The microwave power transmission system would be very similar to that proposed for the solar power satellite. That is, a circular phased array antenna with slotted waveguide radiators and either magnetrons or klystrons for DC-RF power conversion would be used. Antenna/rectenna sizing tradeoffs as a function of transmission efficiencies, taper analyses, and resulting field patterns are discussed. Grating lobe intensities and main beam degradations as a function of antenna tilt are also given. Several alternate microwave system configurations are recommended for further studies. ORBITAL CONSIDERATIONS The nuclear satellite must maintain a relatively constant distance from the space station for both tethered and untethered configurations. Previous analyses have shown that close formation, free (untethered) flying for a space station and a subsatellite is not feasible due to the large propellant requirements for subsatellite orbital maintenance (1). Figure 1 shows possible locations for a tethered nuclear satellite: Positions 1 and 2 have the advantage of being gravity-gradient stabilized; positions 3 and 4 would require differential drag to maintain the station/sateilite orientation. For microwave power transmission, position 1 incurs the disadvantage of sidelobe radiation incident upon the Earth; position 2 produces the disadvantage of sidelobe radiation upon Earth-viewing space station windows.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==