A MAC protocol for mitigating exposed node problem in MIMO ad-hoc networks
<Abstract> This paper proposes a MAC (Medium Access Control) protocol for MIMO ad hoc networks for mitigating exposed node problem. The basic idea of the proposed protocol is applying control gap to SCMA (Stream-Controlled Medium Access). In the proposed protocol, each link can transmit DATA frame simultaneously with fairly assigned stream number by stream control. Additionally, after a transmitter and a receiver succeed a RTS/CTS (Request To Send /Clear To Send) frame handshake, the transmitter and the receiver wait during the control gap. By performing RTS/CTS frame handshake during the control gap, the exposed nodes can transmit DATA frame simultaneously, which resolves the exposed node problem. By applying the control gap to the SCMA, the advantages of the stream control and the control gap are brought out in the proposed protocol, which enhances the network throughput compared with the conventional protocols. Simulation results show the validity and effectiveness of the proposed protocol. |