Performance of IEEE 802.11 medium access control protocol over a wireless local area network with distributed radio bridges

In this paper, the throughput and access delay performance of a distributed wireless local area network employing the IEEE 802.11 medium access control protocol is analyzed by computer simulations. The proposed network uses the same radio channel over the entire coverage area for wireless terminals to communicate with multiple radio bridges (RBs) with macrodiversity. A channel model with additive white Gaussian noise, log-normal shadowing and Rayleigh fading is considered, with or without capture effect at each receiver. Without capture effect the throughput of a linear network with 4 RBs is improved by at least 120% over that with one RB. With capture effect, the increase in performance with number of RBs is reduced as the capture ratio is increased. A two dimensional network model is also considered and found to have slightly different performance.