用VB编写的程序，演示出AM调制前后和解调后的波形之间的关系-using VB program, the demo out before and after the AM modulation and demodulation of the relationship between waveforms

利用MATLAB gui 编的短波通信系统，录制一段语音信号，分别通过AM SSB DSB 等调制信号，加入噪声，然后解调出来，可比较各种调制解调方式的优劣。-Use MATLAB gui compiled shortwave communication system, record a voice signal, respectively, by AM SSB DSB modulated signal, etc., added noise, then demodulated, you can