Scalable, High-Sensitivity X-Band Rectenna Array for the Demonstration of Space-to-Earth Power Beaming

This paper presents a large, modular X-band rectenna array developed for the planned demonstration of a space-to-Earth power beaming link operating at 10 GHz. The array is composed of 16 tiles assembled into a panel greater than 1 m x 1 m in size. To accommodate tests during the early development and construction of the space-based transmitter, the rectenna cells are designed to maximize performance at low power densities using commercial-off-the-shelf Schottky diodes. To increase efficiency at the expense of some field-of-view, each rectenna cell employs a 4-antenna subarray to feed a single diode. Array performance is validated over a 30-dB range of power densities from 1 mW/m
²
to 1 W/m
²
, reaching a total rectenna efficiency in excess of 39% at 1 W/m
²
. The rectenna array's field of view, defined by the 3-dB beamwidth of its antenna subarray, is 36° ×36°. The DC power collected by each tile is combined in a reconfigurable manner to control the output voltage level for the protection of electrical loads. These results are expected to directly influence the first demonstrations of space-to-Earth power transfer.