Performance Analysis based Markov Chain in Random Access Heterogeneous MIMO Networks

Abstract In heterogeneous MIMO wireless LANs (WLANs), a multi-dimensional carrier sense multiple access (MDCSMA) based MAC protocols is developed by researchers to support multiple independent APs to communicate with its clients on the same channel, taking advantage of the extra degrees of freedom provided by nodes with more antennas. In this paper, we present an analytical model based on Markov chain to characterize the performance in throughput and mean access delay of this MDCSMA protocol in heterogeneous MIMO network. In MDCSMA protocol, nodes with more antennas than contention winner can allowed to continue to carry out carrier sense but in a space orthogonal to the ongoing transmissions. In each dimension carrier sense, we adopt p-persistent CSMA scheme to contend for the medium and dynamically adjust the average backoff time of p-persistent according to the number of nodes participated in and the available duration of average data transmission.Simulation and analysis results show that the analytical model can give close prediction of the network throughput of the multi-dimension carrier sense MAC protocol.