用Matlab产生一个频率为1Hz、功率为1的余弦信源，设载波频率为10Hz，并画出：

1.DSB调制信号及其功率谱密度；

2.将已调信号解调，在时域内将解调后的波形与原信号进行对比；

3.A=2的AM调制信号及其功率谱密度；

4.SSB调制信号及其功率谱密度；

5.在信道中各自加入经过带通滤波器后的窄带高斯白噪声，功率为0.1，解调各个信号，并画出解调后的波形。

-Matlab produce a frequency for 1 hz, power for 1 cosine source, a carrier frequency for 10 hz and draw the:

1. The DSB modulation signal and power spectral density

2. Will be modulated signal demodulation, in the time domain waveform and the demodulation of the original signal are compared

3. A = 2 AM modulation signal and power spectral density

4. SSB modulation signal and power spectral density

5. In the channel of each join after bandpass filter after the narrow band gaussian white noise, power is 0.1, each signal demodulation, and draw the demodulation of waveform.