The Sun as a Calibration Signal Source for L- and S-Band Telemetry

摘要

A far field signal source is needed for frequent calibration of telemetry receiving stations in the L- and S-bands to insure proper station performance at all times. The sun provides sufficient signal strength in these bands, and its subtended angle of 0.5 deg from the earth is small enough to permit the calibration of the majority of telemetry stations. Solar observatories around the world are continuously measuring solar flux with an estimated error of less than 7 percent. If L- and S-band solar flux measurements were made available to telemetry stations through an essentially real time communications link the sun could be used as a signal source for calibration purposes. Characteristics of solar emission are reviewed briefly, and the methods of determining receiving system noise temperature are developed. (Author)