on the symbol data being transmitted

With many subcarriers the waveform becomes Gaussian not sinusoidal Null created by transmitting

1,1 -1,-1 -1,1 1,-1 1,1 -1,1 1,-1 -1,-1 I Q

SC-FDMA modulation

QPSK example using N=4 subcarriers

To transmit the sequence: 1, 1 -1,-1 -1, 1 1,-1

using SC-FDMA first create a time domain representation of the IQ baseband sequence

+1 -1 V(Q) One SC-FDMA symbol period +1 -1 V(I) One SC-FDMA symbol period Perform a DFT of length N and sample rate N/(symbol period) to create N FFT bins spaced by 15 kHz

V,Φ

Frequency

Shift the N subcarriers to the desired

allocation within the system bandwidth

V,Φ

Frequency

Perform IFFT to create time domain signal of the frequency shifted original

1,1 -1,1

1,-1 -1,-1

Insert cyclic prefix between SC-FDMA symbols and transmit

Important Note: PAR is same as the original QPSK modulation 1,1 -1,1 1,-1 -1,-1 I Q

The LTE air interface

• Consists of two main components – signals and channels

• Physical signals

• These are generated in Layer 1 and are used for system

synchronization, cell identification and radio channel estimation

• Physical channels

• These carry data from higher layers including control, scheduling and

user payload

• The following is a simplified high-level description of the

essential signals and channels.

• eMBMS, MIMO and some of the alternative frame and CP

configurations are not covered here for reasons of time

Signal definitions

DL Signals Full name Purpose

P-SCH Primary Synchronization Channel Used for cell search and identification by the UE. Carries part of the cell ID (one of 3 orthogonal sequences). S-SCH Secondary Synchronization

Channel

Used for cell search and identification by the UE. Carries the remainder of the cell ID (one of 170 binary

sequences).

RS Reference Signal (Pilot) Used for DL channel estimation. Exact sequence derived from cell ID, (one of 3 * 170 = 510).

UL Signals Full name Purpose

RS (Demodulation) Reference Signal Used for synchronization to the UE and UL channel estimation

Channel definitions

DL Channels Full name Purpose

PBCH Physical Broadcast Channel Carries cell-specific information PDCCH Physical Downlink Control Channel Scheduling, ACK/NACK

PDSCH Physical Downlink Shared Channel Payload UL Channels Full name Purpose PRACH Physical Random Access Channel Call setup

PUCCH Physical Uplink Control Channel Scheduling, ACK/NACK PUSCH Physical Uplink Shared Channel Payload

Signal modulation and mapping

DL Signals Modulation Sequence Physical Mapping Power Primary Synchronization Signal (P-SCH) One of 3 Zadoff-Chu sequences 72 subcarriers centred around DC at OFDMA symbol #6 of slot #0 [+3.0 dB] Secondary Synchronization Signal (S-SCH)

Two 31-bit M-sequences (binary) – one of 170 Cell IDs plus other info

72 subcarriers centred around DC at OFDMA symbol #5 of slot #0

Reference Signal (RS) OS*PRS defined by Cell ID (P-SCH & S-SCH)

Every 6th _{subcarrier of} OFDMA symbols #0 & #4 of every slot

[+2.5 dB]

UL Signals Modulation Sequence Physical Mapping Power Reference Signal (RS) uth root Zadoff-Chu SC-FDMA symbol #3 of

Channel modulation and mapping

DL Channels Modulation Scheme Physical Mapping

Physical Broadcast Channel

(PBCH) QPSK

72 subcarriers centred around DC at OFDMA symbol #3 & 4 of slot #0 and symbol #0 & 1 of slot #1. Excludes RS subcarriers. Physical Downlink Control

Channel (PDCCH) QPSK

OFDMA symbol #0, #1 & #2 of the first slot of the subframe. Excludes RS subcarriers. Physical Downlink Shared

Channel (PDSCH)

QPSK, 16QAM,

64QAM Any assigned RB UL Channels Modulation Scheme Physical Mapping Physical Random Access

Channel (PRACH) QPSK Not yet defined Physical Uplink Control

Channel (PUCCH) BPSK & QPSK

Any assigned RB but not simultaneous with PUSCH Physical Uplink Shared

Channel (PUSCH)

QPSK, 16QAM, 64QAM

Any assigned RB but not simultaneous with PUCCH

Physical Layer definitions – TS36.211

Frame Structure

Ts = 1 / (15000x2048)=32.552nsec Ts: Time clock unit for definitions

Frame Structure type 1 (FDD/TDD)

FDD: Uplink and downlink are transmitted separately

TDD: Subframe 0 and 5 for downlink, others are either downlink or uplink

#0

#1

#2

#3

……….

_#18

_#19

One subframe

One slot, Tslot= 15360 x Ts = 0.5 ms

One radio frame, T_f= 307200 x Ts = 10 ms

Frame Structure Type 1 – generic view

Tim e Frequency 1 ra dio fram e = 10 m sec (307 200 x Ts ) #0 #1 #2 #3 #4 #5 #19 #18 #17 #16 Su b-fram e N_BWDL _subcarriers N_BWRB _{subcarriers (=12)} P o w e r

The minimum allocation of resources is one

Resource Block = 12 adjacent subcarriers for one

0.5ms slot 1 sl ot = 0.5 mse c

Frame Structure Type 1 (DL)

Slot / Subframe / Frame

N_symbDL _{OFDM symbols (=7 OFDM symbols @ Normal CP)}

Cyclic Prefix

160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048 (x Ts) 1slot = 15360 Ts

P-SCH - Primary Synchronization Channel S-SCH - Secondary Synchronization Channel PBCH – Physical Broadcast Channel

PDCCH – Physical Downlink Control Channel Reference Signal – (Pilot)

1 frame

1 sub-frame

1 slot

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

Frame Structure Type 1 (DL) – Physical Mapping

Frequency

QPSK 16QAM

64QAM P-SCH - Primary Synchronization Channel

S-SCH - Secondary Synchronization Channel PBCH – Physical Broadcast Channel

PDCCH – Physical Downlink Control Channel Reference Signal – (Pilot)

Frame Structure Type 1 (UL)

Slot / Subframe / Frame

N_symbDL _{OFDM symbols (=7 OFDM symbols @ Normal CP)}

Cyclic Prefix

160 2048 144 2048 144 2048 144 2048 144 2048 144 2048 144 2048 (x Ts) 1slot = 15360

1

0 2 3 4 5 6

Reference Signal (Demodulation)

1 slot

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

1 frame

1 0 2 3 4 5 6

1 sub-frame

0 1 2 3 4 5 6

Frame Structure Type 1 (UL) – Physical Mapping

Frequency Time 16QAM Reference Signal (Demodulation) QPSK 64QAM

Agenda

• LTE Context and Timeline

• LTE major features

• Overview of the LTE air interface

• Agilent LTE design and test solutions

• Simulation

• Baseband

• Sources

• Analysis

LTE development challenges

• Shortened time-plan for development and deployment

• Development in parallel with standards refinements

• Early requirement for full functional testing

• Interoperability testing likely to show up different interpretations of

standards

• Mix of FDD- and TDD-based testing

• System test for MIMO architecture

• Channel bandwidth up to 20MHz / 172.8 Mbps

• Component and device capabilities will be greater than network

capability

Agilent’s Current Measurement Solutions and

Plans for LTE - Commitment

Agilent will provide design and test tools across the R&D

lifecycle

• Support for early R&D in components, base station

equipment and mobile devices with design automation tools

and flexible instrumentation, based on current measurement

platforms

• Refine test solutions and introduce tools for product

integration as development progresses to initial functional

prototypes

Integrated Mobile

Test platform

New Platform for multiple serial lanes

LTE Products

2006

2007

2008

2009

2010

3GPP LTE UL/DL Signals

3GPP LTE UL/DL Analysis and Demodulation MIMO capability

ADS simulation

SW

Demod

Analysis SW

Signal

Generation

Signal

Analysis

Logic

Analysis

MIPI D_Phy Commercial Release Prototype Versions MXG MXA Basic Coded RT DigRF 89601A VSA Proto VSA

ADS Wireless Library for LTE

Explore and verify your designs

• Current Status

• Library of simulation components for the Agilent EESof Advanced Design System (ADS) to facilitate the generation and analysis of 3GPP LTE compliant downlink (DL) and uplink (UL) signals.

• First release Oct 2006. Major updates in Feb 07, May 07, Sept 07. • Based on latest physical layer specifications V8.0.0 *Sept 07). • Generated signals are spectrally correct and encoded, and can be

multi-channel, fixed-length, real-time etc. as required.

• Signals can be exchanged with alternative simulation platforms, and can be downloaded to, or uploaded from hardware for real-world signal generation and analysis.

• Received signals can be demodulated and analyzed.

• Next Steps

• Continue to follow developments in 3GPP specifications. Add/evolve signal coding and further develop both DL and UL transmitter

measurements (such as EVM, Constellation etc.). • Further commercial releases at regular intervals. • Working on TDD support

Advanced Design System Simulation environment

Example here is from IEEE 802.11a/g

ADS “Connected Solutions”

• Develop library elements for 3GPP LTE in order to build physical layer

models for both transmitter and receiver in software

• Links to test equipment for prototype verification

• Implement and deliver a design tool while standard

evolves phased implementation in close cooperation

with customer

Download Analyze RF Component or DUT

Digital Serial Stimulus / Analysis

• Current Status

• Introduced DigRF v3 products and solutions

• Bridge gaps between simulation, IC evaluation & handset integration. • The N4850A & N4860A digital probes designed for 1Gbps

• For LTE digital interfaces that > 1Gbps leverage existing multi GHz serial technology to support higher speed interfaces.

• Agilent is a MIPI member at Adopter level.

• Next Steps

• Support digital serial stimulus and analysis for other RF-IC to BB-IC interfaces, integrated with RF stimulus/analysis, to provide

comprehensive cross domain solutions. • Review the physical layer specifications for

other (public and vendor-specific) interfaces between the RF-IC and the BB-IC to guide LTE specific implementation decisions.

• Agilent is committed to providing test tools for DigRF v4.0.

N4850A 312Mbps DigRF v3 Digital Serial Acquisition Probe N4860A 312Mbps DigRF v3 Digital Serial Stimulus Probe

BB/RF Interface Stimulus / Analysis Overview

Two modes of operation

• Emulation: The stimulus and analysis pods

actively drive and terminate the BB/RF bus, thus

emulating the BB ASIC's interface. The test

equipment provides support for RF ASIC

configuration / control, and drives it with signal

payload data.

• Spying: The analysis pod passively monitors

the bus to collect data for further analysis. The

test equipment parses the traffic and presents

the transactions (XML-based protocol viewer)

and payload (89601A Vector Signal Analyzer).

BB ASIC TEST EQPT (emulation) RF ASIC BB ASIC TEST EQPT (spying) RF ASIC

RF-IC Validation

(DigRF example)

89601A Vector Signal Analyzer software

RF-IC

Signal Studio Signal Creation Software

N4850A Acquisition Probe N4860A Stimulus Probe Tx Rx

16900

Logic Analyzer

MXA Spectrum Analyzer

MXG Signal Generator

RF-IC / BB-IC Integration

(DigRF example)

DSP

DigRF v3.xx

89601A Vector Signal Analyzer

RF

Logic Analyzer

Oscilloscope

Spectrum Analyzer

RF

BB-IC RF-IC

MXG Signal Generator

Signal Studio

Signal Creation Software

DigRF

uC

DigRF_v3.xx

Vis Port

LTE Signal Generation

Signal Studio Software

User-friendly, parameterized and reconfigurable 3GPP LTE signal generation software for use in conjunction

with Agilent ESG-C or MXG RF Signal Generators.

E4438C (ESG E4438C (ESG--C)C) N5182A (MXG)

N5182A (MXG)

• Current Status

• Spectrally correct version available since April 07 • Fully coded version released recently

• Now based on TS 36.211 V8.0.0 – DL Physical channel framing

– Reference signal, Synchronization signal – PDSCH, PDSCH, PDCCH, PBCH

– UL Physical channel framing

– Reference signal (Demodulation and Sounding) – PUSCH, PUCCH, PRACH

LTE Signal Generation

N7624B Signal Studio V3.0.0.0 September 2007

Download now at:

www.agilent.com/find/signalstudio

Just released Signal

Studio V3.0.0.0.

Build your own

custom LTE signals

Based on the latest

V8.0.0 (Sept 07)

LTE physical layer

specifications

RF playback

requires instrument

license (free 14-day

trial license

LTE Parametric Signal Analysis

• Analyzes all LTE modulation types: BPSK,

QPSK, 16QAM, 64QAM, CAZAC, and

OSxPRS

• Covers all bandwidths: 1.4MHz (6RB) to

20MHz (96/100 RB)

• Handles UL and DL, normal and extended

Cyclic Prefix

• Advanced analysis of radio frame, subframe,

resource blocks, and channels

• Auto detection and demodulation of DL user

bursts

• P-SCH, S-SCH, PBCH, PDCCH, RS, PDSCH

and PUSCH analysis

• EVM = -50dB (measurement platform

dependent)

LTE Signal Analysis

Downlink Capabilities

(based on 36.211 V8.0.0)

• Synchronisation to ADS 2006U1(or U2).407 Dev 1 generated LTE Downlink signals

• Supports Antenna Port 0..3 RS pilot

subcarrier/symbol mappings per TS36.211 OS and PN9 PRS

• Supports latest PSCH using ZC root indices 25, 29, 34 for cell ID Groups 0, 1, 2 respectively.

• Auto detect / report RS Orthogonal Sequence • Auto detection of RS PRS

• Latest RS subcarrier antenna mappings

• PDCCH can occupy the first L OFDM symbols in first slot of subframe, where L<=3.

• User can configure PDCCH symbol allocations on a subframe-by-subframe resolution.

• Demod. user specified Slot# and OFDM symbol# • User definition of up to 6 PDSCH 2D Data Bursts for EVM analysis (format QPSK, QAM16, QAM64) • Downlink frequency lock range approximately

Analyzing OFDM impairments using 89601A

• This downlink

signals shows a

common OFDM

impairment where

the allocated

subcarriers have

an image

• The distortion that

create this image

was 0.1dB IQ gain

imbalance

• The lower trace

shows the

increased EVM at

the image

• Requirements will

be developed to

limit the image

Allocation

Image

LTE Signal Analysis

Uplink Capabilities

(based on 36.211 V8.0.0)

• Synchronisation to ADS 2006U1(or U2).407 Dev1 generated LTE Uplink signals

• Multiple resource block allocations restricted to sub carrier DFT sizes which are multiples of 2, 3 and 5 as per current 3GPP working

assumption.

• The DM RS Pilot symbol is located in 4th symbol (i.e. sym=3) of allocated slots.

• Demodulation of user specified SC-FDMA symbol# within a Slot of Radio Frame

• Assumes DM RS Pilot symbol contains Zadoff-Chu Sequence mapped to every subcarrier within allocated contiguous RB size.

• User definition of PUSCH two-dimensional Data Bursts for EVM analysis (format QPSK, 16QAM, 64QAM)

• Supports Half-Subcarrier-Shift = On/Off

LTE Signal Analysis - Measurements

• Sync Correlation

• Freq Error (Hz)

• IQ Offset (dB)

• EVM (%RMS and dB), EVM Peak

(%pk and sub carrier location)

• Data EVM (%rms and dB), EVM Peak

(%pk and sub carrier location)

• Pilot EVM (%rms and dB), EVM Peak

(%pk and sub carrier location)

• Common Pilot Error (%rms)

• Symbol Clock Error (ppm)

• CP Length

• Slot #, Symbol #

• Channel EVM table metrics

– Downlink supports P-SCH, S-SCH,

RS Pilot, PBCH, PDCCH, PDSCH

01 thru 06 (dB, %rms, %pk, Peak

Loc'n)

– Uplink supports DM Pilot, PUSCH

(dB, %rms, %pk, Peak Loc'n)

• Channel Power table metrics

– Downlink supports P-SCH, S-SCH,

RS Pilot, PBCH, PDCCH, PDSCH

01 thru 06 (dB relative to

un-boosted reference)

– Uplink supports DM Pilot, PUSCH

(dB relative to un-boosted

LTE Signal Analysis – Trace views

• Channel Freq Response (Adj. Diff Mag Spectral Flatness,

Magnitude, Phase, Group Delay)

• Common Pilot Error (Magnitude, Phase)

• Differential Pilot Error (Timing)

• EVM Spectrum (composite EVM displayed per Sub-Carrier, or per Resource

Block)

• EVM Time (composite EVM displayed per OFDMA/SC-FDMA symbol)

• Power Spectrum (composite Power displayed per Sub-Carrier, or per Resource

Block)

• Power Time (composite Power displayed per OFDMA/SC-FDMA symbol)

• Symbol Demod IQ Constellation/Vector

• Symbol Demod Spectrum Magnitude

• Symbol Demod Time Magnitude

• Symbol Data (Demodulated symbol bits represented as two hexadecimal

characters per sub carrier)

Spectrum Analyzer HW platforms

• PSA with 40MHz or 80MHz analysis BW

• Can be used as RF front end to external PC where

89601A VSA based LTE application is running

• MXA with 25MHz analysis BW

• Can be used as RF front end to external PC where

89601A VSA based LTE application is running

• Since MXA is a windows product, the 89601A software

can run inside the instrument

LTE Integrated Mobile Test Platform

RLC/MAC interface for protocol test Full LTE signalling stack

Protocol conformance test

GSM/GPRS, W-CDMA/HSPA 2x2 MIMO

Scalable single box solution

• 2G/3G/3.9G capable

• 20MHz BW

• 2x2 MIMO

• 2 cells

• RF parametric measurements

• Signalling Conformance Test

• RF Conformance Test

initial introduction: Mid-2008

Plan ned enha ncem ents RF conformance test RF parametric measurements

In summary – Agilent & LTE

• Support for early R&D in components, base station equipment, mobile devices

and network deployment with design automation tools and flexible

instrumentation, based on measurement platforms available today

Agilent will refine test solutions and introduce

tools for product integration as development progresses to initial functional

prototypes.

Agilent will be ready with manufacturing test

capability for early ramp-up Agilent will provide the tools needed for Service Provider deployment ADS Software Demod Analysis SW Signal Generation Signal Analysis Logic Analyzer AVAILABLE TODAY

* Used today for LTE development * Commitment – LTE specific features

* Used today for LTE development * Commitment – LTE specific Features

* Digital VSA tools available Today

Protocol Analysis Network Optimization Integrated mobile test platform AVAILABLE TODAY

* Commitment – LTE specific Features * Commitment – LTE specific Features

Agilent LTE Brochure

5989-6331EN