add_start_seq.m

MATLAB-functions used in Space-Time Project Simulation

function [start_sequence,delayvec_length,sync]=add_start_seq(max_delay,window_length,pulsetype,fs,T)

%   [start_sequence,delay_length,sync]=add_start_seq(max_delay,window_length,pulsetype,fs,T,sync_factor)
%
%	Output:
%	start_sequence      - the sequence before the first symbolblock 
%   delayvec_length     - length before the powerburst starts
%   sync                - the synchronization sequence               
%   
%   Input:
%	max_delay           - max length before the powerburst starts
%   window_length       - length of each block
%   pulsetype           - decides wich pulseshape to be used
%   fs                  - sampling frequency  
%   T                   - symbol period
%   
%
%   Short Theoretical Background for the Function:
%   
%   Creates a startsequence to be added before the first symbolblock. The startsequence 
%   begins with a vector of zeros of random length according to delayvec_length. Then 
%   follows a powerburst, a gardblock, a synchronizationblock and a final gardblock.  
%   
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     
%%% Function part of simulation for Space-Time
%%% coding project, group Grey-2001.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%   Author: Fredrik & Karl
%   Date: 2001-04-27
%   Version: 1.0
%   Revision (Name & Date & Comment):
%   1.1 2001-05-02      longer sync and no gard after the sync-block
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

delayvec_length = max_delay + fs*T*ceil(max_delay*rand(1));
delayvec = zeros(1,delayvec_length);
power_burst = ones(1,fs*T*(window_length+10));
sync_length = 2*window_length+10;
sync_vec = bpsk(random_training(sync_length),0);
gard_vec = zeros(1,window_length);

%[power,t1]=pulseshape(power_burst,fs,pulsetype,T);
power = carrier(power_burst,2500,fs,T);
[sync,t1]=pulseshape(sync_vec,fs,pulsetype,T);
[gard,t1]=pulseshape(gard_vec,fs,pulsetype,T);

start_sequence = [delayvec power gard sync];