matched_filter.m

MATLAB-functions used in Space-Time Project Simulation

function [mf_data_block]=matched_filter(fs, T, pulsetype, in_data_block)

%   [mf_data_block]=matched_filter(fs, T, pulsetype, in_data_block)
%
%	Output:
%	mf_data_block   - Output block after matched-filtering.
%   
%   Input:
%	fs              - Sampling frequency
%	T               - Symbol period
%	pulsetype       - One of:   pulsetype=1 -> square
%                               pulsetype=2 -> root-raised-cosine
%                               pulsetype=3 -> hamming
%                               pulsetype=4 -> raised-cosine
%	in_data_block   - Down-converted data-block
%   
%   Short Theoretical Background for the Function:
%
%   Performs the matched filtering of the down-converted signal.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     
%%% Function part of simulation for Space-Time
%%% coding project, group Grey-2001.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%   Author: Stefan Uppg錼d
%   Date: 2001-03-20
%   Version: 1.0
%   Revision (Name & Date): 
%   FH 2001-03-21  see line 35
%   FH 2001-04-06 added raised-cosine pulsetype
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

oversamp = fs*T;    % rev: T instead of 1/fc to get correct oversamp

%%%
%%% Selected pulsetype to matched-filter in_data_block to.
%%%

if  pulsetype == 1                         % copy of code from pulseshape.m
    p = ones(1,oversamp)/sqrt(oversamp);
elseif pulsetype == 2
    p = root_raised_cosine(oversamp);
elseif pulsetype == 3
    p = hamming(oversamp)';
elseif pulsetype == 4    
    p = raised_cosine(oversamp);
end

%%%
%%% Perform the matched-filtering by convolution.
%%%
mf_data_block = conv(p,in_data_block);