2013级硕士研究生数字通信MatLab仿真实验题
姓名 学号 1. 请采用MatLab分别对工作于AWGN信道的PAM、PSK和QAM信号的传输错误概率性能进
行仿真,并与理论结果进行比较。
1) 对于PAM信号传输在AWGN信道上的Matlab仿真
a. simulink仿真图
RandomIntegerRandom IntegerGeneratorM-PAMM-PAMModulatorBasebandAWGNAWGNChannelTx Error Rate CalculationRxError RateCalculationScopeM-PAMM-PAMDemodulatorBaseband 图1: simulink PAM信号AWGN信道仿真图
b. 2PAM 和4PAM 星座图
图2: 2PAM 星座图
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图3: 4PAM 星座图
2) 对于PSK信号传输在AWGN信道上的Matlab仿真
a.simulink仿真图
RandomIntegerRandom IntegerGeneratorM-PSKM-PSKModulatorBasebandAWGNAWGNChannelTx Error Rate CalculationRxError RateCalculationScopeM-PSKM-PSKDemodulatorBaseband 图4:simulink PSK信号AWGN信道仿真图
b. 4PSK 和16PSK星座图
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图5: 4PSK 星座图
图6: 16PSK 星座图
3) 对于QAM信号传输在AWGN信道上的Matlab仿真
a.simulink 仿真图
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RandomIntegerRandom IntegerGeneratorRectangularQAMRectangular QAMModulatorBasebandAWGNAWGNChannelTx Error Rate CalculationRxError RateCalculationScopeRectangularQAMRectangular QAMDemodulatorBaseband 图7:simulink QAM信号AWGN信道仿真图
b. 16QAM 和32QAM星座图
图8: 16QAM 星座图
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图9: 32QAM 星座图
4.理论值测量
按照《数字通信》编写程序
%Analysis of the symbol error probablility for M-PAM, M-PSK,M-QAM %finished by JS clc;clear;
Eb_N0 = logspace(0.5,2); %rang of Eb/N0: 5-20dB M = [2 4 8];
MPAM = zeros(3,50); MQAM = zeros(3,50);
%MPAM;MQAM BER calculation
êculate PM which is used in the QAM EBR calculation %PM = 2*(1-1/sqrt(M(i)))*erfc(sqrt(3*EB_N0/(M-1))); %1= evaluation of symbol error probability for i = 1:3
%the BER formula of MPAM
MPAM(i,:)= 2*(1-1/M(i))*erfc(sqrt(Eb_N0 * 6 * log2(M(i))/(M(i)^2-1))); %the BER formula of MQAM
PM = 2*(1-1/sqrt(M(i)))*erfc(sqrt(3*Eb_N0/(M(i)-1))); MQAM(i,:)= 1.-(1.-PM).^2; end
subplot(1,3,1);
semilogy(10*log10(Eb_N0),MPAM(1,:),'.',10*log10(Eb_N0),MPAM(2,:),'*',10*log10(Eb_N0),MPAM(3,:),'o'); title('MPAM');
axis([-6 20 1e-6 1e-1]); subplot(1,3,2);
axis([5 20 1e-6 1e-1]);
semilogy(10*log10(Eb_N0),MQAM(1,:),'r-',10*log10(Eb_N0),MQAM(2,:),'g-',
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