jens
f59fb8f67d
git-svn-id: http://moon:8086/svn/matlab/trunk@100 801c6759-fa7c-4059-a304-17956f83a07c
55 lines
1.4 KiB
Objective-C
Executable File
55 lines
1.4 KiB
Objective-C
Executable File
## Copyright (C) 2018 Jens Ahrensfeld
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##
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## This program is free software; you can redistribute it and/or modify it
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## under the terms of the GNU General Public License as published by
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## the Free Software Foundation; either version 3 of the License, or
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## (at your option) any later version.
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##
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## This program is distributed in the hope that it will be useful,
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## but WITHOUT ANY WARRANTY; without even the implied warranty of
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## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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## GNU General Public License for more details.
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##
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## You should have received a copy of the GNU General Public License
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## along with this program. If not, see <http://www.gnu.org/licenses/>.
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## -*- texinfo -*-
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## @deftypefn {Function File} {@var{retval} =} qdemod_eval (@var{input1}, @var{input2})
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##
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## @seealso{}
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## @end deftypefn
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## Author: Jens Ahrensfeld <ahrensfeld@w2ess001vm>
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## Created: 2018-11-16
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function qdemod_eval
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fa = 1000;
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T = 1/fa;
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N = 1000
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t = (0:N-1)*T;
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omega_x_0 = 100.0;
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omega_x_1 = 200.0;
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phi_x = pi/8*0;
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omega_lo = 150.0;
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lo_r = cos(2*pi*omega_lo*t);
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lo_i = sin(2*pi*omega_lo*t);
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x = cos(2*pi*omega_x_0*t + phi_x) + cos(2*pi*omega_x_1*t + phi_x);
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y = x.*lo_r + x.*lo_i*i;
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subplot(2,1,1);
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plot(t, y, t, x); grid;
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subplot(2,1,2);
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Y = fftshift(fft(y, N))/N;
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X = fftshift(fft(x, N))/N;
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f = (-length(X)/2:length(X)/2-1)/N*fa;
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plot(f, abs(X), f, abs(Y)); grid;
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endfunction
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