A Study of Dependence of DC Output of Rectenna Array on the Method of Inter-connection of Its Array Element

Abstract

In 1994 and 1995, a ground-to-ground microwave power transmission (MPT) experiment was carried out by a group of Kyoto University, Kobe University and Kansai Electric Power Company. Among the MPT technologies, which are one of the most important key issues for the realization of the Solar Power Satellite (SPS), studies of “rectenna” (rectifying antenna) have been pursued to archive higher efficiency of conversion from microwave to DC. We had developed a new rectenna panel which can effectively rectify a microwave power of 2.5W at 2.45GHz before the ground-to ground MPT field experiment.
We examine the sum of the outputs of two or three rectenna panels in which are connected ether in parallel or in series or in the hybrid connection under the same microwave circumstances. The experiment leads us to conclude: (1) The sum of the DC outputs from two rectenna panels connected in parallel is larger than that from those connected in series. (2) The sum of the DC outputs of two rectenna panels is generally smaller than the sum of the DC output of the individual panels unless their output is equal to each other. (3) The total output DC power of a rectenna array increases when we connect the array element with consideration of the “element balance”. Based on the experiment, we propose an optimum method for connection of individual rectenna elements to form an rectenna array.