雷达方程

或

Pt为发射峰值功率，G为天线增益，lamda为载波波长，sigma为目标RCS,K为玻尔兹曼常数，Ts为以热力学温度为单位的有效噪声温度，B为带宽，L 为雷达损耗，F为噪声系数，R为雷达与目标间距离。

function [snr] = radar_eq(pt, freq, g, sigma, b, nf, loss, range)
% This program implements Eq. (1.63)
c = 3.0e+8; % speed of light
lambda = c / freq; % wavelength
p_peak = 10*log10(pt); % convert peak power to dB
lambda_sqdb = 10*log10(lambda^2); % compute wavelength square in dB
sigmadb = 10*log10(sigma); % convert sigma to dB
four_pi_cub = 10*log10((4.0 * pi)^3); % (4pi)^3 in dB
k_db = 10*log10(1.38e-23); % Boltzman's constant in dB
to_db = 10*log10(290); % noise temp. in dB
b_db = 10*log10(b); % bandwidth in dB
range_pwr4_db = 10*log10(range.^4); % vector of target range^4 in dB
% Implement Equation (1.63)
num = p_peak + g + g + lambda_sqdb + sigmadb;
den = four_pi_cub + k_db + to_db + b_db + nf + loss + range_pwr4_db;
snr = num - den;
return

 
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