Michael Timmers, Sofie Pollin, Antoine Dejonghe, Liesbet Van der Perre, and Francky Catthoor Katholieke Universiteit (K.U.) Leuven IEEE Transactions on Vehicular Technology, TVT 2010

Page: 2 WMNL Introduction Conclusion Multichannel MAC protocol for CR networks (MMAC-CR) Multichannel MAC protocol for CR networks (MMAC-CR) Performance Evaluation

Page: 3 WMNL Introduction Conclusion Multichannel MAC protocol for CR networks (MMAC-CR) Multichannel MAC protocol for CR networks (MMAC-CR) Performance Evaluation

Page: 4 WMNL  Defense Advanced Research Projects Agency (DARPA)  Only 2% spectrum are used at a given time and location.  Federal Communications Commission in the United States (FCC)  15%~85% of the licensed spectrum remains unused at a given time and location.  White holes  A more flexible allocation strategy could solve the spectrum scarcity problem.

Page: 5 WMNL  Cognitive Radio (CR) Networks  Primary User (or Licensed User)  Has a license to operate in a certain spectrum band.  Secondary User (or Unlicensed User)  Has no spectrum license.  Additional functionalities are required to share the license spectrum band.

Page: 6 WMNL  Primary User (or Licensed User)  Has a license to operate in a certain spectrum band.  Secondary User (or Unlicensed User)  Has no spectrum license.  Hence, additional functionalities are required to share the license spectrum band.

Page: 7 WMNL StandardPurpose IEEE SCC41 下世代無線頻寬管理系統 IEEE 結合數位電視頻道 (TV channel) 之感知無線通訊系統 IEEE k 開發 Wi-Fi 系統具備量測、回報、與辨識之頻寬使用 IEEE y 於 MHz 頻帶之競爭式感知無線通訊協定 IEEE h 支援 WiMAX 系統使用免執照 (License-exempt) 之通訊協定

Page: 8 WMNL  Multichannel advantages over single-channel  Reduce interference among users  Increased network throughput  Reduce the number of CRs affected by the return of PU  Distributed controlled advantages over centrally controlled  Reduces infrastructure cost  Providing larger flexibility  Providing larger robustness

Page: 9 WMNL  Recently, some MMAC-CRs have been proposed.  Focused on CR performance rather than on protection of the Pus  Not consider missed detections and false alarm  Not consider energy efficiency  Not handled the Hidden PU problem  Require tight synchronization  Focuses on single-hop networks PU A A B B C C Detectability Range

Page: 10 WMNL  Proposes a distributed multichannel MAC protocol for CR networks.  Improve performance  Protect the PUs from interference  Decrease the energy cost  Only requires less tight synchronization  Multi-hop

Page: 11 WMNL Introduction Conclusion Multichannel MAC protocol for CR networks (MMAC-CR) Multichannel MAC protocol for CR networks (MMAC-CR) Performance Evaluation

Page: 12 WMNL  C+1 channels are available for use  None of these channels overlap  One of the channels is a Common Control Channel (CCC)  This channel is free of PU interference  All radios are assumed to have an interface  The interface is capable of dynamically switching their channel  Dedicated for sensing purposes  Communicating and sensing can be done in parallel on different channels

Page: 13 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK DATA ACK Beacon Interval Licensed Channels ATIM-RES RTS CTS

Page: 14 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON Control Channel Beacon Interval Licensed Channels

Page: 15 WMNL E E 00:03 B B F F 00:01 D D 00:02 H H 00:03 C C 00:01 A A 00:02 I I G G 00:01

Page: 16 WMNL E E 00:03 B B F F 00:01 D D 00:02 H H 00:03 C C 00:01 A A 00:02 I I G G 00:01 00:02 00:01

Page: 17 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON Licensed Channels Control Channel Beacon Interval Initialization Update

Page: 18 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON Control Channel Beacon Interval Update Initialization Licensed Channels

Page: 19 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON Control Channel Beacon Interval Initialization Update Licensed Channels

Page: 20 WMNL Spectral Image of Pus (SIP) Channel A B C D E F 0 ： No PU is active 1 ： A PU is active 2 ： The spectral image is uncertain A Ch1 Ch4 B C D F E

Page: 21 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel Beacon Interval Licensed Channels Scan Result Packet

Page: 22 WMNL Spectral Image of Pus (SIP) Channel A Ch1 Ch4 B C D F E A B C D E F [ 0,1,1,1,1,1 ] [ 0,1,1,0,1,1 ] [ 1,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities

Page: 23 WMNL Spectral Image of Pus (SIP) Channel A Ch1 Ch4 B C D F E SRP Time A B C D E F A E F [ 0,1,1,1,1,1 ] [ 0,1,1,0,1,1 ] [ 1,1,1,0,1,1 ] [ 0,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities

Page: 24 WMNL Spectral Image of Pus (SIP) Channel A Ch1 Ch4 B C D F E A B C D E F [ 0,1,1,1,1,1 ] [ 0,1,1,0,1,1 ] [ 1,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities [ 0,1,1,0,1,1 ]

Page: 25 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval Licensed Channels ATIM-RES

Page: 26 WMNL A Ch1 Ch4 B C D F E [ 0,1,1,1,1,1 ] [ 0,1,1,0,1,1 ] [ 1,1,1,0,1,1 ] [ 0,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities Hidden region of C Hidden region of D

Page: 27 WMNL C D [ 0,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities ATIM[0,1,1,0,1,1]ATIM-ACK (Ch2)ATIM-RES (Ch2) A B F E [ 0,1,1,1,1,1 ] [ 1,1,1,0,1,1 ]

Page: 28 WMNL C D [ 0,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities ATIM[0,1,1,0,1,1] Secondary users Channel Load (SCL) Channel A B C D E F ATIM-ACK (Ch2)ATIM-RES (Ch2) A B F E [ 0,1,1,1,1,1 ] [ 1,1,1,0,1,1 ]

Page: 29 WMNL Secondary users Channel Load (SCL) Channel A B C D E F C D [ 0,1,1,0,1,1 ] [ Ch1,Ch2,Ch3,Ch4,Ch5,Ch6 ] Spectral Opportunities ATIM[1,1,1,0,1,1] ATIM-ACK (Ch1)ATIM-RES (Ch1) A B F E [ 0,1,1,1,1,1 ] [ 1,1,1,0,1,1 ] Ch2

Page: 30 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval Licensed Channels ATIM-RES DATA ACK RTS CTS

Page: 31 WMNL Spectral Image of Pus (SIP) Channel A B C D E F 0 ： No PU is active 1 ： A PU is active 2 ： The spectral image is uncertain A Ch1 Ch4 B C D F E

Page: 32 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval Licensed Channels ATIM-RES

Page: 33 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval Licensed Channels ATIM-RES

Page: 34 WMNL Packet Type PriorityBackoff Time ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval ATIM-RES BEACON SRP ATIM ATIM-ACK ATIM-RES Beacon SRP ATIM Handshakes High Low [0, CW / 2) [CW / 2, CW)

Page: 35 WMNL F B G E J CA KI H D L Ch1 Ch2 SRP A I H

Page: 36 WMNL F B G E J CA KI H D L Ch1 Ch2 SRP A I H ,2 Ch2

Page: 37 WMNL F B G E J CA KI H D L Ch1 Ch2 SRP A I H ,2 ATIM-RES (Ch2) ATIM ATIM-ACK (Ch2) K SRP

Page: 38 WMNL F B G E J CA KI H D L Ch1 Ch2 SRP A I H ,2 ATIM-RES (Ch3) ATIM ATIM-ACK (Ch3) K SRP

Page: 39 WMNL ATIM Window (Fast Scan) DATA Window (Fine Scan) BEACON SRP Control Channel ATIM ATIM-ACK Beacon Interval Licensed Channels ATIM-RES DATA ACK RTS CTS

Page: 40 WMNL ATIM WindowDATA Window A ATIM Window B C Time BEACON ATIM ATIM-ACK DATA ACK Doze State ATIM-RES RTS CTS B C A C

Page: 41 WMNL Introduction Conclusion Multichannel MAC protocol for CR networks (MMAC-CR) Multichannel MAC protocol for CR networks (MMAC-CR) Performance Evaluation

Page: 42 WMNL Simulation Parameters Simulatorns-2 (version 2.29) Datarate24Mbps CWmin15 CWmax1023 SIFS 16  s t ATIM 10ms t BI 100ms Fast sensing1ms Fine sensing25ms CRs deploymentRandomly PNs deploymentRandomly

Page: 43 WMNL Power Table of IMEC SDR AnalogDigital  Doze0mW10mW Idle (Fast Sensing) 120mW11mW131mW Receive (Fine Sensing) 120mW370mW490mW Transmit600mW300mW900mW

Page: 44 WMNL Performance metrics Channel Vacate Time Total Interference Time Time and Energy Spent Througuput

Page: 45 WMNL Single-hop Scenario Parameter 4 PNs 20 CRs (10 are communicating) CRs sending 150 packet/s 5 channel 80m  80 m

Page: 46 WMNL Single-hop PU channel statesCR channel states

Page: 47 WMNL Single-hop Channel Vacate TimeTotal Interfered Time

Page: 48 WMNL Single-hop Time and Energy cost

Page: 49 WMNL Single-hop CR Performance

Page: 50 WMNL Multi-hop Scenario Parameter 4 PNs 2 traffic streams (150 packet/s) Interference range 350m 5 channel 500m  500 m

Page: 51 WMNL Multi-hop Channel Vacate TimeTotal Interfered Time

Page: 52 WMNL Introduction Conclusion Multichannel MAC protocol for CR networks (MMAC-CR) Multichannel MAC protocol for CR networks (MMAC-CR) Performance Evaluation

Page: 53 WMNL  Proposes a distributed multichannel MAC protocol for CR networks.  Improve performance  Protect the PUs from interference  Decrease the energy cost  Only requires less tight synchronization  Multi-hop

Page: 54 WMNL

Page: 55 WMNL