waterfillingpowerallo.m

该程序中包括为一个CDMA和OFDM的信道分配仿真程序。

% Copyright (c) 2003-2004 The University of Texas
% All Rights Reserved.
%  
% 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 2 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.
%  
% The GNU Public License is available in the file LICENSE, or you
% can write to the Free Software Foundation, Inc., 59 Temple Place -
% Suite 330, Boston, MA 02111-1307, USA, or you can find it on the
% World Wide Web at http://www.fsf.org.
%  
% Programmers:	Zukang Shen
% 
% The authors are with the Department of Electrical and Computer
% Engineering, The University of Texas at Austin, Austin, TX.
% They can be reached at [e-mail].

function PowerAllo= waterfillingPowerAllo(Ptot,eigenVec)
eigenVec=eigenVec+1e-10;
eigenVec=eigenVec(:);
[sortedEigVec,oriPosition]=sort(eigenVec);

EigVecTemp=sortedEigVec;

begin=1;
while sum((EigVecTemp-EigVecTemp(1)*ones(length(EigVecTemp),1))./(EigVecTemp*EigVecTemp(1)))>Ptot
    EigVecTemp=EigVecTemp(2:length(EigVecTemp));
    begin=begin+1;
end

P1=(Ptot-sum((EigVecTemp-EigVecTemp(1)*ones(length(EigVecTemp),1))./(EigVecTemp*EigVecTemp(1))))/length(EigVecTemp);
for i=1:begin-1
    PowerAlloOrdered(i)=0;
end

PowerAlloOrdered(begin)=P1;

for i=2:length(EigVecTemp)
    PowerAlloOrdered(begin+i-1)=P1+(EigVecTemp(i)-EigVecTemp(1))/(EigVecTemp(i)*EigVecTemp(1));
end

for i=1:length(eigenVec)
    PowerAllo(oriPosition(i))=PowerAlloOrdered(i);
end

sumCapa=0;
for i=1:length(eigenVec)
    sumCapa=sumCapa+log2(1+PowerAllo(i)*eigenVec(i));
end

mu=P1+1/EigVecTemp(1);
capacity=sum(log2(mu*EigVecTemp));