A carrier sense multiple access protocol with power backoff (CSMA/PB)

In this paper we propose an alternate approach to collision resolution in a CSMA protocol. Most contention protocols resolve collisions by backing off in time. We introduce spatial backoff, the use of power control to resolve collisions by backing off in space. We call this approach power backoff (PB) and incorporate it into a CSMA protocol as CSMA/PB. Through simulation, we show that collision resolution using power backoff can be remarkably successful, outperforming IEEE 802.11 in both static and mobile ad hoc network scenarios. CSMA/PB improves end-to-end throughput and uses less energy; overall gains in throughput per unit energy are substantial.