Understanding and Improving the Spatial Reuse in Multi-hop Wireless Networks

1. Understanding and Improving the Spatial Reuse in Multi-hop Wireless Networks Tae-Suk Kim, Hyuk Lim, and Jennifer C. Hou. The Department of Computer Science, University of Illinois, Urbana-Champaign IEEE Transactions on Mobile Computing, Vol. 7, No. 10, October 2008

2. Outline • Introduction • Network Model and Analysis • Power and Rate Control Algorithm • Simulation Study • Conclusions

3. Introduction • In Multi-hop Wireless Networks • Collision problem • 4 way-handshake • Physical carrier sensing range • Spatial reuse • Power control • Lower data rate Tradeoff between Collision and Spatial reuse

4. Goal • Propose a distributed algorithm • Power control  Spatial reuse • Rate adaption  Higher data rate

5. Interference Model and Analysis

6. Network Capacity Model and Analysis carrier sensing in an area

7. Power and Rate Control AlgorithmStep 1 • Determine the power range • TX0 : Pmin TX(1,2,3,4,5,6) : Pmax >

8. Algorithm – Step 2 • Determine the carrier sense threshold

9. Algorithm – Step 2 • The interference level perceived at TX

10. Simulation Study : (NS2 v2.28) • Algorithm: PRC, Static, DSB, and Greedy Power Control • Scenario : Random and Grid

11. Simulation Results : Random Topology

12. Simulation Results : Rrid Topology

13. Conclusions • The relation of two control knods in the PHY/MAC layer • Transmission power • Carrier sense threshold • Proposed a localized PRC algorithm • Higher data rate  Ptx/Tcs • Spatial Reuse  Efficient power control scheme

14. Thank You.