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Sigmaref = 0.1; % ref RCS in m^2
Lossp = 2; % processing loss in dB
lossp = 10^(Lossp/10);
% Enter desired value
tau = tau_ref;
R = 120e3;
rangeratio = (Rref / R)^4;
Sigma = 0.2;
% Implement Eq. (1.60)
snr = snrref * (tau / tau_ref) * (1. / lossp) * ...
(Sigma / Sigmaref) * rangeratio;
snr = 10*log10(snr)
Listing 1.5. MATLAB Function Ðpower_aperture.mÑ
function PAP =
power_aperture(snr,tsc,sigma,range,te,nf,loss,az_angle,el_
angle)
% This program implements Eq. (1.67)
Tsc = 10*log10(tsc); % convert Tsc into dB
Sigma = 10*log10(sigma); % convert sigma to dB
four_pi = 10*log10(4.0 * pi); % (4pi) in dB
k_db = 10*log10(1.38e-23); % Boltzman's constant in dB
Te = 10*log10(te); % noise temp. in dB
range_pwr4_db = 10*log10(range.^4); % target range^4 in dB
omega = az_angle * el_angle / (57.296)^2; % compute search volume in stera-
dians
Omega = 10*log10(omega) % search volume in dB
% implement Eq. (1.67)
PAP = snr + four_pi + k_db + Te + nf + loss + range_pwr4_db + Omega ...
- Sigma - Tsc;
return
Listing 1.6. MATLAB Program Ðfig1_16.mÑ
% Use this program to reproduce
Fig. 1.16
of text.
close all
clear all
tsc = 2.5; % Scan time is 2.5 seconds
sigma = 0.1; % radar cross section in m squared
te = 900.0; % effective noise temperature in Kelvins
snr = 15; % desired SNR in dB
nf = 6.0; %noise figure in dB
loss = 7.0; % radar losses in dB
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