Collision probability estimation in wireless networks

Wireless Networks are vulnerable to collisions and interferences from other radiation sources due to the broadcast nature of wireless channels. Collisions may occur when two or more stations sharing the physical medium transmit simultaneously. Contention-based protocols for medium access control (MAC) aim at reducing collisions in these networks. However, the presence of hidden terminals can still cause high levels of collision, specially as their number and the network load grow. Estimating collision probability in wireless links may support routing protocols, rate adaptation algorithms, and other mechanisms. This paper presents a novel mechanism to estimate packet collision probability in wireless networks caused by the presence of hidden terminals. The proposed method is based on information regarding medium usage, which can be exchanged between two-hop neighbors. In order to evaluate the proposal, simulations were conducted comparing it to two other models found in the literature. Results demonstrate improvements in collision probability estimation, albeit the model may still be refined to take into account important parameters.