高斯白噪声的matlab实现.doc

通信系统建模与仿真实验一、高斯白噪声的matlab实现要求： 样本点：100 1000 标准差：0.2 2 10 均值： 0 0.2白噪声 如果噪声的功率谱密度在所有的频率上均为一常数，即式中：为常数，责成该噪声为白噪声，用表示。高斯白噪声的matlab实现1样本点为1000、均值为0、标准差为0.2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (0.2) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)2样本点为1000、均值为0、标准差为2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (2) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)3样本点为1000、均值为0、标准差为10时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (10) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)4样本点为1000、均值为10、标准差为0.2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (0.2) * randn(1,1) - 10; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)5样本点为1000、均值为10、标准差为2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (2) * randn(1,1) - 10; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)6样本点为1000、均值为10、标准差为10时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:1000; for i = 1:length(f) K = (10) * randn(1,1) - 10; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)7样本点为100、均值为0、标准差为0.2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (0.2) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)8样本点为100、均值为0、标准差为2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (2) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)9.样本点为100、均值为0、标准差为10时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (10) * randn(1,1) - 0; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)10. 样本点为100、均值为10、标准差为0.2时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (0.2) * randn(1,1) - 10; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)11. 样本点为100、均值为10、标准差为10时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (2) * randn(1,1) - 10; P(i) = 10.(K - 3.95*(10-5)*f(i); A(i) = sqrt(2*P(i); endxifft = ifft(A);realx = real(xifft);ti = 1:length(xifft)-1/1000;realx2(1:length(xifft)-1) = realx(2:length(xifft);plot(ti,realx2)12.样本点为100、均值为0、标准差为10时，高斯白噪声分布为下图所示：程序如下所示：% White background nois clear all f = 1:1:100; for i = 1:length(f) K = (10) * ra