E-CSMA: Supporting Enhanced CSMA Performance in Experimental Sensor Networks Using Per-Neighbor Transmission Probability Thresholds

A transmitter in a wireless network that uses CSMA, a simple carrier sensing-based MAC protocol, to determine the likelihood of successful packet reception at the intended receiver can easily be misled. At the same time, CSMA variants and hybrid MAC protocols based at least in part on carrier sensing have become the de facto standard in wireless sensor networks, underscoring a need to improve its performance. We propose to enhance the de facto state of carrier sensing-based MACs in wireless sensor networks by using low cost channel feedback combined with a learning approach to try to better predict the probability of a successful reception, on a per-receiver basis. We show results from an experimental wireless sensor network testbed, where our proposal E-CSMA (Enhanced CSMA) provides up to a 55% improvement in network performance.