System for conducting video communications over satellite communication link with aircraft having physically compact, effectively conformal, phased array antenna

Abstract

A system architecture and communication methodology for significantly reducing the size of an aircraft antenna required to provide full broadcast quality video communications with an aircraft via a satellite communications link includes a combination of video bandwidth compression, spread spectrum waveform processing and an electronically steered, circular aperture phased array antenna, that is conformal with an airframe surface of the aircraft. The combination provides sufficient signal power to the aircraft, enables interference from other satellites to be rejected and maintains the power spectral density of the satellite's video transmission within FCC requirements. The polarization of the receive array is aligned with that of the incoming beam from the relay satellite by means of an error signal feed back path to control the steering weights of the array. Because the phased arrays are conformal, it is necessary to modify the phase shift settings produced by the antenna steering mechanism executed by the degree of departure of the conformal geometry of the array from a planar configuration. A coordinate transformation look-up table is coupled in the control feedback path from the antenna steering mechanism and the phase shift elements of the phased array.