Design of an RF Power Generator for Directional Radiation in Microwave Power Transfer System

Abstract

This paper presents a kind of radio frequency (RF) power generator with ability of directional radiation in microwave power transfer (MPT) system. This power generator uses quadrature modulation which can regulate amplitude and phase as a close loop. In this paper a novel strategy for directional radiation in the near-field of MPT system is also presented. Operation frequency is 915MHz, output power is 15W and transmission distance is 1m. Directional radiation in MPT system requires phase shifters in order to change the current phases about the elements in antenna array. To compensate the insertion loss of phase shifters, the technique of quadrature modulation is used in this power generator, which maintains the amplitude even though the phase changes. Finally, a prototype is built to verify the theoretical analysis.