A stochastic model for optimizing physical carrier sensing and spatial reuse in wireless ad hoc networks

The choice of physical carrier sensing (PCS) threshold is key to the trade-off between the amount of spatial reuse and probability of packet collisions in a wireless ad hoc network. In this paper, we present a new analytical approach for optimizing the PCS threshold as measured by probability of packet collisions and the aggregate one-hop throughput. Our model simultaneously incorporates the impact of PCS threshold and the backoff mechanism via a suitable Markov chain model for saturation (i.e. all nodes always have a packet to send in their queues). Elaborate OPNET simulation results show the effectiveness of the analytical model