anaqpsk.zip_四相编码_四相编码信号

function [y,pm0,jumps]=anaqpsk(N,Ncomp,f0); %ANAQPSK Quaternary Phase Shift Keying (QPSK) signal. % [Y,PM]=ANAQPSK(N,NCOMP,F0) returns a complex phase modulated signal % of normalized frequency F0, whose phase changes every NCOMP point according % to a discrete uniform law, between the values (0, pi/2, pi, 3*pi/2). % Such signal is only 'quasi'-analytic. % % N : number of points % NCOMP : number of points of each component (default: N/5) % F0 : normalized frequency. (default: 0.25) % Y : signal % PM0 : initial phase of each component (optional). % % Example : % [signal,pm0]=anaqpsk(512,64,0.05); clf; figure(gcf); % subplot(211); plot(real(signal)); subplot(212); plot(pm0); % % See also ANAFSK, ANABPSK, ANAASK. % O. Lemoine - October 1995 % Copyright (c) 1996 by CNRS (France). % % ------------------- CONFIDENTIAL PROGRAM -------------------- % This program can not be used without the authorization of its % author(s). For any comment or bug report, please send e-mail to % f.auger@ieee.org if (nargin == 0), error('The number of parameters must be at least 1.'); elseif (nargin == 1), Ncomp=round(N/5); f0=0.25; elseif (nargin == 2), f0=0.25; end; if (N <= 0), error('The signal length N must be strictly positive' ); elseif (f0<0)|(f0>0.5), error('f0 must be between 0 and 0.5'); end; MatlabVersion=version; MatlabVersion=str2num(MatlabVersion(1)); if (MatlabVersion==4), rand('uniform'); end; m=ceil(N/Ncomp); % jumps=round(3*rand(m,1)); % This is a modification proposed by Alpesh Patel, McMaster University jumps=floor(4*rand(m,1)); jumps(jumps==4)=3; jumps(1)=0; jumps=[0 1 2 3 0 3 0 3 0 3 2 1 0].'; jump_num=0; for m=1:length(jumps)-1 if jumps(m)~=jumps(m+1) jump_num=jump_num+1; end end jump_num % phase= xlsread('ppBC.xls', 'ppBC', 'B63:BL63'); % alphabet = xlsread('ppBC.xls', 'ppBC', 'A63'); % jumps=(phase*2*pi/alphabet).'/pi*2; pm0=pi*kron(jumps,ones(Ncomp,1))/2; pm0=pm0(1:N,1); tm=(1:N)'-1; pm=(2.0*pi*f0*tm+pm0); y = exp(j*pm);