sigsplitdim.m

阵列信号处理的工具箱

function sigOut = sigsplitdim(sigIn, splitDim, splitLen, newDim)

%SIGSPLITDIM Splits a dimension in a radar signal into two dimensions.
%
%--------
%Synopsis:
%  sigOut = sigsplitdim(sigIn, splitDim, splitLen, newDim)
%
%Description:
%  Splits a dimension in a radar signal into two dimensions.
%  This is useful, for example, when dividing the pulses (dimension 1) of a
%  radar signal into groups (e.g. CPIs, dimension  5) where each group can
%  be used as a snapshot for the target and interference estimation (via the 
%  space-time correlation matrix).
%
%Output and Input:
%  sigOut  (RxRadarSigT) : Radar signal after dimension split.
%  sigIn   (RxRadarSigT) : Radar signal before  dimension split.
%  splitDim (IntScalarT): The index of the dimension to split into two.
%  splitLen (IntScalarT): The length of the "splitDim" after the split.
%  newDim (IntScalarT): The index of the new dimension. The size of this 
%    dimension before the split must be one.
%
%--------
%Notations:
%  Data type names are shown in parentheses and they start with a capital
%  letter and end with a capital T. Data type definitions can be found in [1]
%  or by "help dbtdata".
%  [D] = This parameter can be omitted and then a default value is used.
%  When the [D]-input parameter is not the last used in the call, it must be
%  given the value [], i.e. an empty matrix.
%  ... = There can be more parameters. They are explained under respective
%  metod or choice.
%
%Examples:
%  s = RxRadarSigT;
%  s.signals = ones([4 6 8 1 1]);
%  s2 = sigsplitdim(s,1,2,4);
%  size(s2.signals)
%
%  ans = 
%        2 6 8 2 
%
%Software Quality:
%  (About what is done to ascertain software quality. What tests are done.)
%  This function has been tested by test 103 in the test script "tdbt.m".
%
%Known Bugs:
%  Maybe the updating of the fields "waveform", "pulIx", "ranIx" etc. in
%  the output radar signal is incorrect.
%
%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.
%
%See Also:
%  sigsize msigmat2 sigsubix

%   *  DBT, A Matlab Toolbox for Radar Signal Processing  *
% (c) FOA 1994-2000. See the file dbtright.m for copyright notice.
%
%  Start        : 991016 Svante Bj鰎klund (svabj).
%  Latest change: $Date: 2000/10/16 15:21:48 $ $Author: svabj $.
%  $Revision: 1.5 $
% *****************************************************************************


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

arginNo=4;
if (nargin < arginNo)
  error('DBT-Error: To few input parameters.')
end
arginNo = arginNo +1;


% ****************** Add missing input parameters ******************
%if (nargin < arginNo)
%  method = [];
%end


% ****************** Default values ******************
%if isempty(method)
%  method = [];
%end%if


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

chkdtype(sigIn, 'RxRadarSigT')
chkdtype(splitDim, 'IntScalarT')
chkdtype(splitLen, 'IntScalarT')
chkdtype(newDim, 'IntScalarT')

sizeSpec = sizem(sigIn.signals);
if (rem(sizeSpec(splitDim), splitLen) ~= 0)
  error('DBT-Error: Size of splitDim must be multible of splitLen.')
end%if
if (sizeSpec(newDim) ~= 1)
  dbterror('The size of the new dimension must be one.')
end%if


% ****************** Create output variable ******************

sigOut = sigIn;


% ----------------------------------------------------------------------- %
% RxRadarSigT: Radar signals.
% ----------------------------------------------------------------------- %


  % ****************** Signal size ******************

  noPulses = sizeSpec(1);	
  noRanges = sizeSpec(2);
  noChannels = sizeSpec(3);
  noExtras = sizeSpec(4);
  noCPIs   = sizeSpec(5);
  noTrials = sizeSpec(6);

  maxDim = 6;

  % ****************** Permute Order 1 ******************

  permuteOrder1 = 1:maxDim;
  permuteOrder1 = swap(permuteOrder1, splitDim, newDim-1);
  sigMat = permute(sigIn.signals, permuteOrder1);

  % ****************** Reshape sizes ******************

  ss = sizem(sigMat);
  newDimLen = fix(ss(newDim-1) / splitLen);
  reshapeSizes = ([ss(1:newDim-2), splitLen, newDimLen, ss((newDim+1):maxDim)]);
  sigMat = reshape(sigMat, reshapeSizes);


  % ****************** Permute Order 2 ******************

  sigOut.signals = permute(sigMat, permuteOrder1);


  % ****************** Update size information ******************

  ss = sizem(sigOut.signals);
  sigOut.waveform.noPulses = ss(1);
  sigOut.waveform.noCPI = ss(5);
  if ((splitDim == 2) | (newDim == 2))
    dbtwarning('The contents of "sigOut.waveform" will be incorrect.')
      % Because "waveform.noRangeBins" is not updated. Should it be updated?
  end%if
  if isfield(sigIn,'spaIx')
    sigOut.pulIx = sigIn.pulIx(1:ss(1));
    sigOut.ranIx = sigIn.ranIx(1:ss(2));
    sigOut.spaIx = sigIn.spaIx(1:ss(3));
  end%if


%endfunction sigsplitdim



function vectorOut = swap(vectorIn, index1, index2)
  tmp = vectorIn(index1);
  vectorIn(index1) = vectorIn(index2);
  vectorIn(index2) = tmp;
  vectorOut = vectorIn;
%endfunction swap