Implementing adaptive power control as a 30/20-GHz fade countermeasure

Satellite systems in the 30/20-GHz band are very susceptible to outages due to rain-induced fades. In order to reduce the impact of these fades, it has been proposed that the power of a transmitting ground station be adjusted during the fade to compensate for the additional attenuation. Real-time frequency scaling of attenuation from the downlink to the uplink shows promise for estimating the uplink attenuation for uplink power control (ULPC). A scaling-type ULPC algorithm using 20-GHz attenuation scaled to 30 GHz is presented. The limitations of such an algorithm and the effects of scintillation on ULPC are explored. The algorithm is tested using OLYMPUS fade data measured on the 14/spl deg/ elevation OLYMPUS to Blacksburg, VA path. An ULPC scheme employing a beacon at the uplink is also presented. It offers better performance than scaled downlink attenuation ULPC.