function [lp_data_block]=low_pass(cutoff_freq, order, data_block)%   [lp_data_block]=low_pass(cutoff_freq, order, data_block)%%	Output:%	lp_data_block   - The lowpass-filtered version of data_block%	%   Input:%   cutoff_freq     - Desired cutoff frequency for the filter%   order           - Butterworth filter of this order is used when filtering%   data_block      - The input data_block to be filtered%%   Short Theoretical Background for the Function:%%   Low-pass filters the input datablock. This function is%   probably called from the function down_converter.%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     %%% 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):%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%[B,A]=butter(order, cutoff_freq);           % cutoff_freq have to be chosen to eliminate                                            % high-frequency parts after down-conversion.lp_data_block = filter(B,A,data_block);