Synthetic Aperture Imaging Microwave Radiometer Inversion Algorithm And Experimental Study

As a passive remote sensor, microwave radiometer will be used widely in remote sensing application. The applied fields of conventional microwave radiometer are limited because of the low spatial resolution. Synthetic aperture technology in radio astronomy is introduced into microwave radiometer since 1980抯, the configuration of antenna system is thinned effectively and the spatial resolution is improved using interferometry. The basic theory of aperture synthesis used in microwave radiometer is analyzed systematically in this paper, theoretical analysis of aperture synthesis and baseline design are presented in both cross track and along track directions, respectively. The results of numerical simulations and experiments show that the theory of aperture synthesis is feasible. Because the precision of Fourier transform retrieval algorithm is poor, two numerical retrieval algorithms, the method of moment and the linear algorithm based on Backus-Gilbert theory, are applied. The precision of retrieval is improved efficiently under these two algorithms. The theoretical analysis and baseline design of two-dimensional imaging radiometer based on aperture synthesis are presented, the results of numerical simulation show that these designs are feasible.