1. A Multi-Channel MAC Protocol for Wireless Sensor Networks Chen xun, Han peng, He qiu-sheng, Tu shi-liang, Chen zhang-long The Sixth IEEE International Conference on Computer and Information Technology (CIT'06)

2. Outline Introduction Multi-Channel MAC Protocol Simulation Conclusion

3. Introduction Wireless sensor networks may consist of many different types – Low sampling rate magnetic, thermal, visual, infrared, acoustic and radar The radio bandwidth in WSNs is quite limited – IEEE 802.15.4 standard allows for use of multiple channels available at the physical layer

4. Multi-Channel MAC Protocol Assumption – N channels are available for use – The number of the data channel is N-1 the control channel is one – Each sensor node is equipped with a half-duplex transceiver

5. Multi-Channel MAC Protocol

6. The cluster heads need to negotiate to reserve a Contact-Time for inter-cluster- head communication

7. Multi-Channel MAC Protocol After established the clusters – The cluster head broadcast the synchronous information

8. Multi-Channel MAC Protocol The active period is divided into four stages – Synchronous beacon – Transmission request – Channel schedule and – Data convey respectively

9. Multi-Channel MAC Protocol Synchronous beacon stage – The cluster heads transmit the synchronous beacon signal on the control channel The sensor nodes can adjust their wakeup clocks

10. Multi-Channel MAC Protocol Transmission request stage – The cluster head switches to the listening mode on the control channel – Transmission requested stage is divided into many time slots

11. Multi-Channel MAC Protocol Schedule stage – The cluster head collects all the request information from the member node – The cluster heads distribute channels for the source node and destination node – Broadcast the channel assignment information packets on the control channel

12. Multi-Channel MAC Protocol Data delivery stage – If a node is assigned the channel resource they wakeup to exchange the message on the appointed channel – Otherwise, the node has to keep sleep state throughout the whole data delivery stage

13. Multi-Channel MAC Protocol For broadcast – The cluster head will assign an appropriative channel for source node – The cluster head should piggyback the broadcast packet

14. Simulation

18. Conclusion Proposed a novel multi-channel MAC protocol for wireless sensor network application – Coordinator-based multi-channel MAC protocol – Reduces the network-wide idle

19. Thank you!!