find_sttc.m

通信中常用的卷积码信道译码源码程序

function [ST_NextState, ST_Output] = ...
    find_sttc(STTCFile, modulation_type, number_of_states);

%------------------------------------------------------------------------------
% Find Tarokh space-time code trellis structures.
% 
% Format:
% -------
% 
% [ST_NextState, ST_Output] = ...
%   find_sttc(STTCFile, modulation_type, number_of_states)
% 
% Author: MVe
% Date:   26.07.2002
%------------------------------------------------------------------------------

% Convert number to string
number_of_states_s = num2str(number_of_states);

% Open file, read it to variable 'STTC' and close file
FileID= fopen(STTCFile,'r');
STTC = fread(FileID);
fclose(FileID);

% Find correct trellis structure
MatchB = ...
    ['#define ', modulation_type, ' ',number_of_states_s,'-state STTC begins'];
BCode = findstr(char(STTC)',MatchB);
MatchE = ...
    ['#define ', modulation_type, ' ',number_of_states_s,'-state STTC ends'];
ECode = findstr(char(STTC)',MatchE);
STTC = STTC(BCode(1)+length(MatchB):ECode(1)-1);

% Insert trellis structure to variables
eval(char(STTC).');

% Convert 'ST_NextState' and 'ST_Output' to "pointer" format
size_o = size(Output);
ST_NextState = NextState+1;
ST_Output = reshape(num2cell([Output{:,:}]+1,[1,3]),size_o);