| The development trend of modern radar is multifunction, high resolution, ultra broad-band, etc. Ultra-wideband radar is a new type of radar system，which has unique advantagesof high range resolution, good anti-jamming performance, anti-stealth technology, lowprobability of interception, etc., so it is with the potential of wide applications. UWB radarsignal has very wide bandwidth, which affects the range of the signal; this paper adopts thepulse compression technology to solve this contradiction. Because of UWB radar signalwith very wide bandwidth, the existing A/D converter cannot sample the UWB radar signaldirectly, so this paper uses multichannel integrated system for pulse compression signal.First, UWB radar signals cannot be directly sampled; band-splitting technology is usedfor data collection, two methods from the time domain and frequency domain is researchedand analyzed. In the time domain commonly analog filter is analyzed qualitatively theappropriate filter is selected quantitatively, and the influence of various parameters on theband split is acquired. How to compensate the distortion of the band split signal istheoretically analyzed. And the band split principles in the frequency domain and the timedomain is compared, and the signal simulation is implemented.Secondly, each channel signal after band splitting reduces the requirement of A/Dconverters, and can be directly sampled. Then the calculation of each sub band signal isreduced for pulse compression processing. Side lobe increases after pulse compression, soin this paper a window function is adopted for side lobe suppression. As conventionalwindow function can suppress the side lobe but it broaden the bandwidth. The windowfunction combined with convolution is put forward, and the feasibility of this technology isverified through the simulation analysis. Not only the side lobe is suppressed, but also thedegree of main lobe spreading is reduced.Finally, the sub band signal is interpolated before integrated multi-channel for differentsampling rate. Sinc interpolation function is adopted, and the sampling rate of sub band isadvanced by interpolation, so that the sampling interval is equal to the interval of pulsecompression. Through the composition of multi-channel synthesizer, the UWB signal resultof pulse compression is got. By matlab simulation, the number of sub band, the windowfunction, and the impact of interpolation function is discussed and analyzed of the system toverify the feasibility of the proposed method. Then simulated on the hardware platform to prove the correctness of integrated multi-channel pulse system. |
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