dbtex23.m

雷达信号处理、或阵列信号处理中能够用上的重要的matlab工具箱——阵列信号处理工具箱

function dbtex23

%DBTEX23 An example of doppler filtering of radar signals.

%
%   *  DBT, A Matlab Toolbox for Radar Signal Processing  *
%  (c) FOA 1994-2000. See the file dbtright.m for copyright notice.
%  Start        : 991012 Svante Bj鰎klund (svabj).
%  Latest change: $Date: 2000/10/16 18:56:32 $ $Author: svabj $.
%  $Revision: 1.1 $
%*****************************************************************************


% ----------------------------------------------------------------------- %
% Definition of the antenna.
% ----------------------------------------------------------------------- %

lambda  = 0.03;             % wavelength.
D   = 0.45*lambda;          % Element separation.
%noChannels   = 12;          % Number of digital antenna channels.
noChannels   = 48;          % Number of digital antenna channels.
recAnt = defant('isotropULA',[noChannels,D]);


% ----------------------------------------------------------------------- %
% Definition of the waveform.
% ----------------------------------------------------------------------- %

%pri = 1e-3;
pri = 1e-4;
noPulses = 24;
noCPI = 1;
sampleTime = 1e-6;   % SubPulseLength [s]
noRangeBins = round(pri / sampleTime);
noRangeBins = 100;
pModulation = getmod('barker','13');  % Barker-13 has sidelobes 1/13 of the main peak.
%pModulation =[];
waveform = defwave(lambda, noRangeBins, noPulses, pModulation, sampleTime);


% ----------------------------------------------------------------------- %
% Definition of the sources.
% ----------------------------------------------------------------------- %

%target = deftarget(trgType, trgPower, trgRange, trgDOA, trgVel);
trg1 = deftarget('swerling0', 10^1.2, 6000, [d2r(25); 0], 20);
trg2 = deftarget('swerling0', 10^0.6, 1000, [d2r(18); 0], -30);
trg3 = deftarget('swerling0', 10^0.8, 730000, [d2r(-3); 0], 5);

%noiseSrc = defnoise(noiseType, noisePower);
noiseSrc1 = defnoise('Gaussian', 0.3, eye(noChannels));

%clutterdef = defclutter(clutterType, clutterTypeParam, clutterPower, clutterPatchDOAs, transAnt)
%clutterSrc1 = defclutter('MIT-LCE', {6000 4 50}, 10, d2r(-30):0.01:d2r(30));

%srcDef = defsources(srcList, trgCorrMx)
%sources = defsources({trg1 trg2 trg3}, eye(3));
sources = defsources({trg1 trg2 trg3 noiseSrc1}, eye(3));
%sources = defsources({trg2 noiseSrc1}, eye(1));
%sources = defsources({trg1 trg2 trg3 noiseSrc1 clutterSrc1}, eye(3));


% ----------------------------------------------------------------------- %
% Simulation of radar signals.
% ----------------------------------------------------------------------- %

radarSig = simradarsig(recAnt, sources, waveform, pri);


% ----------------------------------------------------------------------- %
% Signal processing and plotting.
% ----------------------------------------------------------------------- %

%----  Pulse compression ----

radarSig=pulscomp(radarSig,pModulation);

%ranAxis = (0:99)*150;
ranAxis = (1:80)*150;


%----  Beamforming : Conventional beamforming ----

%spaAxis = d2r(-10:0.5:40);
spaAxis = [];

sigFinal = beamform(radarSig,spaAxis,[],'taylor',50);
spaAxis = r2d(sigFinal.doaPos);


%----  Plotting the signal  ----
sigFinal;
figure
%13:25
sigplot2(sigFinal,1,50:60,':',{...
  'spaAxis', spaAxis, ...
  'scaleType', 'lin'});
  %'ranAxis', ranAxis, ...
%ylabel('Ranges [m]')
xlabel('Direction [degrees]')
title('Conventional beamforming, 50 dB Taylor')
%shading('interp')



dopScaleType = 'lin';
noFreqsOut = 96;
prf = 1/pri;
%----  Doppler filtering : Conventional filtering ----

pulAxis = genfreqaxis(0,prf,noFreqsOut).';

sigFinal = pulfilt(sigFinal, 'cbf', {radarSig.antenna, radarSig.waveform},...
  [], pulAxis);
spaAxis = r2d(sigFinal.doaPos);
%pulAxis = sigFinal.freqPos;
pulAxis = sigFinal.freqPos * lambda / 2; % Radial speed.


%----  Plotting the signal  ----
figure
% Targets at ranges 19, 53 range bins.
sigplot2(sigFinal,':',53,':',{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
xlabel('Direction [degrees]')
title('Conventional Doppler filtering, with beamforming')
%shading('interp')


%----  Doppler filtering : Conventional filtering , without beamforming ----

pulAxis = genfreqaxis(0,prf,noFreqsOut).';

sigFinal2 = pulfilt(radarSig, 'cbf', {radarSig.antenna, radarSig.waveform},...
  [], pulAxis);
spaAxis = r2d(sigFinal2.doaPos);
%pulAxis = sigFinal2.freqPos;
pulAxis = sigFinal2.freqPos * lambda / 2; % Radial speed.

%----  Plotting the signal  ----
figure
sigplot2(sigFinal2,':',':',1,{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
%xlabel('Direction [degrees]')
title('Conventional Doppler filtering, without beamforming')
%shading('interp')


%----  Doppler filtering : FFT , without beamforming ----

pulAxis = genfreqaxis(0,prf,noFreqsOut).';

sigFinal2 = pulfilt(radarSig, 'fft', {radarSig.antenna, radarSig.waveform},...
  [], [],[],[],[],96);
spaAxis = r2d(sigFinal2.doaPos);
%pulAxis = sigFinal2.freqPos;
pulAxis = sigFinal2.freqPos * lambda / 2;  % Radial speed.

%----  Plotting the signal  ----
figure
sigplot2(sigFinal2,':',':',1,{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
%xlabel('Direction [degrees]')
title('FFT Doppler filtering')
%shading('interp')


%----  Doppler filtering : Capon , without beamforming ----

pulAxis = genfreqaxis(0,prf,384).';

sigFinal2 = pulfilt(radarSig, {
  'method', 'capon',...
  'model', {radarSig.antenna, radarSig.waveform},...
  'freqChoice' pulAxis,...
  'sampleDim', 3});
spaAxis = r2d(sigFinal2.doaPos);
%pulAxis = sigFinal2.freqPos;
pulAxis = sigFinal2.freqPos * lambda / 2; % Radial speed.

%----  Plotting the signal  ----
figure
sigplot2(sigFinal2,':',':',1,{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
%xlabel('Direction [degrees]')
title('Capon Doppler filtering, without beamforming')
%shading('interp')


%----  Doppler filtering : MUSIC , without beamforming ----
if (0)

pulAxis = genfreqaxis(0,prf,noFreqsOut).';

sigFinal2 = pulfilt(radarSig, 'music', {radarSig.antenna, radarSig.waveform},...
  [], pulAxis);
spaAxis = r2d(sigFinal2.doaPos);
%pulAxis = sigFinal2.freqPos;
pulAxis = sigFinal2.freqPos * lambda / 2; % Radial speed.

%----  Plotting the signal  ----
figure
sigplot2(sigFinal2,':',':',1,{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
%xlabel('Direction [degrees]')
title('Capon Doppler filtering, without beamforming')
%shading('interp')

end%if (0)


%----  Doppler filtering : dfb2 , without beamforming ----

PRI = radarSig.waveform.noRangeBins * radarSig.waveform.sampleTime
PRF = 1/PRI;


[sigFinal2, vd] = dfb2(radarSig,PRF,noFreqsOut);
spaAxis = r2d(sigFinal2.doaPos);
%pulAxis = sigFinal2.freqPos;
pulAxis = vd;

%----  Plotting the signal  ----
sigFinal2;
figure
sigplot2(sigFinal2,':',':',1,{...
  'spaAxis', spaAxis, ...
  'pulAxis', pulAxis, ...
  'scaleType', dopScaleType});
  %'ranAxis', ranAxis, ...
%ylabel('Doppler Frequency [Hz]')
ylabel('Radial speed [m/s]')
%xlabel('Direction [degrees]')
title('Doppler filtering with dfb2')
%shading('interp')



%End Of File