Exploiting smart antennas for spatial reuse and multiplexing in wireless mesh networks

In recent years smart antennas are acknowledged as a prominent PHY layer technology, which can be used for spatial multiplexing, transmit/receive diversity, adaptive beamforming and interference cancellation. In this paper spatial multiplexing and reuse (due to interference cancellation) features of smart antennas are considered to improve the throughput of a wireless mesh network. Two novel link scheduling schemes are presented - strict interference cancellation scheduling (SICS) and flexible interference cancellation scheduling (FISC). SICS applies stream control and enables concurrent transmission of neighboring nodes utilizing their best streams for transmission. In FISC, the transmitter applies all degrees of freedom (DOF) for its data transmission whereas neighboring receivers are facilitated to receive data streams in parallel from the transmitters. Both techniques are simple to apply, no extra delay is induced, and no network information is required. Simulation results show that both techniques outperform the traditional CSMA/CA scheme (exploiting spatial multiplexing).