Ground-based beamforming for satellite communications systems

A method for ground-based beamforming (GBBF) of a communications satellite payload, said method comprising:

• receiving via a feeder link, (i) a plurality of return path signals traveling from user terminals via the communications satellite payload to at least one gateway, and (ii) a plurality of forward path signals traveling from the at least one gateway via the communications satellite payload to the user terminals;
• measuring a first set of amplitude and phase errors of the plurality of return path signals;
• correcting said first set of amplitude and phase errors by generating, on the ground, a first set of corrective beam forming coefficients and applying said first set of corrective beam forming coefficients to the return path signals;
• measuring a second set of amplitude and phase errors of the plurality of forward path signals;
• and
• correcting said second set of amplitude and phase errors by generating, on the ground, a second set of corrective beam forming coefficients and applying said second set of corrective beam forming coefficients to the forward path signals.

A satellite, said satellite comprising:

• a satellite communications payload communicatively coupled to a gateway via a feeder link, and to a plurality of user terminals via a user link, said satellite communications payload comprising a satellite return path and a satellite forward path,
• said satellite configured to operate within a satellite communications network having a ground-based beamforming (GBBF) system wherein the GBBF system:
• receives, via the feeder link, (i) a plurality of return path signals traveling from the user terminals via the satellite to the at least one gateway, and (ii) a plurality of forward path signals traveling from the at least one gateway via the satellite to the user terminals;
• measures a first set of amplitude and phase errors of the plurality of return path signals;
• corrects said first set of amplitude and phase errors by generating, on the ground, a first set of corrective beam forming coefficients and applying said first set of corrective beam forming coefficients to the return path signals;
• measures a second set of amplitude and phase errors of the plurality of forward path signals;
• and
• corrects said second set of amplitude and phase errors by generating, on the ground, a second set of corrective beam forming coefficients and applying said second set of corrective beam forming coefficients to the forward path signals.

A gateway, said gateway communicatively coupled to a satellite via a feeder link, and configured to operate within a satellite communications network comprising the satellite, the gateway, and a plurality of user terminals, said satellite communications network having a ground-based beamforming (GBBF) system wherein the GBBF system:

• receives, via the feeder link, (i) a plurality of return path signals traveling from the user terminals via the satellite to the at least one gateway, and (ii) a plurality of forward path signals traveling from the at least one gateway via the satellite to the user terminals;
• measures a first set of amplitude and phase errors of the plurality of return path signals;
• corrects said first set of amplitude and phase errors by generating, on the ground, a first set of corrective beam forming coefficients and applying said first set of corrective beam forming coefficients to the return path signals;
• measures a second set of amplitude and phase errors of the plurality of forward path signals;
• and
• corrects said second set of amplitude and phase errors by generating, on the ground, a second set of corrective beam forming coefficients and applying said second set of corrective beam forming coefficients to the forward path signals.