mctc_dec.m

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%  Property of Freescale
%  Freescale Confidential Proprietary
%  Freescale Copyright (C) 2005 All rights reserved
%  ----------------------------------------------------------------------------
%  $RCSfile: mCTC_dec.m.rca $
%  $Revision: 1.1 $
%  $Date: Mon Jan 22 10:59:12 2007 $
%  Target: Matlab
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%
%  CTC decoder (INT3e version: no HARQ, no feedback, no SPID)
%  Input:
%   In          : input data (vector or matrix)
%   BlockSize   : data size
%   nIter       : number of iteration for CTC decoder
%   Type        : FEC info
%
%  Output:
%   Out         : output data (vector or matrix)
%   BlockSize   : data size

function [Out,BlkSize] = mCTC_dec (In,BlockSize,nIter,Type)


%-- Parameters setting
switch Type
    case 0 % QPSK rate 1/2
        rate = 2 ;
    case 1 % QPSK rate 3/4
        rate = 4/3 ;
    case 2 % 16QAM rate 1/2
        rate = 2 ;
    case 3 % 16QAM rate 3/4
        rate = 4/3 ;
    case 4 % 64QAM rate 1/2
        %tbd
    case 5 % 64QAM rate 2/3
        %tbd
    case 6 % 64QAM rate 3/4
        %tbd
    otherwise
        error('Unknown FEC Type')
end
Nep = BlockSize./rate;

%loop over col of In
for i=1:size(In,2)

    clear dec_y inputA inputB

    %-- De-puncture
    de_puncturing = [ In(1:BlockSize(i),i)' zeros(1, (Nep(i)*3 -BlockSize(i)))];

    %-- Degrouping
    de_group = mCTC_degrouping(de_puncturing); %to move

    %-- Subblock deinterleaving
    sub_deinter_y = mCTC_SubDIL(de_group);%to move


    % Format change (easy for reading)
    x_sysA = sub_deinter_y(1,:);
    x_sysB = sub_deinter_y(2,:);
    parity_y1 = sub_deinter_y(3,:);
    parity_y2 = sub_deinter_y(4,:);
    parity_w1 = sub_deinter_y(5,:);
    parity_w2 = sub_deinter_y(6,:);

    % Get the input data for both decoders
    % 1st decoder: A, B, Y1, W1
    % 2nd decoder: interleaved_A, interleaved_B, Y2, W2
    dec_y(1,:) = reshape([x_sysA;x_sysB;parity_y1;parity_w1],1,Nep(i)*2);

    % IL
    [inputA,inputB] = mCTC_ILDIL(Nep(i),x_sysA,x_sysB) ;

    dec_y(2,:) = reshape([inputA;inputB;parity_y2;parity_w2],1,Nep(i)*2);

    % single Turbo decoder
    Out(1:Nep(i),i) = mCTC_RSCDec(dec_y, Nep(i), nIter);
    BlkSize(i)=Nep(i);
end

%data packing
Out = mBytePack(Out);
BlkSize=(BlkSize)/8;