1 / 22

A Busy-Tone based MAC Scheme for Wireless Ad Hoc Networks using Directional Antennas

A Busy-Tone based MAC Scheme for Wireless Ad Hoc Networks using Directional Antennas. Hong-Ning Dai, CUHK Kam-Wing Ng, CUHK Min-You Wu, SJTU. GLOBECOM 2007. Outline. Introduction Related work Busy-Tone based Directional MAC (BT-DMAC) Simulation results Conclusion. Introduction.

kylan-gamble
Download Presentation

A Busy-Tone based MAC Scheme for Wireless Ad Hoc Networks using Directional Antennas

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A Busy-Tone based MAC Scheme for Wireless Ad Hoc Networks using Directional Antennas Hong-Ning Dai, CUHK Kam-Wing Ng, CUHK Min-You Wu, SJTU GLOBECOM 2007

  2. Outline • Introduction • Related work • Busy-Tone based Directional MAC (BT-DMAC) • Simulation results • Conclusion

  3. Introduction • Benefit of directional antennas • Transmission range • Reduced interference • Increased spatial reuse

  4. Introduction • Drawback of directional antennas • The hidden terminal problem • The deafness problem

  5. RTS RTS Data Data CTS Hidden Terminal due to unheard RTS/CTS D Collision!! A B C

  6. Introduction (Deafness) A RTS Data B C C does not know node A is busy. C keeps transmitting RTSs to node A

  7. Related Work • Existing MAC protocols using directional antennas • Directional MAC (DMAC) • Dual Busy Tone Multiple Access with Directional Antennas (DBTMA/DA) • Circular-DMAC • Tone-based directional MAC (ToneDMAC)

  8. Motivation and Goal • Motivation • There is no protocol that can completely solve both the hidden terminals and deafness problems with low overhead • Goal • Propose a new MAC protocolto attack the hidden terminal problem and the deafness problem

  9. Antenna Model • Each node equipped with two interfaces: • Directional antenna(Switched beam) • two modes: omni-directional, directional • Data transmission • Omni-directional antenna • only used to send busy tones • notification

  10. Busy Tone • Two omnidirectional busy tones: BTt (the transmitting busy tone) BTr (the receiving busy tone) • BTtand BTris encoded with a beam No. and node ID

  11. Neighbor Discovery (NLT) • A node will record its neighbors’ info when it overhears any frames (RTS,CTS,data and ACK) C Neighbor Location Table (NLT) 3 0 The NLT of Node A A E No 10(ms) 2 1 D B

  12. The Finite State Machine of BT-DMAC

  13. BT ( B , 2 ) BT ( A , 0 ) r t A scenario 3 0 C 2 1 3 0 3 0 D B 2 2 1 1 3 0 3 0 A 2 1 F 2 1 3 0 E 2 1

  14. RTS DATA BT t CTS ACK BT r The time diagram of BT-DMAC A : Data transmission A : Busy tone B : Data transmission B : Busy tone

  15. hidden terminal due to unheard RTS/CTS D B C A

  16. A B DATA C Deafness

  17. Simulation Experiments

  18. Numeric result

  19. Throughput Comparison 1 r= 2 and p = 0.008 ( trts=tcts=tack=5τ, tdata= 100τ)

  20. Throughput Comparison 2 r= 2 and p = 0.008 ( trts=tcts=tack=5τ, tdata= 100τ)

  21. Conclusion • We propose BT-DMAC to attack thehidden terminals and deafness problems. • Simulation experiments prove the effectiveness of our proposed protocol.

  22. Thank you

More Related