>> which awgn
D:\Program\matlab2006a\R2006a\toolbox\comm\comm\awgn.m
>> help awgn
AWGN Add white Gaussian noise to a signal.
Y = AWGN(X,SNR) adds white Gaussian noise to X. The SNR is in dB.
The power of X is assumed to be 0 dBW. If X is complex, then
AWGN adds complex noise.
Y = AWGN(X,SNR,SIGPOWER) when SIGPOWER is numeric, it represents
the signal power in dBW. When SIGPOWER is 'measured', AWGN measures
the signal power before adding noise.
Y = AWGN(X,SNR,SIGPOWER,STATE) resets the state of RANDN to STATE.
Y = AWGN(..., POWERTYPE) specifies the units of SNR and SIGPOWER.
POWERTYPE can be 'db' or 'linear'. If POWERTYPE is 'db', then SNR
is measured in dB and SIGPOWER is measured in dBW. If POWERTYPE is
'linear', then SNR is measured as a ratio and SIGPOWER is measured
in Watts.
Example: To specify the power of X to be 0 dBW and add noise to produce
an SNR of 10dB, use:
X = sqrt(2)*sin(0:pi/8:6*pi);
Y = AWGN(X,10,0);
Example: To specify the power of X to be 0 dBW, set RANDN to the 1234th
state and add noise to produce an SNR of 10dB, use:
X = sqrt(2)*sin(0:pi/8:6*pi);
Y = AWGN(X,10,0,1234);
Example: To specify the power of X to be 3 Watts and add noise to
produce a linear SNR of 4, use:
X = sqrt(2)*sin(0:pi/8:6*pi);
Y = AWGN(X,4,3,'linear');
Example: To cause AWGN to measure the power of X, set RANDN to the
1234th state and add noise to produce a linear SNR of 4, use:
X = sqrt(2)*sin(0:pi/8:6*pi);
Y = AWGN(X,4,'measured',1234,'linear');
See also wgn, randn, and bsc.
Reference page in Help browser
doc awgn |