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## Signal-correlated additive white Gaussian noise
## Kyle Gorman <kgorman@ling.upenn.edu>
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## Usage: 
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## newsig = scawgn(x, snr);
##

function y = scawgn(x, snr)
    noise = randn(size(x)); % gaussian noise
    y = ((1 + snr ^ 4) ^ (-.5)) * (x + (snr ^ 2) * (noise .* x));
endfunction