A multiplicative weight perturbation scheme for distributed beamforming in wireless relay networks with 1-bit feedback

This paper focuses on perturbation-based distributed beamforming with 1-bit feedback for wireless amplify-and-forward relay networks. We propose to use multiplicative perturbations based on Givens rotations to adapt the beamforming weights while guaranteeing a sum power constraint for the relays. This perturbation scheme is shown to be computationally efficient and easy to design, thus allowing for low-complexity relay nodes. An adaptation of the Givens rotation angle allows to approach optimum performance arbitrarily close. Numerical simulations demonstrate noticeable performance gains over additive perturbation schemes that have been exclusively considered up to now.