estphaseoffset.m

用matlab程序实现WCDMA系统的仿真

function z = EstPhaseOffset(SoftCntlSig,DPCCH_code,N_pilot)
%****************************************************************************
%function z = EstPhaseOffset(BeamformedCntlSig,DPCCH_code,N_pilot)
%
% Copyright 2002 The Mobile and Portable Radio Research Group
%
%Uses the received symbols in the control channel to estimate the phase offset
%Only the pilot symbols are used in the estimate
%This routine provides a phase offset estimate for each of the 15 slots in a 
%WCDMA frame
%
%Parameters
%   Input
%      BeamformedCntlSig   vector   Estimated control signal
%      DPCCH_code          vector   True control signal
%      N_pilot             scalar   Number of pilot symbols in time slot
%                                   between 3 and 8.
%   Output
%      z                   scalar   phase offset
%****************************************************************************
index=[];
for k=0:14
   index=[index 10*k+(1:N_pilot)];
end

%Extract Pilot symbols and correstponding soft detected symbols
CorrectBits=DPCCH_code(index);
DetectedBits=SoftCntlSig(index);

%Normalized soft detected symbols
NormalizedDetectedBits=DetectedBits./abs(DetectedBits);

for k=1:15
   index=(k-1)*N_pilot+(1:N_pilot);
   %Compute Phase differences
   PhaseOffset=CorrectBits(index)./NormalizedDetectedBits(index);
   %Average the phase offsets
   z(k)=mean(PhaseOffset);
end