一种基于24GHz梯形调制LFMCW雷达解多普勒模糊方法

A Doppler Fuzzy Method Based on 24GHz Ladder Modulation LFMCW Radar

由于对称三角线性调频连续波(LFMCW)雷达在多目标情况下容易产生虚假目标,又因为采用的毫米波技术,发射波形的上下扫频时宽相对较小,且目标速度的测量精度和分辨率又取决于信号的时宽,所以,为了消除虚假目标的产生以及提高目标速度的测量精度和准确性,文章利用梯形调制方式,并结合MTD-恒频速度配对法,充分利用二维模糊多普勒频率,通过恒频速度配对得到真实目标之后,再用其求得模糊重数,进而解多普勒模糊。由于二维模糊多普勒频率是在一个周期下得到的,所以,解模糊得到的速度精度要大于恒频速度和上下扫频配对得到的速度。利用这种方法,不仅可以准确地得到目标信息,还防止了虚假目标的产生。最后,经Matlab仿真结果表明,解多普勒模糊得到的速度误差明显小于恒频以及去耦合。

Because of the symmetric triangular linear frequency modulated continuous wave(LFMCW) radar is prone to false targets in multi-target situations,and because of the millimeter wave technology used,the up-and-down sweep width of the transmitted waveform is relatively small,and the target speed is measured accurately. The resolution depends on the time width of the signal. In order to eliminate the generation of false targets and improve the accuracy and accuracy of the target speed measurement,this paper uses the trapezoidal modulation method,combined with the MTD-constant frequency tempo pairing method,fully utilizes the two-dimensional fuzzy Doppler frequency,and obtains the true through the constant frequency tempo pairing. After the target is used,the fuzzy multiplicity is obtained to solve the Doppler blur. Since the two-dimensional fuzzy Doppler frequency is obtained in one cycle,the speed accuracy obtained by defuzzing is greater than that obtained by the constant frequency speed and the up-and-down sweep pairing. Using this method,not only can the target information be accurately obtained,but also the generation of false targets can be prevented. Finally,the simulation results of Matlab show that the velocity error obtained by solving Doppler blur is significantly smaller than constant frequency and decoupling.