A reliable CSMA protocol for high performance broadcast communications in a WSN

Wireless Sensor Networks have been identified as a promising technology to efficiently perform distributed monitoring, tracking and control tasks. In order to accomplish them, since fast decisions are generally required, high values of throughput must be obtained. Additionally, a high packet reception rate is important to avoid wasting energy due to unsuccessful transmissions. These communication requirements are more easily satisfied by exploiting the broadcast nature of the wireless medium, which allows several simultaneous receptions through a unique node transmission. We propose a Medium Access Control protocol that ensures, simultaneously, high values of throughput and a high packet reception rate in broadcast scenarios. To this extent, we first propose a utility function to measure the performance of the network in terms of these two parameters. Then, we design a medium access policy that, relying on local and adaptive decisions of the nodes, obtains greater values of this utility function than existing approaches based on fixed communication thresholds.