function [s_antenna1, s_antenna2]=alamouti(symbol_block,set)%   [s_antenna1, s_antenna2]=alamouti(symbol_block,set)%%	Output:%	s_antenna1	    - Symbolstream to be put on antenna 1. (symbol-vector)%	s_antenna2	    - Symbolstream to be put on antenna 2. (symbol-vector)%   %   Input:%   symbol_block    - block of symbols to be alamouti-coded (REAL VALUED SYMBOLS!) (symbol-vector)%   set             - if set to 0, no alamouti coding is performed. (int 0,1)%                     if set to 1, alamouti coding is performed.%%   Short Theoretical Background for the Function:%%   Space-Time coding for two antennas, using the alamouti algorithm.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     %%% Function part of simulation for Space-Time%%% coding project, group Grey-2001.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   Author: Stefan Uppg錼d%   Date: 2001-03-19%   Version: 1.1%   Revision (Name & Date): FH 2001-03-28 see line 40%   2.0 FH 2001-04-01   clever vector implementation%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% set = 0, put all data in antenna nr.1if(set==0)    s_antenna1 = symbol_block;    s_antenna2 = zeros(1,length(symbol_block));elseif(set==1)        a = ones(1,length(symbol_block));    a(2:2:end) = -1*a(2:2:end);    %s_antenna1 = (diag(symbol_block)*a')';  % [s0 -s1 s2 -s3 ...]    s_antenna1 = a.*symbol_block;           % should be the same as with diag    s_antenna2 = [];             odd = zeros(1,length(symbol_block));    even = odd;    odd(1:2:end) = symbol_block(2:2:end);    even(2:2:end) = symbol_block(1:2:end);    s_antenna2 = odd + even;     else    s_antenna1 = symbol_block;    s_antenna2 = [];end