low_pass.m

来自「完整的空时码链路仿真多发射天线多接收天线空时分集系统的具体代码实现和误码性能评估」· M 代码 · 共 33 行

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);