A random backoff algorithm for wireless sensor networks

Medium Access Control (MAC) protocols employ a backoff algorithm to resolve contention among nodes to acquire channel access. It is desirable to design the backoff algorithm so that the node with lots of remaining energy has a high probability to win in channel contention since the network lifetime can be prolonged by balancing energy consumption over the wireless sensor network. However, most MAC protocols designed for wireless sensor networks have fixed contention period regardless of residual energy, which gives every node the same opportunity to win in the competition. In this paper, we propose a backoff algorithm for wireless MAC which uses dynamic contention period based on the amount of residual energy at each node. Simulation results show that our scheme achieves more power saving and a longer lifetime comparing with the conventional backoff algorithms.