Adaptive control of satellite access powers

An adaptive power control system is one in which the fixed margin (or surplus of power required to cope with periods during which the link suffers from excess attenuation) is small, and additional power is assigned to each link only when required. Results obtained with a real-time digital computer model of a typical communications system indicate that for a system employing a hard limiting transponder, a practical adaptive power balance scheme can save about 3 dB of satellite equivalent isotropically radiated power whilst retaining the same link availability as a fixed transmitter power system. Theoretical work, assuming a perfect scheme, indicates that the maximum saving that can be expected for the same availability is 5 dB.