Passive corner reflectors are used to find the system transfer functions relating the amplitudes of a SAR image to ° values and to derive receiver and transmitter characteristics of a multichannel polarimetric SAR from the complex image data. Results are presented from the 1989 airborne SAR calibration campaign at DLR test site Oberpfaffenhofen. The sensors available were the DLR E-SAR operating in C-Band/VV mode and the NASA/JPL multifrequency multipolarization DC-8 SAR.