TDRSS ANTENNAS GROUND STATION AND SPACEBORNE

Abstract

Three sixty foot diameter Ku-Band Antennas have been completed as part of the Tracking and Data Relay Satellite System (TDRSS) at the NASA Johnson Space Center, White Sands Test Facility. These very high efficiency satellite communication antennas provide in excess of 68dBi directivity. Further characteristics include autotrack accuracy of 0.01E, frequency reuse, and surface accuracy within less than .02" rms of the desired shaped surface. Two TDRSS antennas weighing less than 52 pounds are ready for launch aboard each satellite. These 16 foot deployable antennas provide frequency reuse performance in two frequency bands - Ku and S. As with the sixty foot antenna, shaping of the subreflector and main reflector is utilized to achieve high aperture efficiency. This paper describes some of the design, analysis and measurement techniques used in the development of these antennas.