用周期循环检测算法检测频谱： 首先运行a.m程序，通过此程序运算得出循环频率a值； 再运行zhouqi.m程序，对a值进行确定，通过周期循环算法对信号进行检测； -Cycle detection algorithm to detect: First run the am program cycle frequency a value obtained through this program operations Then run zhouqi.m program to