Doc.: IEEE 802.22-06/0076r0 Submission Kyutae Lim, Georgia Tech May 2006 Slide 1 Cognitive Radio System Testbed Demonstration Dr. Kyutae Lim ([email protected])

May 2006

Slide 1

doc.: IEEE 802.22-06/0076r0

Submission Kyutae Lim, Georgia Tech

Cognitive Radio System Testbed Demonstration

Dr. Kyutae Lim ([email protected])Associate Director of Technology

Georgia Electronic Design Center, www.gedcenter.org

Georgia Institute of Technology

May 2006

Slide 2

doc.: IEEE 802.22-06/0076r0


Cognitive Radio Testbed Overview

May 2006

Slide 3

doc.: IEEE 802.22-06/0076r0


Cognitive Radio Testbed

• Cognitive Radio Testbed was built in Georgia Electronic Design Center, Georgia Tech, Atlanta, GA.

• Perform the real time demonstration of various operations in CR system.

• Perform the industrial level of evaluation for PHY/MAG and Sensing Technologies.

• CR Testbed has flexibility in H/W and S/W.

• Testbed configuration and test procedure can be set by WG and Tiger team.

• We hope CR testbed to contribute for forging IEEE 802.22 Standard.

May 2006

Slide 4

doc.: IEEE 802.22-06/0076r0


DTV Sig Gen

Vector Sig Gen

AMP

TV Antenna

ADC : Data Acquisition

Spectrum Analyzer

Equipment Control

Signal Generation

Spectrum Sensing

Component Control

DisplayControl

Received sig.Analysis

Testbed Control : MATLAB

4 CH DACReceiverModule

Vector Signal Analyzer

DTV Test Receiver

Signal Generation Signal Reception

CR Testbed System Configuration

May 2006

Slide 5

doc.: IEEE 802.22-06/0076r0


Photo of Cognitive Radio Testbed

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

DTV monitorDTV

monitorMain

ControlMain

ControlRec. signalspectrum

Rec. signalspectrum

Constellation(OFDMA)

Constellation(OFDMA)

RF receiver module

RF receiver module

Vector signal analyzer

Vector signal analyzer

Spectrum Analyzer

Spectrum Analyzer

Vector signal generator

Vector signal generator

Broadcast sig. generator

Broadcast sig. generator

DAC/ADC/ComputerDAC/ADC/Computer

May 2006

Slide 6

doc.: IEEE 802.22-06/0076r0


System SpecificationName Specification

SMU 200A• Vector Signal Generator • Dual RF path – A (100 kHz ~ 6 GHz), B (100 kHz ~ 3 GHz)• I/Q baseband modulation bandwidth – 56 MHz

FSQ 40• Vector Signal Analyzer• RF input – 20 Hz ~ 40 GHz• Standard – GSM/EDGE, FM, CDMA2K, Bluetooth, WLAN, WiMax

SFU

• TV Signal Generator• RF output – 100 kHz ~ 3 GHz• Standard

– Digital TV – ATSC, DVB-T/H/C/S, DMB-T, DIRECTV, T-DMB/DAB– Analog TV, Arbitrary signal

• Test stream generator• Noise – AWGN, phase noise, impulsive noise• Fading – static path, pure dopler, rayleigh, rice, const. phase

Tuner• RF input – 50 ~ 878 MHz• IF out at 44 MHz / 6-MHz SAW filter can be bypassed• NF: 8 dB / RF VGA gain control: -12 ~ 38 dB

DAQ (ADC)

• PCI-interface• Dual channel / 12-bit resolution• Max. 400 MSample/sec• Input Dynamic Range : 100 mV ~ 5 V

DAC• PCI-interface• 4 channel / 12-bit resolution• Max. 300 MSample/sec

EFA• TV Test Receiver• ATSC/8VSB Demodulation

May 2006

Slide 7

doc.: IEEE 802.22-06/0076r0


Demo.1 : Cognitive Radio System Concept

Purpose : Basic CR operation principle

Spectrum Sensing

Co-existance of Incumbent and WRAN

Interference mitigation

Frequency agile operation

May 2006

Slide 8

doc.: IEEE 802.22-06/0076r0


DTV Sig Gen

Vector Sig Gen

AMP

TV Antenna


Spectrum Analyzer

Equipment Control

Signal Generation

Spectrum Sensing

Component Control

DisplayControl





DTV Test Receiver


Testbed Configuration: Demo.1

May 2006

Slide 9

doc.: IEEE 802.22-06/0076r0


Spectrum Sensing (TV signals only)

May 2006

Slide 10

doc.: IEEE 802.22-06/0076r0


WRAN Interferer (overlapped)

WiMax signal used as WRAN

May 2006

Slide 11

doc.: IEEE 802.22-06/0076r0


OFDMA Constellation / EVM

OFDMA communication failed.No constellation.EVM does not meet the criteria

May 2006

Slide 12

doc.: IEEE 802.22-06/0076r0


TVs-WRAN Co-Existence (WRAN in vacant channel)

May 2006

Slide 13

doc.: IEEE 802.22-06/0076r0



OFDMA communication working well.Good constellation.EVM meet the criteria

May 2006

Slide 14

doc.: IEEE 802.22-06/0076r0


Dynamic Frequency Switching - I- New primary user signal into the WRAN channel -

May 2006

Slide 15

doc.: IEEE 802.22-06/0076r0



Communication failed.

May 2006

Slide 16

doc.: IEEE 802.22-06/0076r0


Dynamic Frequency Switching - II- WRAN signal move to another vacant channel -

May 2006

Slide 17

doc.: IEEE 802.22-06/0076r0



Communication in work.

May 2006

Slide 18

doc.: IEEE 802.22-06/0076r0


Demo.2 : Evaluation of Spectrum Sensing Technology

Purpose : Verifying Various Spectrum Sensing Technologies

Generating Spectrum Environment

Energy Detection: MRSS

Feature Detection: AAC

May 2006

Slide 19

doc.: IEEE 802.22-06/0076r0


DTV Sig Gen

Vector Sig Gen

AMP

TV Antenna


Spectrum Analyzer

Equipment Control

Signal Generation

Spectrum Sensing

Component Control

DisplayControl





DTV Test Receiver



May 2006

Slide 20

doc.: IEEE 802.22-06/0076r0


Dual Sensing Strategy (presented Mar 06)

Energy Detectionfor wide band

(Analog, RSSI, MRSS, FFT…)

Begin Sensing

Fine/Feature Detection for single channel

End Sensing

occupied?Y

N

MAC(Select

single channel)

FFT CSFDField Sync

OptimumRadiometer

Multi-cycleDetector

AACSpectral

Correlation

Spectrum Usage

Database(BS) ATSC

Segment Sync

May 2006

Slide 21

doc.: IEEE 802.22-06/0076r0


Input Signal Spectrum / Time-domain Waveform

May 2006

Slide 22

doc.: IEEE 802.22-06/0076r0


Coarse MRSS

May 2006

Slide 23

doc.: IEEE 802.22-06/0076r0


Fine MRSS with Threshold Detection

May 2006

Slide 24

doc.: IEEE 802.22-06/0076r0


AAC for OFDM (WLAN 802.11a)

Get two clues (due to short and long preamble) !!

May 2006

Slide 25

doc.: IEEE 802.22-06/0076r0


An Example of Scheduling Algorithm for DFH

• A WRAN system maintains two channels (operating channel and candidate channel)

• If WRAN BSes can communicate each other to schedule the time switching to the candidate channel, collision can be completely avoided.

– Even if collision occurs on the candidate channel, it is only in very short time (about quite time).

WRAN A

Channel 1

Channel 2

Channel 3

WRAN B

May 2006

Slide 26

doc.: IEEE 802.22-06/0076r0


Demo.3 : Evaluation of protecting Incumbent user from WRAN signal

Generation of various fading environment

DTV Signal quality measurement in Fading

Coexistence of DTV and WRAN

Signal quality measure for DTV and WRAN

May 2006

Slide 27

doc.: IEEE 802.22-06/0076r0


DTV Sig Gen

Vector Sig Gen

AMP

TV Antenna


Spectrum Analyzer

Equipment Control

Signal Generation

Spectrum Sensing

Component Control

DisplayControl





DTV Test Receiver



May 2006

Slide 28

doc.: IEEE 802.22-06/0076r0


ATSC Test 1 – Fading (1)

• ATSC with Fading channel environment

• ATSC– Ch. 39 (center freq: 623 MHz)– Level: -10 dBm– Fading

• Rayleigh (Pass loss: 3 dB, freq ratio = 1.00)• EASY3 for DTV test

• Number of DTV signals and Fading parameters can be easily adjusted

May 2006

Slide 29

doc.: IEEE 802.22-06/0076r0



May 2006

Slide 30

doc.: IEEE 802.22-06/0076r0


Signal quality can be measured


May 2006

Slide 31

doc.: IEEE 802.22-06/0076r0


ATSC Test 1 – Fading (4)``````````````````````````````````````````````````````````````````````````````````````````````````````````````` ` `Various graphs enables signal quality analysis for DTV signal

May 2006

Slide 32

doc.: IEEE 802.22-06/0076r0


ATSC Test 2 – w/ WiMax (1)

• ATSC with Fading plus OFDMA signal to the adjacent channel

• ATSC– Ch. 39 (center freq: 623 MHz)– Level: -10 dBm– No fading

• WRAN (WiMax signal is used)– Freq: 616.5 MHz, BW: 7 MHz– Level: 0 dBm

May 2006

Slide 33

doc.: IEEE 802.22-06/0076r0


ATSC Test 2 – w/ WRAN (2)• Spectrum

WiMax

ATSC

WiMax Mask

May 2006

Slide 34

doc.: IEEE 802.22-06/0076r0


ATSC Test 2 – w/ WRAN (3)

May 2006

Slide 35

doc.: IEEE 802.22-06/0076r0


Signal quality is little bit degraded due to OFDM signal at adjacent channel


May 2006

Slide 36

doc.: IEEE 802.22-06/0076r0



OFDM signal

May 2006

Slide 37

doc.: IEEE 802.22-06/0076r0



• OFDM (WiMax) performance Still OK!

May 2006

Slide 38

doc.: IEEE 802.22-06/0076r0


Summary

• CR Testbed has built in GEDC, Georgia Tech– Maximum H/W flexibility– Full S/W control: MATLAB– Easy to expand for evaluating Sensing, Interference, MAC, PHY …

• CR Testbed has been demonstrated– CR Concept and frequency agile operation– Spectrum sensing technology evaluation– Emulation of various fading channel environment– Evaluation of WRAN signal to interfere DTV reception

May 2006

Slide 39

doc.: IEEE 802.22-06/0076r0


Suggestion

• Realistic spectrum environment can generated repeatedly.• The testbed can be customized to perform various

test/evaluation.• The parameters and figure-of-merit can be defined by WG.• Standard procedure for evaluation can be defined by WG.

• Let’s use this testbed for standard evaluation platform for PHY and Sensing technology !!!

Doc.: IEEE 802.22-06/0076r0 Submission Kyutae Lim, Georgia Tech May 2006 Slide 1 Cognitive Radio System Testbed Demonstration Dr. Kyutae Lim ([email protected])

Documents

wran slide

georgia tech

060076r0 submission

wran channel slide

vacant channel slide

vacant channel slide

wran signal

wimax signal