A Simple Phase Adaptation Algorithm for Compact Microwave Power Transmitter Array

In this paper, a simple phase adaptation algorithm that can reduce the system complexity of the microwave power transmitter (Tx) array is proposed. The proposed algorithm finds the optimal transmission phase through the variation of the received power according to the change in the power transmission phase. In order to compare the proposed algorithm to the conventional retroreflective method used in many recent microwave power transmission (MPT) systems, a massive Tx array operating in the 5.2 GHz band was implemented. Using the implemented system, power transfer experiments were conducted using both methods. No difference was found for the received power levels using both methods. Number of measurements, which is required to reach the optimum transmission phases for the maximum received power, is presented according to the number of array elements using the proposed algorithm.