Satellite communications apparatus using active redundancy

摘要

An active redundancy system (34) for high power satellite communications payloads uses multiple antenna beams driven by multiple power amplifiers (44) and requires power redistribution among the beams during the lifetime of a payload. Instead of commonly used redundancy switches, a number of power amplifiers (44) equal to or greater than the number of antenna feed elements (53) are used to provide extra output power at the beginning of life. As power amplifiers (44) fail, the amplitude and phase of the signals driving the remaining power amplifiers (44) are adjusted to maintain antenna performance. Power amplifiers (44) having sufficient capacity are used to ensure that, given an anticipated number ob power amplifier chain failures, performance requirements can be met at the end of life. <IMAGE>