Performance of hybrid link power control using wideband gapfiller satellite-based automatic level control (ALC) and ground-based link power control (LPC)

The wideband gapfiller satellite (WGS) is planned for launch in 2005, Features include the use of phased array antennas to form eight shapeable beams in X band; and mechanically-steered dish antennas to form ten beams in Ka band. Automatic level control (ALC) for each channel may optionally be used to maintain total channel power at the ALC output at a constant level. Digital signal processing techniques are used to implement switchable and gain-adjustable 2.6 MHz subchannels. This paper examines the use of ALC on the WGS satellite; and considers interactions between the ALC (which has variable gain) and link power control (LPC), when both are employed. Simultaneous use of ALC and LPC, when suitably configured, results in a more efficient utilization of the WGS system.