GSMAC: Group-Scheduled MAC Protocol with Energy Beamforming in M2M Networks

Abstract

In Machine-to-Machine (M2M) networks, an enormous number of stations with low energy budgets contend for the channel access in order to get the transmission opportunity, leading to huge amount of congestion. Energy beamforming technology enables wireless devices to replenish their energy much faster than the traditional energy harvesting strategies. In this paper, a group-scheduled Medium Access Control (GSMAC) protocol is proposed as a solution of managing the access of stations that transmit bursts of data packets while taking into account the benefit of energy beamforming technology in M2M networks. In the proposed protocol, nodes are grouped by multiple Power Beacons in order to reduce the high collision probability. Nodes first contend the channel access in each group for reservation opportunities so that the reserved nodes can transmit data and harvest energy simultaneously by Access Point scheduling the data and energy transfer order. Simulation and analytical results show that GSMAC has significant improvements compared with the traditional distributed coordination function in terms of saturation throughput, delay, and energy-related performances.