Mercurial > forge
view main/comm/inst/apkconst.m @ 9666:67d4cfc5eeb3 octave-forge
comm: update license to GPLv3+
author | carandraug |
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date | Tue, 13 Mar 2012 04:31:21 +0000 |
parents | 2de537641f94 |
children | fe6da9839797 |
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## Copyright (C) 2003 David Bateman ## ## This program is free software; you can redistribute it and/or modify it under ## the terms of the GNU General Public License as published by the Free Software ## Foundation; either version 3 of the License, or (at your option) any later ## version. ## ## This program is distributed in the hope that it will be useful, but WITHOUT ## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or ## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more ## details. ## ## You should have received a copy of the GNU General Public License along with ## this program; if not, see <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {Function File} {} apkconst (@var{nsig}) ## @deftypefnx {Function File} {} apkconst (@var{nsig},@var{amp}) ## @deftypefnx {Function File} {} apkconst (@var{nsig},@var{amp},@var{phs}) ## @deftypefnx {Function File} {} apkconst (@var{...},"n") ## @deftypefnx {Function File} {} apkconst (@var{...},@var{str}) ## @deftypefnx {Function File} {@var{y} = } apkconst (@var{...}) ## ## Plots a ASK/PSK signal constellation. Argument @var{nsig} is a real vector ## whose length determines the number of ASK radii in the constellation. ## The values of vector @var{nsig} determine the number of points in each ## ASK radii. ## ## By default the radii of each ASK modulated level is given by the index of ## @var{nsig}. The amplitudes can be defined explictly in the variable ## @var{amp}, which is a vector of the same length as @var{nsig}. ## ## By default the first point in each ASK radii has zero phase, and following ## points are coding in an anti-clockwise manner. If @var{phs} is defined then ## it is a vector of the same length as @var{nsig} defining the initial phase ## in each ASK radii. ## ## In addition @dfn{apkconst} takes two string arguments 'n' and and @var{str}. ## If the string 'n' is included in the arguments, then a number is printed ## next to each constellation point giving the symbol value that would be ## mapped to this point by the @dfn{modmap} function. The argument @var{str} ## is a plot style string (example 'r+') and determines the default gnuplot ## point style to use for plot points in the constellation. ## ## If @dfn{apskconst} is called with a return argument, then no plot is ## created. However the return value is a vector giving the in-phase and ## quadrature values of the symbols in the constellation. ## @end deftypefn ## @seealso{dmod,ddemod,modmap,demodmap} ## 2005-04-23 Dmitri A. Sergatskov <dasergatskov@gmail.com> ## * modified for new gnuplot interface (octave > 2.9.0) function yout = apkconst(varargin) if ((nargin < 1) || (nargin > 5)) error ("apkconst: incorrect number of arguments"); endif numargs = 0; printnums = 0; fmt = "+r"; amp = []; phs = []; for i=1:length(varargin) arg = varargin{i}; if (ischar(arg)) if (strcmp(arg,"n")) try text(); printnums = 1; catch printnums = 0; end else fmt = arg; endif else numargs++; switch (numargs) case 1, nsig = arg; case 2, amp = arg; case 3, phs = arg; otherwise error ("apkconst: too many numerical arguments"); endswitch endif end if (numargs < 1) error ("apkconst: must have at least one vector argument"); endif if (isempty(amp)) amp = 1:length(nsig); endif if (isempty(phs)) phs = zeros(size(amp)); endif if (!isvector(nsig) || !isvector(amp) || !isvector(phs) || ... (length(nsig) != length(amp)) || (length(nsig) != length(phs))) error ("apkconst: numerical arguments must be vectors of the same length"); endif if (length(nsig) == 0) error ("apkconst: first numerical argument must have non-zero length"); endif y = []; for i=1:length(nsig) if (nsig(i) < 1) error ("apkconst: must have at least one point in ASK radii"); endif y = [y; amp(i) * [cos(2*pi*[0:nsig(i)-1]'/nsig(i) + phs(i)) + ... 1i*sin(2*pi*[0:nsig(i)-1]'/nsig(i) + phs(i))]]; end if (nargout == 0) r = [0:0.02:2]'*pi; x0 = cos(r) * amp; y0 = sin(r) * amp; plot(x0, y0, "b"); yy = [real(y), imag(y)]; hold on; if (printnums) xd = 0.05 * max(real(y)); for i=1:length(y) text(real(y(i))+xd,imag(y(i)),num2str(i-1)); end endif plot (real(y), imag(y), fmt); title("ASK/PSK Constellation"); xlabel("In-phase"); ylabel("Quadrature"); else yout = y; endif endfunction