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function y=MaiMpathChannel(MAIUplinkSignal,MPathDelay,MPathAmpl,fDoppler,SamplesPerChip,cnt) 
%****************************************************************************** 
%function y=MaiMpathChannel(MAIUplinkSignal,MPathDelay,MPathAmpl,fDoppler) 
% 
% Copyright 2002 The Mobile and Portable Radio Research Group 
% 
%Generates the approximate multipath response for a particular Mutual Access  
%Interference (MAI) signal.  The number of multipath components is equal to the 
%length of "MPathDelay", which contains the relative delay of each component in 
%terms of signal samples.  For each multipath component the input signal, 
%"MAIUplinkSignal", is shifted IN A CIRCULAR FASHION by the number of samples 
%specified in "MPathDelay".  Then, the shifted signal is then multiplied by  
%a fading signal whose average power equals the corresponding value in  
%"MPathAmpl".  The bandwidth of the fading signal is determined by the Doppler 
%spread, "fDoppler".   
% 
%The multipath components are then summed together to form the overal multipath  
%response 
% 
%Parameters 
%   Input 
%      MAIUplinkSignal   vector   Uplink signal from one interferer 
%      MPathDelay        vector   Relative delay of each multipath component 
%                                 expressed in terms of signal samples 
%      MPathAmpl         vector   Average power in each multipath component 
%      fDoppler          scalar   Doppler spread in Hz 
%      SamplesPerChip    scalar   SamplesPerChip 
%   Output 
%      y                 vector   Response of signal due to the multipath channel 
%****************************************************************************** 
MPathComponents=length(MPathDelay); 
ChipsPerFrame=38400; 
FrameDuration=10e-3; 
SampleRate=SamplesPerChip*ChipsPerFrame/FrameDuration; 
SigLength=length(MAIUplinkSignal); 
SigDuration=SigLength/SampleRate; 
FadeSampleRate=20/SigDuration; 
if length(MPathAmpl) ~= MPathComponents 
   error('MPathDelay and MPathAmpl must have the same length'); 
end 
increment=(SigLength-1)/20; 
%Abcissa for data points 
x=1:increment:(SigLength); 
%Abcissa for interpolation 
xi=1:SigLength; 
y=zeros(1,SigLength); 
for k=1:MPathComponents 
   %Get Fading sample values 
   FadeSamples=MPathAmpl(k)*rayleigh(fDoppler,FadeSampleRate,21); 
%   Fade=interp1(x,FadeSamples,xi,'*cubic'); 
   Fade=WCDMACubicInterp(x,FadeSamples,xi).'; 
   y=y+Fade.*[MAIUplinkSignal((SigLength-MPathDelay(k)+1):SigLength) MAIUplinkSignal(1:(SigLength-MPathDelay(k)))]; 
end