CSR: Cooperative Source Routing Using Virtual MISO in Wireless Ad hoc Networks

1. CSR: Cooperative Source Routing Using Virtual MISO in Wireless Ad hoc Networks Yang Guan, Yao Xiao, Chien-Chung Shen and Leonard Cimini Speaker: Wun-Cheng Li • IEEE WCNC 2011

2. Outline • Introduction • Goal • Cooperative Source Routing (CSR) • Building SISO Network Topology • Cooperative RREQ Transmission • Selecting Relay Nodes to Forward RREQs • Feedbacking RREP to Source • Transmitting Data Packets • Performance evaluation • Conclusion

3. Introduction • To improve the spectrum efficiency and link reliability of wireless communications • space-time communications • Simultaneously transmitted at the source and received at the destination by multi-antennaarrays • improve the performance

4. Introduction • Multiple-input single-output (MISO) systems on a single node can improve signal quality • Limited physical size • Cost constraints TX RX

5. Introduction • Cooperative Transmissions • Virtual antenna array • Improve signal quality • Enhance the performance of both throughput and energy-efficiency TX RX TX RX TX RX

6. Introduction • Compared to the single-input single-output (SISO) link • Virtual MISO link can achieve diversity gain • Reflect into a decrease in the reception threshold at the receiver

7. Related Work DSR • Dynamic Source Routing (DSR) • route request (RREQ) B RREQ:S RREQ:S, A A S RREQ:S, A,C RREQ:S, A,C RREQ:S, A RREQ:S, A D C

8. Related Work DSR • Dynamic Source Routing (DSR) • route request (RREQ) • route reply (RREP) B RREP:D,C,A RREP:D RREP:D,C A S D C

9. Related Work DSR • Dynamic Source Routing (DSR) • route request (RREQ) • route reply (RREP) • Then specific nodes along the primary routeare selected to establish VMISO links.

10. Problem • The quality of VMISO links highly depends on the primary SISO route discovered.

11. Goal • The cooperative gains can be utilized to improve network performance • lower end-to-end delay • higher route discovery success ratio

12. Cooperative Source Routing (CSR) • Building SISO Network Topology • The neighbor update messages build up a SISO network topology (SNT) • Periodically broadcasts a neighbor update message D B A C

13. Cooperative Source Routing (CSR) • Cooperative RREQ Transmission T O R D D B A B F S M E K Q C C L P J pilot tones local RREQ Cooperative RREQ Transmission

14. Cooperative Source Routing (CSR) • Selecting Relay Nodes to Forward RREQs d is a candidate node’s SISO hop count to the destination is set to be the total time for a RREQ to traverse from a source to a destination with 20 cooperative RREQ forwarding steps r is a random variable between 0 and1 C is the maximum time to transmit one cooperativeRREQ is set to be 8 to avoid extra energy consumption

15. Cooperative Source Routing (CSR) • Selecting Relay Nodes to Forward RREQs T O R D B A F S M E Q K C L P J

16. Cooperative Source Routing (CSR) • FeedbackingRREP to Source T O R D B A F S M E Q K C L P J ?

17. Cooperative Source Routing (CSR) • FeedbackingRREP to Source T O R D B A F S M E Q K C L P J

18. Cooperative Source Routing (CSR) • Transmitting Data Packets T O R D D A B B F S M M E K Q K C C L L P J J Data Data

19. Cooperative Source Routing (CSR) • Transmitting Data Packets • receive an acknowledgement havecertain time threshold T T O R D B A F S S M M E K Q K C L L P J J ACK ACK

20. Performance evaluation • QualNet 3.7 Controlled network topology

21. Performance evaluation

22. Performance evaluation

23. Performance evaluation

24. Conclusions • This paper proposed cooperative source routing (CSR) protocol to better exploits the cooperative gain facilitated. • Simulations results show that CSR facilitates higher route discovery success ratio and low end-to-end delay.

25. Thank you!