| Doppler Velocity Measurement System is based on the Doppler effect, which is widely applied on science and project. Its main task is to measure the Doppler frequency which is proportional to the speed of moving objects. The thesis mainly focuses on the digital signal processing technique of Doppler Velocity Measurement System. It orients to ordinary moving objects and can be used to construct many practical application system.Be aimed at Doppler Velocity Measurement System, we design an appropriate digital signal processing circuit, which includes carrier generator, beat signal processing and Doppler frequency measuring. As the kernel of Doppler Velocity Measurement System, Doppler frequency measuring is very important. In the thesis, a complete synchronization digital frequency meter is designed, which has effectively eliminated the positive and negative 1 error. We analyzed a series of noise and optimized the whole digital system. Besides, on the part of data transmission, a transmitter named UART which is asynchronous and serial is designed. As a result, no extra communication circuit is needed, so that the board design is simplified.The testing results of our Doppler Velocity Measurement System showed quite decent performance. For typical motor rotational speed of 10m/s, our measurement showed 9.944m/s, which had only an error of 0.5% compared to real case. In addition, a series of samples have been tested within the designated bandwidth. The measurement results match the real speed quite well.
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