| Radar means using radio detecting and ranging the target. On the whole, it has two tasks, one is finding the target; the other is measuring the parameters of the target. Frequency Modulated Continuous Wave (FMCW) has been using for a long time. For its main advantages are including small radiant power, high precision, simple apparatus, prone to solidification design, great capability of electronic counter-countermeasures (ECCM) and Low probability of intercept (LPI) performance etc. It is mostly used in measuring range and velocity, such as continuous wave altimeter, range Radar, automotive anti-collision radar etc. Massive research findings have been developed, and a suit of theoretical and technological system has into being referring to FMCW.Based on numerous research works and analyzing for data acquisition system ofLFMCWradar, firstly, this paper expatiates the theory about FMCW range radar, including the calculation of its detecting range and time domain analysis and frequency domain analysis of the mixing signal. After the analysis on theory, the next part of this paper is the design of each component of the Radar Material Level Measuring Instrument, including microwave transceiver and signal processing system.The means of signal processing has a big influence on range precision, so it is important to study the means of signal processing. This paper is mainly about the design of a signal processor that includes hardware and software design such as auto gain control circuit, programmable switched- capacitor high pass filter, frequency measuring circuit, D/A converter. Then simulation and debug are conducted to the whole system, and following that the test result is summed up. The test result and experience gained in operation are highly satisfactory. It confirms the feasibility of the design project.
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