From Class Wiki
GNU Radio + GNU Radio Companion
- GNU Radio Companion is installed with GNU Radio 3.2 and above. Install from the trunk. Synaptic Package Manager will only install 3.0.4
- GNU Radio Companion is the GUI for GNU Radio
Installing GNU Radio + GNU Radio Companion
- Grab the following files from mu/shared/class/engr/455/Adaptive Filter SDR Project/
- Convert the *.auf files (and not the *.au files) using Audacity, note the sampling rate
- Wave source allows you to play the converted *.wav files
- Bandpass filter to single out the 3kHz (and get rid of the 1/f noise at the same time)
- Shift down to baseband with a cosine wave
- Low pass filter to single out the signal at the baseband (and to throw out the signal at +/- 2f)
- Use your favorite sink to hear/see the results
Ls = length(Noise2); % Noise & SignalNoise is an Ls by 1 matrix. N = 20; % Length of adaptive filter h = zeros(N,1); % Adaptive filter coefficients mu = 1/(1000*N*var(Noise2)); % Need to change for k=N:Ls % Offset by the length of the adaptive filter to "start up" xk = Noise2(k:-1:(k-N+1)); % Flip shift nhat(k) = (h')*(xk'); % Multiply integrate e(k) = - SignalNoise(k) + nhat(k); % Error term h = h - mu*e(k)*xk'/(xk*xk'); % Dividing by D^2 makes it independant of mu end
- Is h the adaptive filter coefficients? Yes!
- When you save the voice, is it an Nx1 or 1xN matrix?
- whos (octave) will show all variables and their dimensions