为有效解决时频交叠周期LFMCW信号分离的难题,首先提出一种基于周期AHT(PAHT)的检测算法,通过对匹配函数进行改进,有效积累截获到的交叠多周期能量实现高概率检测,然后将PAHT积累得到的强信号解线调,根据此时的频率分布特性近似量化频率,估计频率量化点与信号频率的偏离差值,再通过频移改善窄带频域滤波分离信号的效果;最后利用IFFT恢复信号,依次循环完成交叠强弱信号的分离。仿真结果对算法的检测效果和复杂度进行了分析,并在验证分离效果的同时采取了两种方法对信号的滤波质量进行了评价,验证了其在低信噪比下的可行性。
To effectively solve the frequency AC stack periods LFMCW signal separation problem, first proposed a detection algorithm based on periodic AHT (PAHT) through improvement of matching function, effective accumulated intercepted the overlapping multi periods energy to achieve high detection probability, then the strong signal PAHT accumulation can be the solution line, at this time frequency distribution characteristics similar to quantify the frequency according to the estimated frequency quantization and signal frequency deviation difference, again through the frequency shift improved narrowband filtering in the frequency domain signal separation effect, finally using IFFT to restore the signal, order cycle complete overlap of strong and weak signal separation. Simulation resuits the detection effect of the algorithm and complexity are analyzed, and verified the results of separation in taken at the same time two kinds of methods of signal filtering quality evaluation, to verify its feasibility at low signal to noise ratio.