S-MAC With Forecast

Wireless sensor network is a multi-hop self-organized network which is formed by lots of cheap sensor nodes arranged on the guard field for information collecting, fusion and transmitting to observers.S-MAC is a medium access control protocol based on competition for wireless sensor network. In S-MAC, energy consumption is greatly reduced by adopting periodic listen and sleep; RTS/CTS can successfully avoid collision that may occur in information transmission, and solve the problem of hidden and explore-station; adaptive listening can shorten communication delay caused by periodic sleep. But in adaptive listening, all the nodes that"hear"the CTS must wake up and keep listening at the end of transmission, which is a waste of energy.To address the problem, a novel MAC protocol--S-MAC with Forecast(S-MAC/F) is proposed in this paper. In this protocol, we add an additional address in the RTS and CTS, so that when a node hear the CTS, it will know who is the next hop after the current communication, and make a decision on whether to wake up or keep a long-time sleep. This rule can reduce energy consumption, improve throughput, shorten the net delay, and avoid collision and overhearing.