A 6-Element Helical Retrodirective Array for High Power Wireless Power Transmission

In this paper we provide the test results of a 6-element, high power, phased array antenna used for radiative wireless power transmission. A retrodirective approach is used to target the power transmission in a desired direction. The frequency used for the power transmission is 2.496GHz which lies in the 2.4-2.5GHz ISM frequency band. We used a 6 element array of helical antennas to transmit the electromagnetic power. Retrodirective operation was practically validated for the 6 element array with total transmit power of 60W (10W per element) at up to 84% drain efficiency at the transmit power amplifiers. The tests have been carried out in the Queen’s University Belfast anechoic chamber at the Centre of Wireless Innovation (CWI).