Enable concurrent transmissions with beamforming for broadband wireless access in CSMA/CA-based WLANs

In CSMA/CA based wireless local networks, two stations are not allowed to transmit at the same time due to interference generated to each other, resulting in degraded throughput. Concurrent transmission, which enables simultaneous transmission of two or more stations under certain conditions, is able to overcome this problem, leading to enhanced channel utilization efficiency. Different from earlier work on this topic which focuses on omni-direction concurrent transmission, we introduce in this paper beamforming into a co-channel concurrent transmission scheme and investigate the benefits of concurrency with beamforming. The circumstances for concurrent transmission and frame scheduling are investigated. Simulation results show that the throughput performance achieved by concurrency with beamforming outperforms the traditional transmission and the original omni-directional concurrent transmission.