MICROWAVE-POWER TRANSMISSION USING TAPERED BEAMS

The safety and efficiency of microwave power transmission from solar p ower satellites (SPS's) is constrained by the existence of beam sidelo bes. These sidelobes contain power that is wasted, and that may be haz ardous to surrounding populations. The amount of power in the sidelobe s can be minimized by varying the intensity of the beam across the fac e of the transmitting antenna, a process known as beam tapering. A fam ily of beam tapers is examined, and recommendations are made on the ba sis of tradeoffs involving maximizing the amount of power in the main lobe, minimizing the peak beam intensity at both the transmitting ante nna and the rectifying antenna (rectenna), and minimizing both the rec tenna size and the size of the exclusion zones (unsafe areas) around t he rectennas. The effects of frequency scaling is discussed, and sever al different microwave safety standards are considered.