Abstract: Sleeping is an efficient energy saving approach in wireless sensor networks. Many state of art communication protocols have been designed with periodically sleeping schedule, such as B-MAC, VPCC, X-MAC, A-MAC and so on. In these protocols,broadcast scheme is not proposed or works with large energy consumption and is seriously affected by hidden node problem. An energy efficient broadcasting scheme for the asynchronously sleeping wireless sensor networks was proposed. In this approach, the broadcast data arc retransmitted multiple times with random interval. hhis approach guarantees that the receivers can receive the broadcast data whenever they wake up. When hidden nodes and the broadcast packets are interfering with each other, the random interval can separate the packets earlier. We tested our approach with NS-2 simulation. hhe experiment results show that our broadcast scheme can reduce the energy consumption significantly and reduce the impact of interference.

Key words: Wireless sensor networks, MAC layer, Broadcast protocol