Cross layer design for broadband ad hoc network with MIMO-OFDM

Multiple input multiple output (MIMO) and orthogonal frequency division multiplexing (OFDM) are very promising techniques for broadband wireless communication. However, these promising techniques have not been realized in ad hoc networks. In this paper, we propose transceiver architecture with MIMO-OFDM and medium access control (MAC) scheme for broadband ad hoc networks. In our scheme, each node has multiple antennas and the independent data flows from different nodes are made into virtual MIMO OFDM scheme. At each transmit node, space-time coding (STC) is used among multiple antennas to improve the reliability of the communication between nodes to nodes. Data flows from independent nodes can be separated using detection algorithms in receiver nodes. For this transceiver architecture, a new cross layer design MAC scheme-multiple antennas receiver initiated busy tone medium access (MARI-BTMA) is proposed based on receiver initiated busy tone medium access (RI-BTMA). MARI-BTMA uses multiple out of band busy-tones to notify the nodes about the number of users in the system to avoid the collision of the nodes on the same channel. Analysis and simulation results show the improved performance of MARI-BTMA compared with RI-BTMA and carrier sensing medium access/collision avoidance (CSMA/CA).