标签: awgn白高斯噪声
2013-10-29 18:30
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awgn
将白色高斯噪声添加到信号中
语法
y = awgn(x,snr)
y = awgn(x,snr,sigpower)
y = awgn(x,snr,'measured')
y = awgn(x,snr,sigpower,state)
y = awgn(x,snr,'measured',state)
y = awgn(...,powertype)
描述
y = awgn(x,snr)将白高斯噪声添加到向量信号x中。标量snr指定了每一个采样点信号与噪声的比率,单位为dB。如果x是复数的,awgn将会添加复数噪声。这个语法假设x的能量是0dBW。
y = awgn(x,snr,sigpower)和上面的语法相同,除了sigpower是x的能量,单位为dBW。
y = awgn(x,snr,'measured')和y = awgn(x,snr)是相同的,除了agwn在添加噪声之前测量了x的能量。
y = awgn(x,snr,sigpower,state)和y = awgn(x,snr,sigpower)是相同的,除了awgn首先重置了正态随机数产生器randn的状态为整数状态。
y = awgn(x,snr,'measured',state)和y = awgn(x,snr,'measured')是相同的,除了awgn首先重置了正态随机数产生器randn的状态为整数状态。
y = awgn(...,powertype)和前面的语法相同,除了字符串powertype指定了snr和sigpower的单位。powertype的选择有'db' and 'linear',如果powertype是'db',那么snr是按照dB为单位测量的,sigpower是按照dBW为单位测量的。如果powertype是线性的,snr是按照一个比率测量的,sigpower是以瓦特为单位测量的。Relationship Among SNR, Es/N0, and Eb/N0
对于SNR和其他的噪声相对能量测量的关系,查看Describing the Noise Level of an AWGN Channel。
例子
The commands below add white Gaussian noise to a sawtooth signal. It then plots the original and noisy signals.
t = 0:.1:10;
x = sawtooth(t); % Create sawtooth signal.
y = awgn(x,10,'measured'); % Add white Gaussian noise.
plot(t,x,t,y) % Plot both signals.
legend('Original signal','Signal with AWGN');
Several other examples that illustrate the use of awgn are in Getting Started. The following demos also use awgn: basicsimdemo, vitsimdemo, and scattereyedemo.
See Also
wgn, randn, bsc, AWGN Channel