Distributed Decode and Forward Beamforming

Distributed transmit beamforming is a wireless communication technique in which multiple independent antennas transmit a common message while controlling their transmitted carrier phases to constructively interfere the message at a destination. Depending on the transmission goals and choice of network parameters, certain noteworthy benefits arise from beamforming. These benefits may include improved received signal to noise ratios, increased transmission ranges, power consumption reductions, or physical layer security against eavesdropping. We present a distributed cross-layer cooperative beamforming protocol implemented into the IEEE 802.11 wireless communication stack: Distributed Decode and Forward Beamforming. In this paper we conduct a brief literature review of current beamforming research, and present a detailed discussion on the mathematical foundation of the single- and multi-destination decode and forward beamforming technique. We then describe our distributed multi-destination decode and forward beamforming protocol, and present results from our in-depth evaluation of our protocol in a realistic simulation environment. In our evaluation, we investigate five aspects of our distributed beamforming protocol: beamforming event frequency, queue length, latency, participation level, and throughput.