ecorrm.m

阵列信号处理的工具箱

%  ... = There can be more parameters. They are explained under respective
%  metod or choice.
%
%Examples:
%  ant = defant('isotropULA',[K,D,lambda]);
%  sig = compsim2(ant, 1, T, tgtModel, [theta, phi, SNR, alpha, dalpha, ...
%    dist, ones(size(theta,1))], 'rndn', eye(K));
%  R = ecorrm(sig,'spatsmooth',[],[],10);
%  splot2(sdoaspc('music',R1,[],MMu))
%
%Algoritm:
%
%Software Quality:
%  (About what is done to ascertain software quality. What tests are done.)
%
%Known Bugs:
%
%References:
%  [1]: Bj鰎klund S.: "DBT, A MATLAB Toolbox for Radar Signal Processing.
%    Reference Guide", FOA-D--9x-00xxx-408--SE, To be published.
%  [2]: Krim H., Viberg M.:"Two Decades of Array Signal Processing Research",
%    IEEE Signal Processing Magazine, July 1996, pp. 67-94.
%  [3]: Carlsson B.D.: "Covariance Estimation Errors and Diagonal Loading
%    in Adaptive Arrays", IEEE Trans. AES-24, No. 4, July 1988, pp. 397-401.
%  [4]: Ganz M.W., Moses R.L., Wilson S.L.: "Convergence of the SMI and the
%    Diagonally Loaded SMI Algorithms with Weak Interference", IEEE Trans.
%    AP-38, No. 3, March 1990, pp. 394-399.
%  [5]: Nickel U.: "Comparison of some criteria to determine the dimension
%    of the signal subspace for small sample size", Report No. 457, FGAN-FFM
%    1996, Germany, p. 13.
%
%See Also:
%  basecorrm, modcorrmkernel


%   *  DBT, A Matlab Toolbox for Radar Signal Processing  *
% (c) FOA 1994-2000. See the file dbtright.m for copyright notice.
% Test text \alpha = \beta/2
%
% Start        : 960924 Svante Bj鰎klund (svabj).
% Latest change: $Date: 2000/10/16 15:20:50 $ $Author: svabj $.
% $Revision: 1.39 $
% *****************************************************************************

%disp('ecorrm')

% ----------------------------------------------------------------------- %
% Handle input parameters
% ----------------------------------------------------------------------- %

if (nargin < 1)
  error('DBT-Error: To few input parameters.')
end

% ****************** Add missing input parameters ******************

if (nargin < 2)
  method = [];
end
if (nargin < 3)
  rangeIx = [];
end
if (nargin < 4)
  cpiIx = [];
end
if (nargin < 5)
  in5 = [];
end
if (nargin < 6)
  in6 = [];
end
if (nargin < 7)
  in7 = [];
end


% ****************** Default values ******************
if isempty(method)
  method = 'ml';
end%if
if isempty(rangeIx)
  rangeIx = 1;
end%if
if isempty(cpiIx)
  cpiIx = 1;
end%if

%fprintf('rangeIx=%d, cpiIx=%d\n',rangeIx, cpiIx);

% ****************** Error check input parameters ******************

chkdtype(inData, 'RxCompSigT', 'RxRadarSigT', 'RxCorrMatT')
chkdtype(method, 'StringT')


% ----------------------------------------------------------------------- %
% Preparation before the loops.
% ----------------------------------------------------------------------- %

% ****************** Create output variable if necessary. ******************

if (strcmp(inData.dataType,'RxCompSigT') | ...
    strcmp(inData.dataType,'RxRadarSigT'))
  sizeSig = sigsize(inData,[],'n');
  noChan = sizeSig(3);
  Rout = RxCorrMatT(zeros([noChan, noChan,length(rangeIx),1,length(cpiIx)]),...
    [], inData);
  sigField = inData.signals;
  ant = inData.antenna;			% Where is this used?
elseif (strcmp(inData.dataType,'RxCorrMatT'))
  if (inData.version < 4)
    %Convert to version 4.
    error('DBT-Error: Too old version of input parameter "inData".')
  else
    Rout = inData;
      % Copy output variable.
  end%if
else
  error('DBT-Error: Illegal datatype of input parameter "inData".')
end%if

% ----------------------------------------------------------------------- %
% Loops for several range gates and cpis.
% ----------------------------------------------------------------------- %

% ****************** Loops. ******************
changeAntFlag = 0;

for cpiLoop = 1:length(cpiIx)
for rangeLoop = 1:length(rangeIx)

% ----------------------------------------------------------------------- %
% Get a base estimate of the correlation matrix
% ----------------------------------------------------------------------- %

if (strcmp(inData.dataType,'RxCompSigT') | ...
    strcmp(inData.dataType,'RxRadarSigT'))

  X = (getm(sigField, ':',rangeIx(rangeLoop),':',1,cpiIx(cpiLoop))).';
  L = size(X,2);
  Rxx = 1/L * X*X';
    % Maximum Likelihood estimate
  
  %Should more fields be copied? All fields but "signals"? YES!
  %Rout = signals;
  %Rout.signals = [];  % Would be better to remove the field.
  %Rout.dataType = 'RxCorrMatT';
  %Rout.version = 3;
  %Rout.corrMat = Rxx;

  Rout.noSamples = L;
    % This assignment is not necessary to do in each loop.

elseif (strcmp(inData.dataType,'RxCorrMatT'))
  Rxx = inData.corrMat(:,:,rangeLoop, 1, cpiLoop);
    % Pick out fields from input parameters. 

elseif ~chkdtyph(inData,'CxMatrixT')
  % This choice can not be used yet.
  %disp('User selected samples as input.')
  error(['DBT-Error: The implementation is not finnished for this',...
    ' data type of input parameter "inData"'])
  if (0)
  L = size(X,2);
  Rxx = 1/L * X*X';
    % Maximum Likelihood estimate

  % ****************** Create an output variable. ******************
  % This should be done by the function "RxCorrMatT"!
  Rout.dataType = 'RxCorrMatT';
  Rout.version = 3;
  Rout.corrMat = Rxx;
  Rout.antenna = ant;  % We do not know the antenna definition.
  Rout.noSamples = L;
  % Here we can not copy any extra fields from a RxRadarSigT signal,
  % since we have no RxRadarSigT signal.
    % Use the contructor "RxCorrMatT" instead!
  end%if (0)
else
  error('DBT-Error: Illegal datatype of input parameter "inData".')
end%if


% ----------------------------------------------------------------------- %
% Methods for the modification of the estimate.
% ----------------------------------------------------------------------- %


[Rxx, T] = modcorrmkernel(Rxx, method, in5, in6, in7);
changeAntFlag = ~isempty(T);


% ----------------------------------------------------------------------- %
% Return data.
% ----------------------------------------------------------------------- %

infoStr = sprintf('ecorrm: cpiLoop = %d(%d), rangeLoop = %d(%d)\r',cpiLoop, ...
  length(cpiIx), rangeLoop,length(rangeIx));
dbtinfo(infoStr,1);

%if (size(Rout.corrMat,1) ~= size(Rxx,1))
  % It is assumed that the method
  % has changes the size already in the first execution of the loops.
if (changeAntFlag & (rangeLoop == 1) & (cpiLoop == 1))
  Rout.corrMat = zeros(size(Rxx,1),size(Rxx,2), size(Rout.corrMat,3),...
    size(Rout.corrMat,4), size(Rout.corrMat,5), size(Rout.corrMat,6), ...
    size(Rout.corrMat,7));
      % If the method has changed the size of the correlation matrix,
      % change the size of "Rout.corrMat". 
  Rout = setspatrans(Rout,T);
end%if

Rout.corrMat(:,:,rangeLoop, 1, cpiLoop) = Rxx;

end%for rangeLoop
end%for cpiLoop

dbtinfo('');	%New line.

Rout.ranIx = rangeIx;
Rout.cpiIx = cpiIx;
  % How to interpret these fields and input parameters when reducing
  % the data size more than once?


%endfunction ecorrm