An Error Calibration Method Based on Prior Information for Aperture Synthesis Radiometers

The errors of aperture synthesis microwave radiometers （ASMRs） have great influence on the performance of the system,and should be calibrated. However, it＇s difficult to calibrate the errors of ASMRs with large aperture and high working frequency. An error calibration method based on prior information for ASMRs is presented in this paper, which con- sists of a calibration matrix based on prior information and a CLEAN algorithm based on prior information. Firstly, the imper- fect system response, as the prior information, is used to construct the calibration matrix, and a primary image can be recon- structed. Then, the array factor of ASMRs estimated from the prior information is introduced to the CLEAN algorithm and used to calibrate the remained errors in the primary image. Simulation and experiment results show the error calibration meth- od can greatly improve the image quality of ASMRs. All the errors can be calibrated in image reconstruction by the calibration method, and the performance requirement of calibration hardware system is reduced. So this error calibration method is suit- able for the error calibration of large millimeter wave aperture synthesis radiometers.