Interference dynamics in MANETs with a random direction node mobility model

Interference is one of key factors of performance degradation in wireless communications. Various interference models have been proposed in the literature. However, most of them did not take node mobility into account. In fact, as an interferer approaches a carrier sensing range due to node mobility, the transmitted frame may also encounter a collision. Due to the interfering source, it is necessary to make an effective interference model to characterize the interference and signal-to-interference ratio(SIR). In this paper, we propose a novel interference model through interference and SIR distribution functions obtained from mobile nodes. In particular, we focus on a random direction (RD) model. Based on the probability distribution function of distance between any node pairs, we theoretically estimate the distribution of the accumulated interference contributed by concurrent transmissions and the corresponding SIR values. Through this result, we investigate the probability of successful transmissions and the probability of carrier sensing failures.