Derandomization of Wireless Channel Access using Automata in Sensor Networks

Abstract

Low cost radio transceivers have enabled the deployment of wireless sensor networks (WSNs) using inexpensive and energy constrained nodes. Real time monitoring and control systems using WSNs often seek to maintain a given, but possibly varying spatial and/or temporal, sensing resolution. This control typically consists of both node participation and communication channel access (MAC). This paper proposes integrating both functions into a simple automaton achieving three benefits. First, control of the desired number of transmitting sensors in a given time period is maintained with small variance around the desired mean. Second, channel efficiency (60%) exceeds slotted-ALOHA without explicit synchronization of or idle listening by nodes. Third, the technique implicitly limits the channel load at the maximum supported level with no increase in collisions, and no additional overhead when the desired number of transmitting sensors exceeds the supported capacity