wscordbt.m

阵列信号处理的工具箱

function scmp=wscordbt(s, wstypDummy, coupFlag, Ccmpmet, wcmatDummy, wnfcmp, wctabAnglesDummy, doas)

%WSCORDBT Corrects steering/test vectors for near field, coupling and gain/phase.
%
%--------
%Synopsis:
%  scmp=wscordbt(s, wstypDummy, coupFlag, Ccmpmet, wcmatDummy, wnfcmp,  ...
%    wctabAnglesDummy, doas)
%
%Description:
%  Corrects steering/test vectors for near field, coupling and gain/phase.
%  scmp = inv(diag(wcmat)) * inv(Ccmp.') * inv(wnfcmp) * s
%  For more information on the calibrations and corrections, see [2,3].
%
%  (Korrigerar styr/test-vektor utgaaende fraan kaenda korrektionsmatriser
%  s=diag(wcmat)(-1)*Ccmp(T-1)*wnfcmp(-1)*s0
%  daer s och scmp aer kolumnvektorer, dim [1,nel] eller [nang,nel] )
%
%  The calibration compensation information is stored in global variables
%  by the function "setcal1".
%  This file is an adaption to DBT of Lars Petterssons file wscorr.m.
%  This function is called by spastemat.
%
%Output and Input:
%  scmp (CxMatrixT): Corrected steering/test matrix.
%  s (CxMatrixT): Not corrected steering/test matrix.
%  wstypDummy: Not used.
%  coupFlag: An empty matrix means that coupling compensation will not be made.
%  Ccmpmet (StringT): Type of coupling calibration. Gain and phase corrections
%    are also performed.
%    = 'Ccmp': Use decoupling matrix.
%    = 'wctab': Use table of corrections for different directions. An
%      interpolation will be used to find the "right" direction.
%    = 'wcmedel': Use the "wcmedel" method, see [2].
%    = 'nocomp': No coupling calibration and no gain and phase correction.
%  wcmatDummy: Not used. Instead a global variable "wcmat" is used.
%  wnfcmp: Near field correction factors, as delivered by the function
%    "eincdbt". An empty matrix means that near field correction will not
%    be made.
%  wctabAnglesDummy: Not used.
%  doas (): The directions to use when looking up in the table "wctab".
%
%Global Variables:
%  Ccmp (CxMatrixT): Decoupling matrix. Created in "setcal1".
%  wctab (CxMatrixT): Table of corrections for different directions.
%    Created in "setcal1".
%  phitab: Created in "setcal1".
%  wcmedel (CxMatrix): Correction vector for the "wcmedel" method.
%    Created in "setcal1".
%  wcmat (CxMatrix): Correction vector for channel erros or drift since
%    last calibration of coupling (Ccmp or wctab). This correction is always
%    done unless the global variable "wcmat" is an empty matrix.
%    Created in "setcal1".
%
%--------
%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.
%
%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]: Pettersson L.: "講ersiktlig beskrivning av m鋞dataanalysprogram f鰎
%    digital experimentantenn", FOA-D--96-00226-3.2--SE, FOA February 1996.
%  [3]: Pettersson L., Danestig M., Sj鰏tr鰉 U.: "An Experimental S-Band
%    Digital Beamforming Antenna", IEEE AES Systems Magazine, November 1997,
%    p.19-26.
%
%See Also:
%  spastemat, eincdbt, vcorrdbt, setcal1, sigcomp2

%
%   *  DBT, A Matlab Toolbox for Radar Signal Processing  *
% (c) FOA 1994-2000. See the file dbtright.m for copyright notice.
%
%  Start        : 9xxxxx Lars Pettersson (larpet).
%  Latest change: $Date: 2001/08/31 15:04:30 $ $Author: svabj $.
%  $Revision: 1.13 $
% *****************************************************************************

%disp('Compensate steering vectors.')


global Ccmp wctab phitab wcmedel wcmat

[nfang,nelnf]=size(wnfcmp);

  % Korrigera f鰎st naerfaeltseffekter.
  % Notera att om wnfcmp==[] saa g鰎s ingen naerfaeltskorrigering.
  if ~isempty(wnfcmp)		% This test is unnecessary because the
				% nested if-statement checks the same.
    if nfang==1
      s=diag(1./wnfcmp)*s;
    elseif nfang > 1
      s=1./wnfcmp.'.*s;
    end
  end%if

  % Korrigera sedan for koppling.
  if ~isempty(coupFlag)
    if strcmp(Ccmpmet,'Ccmp')
      s=inv(Ccmp.')*s;
    elseif strcmp(Ccmpmet,'wcmedel')
      s=diag(1./wcmedel)*s;
    elseif (strcmp(Ccmpmet,'wctab') & size(wctab,1)==1)
      s=diag(1./wctab)*s;
    elseif strcmp(Ccmpmet,'wctab') & size(wctab,2)==size(s,1)
      % Size check changed.
      s=1./(interp1(phitab,wctab,doas(1,:)')).'.*s;
    elseif strcmp(Ccmpmet,'nocomp')
      % Do nothing
    else
      error('DBT-Error: Felaktigt Ccmpmet i wscorr');
    end%if
  end%if

  if (~strcmp(Ccmpmet,'nocomp'))
    % Korrigera sedan foer kanalfel, eller drift sedan coupcal
    if ~isempty(wcmat)
      s=diag(1./wcmat)*s;
    end
  end%if

  scmp=s;