dfec_global.m

基于Matlab

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% CHANNEL PARAMETERS %
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% c      channel coefficients, either baud- or fractionally-spaced, 
%        normalized if normalization button is on
% Nc     length of c
% ca     for FSE odd subchannel coefficients, ca=c(1:2:Nc) baud-spaced; 
%        for BSE ca=[]
% cb     for FSE even subchannel coefficients, cb=c(2:2:Nc) for baud-spaced; 
%        for BSE cb=[]
%
% C      frequency response of c
% Ca     for FSE frequency response of ca; for BSE Ca=[]  
% Cb     for FSE frequency response of cb; for BSE Cb=[] 
%
% SNR    signal to noise ratio in dBs
% Ms     constellation size
% cnstl_type    type of constellation; PAM=1, QAM=2 or VSB=3  
% constellation constellation; PAM, QAM or VSB  
% csig   power of original (not unit norm) constellation
% 
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% EQUALIZER PARAMETERS %
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% f     forward equalizer coefficients, either baud- or fractionally-spaced
% Nf    length of f
% fa    for FSE even baud-spaced equalizer coefficients, fa=f(2:2:Nf); 
%       for BSE fa=[] 
% fb    for FSE odd baud-spaced equalizer coefficients fb=f(1:2:Nf);
%       for BSE fb=[] 
%
% F     frequency response of f
% Fa    for FSE frequency response of fa; for BSE Fa=[]  
% Fb    for FSE frequency response of fb; for BSE Fb=[] 
% 
% h     baud-spaced channel-forward equalizer combination; 
%       for BSE h=c*f; for FSE h=ca*fa+cb*fb
% Nh    length of h
% H     frequency response of H
% q     global channel-forward equalizer-feedback equalizer combo 
% Q     frequency response of 
%       global channel-forward equalizer-feedback equalizer combo 
%
% d     DFE feedback filter coefficients, baud-spaced
% Nd    length of d
% dd    zero-padded DFE feedback filter, matching length of channel-equalizer
%       response, i.e. dd=[0 ... 0 0  d 0 ... 0]
%                       h=[x ... x 1 -d x ... x]
% D     frequency response of D 
% DD    frequency response of DD 
%
% delay     desired cursor delay, single value or range of values;
%           delay=-1 when matching maximum channel tap
%           delay=-2 when optimum delay is to be found
% pdelay    processing delay (time taken to make a symbol decision)
%
% spacing   for BSE spacing=1; for FSE spacing=1/2
% Nfd       total number of parameters Nfd=Nf+Nd to search over for
%           optmial MSE design     
% bias      bias=0 for no bias, so MMSE design has constraint h(delay)=1 
%           bias=1 for no constraints on MMSE design 
%
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% ADAPTATION PARAMETERS %
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% f0    forward equalizer initialization 
% d0    feedback equalizer initialization 
%
% muf   step-size for updates of forward equalizer (training & blind modes) 
% mud   step-size for updates of feedback equalizer (trainign & blind modes)
%
% Lsim       length of simulation in terms of symbols transmitted
% alg1       training algorithm (LMS=1, or none=2) 
% alg2       blind algorithm (DD=2, CMA=3, or none=2) 
% structure  linear or nonlinear (decision feedback) structures LE=1, DFE=2
% data       type of data for adaptation 
%            (simulation=1, simulation loops=2, HDTV=3, custom=4, from file=5)
% regfilt    choice of regressor filtering (1) or not (0)
%
% fL      final forward equalizer f(Lsim) 
% faL     for BSE, final forward filter odd coefficients fa(Lsim) 
% fbL     for BSE, final forward filter even coefficients fa(Lsim) 
%
% FL      frequency response of FL
% FaL     frequency response of faL
% FbL     frequency response of fbL
%
% phi     phase offset between equalizer estimates and actual symbols
%
% hL      final channel-forward equalizer combination h(Lsim)
% qL      global channel-forward equalizer-feedback equalizer combo 
% deltaL  channel-forward equalizer cursor estimate (maximum tap of combo)
%         (known for LMS, deltaL=delta)
% HL      frequency response of hL
%
% dL      final feedback equalizer d(Lsim) 
% ddL     final feedback equalizer dd(Lsim) 
% DL      frequency response of dL
% DDL     frequency response of ddL
%
% alpha   excess bandwidth (0<alpha<=1) of sqrt. raised cosine
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% CALCULATED QUANTITIES %
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% 
% mmse  MSE of optimum receiver
% delta cursor delay of optimum receiver
% MSE   MSE over several parameterizations
% SER   probability of symbol estimation error for a single receiver
%       over range of SNRs 
% 
% res     shoft decision errors from error-propagation simuation
% hard    hard decision errors from error-propagation simulation
% source  source symbols from error-propagation simulation 
% soft    soft decisions from error-propagation simulation
% dec     decisions from error-propagation simulation 
% noise   channel noise from error-propagation simulation
%         for BSE, baud-spaced sequence; 
%         for FSE, 2-d vector baud-spaced sequence
% cnoise  channel noise filtered by forward equalizer 
% SEREP   SER computed from error propagation simulation
%
% acluster adaptation soft output (for cluster plot)
% ef       adaptation update error for forward equalizer  
% ed       adaptation update error for feedback equalizer  
% cv       adaptation cluster variance (averaged over last 200 symbols)
%%%%%%%%%%%%%%%%
% DECLARATIONS %
%%%%%%%%%%%%%%%%
% channel parameters
global  c Nc ca cb C Ca Cb SNR Ms cnstl_type constellation csig; 

% equalizer parameters
global f Nf fa fb F Fa Fb h Nh H q Q d Nd dd D DD...
       delay pdelay spacing Nfd bias; 

% adaptation parameters
global f0 d0 muf mud Lsim alg1 alg2 structure regfilt data...
       fL faL fbL FL FaL FbL phi  hL HL qL QL dL ddL DL DDL...
       fhist fahist fbhist dhist alpha;

% calculated quantities 
global  delta deltaL mmse MSE SER res hard source dec soft noise cnoise...
        SEREP acluster ef ed cv;