Wireless Energy Beamforming Using Signal Strength Feedback

TL;DR

This paper presents a simple, efficient method for wireless energy beamforming using RSSI feedback to estimate the channel, validated through numerical and experimental results, applicable across various fading models.

Contribution

Introduces a novel RSSI-based channel estimation scheme for energy beamforming that is simple, general, and easy to implement, requiring minimal processing.

Findings

Achieves high efficiency in wireless energy transfer

Validates the method through numerical and experimental results

Applicable to all well-known fading models

Abstract

Multiple antenna techniques, that allow energy beamforming, have been looked upon as a possible candidate for increasing the efficiency of the transfer process between the energy transmitter (ET) and the energy receiver (ER) in wireless energy transfer. This paper introduces a novel scheme that facilitates energy beamforming by utilizing Received Signal Strength Indicator (RSSI) values to estimate the channel. Firstly, in the training stage, the ET will transmit sequentially using each beamforming vector in a codebook, which is pre-defined using a Cramer-Rao lower bound analysis. The RSSI value corresponding to each beamforming vector is fed back to the ET, and these values are used to estimate the channel through a maximum likelihood analysis. The results that are obtained are remarkably simple, requires minimal processing, and can be easily implemented. Also, the results are general and hold for all well known fading models. The paper also validates the analytical results numerically, as well as experimentally, and it is shown that the proposed method achieves impressive results in wireless energy transfer.