| Along with development of general-purpose parallel DSP technique at very fast speed, newer and stronger processing modules are provided to develop higher performance radar systems. Combined with improvement of processing method, requirement of faster and larger operation capacity for new generation radars can be satisfied.This dissertation focuses on the key techniques such as pulse compression and moving target indication etc, adopted widely by modern radars. And it mainly studies the realization method in frequency domain for digital pulse compression technique. A multi-waveform pulse compression system in frequency domain is successfully exploited, which is applicable to complete pulse compression real-time processing of linear frequency modulation, nonlinear frequency modulation waveform and phase coded signals. The designed bandwidth of signal reaches 5MHz, sampling rate reaches 6.6MHz and time-width is under 42us. The experimental results demonstrate that the specification characteristics of this system meet the requirements of practical radars and it can be applied to various radars.The content of the dissertation are arranged as follows. In chapter one, the development of radars and correlative techniques are summarized and author's prime work is introduced. Chapter two illustrates the basic radar signal processing theories that are closely related to work in this dissertation and some key corollaries are concluded. In chapter three, computer simulations of multi-waveform pulse compression processing in frequency domain are completed. And for LFM signal, a new type of combined-window function weighting is proposed, which synthetically considers main specification characteristics. Chapter four analyses summarily clutter simulation and general moving target indication technique. A Method of noncoherent moving target indication suited to wideband radar clutter suppression is pointed out. Chapter five introduces in detail currently up to date general-purpose DSP and parallel processing technique, and points out design idea based on general-purpose DSP parallel processing module and software method. Chapter six mainly expatiates on design and testing of the multi-waveform pulse compression general-purpose parallel processing system in frequency domain, and corresponding experimental results are given.The main creative work in this dissertation includes:(1) The characteristics of various pulse compression signals whose bandwidth is 5MHz and TB ≤ 210 is comprehensively investigated in frequencydomain. Based on 6.6MHz sampling rate used by practical radar systems, through computer simulations for differ Doppler offsets, the important research results suited in actual application, are gained.(2) In previous researches, classical weighting window functions and spectra modification are adopted to suppress side lobe. In this dissertation, a new type of combined-window function weighting for LFM pulse compression is proposed. It synthetically considers multiple specification characteristics such as RMS, width of main- lobe and SNR loss etc. It can be effectively applied for practical radar systems.(3) NMTI method suited to WB/UWB radar systems is pointed out, which is used to detect moving target through instantaneous displacement of radar echo signals. It not only can completely avoid affect of "blind speed" and simplifies system design, but also can effectively detect targets of different speed including low speed.(4) Aiming at requirements of large operation capacity, modularization, apt-replant and real time processing, design idea and developmental direction to use general-purpose parallel processing modules for high speed radar signal processing system, is proposed to simplify design and to shorten the period of time used to develop.(5) Based on general-purpose parallel module-HHPC made up of currently popular ADSP-21160 SHARC DSP, and through correlative arithmetic research, a digital pulse compression system in frequency domain is successfully developed. Practical system test...
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