Synthetic Aperture Microwave Radiometer Analog Multiplier And Its Peripheral Circuit

The microwave radiometer occupies on the important status in themicrowave remote sensing instruments,it is used widely ,such as remotesensing ,guidence,target characteristic detect and so on . At thebeginning of 1980s, the synthetic aperture concept is introduced tothe remote sensing and used to observe the earth. Its basic conceptis that measure in the spatial frequency domain instead of measurein the spatial domain with the traditional radiometer. It applies twoelement interferometers that are different in the length andorientation of the baseline to sample in the spatial frequency domain,and retrieve the image by Inverse algorithm . Because the cellantenna of the interferometers can be used many times by differentbaselines,and its radius is very small,so the large antenna in physicsaperture can be dispersed into cell antenna array. And with theelectrical scanning instead of the mechanical scanning ,so it iseasy to be launched and carried In space.this thesis introduces the principles and system structure ofsynthetic aperture radiometer. In theory, analog multiplier andsurrounding circuits including a four order Butter-worth low passfilter based on Multisim software is designed. Performance of thecircuits is consistent with the simulations. Furthermore, errorsintroduced by correlator are analyed. The whole circuits are debuggedand the results are in accord with demand.