A unified framework for performance evaluation of multi-hop ad hoc networks

The performance of multi-hop CSMA/CA networks has in most cases been evaluated via simulations, or analytically using a perfect collision channel model. Using such methods, one can neither have access to the capture nature of the terminals nor evaluate the performance of the network in a fading environment. In this paper a new analytical framework that takes into account these capture and fading effects is presented. The network investigated in this paper has an infinite number of nodes which is assumed to be spatially Poisson distributed. The approach is to develop analytical expressions for the transition probabilities in a Markov chain model of the network. A fast algorithm to solve these equations is also given. Numerical results show that the model agrees with simulation results for both omni-directional networks and networks employing beamforming. The framework can easily be extended and implemented for networks with different access protocols, routing strategies, and forward error correcting mechanisms. Therefore, it provides a useful tool for cross-layer network design.