摘要 |
Electrical power at microwave frequencies produced by solar cells or similar devices on satellite stations in space is phase modulated prior to its being beamed to earth. At the receiving station on earth, the power in the beamed signal is recovered at the modulation frequency. In the first embodiment, the microwave signal from the power originating device drives a circularly polarized antenna; the modulation is achieved by reversing the phase of the drive signals so that the polarization of the propagated wave alternates between right hand and left hand polarization at a 360 Hertz rate. On earth, the detected outputs of the receiving antennas are combined in such a manner to produce a 60 Hertz three phase power signal. In the second embodiment, the microwave signal drives two orthogonal, linearly polarized antennas; the modulation is achieved by gradually changing the phase of the microwave drive signals so that the polarization of the propagated wave rotates at a 60 Hertz rate. On earth, the detected outputs of three linear antennas, spaced at 120 DEG angular intervals, are summed to produce a 60 Hertz three phase power signal.
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