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Multi-hop communications in directional CSMA/CA over mmWave WPANs

In this paper, we consider the multi-hop communications in contention period of medium access control protocol over millimeter-wave band. A relaying devices selection policy and a grouping algorithm are proposed, and the directional carrier sense multiple access/collision avoidance protocol in the immediate acknowledgement mode for IEEE 802.15.3c is considered under saturation environments. The purpose of this paper is to analyze the effect of using directional antennas and relaying devices in contention period. A sensing region and an exclusive region are computed probabilistically and used in the grouping algorithm. Numerical results show that the narrower radiation beamwidth allows to use a channel more spatially, and the effect of using relaying devices increases as the beamwidth and number of devices increase. Those effects are presented in the throughput and average delay. The obtained results will be used as performance criterion for the multi-hop communications in millimeter-wave wireless personal area networks. Copyright © 2015 John Wiley & Sons, Ltd.