The Design Of Scattering Measuring System And Experiment

Having the characteristic of good penetrability and not limited by weather conditionsand time, microwave remote sensing is one of the most effective techniques for earth’sremote sensing, lunar exploration and deep space exploration. It include active microwaveremote sensing and passive microwave remote sensing. And microwave scatterometer is aequipment for active microwave remote sensing.On the basis of expounding the basic theory of scattering measurement, fundamentalconstitute and calibration method of scatterometer, this dissertation designs a set ofmicrowave scattering measuring system in accordance with ground-based simulationexperimental requirements of lunar surface exploration. The hardware includes T/Rchannel and calibration subsystem and data acquisition subsystem.In software aspect, a set of high speed data acquisition program used for acquisitionand processing of echo signals is designed based on Labview. The program not onlyrealizes the function of data acquisition, waveform display, spectrum display and pulsecompression wave display, but also has accurate synchronization and a friendly systeminterface and can be expanded easily.The set of microwave scattering measuring system could be used for microwavescattering measurement. Besides, the system could be used as an ordinary radar to studyradar imaging algorithm.The proposed system was used for measurement experiment in order to test thefunction. During the experiment, linear frequency modulation (LFM) signal was used asthe radar transmit signal, and different bandwidth and pulse width were set for comparison,pulse compression techniques and inversion algorithm were used for azimuth resolutionduring the later data processing. The experimental results show that the higher power ofemission signal is, the higher detecting capacity is, and the range resolution improves asbandwidth increases, but the resolution will decline when pulse width increases.Meanwhile, the experimental results also demonstrate the rationality of the systemdesigning.