Opportunistic Beamforming with Wireless Powered 1-bit Feedback Through Rectenna Array

TL;DR

This paper proposes an opportunistic beamforming scheme where terminals powered by wireless energy provide 1-bit feedback via rectenna arrays, with analytical derivation of beam outage probability for different rectenna configurations.

Contribution

It introduces a novel OBF scheme with wireless-powered 1-bit feedback and derives closed-form outage probability expressions for two rectenna topologies.

Findings

Closed-form beam outage probability for direct-current combiner.

Closed-form beam outage probability for radio-frequency combiner.

Analytical insights into the impact of rectenna topology on beamforming performance.

Abstract

This letter deals with the opportunistic beamforming (OBF) scheme for multi-antenna downlink with spatial randomness. In contrast to conventional OBF, the terminals return only 1-bit feedback, which is powered by wireless power transfer through a rectenna array. We study two fundamental topologies for the combination of the rectenna elements; the direct-current combiner and the radio-frequency combiner. The beam outage probability is derived in closed form for both combination schemes, by using high order statistics and stochastic geometry.