% QAMModem.m程序清单
% 仿真4比特原始数据与星座图的编码映射过程；
% 完成16QAM信号的调制解调；
% 基带信号符号速率 ps ＝1Mbps；
% 成形滤波器的滚降因子 a=0.8；
% 载波信号频率fc=2MHz ；
% 采样频率 Fs=8MHz ；
% 绘制16QAM信号的频谱及时域波形；
% 采用相干解调法仿真其解调过程；
% 绘制解调前后的基带信号时域波形；
% 将原始基带数据、QAM已调数据、滤波器系数写入相应的文本文件中。
clc;(%Qammodem. M program list

%The coding mapping process of 4-bit original data and constellation is simulated;

%Complete the modulation and demodulation of 16QAM signal;

%Baseband signal symbol rate PS = 1Mbps;

%Roll off factor of shaping filter a = 0.8;

%Carrier signal frequency fc = 2MHz;

%Sampling frequency FS = 8MHz;

%Draw the spectrum and time domain waveform of 16QAM signal;

%The coherent demodulation method is used to simulate the demodulation process;

%Time domain waveform of baseband signal before and after demodulation is drawn;

%Write the original baseband data, QAM adjusted data and filter coefficient into the corresponding text file.)