Reduction of local oscillator spurious radiation from phased array transmit antennas

摘要

The present invention is a system and method for reducing the transmission of spurious radiation produced by local oscillators (LOs) in a spacecraft-based phased array antenna. The spurious radiation is reduced by spreading a substantial portion of the radiation outside of the earth disk. The spurious LO leakage radiation is spread by adjusting the phase of the LO signal to a specific value in each elemental path such as shifting the phase of the LO signal in every other elemental path by 180 degrees. The phase shifting of the LO signal can be accomplished by various methods, such as the insertion of a transmission line having a length of &lgr;/2 in the LO signal path prior to entering a mixer in every other elemental path, where &lgr; is the wavelength of the LO signal.