实现VB界面下的信号fft变换。界面提供两个波形的卷积，然后对其求FFT变换并显示-VB interface to achieve a signal fft transform. Interface convolution of two waveforms, and then seek its FFT transform and display

数字信号处理的课后编程作业，要求是实现FFT变换，信号的卷积，还有数字滤波器的设计。前两个是VB编写的可执行文件，后面一个是VC的源程序，希望对大家有用 -Digital signal processing of after-school programming operations, the requirements for achieving FFT transform, the convolution signal, as well as digital filter design.

VB实现的FFT，有界面设计，可参考使用-VB of the FFT, interface design, use and reference

Algorithm for researchers to do reference, For time-frequency analysis algorithm, Dual-line interpolation FFT harmonic analysis kaiser windows.