%Program 4.3
%giins.m
%
%Function to insert guard interval into transmission signal
%
%Copyed by lpch
%
function [iout,qout]=giins(idata,qdata,fftlen,gilen,nd);
%********************** variables ****************************************
%idata : Input Ich data
%qdata : Input Qch data
%iout  : Output Ich data
%qout  : Output Qch data
%fftlen: Length of FFT(points)
%gilen : Length of guard interval(points)
%*************************************************************************
idata1=reshape(idata,fftlen,nd);
qdata1=reshape(qdata,fftlen,nd);
idata2=[idata1(fftlen-gilen+1:fftlen,:);idata1];
qdata2=[qdata1(fftlen-gilen+1:fftlen,:);qdata1];

iout=reshape(idata2,1,(fftlen+gilen)*nd);
qout=reshape(qdata2,1,(fftlen+gilen)*nd);
%************************ end of file ************************************


%Program 4-4
%girem.m
%
%Function to remove guard interval from received signal
%
%Copyed by lpch
%
function [iout,qout]=girem(idata,qdata,fftlen2,gilen,nd);
%************************** variables ************************************
%idata : Input Ich data
%qdata : Input Qch data
%iout  : Output Ich data
%qout  : Output Qch data
%fftlen2 : Length of FFT(points)
%gilen : Length of guard interval(points)
%nd    : Number of OFDM symbols
%*************************************************************************
idata2=reshape(idata,fftlen2,nd);
qdata2=reshape(qdata,fftlen2,nd);
iout=idata2(gilen+1:fftlen2,:);
qout=qdata2(gilen+1:fftlen2,:);
%********************** end of file **************************************