DSB-SC信号的生成与解调 1) 用离散（DSP）的方法生成DSB信号 2) 载波频率为150KHz，音频为500Hz和2000Hz的混合音。 3) 加入高斯白噪声 （4） 语音信号 的传输。 改变抽样频率和量化台阶大小，观察重建信号以及量化噪声信号的波形；对于语音信号主观评价声音质量的变化。 -DSB-SC signal generation and demodulation 1) Discrete (DSP) methods to generate DSB signal 2) the carrier frequency to 150KHz, audio 500Hz and 2000Hz for the mixed tone. 3) by adding white Gaussian noise (4) transmission of voice signals. Change the sampling frequency and quantization step size, to observe the reconstruction of signal and quantization noise signal waveform for subjective evaluation of the speech signal changes in sound quality.