可用于测量ADC的信噪比SNR，信纳比SINAD，无杂散动态范围SFDR，总谐波失真THD，得到频谱图及时域图的MATLAB作图,ADC测试方法是fft法(The following program code plots the FFT spectrum of a desired test tone. Test tone based on coherent sampling criteria, and computes SNR, SIN