pantpat2.m

阵列信号处理的工具箱

function spect = pantpat2(antenna, taperType, taperParam, smplPoints, doa0, plotopt, lambda)

% *****************************************************************************
%   *  DBT, A Matlab Toolbox for Radar Signal Processing  *
% (c) FOA 1994-2000. See the file dbtright.m for copyright notice.
%
% function  spect = pantpat2(antenna, taperType, taperParam, smplPoints,
%   doa0, plotopt, lambda)
%
% Plots the antenna pattern.
%
% This function uses conventional beamforming to do this. I this case the
% antenna pattern is the same as the electrical scan pattern.
% There are two possible antenna patterns for an array antennna, either with
% mechanical angle scan or electronical angle scan. The antenna patterns are
% generated by the same formula:
%   P(thetaMec, thetaEl) = abs(w(thetaEl)' * a(thetaMek))^2 ,
% where w(thetaEl) = taper*.a(thetaEl) = a(thetaEl)*diag(taper) is the
% weight vector and a(theta) is the steering vector. Depending on wich of
% thetaMec and thetaEl that is beeing varied while the other is held
% constant, the mechanical or the electrical pattern is generated.
% The function pantpat2 generates the electrical pattern.
%
% NOTE: This function pantpat2 is not tested.
%
% Parameter:   Data type:  Description:
% ----------   ----------  ------------
%  spect (DoaSpecT): Output DOA-spectrum. It is a quadratic measure of the
%    presence of sources in different directions.
% antenna   AntDefT
% taperType, taperParam    : See the function taper.
% smplPoints   Vector of DoaT : Angle grid on which the pattern will
%           be computed
% doa0      Vector of DoaT : Pointing direction of main array and
%             subarrays.
% plotopt
% lambda        RealScalarT     : Wavelength [m].

%
%  Start        : 961122 Svante Bj鰎klund (svabj).
%  Latest change: $Date: 2000/10/16 15:21:15 $ $Author: svabj $.
%  $Revision: 1.12 $
% *****************************************************************************

disp('Warning: The function pantpat2 is obsolete and will be removed. Use pantpat3 instead.')


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

arginNo=2;
if (nargin < arginNo)
  taperType = [];
end
arginNo = arginNo +1;
if (nargin < arginNo)
  taperParam = [];
end
arginNo = arginNo +1;
if (nargin < arginNo)
  smplPoints = [];
end
arginNo = arginNo +1;
if (nargin < arginNo)
  doa0 = [];
end
arginNo = arginNo +1;
if (nargin < arginNo)
  plotopt = [];
end
arginNo = arginNo +1;
if (nargin < arginNo)
  lambda = [];
end

% ****************** Default values ******************

if isempty(taperType)
  taperType = 'notaper';
end%if
if isempty(taperParam)
  taperParam = [];
end%if
if isempty(smplPoints)
  smplPoints = [];
end%if
if isempty(doa0)
  doa0 = 0;
end%if
if isempty(plotopt)
  plotopt = [];
end%if
if isempty(lambda)
  lambda = 1;
end%if



% ----------------------------------------------------------------------- %
% Parameters.
% ----------------------------------------------------------------------- %
T  = 2;        % Number of snapshots.

theta = doa0(1,1);      % Target angles. The number of targets is
            %  given by the number of target angles.
phi   = 0;        % Target angles.
SNR   = [10]';    % Signal to noise ratio in dB at each
            %  antenna element!?!
alpha = d2r([0])';      % Start phases of the target signals.
dalpha   = d2r([0])';      % A constant phase shift between snapshots.
            %  Means targets movements at constant velocity.
dist=Inf*ones(size(theta));   % Distances to the sources.

% ----------------------------------------------------------------------- %
% Commands.
% ----------------------------------------------------------------------- %

%lambda = antenna.lambda;

% Generate simulated received antenna signals.
sig = compsim4(antenna, lambda, T, 'const', [theta, phi, SNR, alpha, dalpha, dist], 'nonoise');

antennaType = antenna.antennaType;
if (strcmp(antennaType,'ULA'))
  beamWidth = lambda/(antenna.noElem*antenna.distElem);
  smplPos = -pi/2:(beamWidth/10):pi/2;
else
  smplPos = asin(-1:0.005:1);
end

% Estimate the DOA-spectrum with conventional beamforming.
spect = sdoaspc('cbf', sig, smplPos, taperType, taperParam);
spect.spectrumType = 'Antenna Pattern';

% Plot antenna pattern.
splot2(spect)
%splot2(spect,' s')