Abstract: A method and apparatus for producing contiguous spot beam communications coverage on the Earth's surface are disclosed. The apparatus comprises two contiguous beam patterns. The first contiguous beam pattern comprises a first set of cells and has a first set of frequencies. The second contiguous beam pattern comprises a second set of cells and has a second set of frequencies. The second contiguous beam pattern is spatially offset from the first contiguous beam pattern such that an edge of the first set of cells is offset from an edge of the second set of cells. Multiple two grid systems can maintain isolation performance of single grid system.

Abstract: The present invention discloses methods and an apparatus for characterizing an antenna system. The apparatus comprises a processor, a coupler, and a converter. The processor selectively injects a test signal into amplifiers in the antenna system while other amplifiers are amplifying the broadcast signal, and the amplified signals are then fed to a hybrid matrix. The coupler samples the combined amplified test and broadcast signals, and the converter converts the combined test and broadcast signals to a different frequency band to separate the test signal from the broadcast signal. The processor determines a phase response and an amplitude of the first amplifier and a phase effect of the hybrid matrix by measuring the separated test signal and modifies a phase of the broadcast signal using the determined phase response of the first amplifier and the hybrid matrix when the broadcast signal is subsequently provided to the first amplifier.

Abstract: The present invention discloses methods and an apparatus for characterizing an antenna system. The apparatus comprises a processor, a coupler, and a converter. The processor selectively injects a test signal into amplifiers in the antenna system while other amplifiers are amplifying the broadcast signal, and the amplified signals are then fed to a hybrid matrix. The coupler samples the combined amplified test and broadcast signals, and the converter converts the combined test and broadcast signals to a different frequency band to separate the test signal from the broadcast signal. The processor determines a phase response and an amplitude of the first amplifier and a phase effect of the hybrid matrix by measuring the separated test signal and modifies a phase of the broadcast signal using the determined phase response of the first amplifier and the hybrid matrix when the broadcast signal is subsequently provided to the first amplifier.