www.pudn.com > programradarsystemdisign.zip > fig1_12.m

% Use this program to reproduce Fig. 1.12 of text. 
close all 
clear all 
pt = 1.5e+6; % peak power in Watts 
freq = 5.6e+9; % radar operating frequency in Hz 
g = 45.0; % antenna gain in dB 
sigma = 0.1; % radar cross section in m squared 
te = 290.0; % effective noise temperature in Kelvins 
b = 5.0e+6; % radar operating bandwidth in Hz 
nf = 3.0; %noise figure in dB 
loss = 6.0; % radar losses in dB 
range = linspace(25e3,165e3,1000); % range to target from 25 Km 165 Km, 1000 points 
snr1 = radar_eq(pt, freq, g, sigma, te, b, nf, loss, range); 
snr2 = radar_eq(pt, freq, g, sigma/10, te, b, nf, loss, range); 
snr3 = radar_eq(pt, freq, g, sigma*10, te, b, nf, loss, range); 
% plot SNR versus range 
figure(1) 
rangekm  = range ./ 1000; 
plot(rangekm,snr3,'k',rangekm,snr1,'k -.',rangekm,snr2,'k:') 
grid 
legend('\sigma = 0 dBsm','\sigma = -10dBsm','\sigma = -20 dBsm') 
xlabel ('Detection range - Km'); 
ylabel ('SNR - dB'); 
snr1 = radar_eq(pt, freq, g, sigma, te, b, nf, loss, range); 
snr2 = radar_eq(pt*.4, freq, g, sigma, te, b, nf, loss, range); 
snr3 = radar_eq(pt*1.8, freq, g, sigma, te, b, nf, loss, range); 
figure (2) 
plot(rangekm,snr3,'k',rangekm,snr1,'k -.',rangekm,snr2,'k:') 
grid 
legend('Pt = 2.16 MW','Pt = 1.5 MW','Pt = 0.6 MW') 
xlabel ('Detection range - Km'); 
ylabel ('SNR - dB'); 
 
 
 
% % Use this program to reproduce Fig. 1.27 of text. 
% close all 
% clear all 
% pt = 874.32e3; % peak power in Watts 
% freq = 3e+9; % radar operating frequency in Hz 
% g = 34.50; % antenna gain in dB 
% sigmam = 0.5; % missile RCS m squared 
% sigmaa = 4; % missile RCS m squared 
% te = 290.0; % effective noise temperature in Kelvins 
% b = 1.0e+6; % radar operating bandwidth in Hz 
% nf = 6.0; %noise figure in dB 
% loss = 8.0; % radar losses in dB 
% range = linspace(2e3,150e3,1000); % range to target from 25 Km 165 Km, 1000 points 
% snrm = radar_eq(pt, freq, g, sigmam, te, b, nf, loss, range); 
% snra = radar_eq(pt, freq, g, sigmaa, te, b, nf, loss, range); 
% % plot SNR versus range 
% figure(1) 
% rangekm  = range ./ 1000; 
% plot(rangekm,snrm,'k',rangekm,snra,'k -.') 
% grid 
% legend('Missile','Aircraft') 
% xlabel ('Detection range - Km'); 
% ylabel ('Single pulse SNR - dB'); 
%