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
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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
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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
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High-Level LTE Signal Generators
MATLAB Function
GUI-based
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Detailed Modeling
Fine
Mid-level
PDSCH Example
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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?
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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.
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