I am trying to create brown noise by integration of white noise (random walk).
I created Gaussian white noise. The histogram shows Gaussian distribution and Welch (and also FFT) shows flat spectrum.
Now I try to integrate it
$x(k+1) = x(k) + q(k)$
where $q$ stands for white noise and $x$ for resulting Brownian noise.
According Wikipedia I would expect that there should be straight line in the plot.
What I am doing wrong?