Environmental considerations for the microwave beam from a solar power satellite

Solar power satellite (SPS) systems in geosynchronous orbit are possible future energy sources. The SPS concept uses a highly focused microwave beam to transmit the energy to the earth. The microwave power transmission system parameters are summarized, emphasizing those parameters which may affect the earth's environment. Environmental impacts of the microwave beam are discussed. The power levels for the main beam, sidelobes, grating lobes, and ground receiving antenna reradiation patterns are presented. Ionospheric/microwave beam interaction studies, experimental and theoretical, are reviewed. Possible radio frequency interference sources and the magnitude of expected interference levels are discussed.