An Efficient MAC Protocol for MIMO-OFDM Ad hoc Networks

The problem of designing a good MAC protocol for MIMO-OFDM ad hoc networks is considered in this paper. The proposed protocol reserves a portion of the carriers for the control channel. We call this the directional multiple access with collision avoidance (DMACA) protocol. The advantage of DMACA over methods which use the same channel for control and data is that the data channel is collision free. Therefore, the channels are utilized more efficiently. The mathematical models and analysis for both DMACA and the protocol using shared channel are also given. Simulation results show that the mathematical models agree with numerical results. The mathematical model then is used for optimizing the number of carriers reserved for the control channel.