guibene
84fb51d88c
git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4306 818b1a75-f10b-46b9-bf7c-635c3b92a50f
50 lines
911 B
Matlab
50 lines
911 B
Matlab
card=0;
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s = oarf_get_frame(card);
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%s=s-0.99999*mean(s(:,2));
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sig0 = s(:,1);
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sig1 = s(:,2);
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#sig0 = s(5000:end,1); % first channel
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#sig1 = s(5000:end,2); % 2nd channel
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bw=7.68e6;
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spec = abs(fft(sig1)).^2;
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%[a,b] = max(spec(2:end)); b=b+1;
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[a,b] = max(spec);
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freq = (b-1)*bw/length(sig0);
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L= 1000;
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W = 1;
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offset_vec = (0:L-1)*((2*W)+1);
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W2 = 1+(2*W);
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window_vec = (-W : W);
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pn = zeros(1,(2*L) - 1);
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for i = 1:L,
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pn(i+L-1) = sum(spec(offset_vec(i) + b + window_vec));
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end
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for i = 2:L,
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pn(L-i+1) = sum(spec(-offset_vec(i) + b + window_vec));
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end
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pn_2 = 10*log10(pn / pn(L)) - 10*log10(W2*bw/length(sig0));
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f = ((-L+1):(L-1))*W2*bw/length(sig0);
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ylabel('dBc/Hz')
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xlabel("f_offset (Hz)")
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title("Phase Noise @ IQ output for Fc = 1912.6 + Fs/4 MHz CW input at antenna")
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semilogx(f(L:(2*L - 1)),pn_2(L:(2*L -1)))
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grid on
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axis([1e2 100e3 -90 -30]);
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sum(pn*(f(2)-f(1)))
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signal_amp = 10*log10(pn(L))
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