signalgen.m

rang doppler imaging and motion compensation中的源代码

   function Umnnoise = signalgen(radarp,position,motionp,sposition,db,sv)
%
%	Generates radar echo transfer function given radar parameters.
%
%  radarp is radar parameter composed as
%     radarp(1)=bandwidth
%     radarp(2)=carrier frequency
%     radarp(3)=pulse repetion frequency
%     radarp(4)=number of bursts
%     radarp(5)=number of pulses
%     radarp(6)=speed of light.
%
%  position is position of scatterers in x-y plane.
%
%  motionp is target motion parameter defined as
%     motionp(1)=velocity of translational motion
%     motionp(2)=acceleration of translational motion
%     motionp(3)=jerk of translational motion
%     motionp(4)=angular velocity
%     motionp(5)=angular acceleration.
%
%  sposition is position of target referenced to LOS
%     sposition(1)=rotated position using radian
%     sposition(2)=initial range.
%
%  db is noise in db.
%
%  sv is 'saved' or 'none'.
%  'saved' saves generated data to Adata.mat.
%

      bandw=radarp(1);
      carf=radarp(2);
      prf=radarp(3);
      mm=radarp(4);
      nn=radarp(5);
      cc=radarp(6);

      vnot=motionp(1);   
      anot=motionp(2);    
      jnot=motionp(3);
      rv=motionp(4);
      ra=motionp(5);

      theta=sposition(1);
      rangn=sposition(2);

      delf=bandw/(nn-1);
      xposition=position(:,1);
      yposition=position(:,2);
      thetaxis=pi/2+theta;
      numscat=size(position,1);

      ddb=10^(db/10);
      deviat=sqrt(1/ddb);
      randn('state',sum(100*clock));
      rgauss=randn(mm,nn);
      rgaus=rgauss.*deviat;
      randn('state',sum(100*clock));
      igauss=randn(mm,nn);
      igaus=igauss.*deviat;

      fm=tranfreqm(mm,nn,carf,bandw);
 
      tt=timegen(prf,mm,nn);
      tta=tt.^2;
      ttj=tt.^3;

      rmn=rangn+vnot*tt+0.5*anot*tta+1/6*jnot*ttj;
      thetamn=thetaxis+rv*tt+0.5*ra*tta;
      pmn=2*(fm/cc).*sin(thetamn);
      qmn=2*(fm/cc).*cos(thetamn);
      Hmn=0;
      for num=1:numscat
      hmn=exp(i*2*pi*(pmn.*xposition(num)+qmn.*yposition(num)));
      Hmn=Hmn+hmn;
      end
      Umn=exp(i*4*pi/cc*fm.*rmn).*Hmn;

      Ichannel=real(Umn)+rgaus;
      Qchannel=imag(Umn)+igaus;
      Umnnoise=Ichannel+i*Qchannel;

      if strcmp(sv,'saved') == 1
      save Adata.mat Umnnoise;
      end