.5 Mm Fm Detection System Research And Implementation Of Signal Processing

Combine the good privacy, strong interference immunity of the millimeter-wave in the non-atmospheric window with the wide large plot, no blind spots of the FM radar system, 5mm FM ranging system has a wide range of applications in the short-range detection. In theory, the ranging accuracy of FM ranging system depends on the sweep bandwidth, but increasing the sweep bandwidth is difficult to achieve. In addition, non-linear of the FM will cause the increase of the spectral side lobe thus inundate the target, impairing the ranging accuracy. In the project, the stability of the VCO's frequency is not fine, linearity is also not ideal. Therefore, people always improve the ranging accuracy through finding better methods to measure frequency."Beat-FFT" is usually used in the millimeter wave short-range FM detection system to estimate the distance of target, but the picket fence effect (PFE) of the FFT make the range accuracy greatly reduced. ZFFT, some extent, improves the range accuracy by partial frequency spectrum refinement. In projects, Sample date limited, refinement multiple restricted, the PFE also exited, the estimation is not ideal in this case. So, ZFFT Window Spectrum Fitting Algorithm is put forward.Based on the relevant research results of signal processing about millimeter wave FM ranging system and combined with the demand of actual project, this paper involves the theory and realization of the realization of the 5mm system, this work contains the project design, the research of signal processing arithmetic, the development of hardware, the software realization of arithmetic and the debugging of system. The main research work and results can be summarized as follows:1. Accomplishing the project design of a 5mm FM ranging system;2. Completing the design and simulator of the signal processing arithmetic. Based on the ranging error analysis, put forward a improved arithmetic -- ZFFT Window Spectrum Fitting Algorithm, and combined with actual experiment data, presents the results.3. Accomplishing the design and realization of the hardware about the signal processing system. Using the DSP board as platform, combined with the FM system requirements, design the SCH chart and PCB chart then send them to the factory, complete arithmetic of the signal processing system radar with C language.4. Using the develop hardware board above as the platform, Accomplished the debugging and testing between the hardware and the software and the whole signal processing system.The results indicate that the signal processing system is effective and coincident with the system's demand. The experimental test date also illustrated the algorithm and the system is feasible.