function [dlt,slt] = ltable(md,s,varargin)%LTABLE Space-time code look-up table generator.%   [DLT,SLT] = LTABLE(MD,S) creates MD, S-states space-time code data%   and state look-up tables. MD corresponds to the number of %   constellation signals e.g. MD-PSK and MD-QAM. The summary of%   available designs is listed below. %%   Table of available designs%%     #  |  MD | MODULATION | STATES |   METHOD%   -----+-----+------------+--------+-------------%     1. |  4  |    PSK     |    4   |   'att'%     2. |  4  |    PSK     |    8   |   'att'%     3. |  4  |    PSK     |   16   |   'att'%     4. |  4  |    PSK     |   32   |   'att'%     5. |  8  |    PSK     |    8   |   'att'%     6. |  8  |    PSK     |    8   |  'delay'%     7. |  8  |    PSK     |   16   |   'att'%     8. |  8  |    PSK     |   32   |   'att'%     9. | 16  |    QAM     |   16   |   'att'%    10. | 16  |    QAM     |   16   |  'delay'%    11. | 16  |    QAM     |   16   |   'ext'%%   [DLT,SLT] = LTABLE(MD,S,'PropertyName',PropertyValue,...)%%   Ltable Property List%%   Method         {'att'} | 'delay' | 'ext'%   Echo           'on' | {'off'}%%   See also DISPDES, SPACE.%   Copyright 2001-2003 Kamil Anis, anisk@feld.cvut.cz%   Dept. of Radioelectronics, %   Faculty of Electrical Engineering%   Czech Technical University in Prague%   $Revision: 2.1 $  $Date: 2003/1/16 17:33:28 $%   --%   <additional stuff goes here>global ECHOname = 'LTABLE';[idt,tag] = iecho(name);nopts = length(varargin) / 2;opts = reshape(varargin,[2 nopts])';ord1 = strmatch('Echo',opts(:,1));ord2 = strmatch('Method',opts(:,1));% Echoif ~isempty(ord1) % first check whether local option exists	value1 = opts{ord1,2};	switch value1	case 'on'		ech = 1;	case 'off'		ech = 0;	otherwise		disp(' ');		disp([tag,'Invalid option for Echo property.']);		disp([idt,'Possible values are ''on''|{''off''}.']);		disp(' ');		ech = 0;	endelse	if ~isempty(ECHO) % than check whether global option exists		switch ECHO		case 'on'			ech = 1;		case 'off'			ech = 0;		otherwise			disp(' ');			disp([tag,'Invalid option for Echo property.']);			disp([idt,'Possible values are ''on''|{''off''}.']);			disp(' ');			ech = 0;		end	else % if there are no settings use the defaults		ech = 0; % default value	endend% Methodif isempty(ord2) % there's no such option	method = 'att'; % default valueelse % there's relevant option	method = opts{ord2,2};end%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% BODY BEGIN %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% State matrix generatorbase = reshape(1:s,md,s/md)';slt = repmat(base,md,1);% Data matrix generator% block code of 16QAMload stc_bc16.txt;for j = 1:md	l = j - 1;		ak = bitget(l,1);	bk = bitget(l,2);	dk = bitget(l,3);	ek = bitget(l,4);		switch md	% 4 PSK	case 4		for i = 1:s			k = i - 1;						ak_1 = bitget(k,1);			bk_1 = bitget(k,2);			ak_2 = bitget(k,3);			bk_2 = bitget(k,4);			ak_3 = bitget(k,5);			bk_3 = bitget(k,6);						switch s			case 4				dlt(i,j,1) = mod(2 * bk_1 + ak_1,md);				dlt(i,j,2) = mod(2 * bk + ak,md);			case 8				dlt(i,j,1) = mod(2 * ak_2 + 2 * bk_1 + ak_1,md);				dlt(i,j,2) = mod(2 * ak_2 + 2 * bk + ak,md);			case 16				dlt(i,j,1) = mod(2 * ak_2 + 2 * bk_1 + ak_1,md);				dlt(i,j,2) = mod(2 * bk_2 + 2 * ak_1 + 2 * bk + ak,md);            			case 32				dlt(i,j,1) = mod(2 * ak_3 + 3 * bk_2 + 2 * ak_2 + 2 * bk_1 +...					ak_1,md);				dlt(i,j,2) = mod(2 * ak_3 + 3 * bk_2 + 2 * bk_1 + ak_1 + 2 *...          bk + ak,md);			end		end		% 8 PSK	case 8		for i = 1:s			k = i - 1;						ak_1 = bitget(k,1);			bk_1 = bitget(k,2);			dk_1 = bitget(k,3);			ak_2 = bitget(k,4);			bk_2 = bitget(k,5);						switch s			case 8        				switch method				case 'att'					dlt(i,j,1) = mod(4 * dk_1 + 2 * bk_1 + 5 * ak_1,md);					dlt(i,j,2) = mod(4 * dk + 2 * bk + ak,md);                  case 'delay'					dlt(i,j,1)=mod(4 * dk_1 + 2 * bk_1 + ak_1,md);					dlt(i,j,2)=mod(4 * dk + 2 * bk + ak,md);				end							case 16				dlt(i,j,1) = mod(ak_2 + 4 * dk_1 + 2 * bk_1 + 5 * ak_1,md);				dlt(i,j,2) = mod(5 * ak_2 + 4 * dk_1 + 2 * bk_1 + ak_1 + 4 *...          dk + 2 * bk + ak,md);			case 32				dlt(i,j,1) = mod(2 * bk_2 + 3 * ak_2 + 4 * dk_1 + 2 * bk_1 +...          5 *	ak_1,md);				dlt(i,j,2) = mod(2 * bk_2 + 7 * ak_2 + 4 * dk_1 + 2 * bk_1 +...					ak_1 + 4 * dk + 2 * bk + ak,md);			end		end		% 16 QAM	case 16		for i = 1:s			k = i - 1;						ak_1 = bitget(k,1);			bk_1 = bitget(k,2);			dk_1 = bitget(k,3);			ek_1 = bitget(k,4);						switch s			case 16			        switch method				case 'att'					dlt(i,j,1) = mod(8 * ek_1 + 4 * dk_1 + 2 * bk_1 + 11 *...            ak_1,md);					dlt(i,j,2) = mod(16 * ek_1 + 16 * dk_1 + 16 * bk_1 + 16 *...						ak_1 + 8 * ek + 4 * dk + 2 * bk + ak,md);                case 'delay'					dlt(i,j,1) = mod(8 * ek_1 + 4 * dk_1 + 2 * bk_1 + ak_1,md);					dlt(i,j,2) = mod(8 * ek + 4 * dk + 2 * bk + ak,md);                  case 'ext'					dlt(i,j,1) = stc_bc16(k + 1,1);					dlt(i,j,2) = stc_bc16(k + 1,2) - i + j;				end			end		end	endend%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% BODY END %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%if ech		str1 = num2str(md);		str2 = num2str(s);				if (md == 4) | (md == 8)      str3 = 'PSK';		else      str3 = 'QAM';		end				disp(' ');		disp([tag,'Look-up tables for ',method,' code ',str1,str3,', ',...        str2,'-states created.']);		disp(' ');end