function [outdata_block,training_sequence]=add_training(data_block,training_length,type)%   [outdata_block,training_sequence]=add_training(data_block,training_length,type)%%	Output:%	outdata_block	    - Training sequence and datablock (symbol-vector)%   training_sequence   - The first training sequence, which also is concatenated in outdata_block (binary-vector)%	%   Input:%   data_block          - Alamouti-coded symbols. (symbol-vector)%   training_length     - Desired length of training sequence (even int)%   type                - Specifies which kind of training sequence to be added (int 0,1)%                           if type = 0, a random sequence is used.%%   Short Theoretical Background for the Function:%%   Instead of adding binary training-data to the original data-sequence, %   this function adds bpsk symbols after alamouti-coding is performed%   so that the training-sequence will not be alamouti-coded.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     %%% Function part of simulation for Space-Time%%% coding project, group Grey-2001.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   Author: Stefan Uppg錼d%   Date: 2001-03-19%   Version: 1.0%   Revision (Name & Date):%   2.0 SU  2001-04-04  Adds bpsk-symbols to data. Function supposed to be called%                       after that Alamouti-coding already has been performed.%                       This function uses the model parameter and adds two%                       training-sequences when a 2x? is used.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%home_made_training = [];for(i=1:30)    home_made_training = [home_made_training 1];    home_made_training = [home_made_training zeros(1,i)];end% type = 0 -> call for a random training sequence.if (type==0)    training_sequence = random_training(training_length);elseif (type==1)    training_sequence = home_made_training(1:training_length); else                                training_sequence = [];end % type == 0training_sequence_symb = bpsk(training_sequence,0);outdata_block = [training_sequence_symb data_block];