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diff --git a/octave/cma.m b/octave/cma.m
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--- a/octave/cma.m
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-% cma.m
-%
-% Constant modulus equaliser example from:
-%
-% http://dsp.stackexchange.com/questions/23540/matlab-proper-estimation-of-weights-and-how-to-calculate-mse-for-qpsk-signal-f
-%
-% Adapted to run bpsk and fsk signals
-
-    rand('seed',1);
-    randn('seed',1);
-
-    N = 5000;           % # symbols
-    h = [1 0 0 0 0 0 0.0 0.5];  % simulation of HF multipath channel impulse response
-    h = h/norm(h);
-    Le = 20;            % equalizer length
-    mu = 1E-3;          % step size
-    snr = 30;           % snr in dB
-    M = 10;             % oversample rate, e.g. Rs=400Hz at Fs=8000Hz
-
-    tx_type = "fsk";   % select modulation type here "bpsk" or "fsk"
-
-    if strcmp(tx_type, "bpsk")
-      s0 = round( rand(N,1) )*2 - 1;     % BPSK signal
-      s0M = zeros(N*M,1);                % oversampled BPSK signal
-      k = 1;
-      for i=1:M:N*M
-       s0M(i:i+M-1) = s0(k);
-        k ++;
-      end
-    end
-
-    if strcmp(tx_type, "fsk")
-      tx_bits = round(rand(1,N));
-
-      % continuous phase FSK modulator
-
-      w1 = pi/4;
-      w2 = pi/2;
-      tx_phase = 0;
-      tx = zeros(M*N,1);
-
-      for i=1:N
-        for k=1:M
-          if tx_bits(i)
-            tx_phase += w2;
-          else
-            tx_phase += w1;
-          end
-          tx((i-1)*M+k) = exp(j*tx_phase);
-        end
-      end
-
-      s0M = tx;
-    end
-
-    s = filter(h,1,s0M);                % filtered signal
-
-    % add Gaussian noise at desired snr
-
-    n = randn(N*M,1);
-    vs = var(s);
-    vn = vs*10^(-snr/10);
-    n = sqrt(vn)*n;
-    r = s + n;          % received signal
-
-    e = zeros(N*M,1);   % error
-    w = zeros(Le,1);    % equalizer coefficients
-    w(Le)=1;            % actual filter taps are flipud(w)!
-
-    yd = zeros(N*M,1);
-
-    for i = 1:N*M-Le,
-        x = r(i:Le+i-1);
-        y = w'*x;
-        yd(i)=y;
-        e(i) = abs(y).^2 - 1;
-        w = w - mu * e(i) * real(conj(y) * x);
-    end
-
-    np = 100;           % # sybmols to plot (last np will be plotted); np < N!
-
-    figure(1); clf;
-    %subplot(211), plot( 1:np, e(N-np+1-Le+1:N-Le+1).*e(N-np+1-Le+1:N-Le+1)), title('error')
-    subplot(211), plot(e.*e), title('error');
-    subplot(212), stem(conv(flipud(w),h)), title('equalized channel impulse response')
-
-    figure(2); clf;
-    subplot(311)
-    plot(1:np, s0M(N-np+1:N))
-    title('transmitted, received, and equalized signal')
-    subplot(312)
-    plot(1:np, r(N-np+1:N))
-    subplot(313)
-    plot(1:np, yd(N-np+1-Le+1:N-Le+1))
-
-    figure(3); clf;
-    h1 = freqz(h);
-    h2 = freqz(flipud(w));
-    h3 = freqz(conv(flipud(w),h));
-    subplot(311); plot(20*log10(abs(h1)));
-    title('channel, equaliser, combined freq resp')
-    subplot(312); plot(20*log10(abs(h2)));
-    subplot(313); plot(20*log10(abs(h3)));
-
-    figure(4);
-    subplot(211)
-    plot(20*log10(abs(fft(s0M))))
-    axis([1 length(s0M) 0 80]);
-    grid;
-    subplot(212)
-    plot(20*log10(abs(fft(s))))
-    axis([1 length(s0M) 0 80]);
-    grid;
-