Passively Coded Synthetic Aperture Interferometric Radiometer (CSAIR): Theory and Measurement Results

Abstract : —Based on the synthetic interferometric imaging technique (SAIR), a new microwave radiometer architecture is proposed in this paper to detect thermal noise sources with a passive coded measurement approach so called CSAIR. In this new system, a passive microwave device is used to intrinsically code and multiplex the antenna signals. This allows the reduction of the number of RF chains while keeping the same antenna array configuration needed in a conventional interferometric radiometers. The system principle is described and the signal processing required for the target brightness temperature rendering is also discussed. Simulation and measurement results show the effectiveness and the potential of the proposed system.