Impact of transmit power on throughput performance in wireless ad hoc networks with variable rate control

In this paper, the capacity of ad hoc networks employing pure aloha MAC protocol is studied under the effect of different transmission power levels and variable data rate control. The data rate of a certain link is related to SINR, and SINR is, in turn, related to transmitted power and link distance. The increasing of power conducts a high data rate, while results in a high interference of the network. Consequently, the optimum power that yields maximum network throughput is a tradeoff between transmission rate and network interference. Mathematical models for analysis of ad hoc networks capacity is presented, and a revised expression to approximate the capture probability of the network is also proposed. It is demonstrated that the optimal transmission power, thus the optimal range, which maximize the throughput of the network by theoretical and simulation results.