自动增益控制仿真程序。为了评估AGC回路的性能，用一系列Matlab仿真实验来证明回路的有效性。首先用数字信号发生器合成一段40KHz的超声波信号，并将其处理成*.dat文件再采集到PC上-Automatic gain control simulation program. In order to assess the performance of AGC loop, using a series of Matlab simulations to prove the validity of lo