1© 2014 The MathWorks, Inc.

Ask The Expert: LTE & WLAN System Toolbox

Trudy Rippel – Account Manager

Frank Vincze – LTE & WLAN System Toolbox Sales

Marc Barberis – Application Engineering Group

2

What’s LTE System Toolbox?

LTE and LTE-Advanced (Rel-8 through Rel-12)

Scope

– FDD/TDD

– Uplink/Downlink

– Transmitter/Receiver

~200 functions for physical layer (PHY) modeling

LTE Signal generation

ACLR/EVM measurement

Conformance Tests

3

What is WLAN System Toolbox?

Physical layer (PHY) modeling

L-SIG, HT-SIG, VHT-SIG-A, VHT-SIG-BOFDM, MIMO Equalization, STBC CombiningPacket detection, symbol timing correctionCoarse and fine frequency offset estimationPreamble signal decoders for L-SIG, HT-SIG, VHT-SIG-A, VHT-SIG-B fields

Transmitter & Receiver

Standard-compliant functions for the design, simulation, analysis, and testing of wireless LAN communications systems

Packet Error Rate, EVM

Spectral Emissions

Measurements

TGn, TGac

Propagation Channel

4

Use Cases

End-to-End Simulations

Measurements

Signal Generation

Packet successfully decoded!

Packet detected

VHT-SIGA Decoded

Signal Detection

Zynq SDR

RF Signal Generator

HW & Radio Connectivity

5

High-Level LTE Signal Generators

MATLAB Function

GUI-based

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Detailed Modeling

Fine

Mid-level

PDSCH Example

7

Supported WLAN Standards

Standard Bandwidth

(MHz)

MIMO Designation

802.11ac 20,40,80,

160

Up to 8 spatial streams,

MU-MIMO

VHT Very High Throughput

802.11n 20

40

Up to 4 spatial streams HT High Throughput

802.11g 20 N/A Non-HT

802.11a 20 N/A

802.11b 20 N/A

WLAN Toolbox uses the VHT, HT, Non-HT naming convention

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Quick Example : Generate WLAN Signal

cfgVHT = wlanVHTConfig

genCfg = wlanGeneratorConfig

VHTsignal = wlanWaveformGenerator([1 0 0 1], cfgVHT, genCfg);

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Signal Recovery with Field Decoding

Fine timing estimation

Fine frequency estimate

Channel estimation

Packet detection

Coarse frequency estimate

MCS

Nr of space streams

STBC, …

Payload duration PSDU length

MIMO

Channel

estimation

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Use Cases

End-to-End Simulations

Measurements

Signal Generation

Packet successfully decoded!

Packet detected

VHT-SIGA Decoded

Signal Detection

Zynq SDR

RF Signal Generator

HW & Radio Connectivity

11© 2014 The MathWorks, Inc.

Questions included in the invite

12© 2014 The MathWorks, Inc.

Q1. How do you interface with instruments or SDRs

from leading manufacturers?

13

Connecting to T&M InstrumentsInstrument Control Toolbox

RF Signal GeneratorLAN/USB/GPIB

▪ Generate LTE baseband signal in MATLAB

▪ Download to Signal Generator

LTE/WLAN System Toolbox

Signal Generation and Transmission

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LAN/USB/GPIB

Spectrum Analyzer LTE/WLAN System Toolbox

▪ Retrieve IQ data into MATLAB for analysis

▪ Perform visualization and analysis in MATLAB

Signal Acquisition and Analysis

Connecting to T&M InstrumentsInstrument Control Toolbox

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Hardware ConnectivityCommunications System Toolbox

USRP SDRZynq SDR

http://www.mathworks.com/products/communications/features.html

#hardware-connectivity-and-software-defined-radio

16© 2014 The MathWorks, Inc.

Q2. What type of interference can you model?

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Impairments in Communication System Toolbox

Communications Systems Toolbox lets you model

– MIMO multipath fading channels

– Additive noise

– Phase and Frequency offset

– Phase noise

– Non-linear amplifier

– IQ imbalance (and compensator)

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More Interferences & Impairments

Co- & Adjacent Channel

• UMTS, LTE, WLAN, satellite, or non-specific

Doppler

User-defined propagation environment

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802.11g Channel 6 with LTE Band 40 Interferer

2300-2400MHzWifi Channel 6: 2.437GHz

20© 2014 The MathWorks, Inc.

Q3. Which kind of analysis can you perform on

signals I have?

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Most Common Measurements

EVM

ACLR

Synchronization

Frequency Offset Estimation

Demodulation

Packet Detection

Preamble decoding (WLAN)

Communication-related measurements (scatter, eye, …)

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LTE Signal Information Recovery Example

Automatic synchronization

to the input signal

Demodulation of MIB

and Control Channel

>> SIB1RecoveryExample

Identified number of antennas and

PHICH configuration

Found cell ID and timing

Found cell bandwidth

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WLAN Blind Signal Detection

Searching for packet...

Packet #3 detected at index 23165

Estimated CFO: -63802.8 Hz

Decoding L-SIG...

LSIG EVM: 4.0% rms, 15.4% max

L-SIG check pass

Number of samples in packet: 14160

Attempting VHT-SIG-A decode for format detection...

VHT packet detected

Decoded VHT-SIG-A:

VHT-SIG-A EVM: 3.7% rms, 13.8% max

24© 2014 The MathWorks, Inc.

LIVE QUESTIONS

Submit your questions to the presenter in the chat panel…

25© 2014 The MathWorks, Inc.

THANK YOU!

Email: Trudy.Rippel@mathworks.com