RADARSAT-2 antenna calibration using Ground Receivers/Transmitters

The RADARSAT-2 antenna is an active phased array of 512 T/R modules. In order to characterize the physical distortions and the amplitude and phase errors across the antenna array, it is planned to perform measurements using the radar in conjunction with a unit on the ground for receiving and recording signals from the satellite, and for generating signals and transmitting them towards the satellite. This unit is referred to as a Ground Receiver/Transmitter. This paper will describe the method of operation of the satellite with the Ground Receiver/Transmitter, the design of the Ground Receiver/Transmitter, and the algorithms to be used to analyze the Ground Receiver/Transmitter data.