obje.m

多载波调制的仿真程序

%PERFORM Evaluate the performance of an TEQ in terms of
% SSNR, SNR, geometric SNR, and channel capacity.
% [SS, S, Si, Sg, Mg, Bf, Bm, Rf, Rm, Hw, Fh, Fw, Nc, Fhw] = 
% PERFORM(W,B,H,D,Nb,NN,X,N,Ph,Px,Pn,M,C,Fs,Mi) returns
% the shortening SNR in SS, the SNR at the output of the 
% equalizer in S, the SNR distribution over the subchannels
% in the vector Si. Sg is the real geometric SNR achieved
% with the TEQ and Mg is the geometric SNR that can be 
% achieved in the case of zero ISI (Mg is calculated using
% the MFB distribution while Sg is calculated with the SNR
% distribution.). Bf is the number of bits per symbol 
% achievable with the TEQ and Bm is the upperbound on
% bits per symbol. Rf is the channel capacity achieved with 
% the TEQ and Rm is the upperbound on the channel capacity.
% Hw is a vector containing the equalized channel impulse 
% response. Fh is a vector containing the frequency response 
% of the original channel and Fw is vector containing the 
% equalizer. Nc is a vector of the power spectrum of the 
% channel noise after equalization and Fhw is a vector 
% containing the frequency response of the equalized channel.
%
% W is TEQ impulse response. B is the target impulse response
% (for MMSE based techniques). H is the channel impulse
% response. D is the optimal delay with TEQ. Nb is the target
% window size. NN is the FFT size used in the DMT modulation.
% X is the transmitted signal. N the channel noise. Ph is the 
% magnitude square of the channel frequency response. 
% Px is the power spectrum of the transmitted signal. Pn is the 
% power spectrum of the channel noise. M is the desired system 
% margin in dB which is used for channel capacity calculations.
% C is the coding gain in dB assumed for channel capacity 
% calculations. Fs is the sampling frequency. Mi is the matched
% filter bound distribution over frequency.

% Copyright (c) 1999-2002 The University of Texas
% All Rights Reserved.
%  
% This program is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation; either version 2 of the License, or
% (at your option) any later version.
%  
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
%  
% The GNU Public License is available in the file LICENSE, or you
% can write to the Free Software Foundation, Inc., 59 Temple Place -
% Suite 330, Boston, MA 02111-1307, USA, or you can find it on the
% World Wide Web at http://www.fsf.org.
%  
% Programmers:	Guner Arslan
% Version:      @(#)perform.m	1.3  09/25/00
% 
% The authors are with the Department of Electrical and Computer
% Engineering, The University of Texas at Austin, Austin, TX.
% They can be reached at [e-mail].
% Guner Arslan is also with the Embedded Signal Processing
% Laboratory in the Dept. of ECE., http://anchovy.ece.utexas.edu.

function y = obje(W,channel,D,Nb,N,inputSpec,noiseSpec,margin,codingGain,fs,used)
W = W/norm(W);
hw = filter(W,1,channel);
win = zeros(length(hw),1); 
win(D+1:D+Nb) = ones(1,Nb); 
hwin = hw.*win;               
hwout = hw.*(1-win);                    
Fwu = fft(W,N)*sqrt(N); Fw = Fwu(1:N/2+1).';  %Fw = Fw(used);
Fhwinu = fft(hwin,N)*sqrt(N); Fhwin = Fhwinu(1:N/2+1).'; %Fhwin = Fhwin(used);
Fhwoutu = fft(hwout,N)*sqrt(N); Fhwout = Fhwoutu(1:N/2+1).'; %Fhwout = Fhwout(used);
Fhwin = Fhwin(used);
Fhwout = Fhwout(used);
Fw = Fw(used);

colorNoiseaft = noiseSpec.*abs(Fw).^2;  
isiaft = inputSpec.*abs(Fhwout).^2;   
signalaft = inputSpec.*abs(Fhwin).^2;    
SNRi = signalaft./( colorNoiseaft + isiaft );  
[geoSNRfinal bDMTfinal RDMTfinal] = geosnr(SNRi,margin,codingGain,N,Nb,fs);

y = -bDMTfinal;