RM-MAC: A routing-enhanced multi-channel MAC protocol in duty-cycle sensor networks

Multi-channel media access control (MAC) is important in wireless sensor networks because it allows parallel data transmissions and resists external wireless interference. Existing multi-channel MAC protocols, however, do not efficiently support delay-sensitive applications that require reliable and timely data transmissions. In addition, multi-channel operation is inherently deficient for supporting multi-hop broadcasting, due to independent waking-up schedules on sensors. To address these issues, we present a routing-enhanced multi-channel MAC (RM-MAC) which allows nodes to coordinately select their channel polling times based on cross-layer routing information. RMMAC also supports a ripple broadcast mechanism which achieves efficient multi-hop broadcast among sensors. Simulation results show that RM-MAC provides significant improvement over the MuCHMAC [1], in terms of end-to-end delay, under a wide range of traffic loads including both unicast and broadcast traffic.