这个是通信系统与仿真作业，题目：已知输入信号为x(t)=sin(2*pi*50t)+0.5sin(2*pi*150t ),增量调制器的采样间隔为1ms，量化阶距delta=0.4，单位延迟器初始值为0。试用数据流和时间流两种方法建立仿真模型并求出前20个采样点时刻上的编码输出序列以及解码样值波形。

-This is a communication system simulation operation, Title: known input signal x (t) = sin (2* pi* 50t)+0.5sin (2* pi* 150t), delta modulator sampling interval of 1ms, quantitative order from the delta = 0.4, the unit delay is the initial value of 0. Trial data flow and the flow of time are two ways to establish the simulation model and find moments before 20 sampling points on the output sequence encoding and decoding sample waveform.