说明：  matlab编写的信号趋势检测，利用信号多项式拟合和时频分析方法用于动态检测信号的异常趋势，给出检测时间，可以关联试验数据进行测试，本程序给出了仿真数据的测试。
(Matlab prepared signal trend detection, use signal polynomial fitting and time frequency analysis method for dynamic detection of abnormal trend of signal, give the detection time, can be associated with the test data for testing, this program gives the simulation data test.)