repjam.m

此程序给出了不同情况的雷达距离测量仿真平台

% Repeater Jamming Effects
%---------------------------------------------
% Clear Old Variables
clear,clc,clf;

Rmin=.1; Rmax=500;      %  km

% Define Rtar(km) from Rmin to Rmax

Rtar=Rmin:.1:Rmax;      % .1 km steps

% Radar and Target Parameters

Pt=1e6;                 % w
Gt=10^(37/10);
Gr=10^(37/10);
sigma=5;                % sq m
wl=.1;                  % m
Lr=10^(10/10);
Gsl=10^(10/10);	      % dbi (Near-In Sidelobes)     

% Calculate Target Power Received at Radar

Pr=(Pt*Gr^2*sigma*wl^2)./((4*pi)^3*Lr*(Rtar*10^3).^4);
Prdbm=30+10*log10(Pr);

% Jammer Related Parameters

Pjsat=100;             % w
Gjr=10^(10/10);
Gjt=10^(10/10);
Lp=10^(3/10); 	        % Polarization Loss	
Beta=1;		           % Choping Loss		     
Lj=10^(7/10);
effrcs=10*sigma;       % Effective RCS
		
% Calculate Power Received by Jammer

Pjr=Pt*Gt*wl^2*Gjr./((4*pi*Rtar*10^3).^2*Lp);
Pjrdbm=30+10*log10(Pjr);

% Calculate Repeater Gain

Grep=4*pi*effrcs*(Lp^2)/((wl^2)*Beta^2);

% Calculate Repeaters Electronic Gain

Ge=Grep/(Gjr*Gjt);

% Calculate Jammer Power

Pj=Pjr*Ge;
for i=1:length(Rtar);
   if Pj(i)>Pjsat;Pj(i)=Pjsat;end;
end;

% Calculate Jam Power at Radar Receiver

Prj=Pj*Gjt*Gr*wl^2./((4*pi*Rtar*10^3).^2*Lp);
Prjdbm=30+10*log10(Prj);

% Calculate Sidelobe Jam Power at Radar

Pjrsl=Pjr*Gsl/Gt;
Pjsl=Pjrsl*Ge;
for i=1:length(Rtar);
  if Pjsl(i)>Pjsat;Pjsl(i)=Pjsat;end;
end;
Prjsl=Pjsl*Gjt*Gsl*wl^2./((4*pi*Rtar*10^3).^2*Lp); 
Prjsldbm=30+10*log10(Prjsl);

% Plotting Received Target and Jammer Signals

semilogx(Rtar,Prdbm,Rtar,Pjrdbm,Rtar,Prjdbm,Rtar,Prjsldbm);
ylabel('Received Signal (dbm)');
xlabel('Range (km)');grid;
title('REPEATER JAMMING AND TARGET SIGNALS AT RADAR');
axis([.1,1000,-100,50]);
text(2,35,'Repeater Input Signal');
text(20,-40,'Main Lobe Repeater Jammer');
text(.12,-75,'Side Lobe Repeater Jammer');
text(.4,10,'Main Lobe Skin Return');
text(6,-20,'Saturation');
text(.3,-7,'J/S=1');