Two-Dimensional Route Switching in Cognitive Radio Networks：A Game-Theoretical Framework

上游充通大 SHANGHAI JIAO TONG UNIVERSITY Two-Dimensional Route Switching in Cognitive Radio Networks: A Game-Theoretical Framework Qingkai Liang,Xinbing Wang,Xiaohua Tian, Fan Wu,Qian Zhang

1 Two-Dimensional Route Switching in Cognitive Radio Networks: A Game-Theoretical Framework Qingkai Liang, Xinbing Wang, Xiaohua Tian, Fan Wu, Qian Zhang

Outline 上游充通大学 SHANGHAI JIAO TONG UNIVERSITY ▣Introduction ▣Network Model Complete-Information Scenario Q Incomplete-Information Scenario ▣Game Analysis ▣Conclusion 2

2 Outline ❑ Introduction ❑ Network Model ❑ Complete-Information Scenario ❑ Incomplete-Information Scenario ❑ Game Analysis ❑ Conclusion

上浒充通大￥ Background SHANGHAI JIAO TONG UNIVERSITY ▣Spectrum Scarcity >Growth of WLAN,Mobile Communications,etc. >Cisco:most mobile data are in unlicensed bands(ISM bands) Unlicensed bands are heavily-utilized Licensed bands are under-utilized Spectrum Utilization of Licensed Bands Heavy Use Heavy Use Sparse Use Medium Use Frequency (MHz) I.F.Akyildiz,W.Lee,M.Vuran,S.Mohanty,"NeXt generation/dynamic spectrum access/cognitive radio wireless networks:A survey",Computer Networks(Elsevier),2127-2159,2006 3

3 Background ❑ Spectrum Scarcity ➢ Growth of WLAN, Mobile Communications, etc. ➢ Cisco: most mobile data are in unlicensed bands (ISM bands) ➢ Unlicensed bands are heavily-utilized ➢ Licensed bands are under-utilized I. F. Akyildiz, W.Lee, M. Vuran, S. Mohanty, "NeXt generation/dynamic spectrum access/cognitive radio wireless networks: A survey", Computer Networks (Elsevier), 2127-2159, 2006. Spectrum Utilization of Licensed Bands

上浒充通大￥ Cognitive Radio Networks (CRN) SHANGHAI JIAO TONG UNIVERSITY ▣Cognitive Radio A promising solution to spectrum shortage Dynamic Spectrum Access Fixed Channel Access Dynamic Channel Access ISM Bands Licensed Bands ISM Bands Licensed Bands idle Unlicensed Users Licensed Users Unlicensed Users Licensed Users Secondary User(SU)Primary User(PU) 4

4 Cognitive Radio Networks (CRN) ❑ Cognitive Radio ➢ A promising solution to spectrum shortage ❑ Dynamic Spectrum Access ISM Bands Licensed Bands Unlicensed Users Licensed Users Fixed Channel Access 1 2 3 ISM Bands Licensed Bands Unlicensed Users Licensed Users idle Dynamic Channel Access 1 2 3 Secondary User (SU) Primary User (PU)

上洋充通大学 Cognitive Radio Networks (CRN) SHANGHAI JIAO TONG UNIVERSITY ▣Spectrum Mobility >High-priority PUs can reclaim their licensed channels at any time. >SUs must cease their transmission on the licensed channels. >Spectrum availability is dynamic(or mobile)to secondary users. Time 1 Time 2 idle idle SU PU PU 5

5 Cognitive Radio Networks (CRN) ❑ Spectrum Mobility ➢ High-priority PUs can reclaim their licensed channels at any time. ➢ SUs must cease their transmission on the licensed channels. ➢ Spectrum availability is dynamic (or mobile) to secondary users. SU PU 1 2 3 idle Time 2 SU PU 1 2 3 Time 1 idle

上浒充通大 Route Switching SHANGHAI JIAO TONG UNIVERSITY ▣ Spectrum Mobility Route Break Route Switching Potential Location for Building Bridges Bridge (correspond to a physical data link) (Correspond to a Licensed Channel) Source Destination Re-select a new spatial route(switch to a new spatial route)? Routing Costs Build a new bridge at the same location?(switch to a new channel)?Channe/Switching Costs 6

6 Route Switching ❑ Spectrum Mobility Route Break Route Switching Source Destination Build a new bridge at the same location? (switch to a new channel) ? Re-select a new spatial route (switch to a new spatial route) ? Channel Switching Costs Routing Costs Potential Location for Building Bridges (correspond to a physical data link) Bridge (Correspond to a Licensed Channel)

上浒充通大学 Route Switching SHANGHAI JIAO TONG UNIVERSITY In order to balance routing and switching costs,joint switching in both Spatial and Frequency domains is necessary! Two-Dimensional Route Switching 7

7 Route Switching In order to balance routing and switching costs, joint switching in both Spatial and Frequency domains is necessary! Two-Dimensional Route Switching

上浒充通大￥ Route Switching SHANGHAI JIAO TONG UNIVERSITY Two-Dimensional Route Switching 0 0 E Channel 1 2 1 2 Channel 2 Channel 2 Channel 5 B Channel 5 B D 2 1 2 1 Channel 4 Channel 3 Channel 4 Channel 3 (a)original route and channel assignment (b)channel 1 is reclaimed by PUs 0 0 E E Switch to Channel 6 2 Ch)e1 1 1 Channel 2 B B D Channel 2 Channel 5 Channel5 2 1 2 1 Channel 4 Channel 3 Channel 4 Channel 3 (c)strategy update when switching costs are 1 (d)strategy update when switching costs are 3 8

8 Route Switching ❑ Two-Dimensional Route Switching

8 上洋充通大学 Overview of Results SHANGHAI JIAO TONG UNIVERSITY Route Switching Existence of the potential function in CRN Existence of the Nash Equilibrium(NE) Complete Information An algorithm for finding the NE Game Model A low-complexity algorithm for finding the approximate NE Existence of Bayesian Nash Equilibria(BNE) Incomplete Information A simple algorithm for finding the BNE Price of Anarchy Be upper-bounded Game Analysis Bayesian Price of Anarchy Be deterministically bounded 9

9 Overview of Results Comp Complete lete Information Incomplete Information Existence of the potential function Existence of the Nash Equilibrium (NE) An algorithm for finding the NE A low-complexity algorithm for finding the approximate NE Existence of Bayesian Nash Equilibria (BNE) A simple algorithm for finding the BNE Game Analysis Be upper-bounded Be deterministically bounded Improvement Price of Anarchy Bayesian Price of Anarchy Game Model Route Switching in CRN

Outline 上浒充通大￥ SHANGHAI JIAO TONG UNIVERSITY ▣Introduction ▣Network Model >Network Architecture >Flow Interference Model >Cost Model Complete-Information Scenario Q Incomplete-Information Scenario ▣Game Analysis ▣Conclusion 10

10 Outline ❑ Introduction ❑ Network Model ➢ Network Architecture ➢ Flow & Interference Model ➢ Cost Model ❑ Complete-Information Scenario ❑ Incomplete-Information Scenario ❑ Game Analysis ❑ Conclusion