Analysis of an Improved Temperature Management Concept for SAR System Calibration Transponders

Kurzfassung

For the radiometric calibration of spaceborne synthetic aperture radar systems, active targets with known backscatter, so called transponders, are used. These serve as an external absolute reference, and the quality of the derived calibration parameters depends on the quality of the deployed transponders. Due to the temperature dependent behavior of the implemented active radio frequency components the transponder radar cross section is sensitive to the temperature of the components. This effect requires the implementation of a reliable and precise temperature management System to stabilize the temperature of the radio frequency components to a constant value under all relevant environmental conditions. In order to fulfill the increasing requirements for future transponders towards radiometric accuracy new temperature control concepts must be developed. For this purpose, existing temperature management systems are analyzed and a promising concept is investigated. In the final version of this paper the results of measurements in a climatic chamber are presented in order to analyze the performance of the new control concept.