Study On The Device Controller Unit Of A Space-borne Microwave Radiometer

This thesis introduces the functionality, key technology of designs, and experiment results of the device controller unit of a space-borne microwave radiometer.Microwave radiometer is a high sensitive microwave receiver for detecting of the microwave emission from atmosphere and surface of the earth, which can be used to retrieve the geophysical characteristics. Due to its lower power consumption, lighter in weight, and smaller size, microwave radiometer is a very important tool in earth observation from space.This thesis will focus on the design and test of the device controller unit of a space-borne microwave radiometer with fixed nadir-looking antenna beam. The microwave radiometer consists of a antenna unit, a receiver unit, a temperature sensor unit and a device controller unit. To improve system reliability, all units, except the antenna unit, employ the cold backup.The functionalities of the device controller include sampling the baseband signal from all receiver channels, controlling the operation mode of receiver channels, sampling the temperature results from the temperature sensor, and communicating with the satellite controller. As the central unit of the space-borne microwave radiometer, its reliability and stability are very critical to the normal operation of the device.The whole thesis consists of three parts.The first section introduces the structure of the device controller, and the design consideration of its interface circuits and main components. The block diagram is also provided.For a device on the satellite, the requirements of high reliability and long life cycle, and the inherence of un-maintainable will definitely rely on the quality of the device controller. The second part focuses on the reliability design of the device controller, including the selection of the components, EMC technique, error tolerance design, and anti-irradiation design, etc.The design results of the device controller and the experiment results of the space-borne microwave radiometer are presented in the third part.In a summary, the device controller has been verified along with the space-borne microwave radiometer for more than half year during the system integration in laboratory. The device has worked very well, and the design goals have been completely achieved.