A novel one-bit feedback collaborative beamforming algorithm using two time slots

Collaborative beamforming is an effective approach when transmitting common message to a relatively distant destination. In collaborative beamforming, it is necessary to compensate the unknown phase offset for the phase alignment at the receiver. We introduce a new method for the one-bit feedback collaborative beamforming scheme to achieve the phase alignment. The receiver feeds back one bit at each time slot, but the transmitters exploit two successive feedback bits, including the current and last feedback bits, to make decision. The algorithm can adjust the step of random perturbation and the size of directional factor accordingly. The results show that less time slots are required to achieve the phase alignment and the convergence speed is improved greatly.