雷达信号集锦（常规、相位编码、线性、非线性、噪声干扰（调幅、调频、调相））.zip

%传统基于逗留相位原理的窗函数反求法-NLFM信号 clear all;clc ;close all fs=100e6;%100Mhz fc=10e6;%10Mhz T=10e-6; B=20e6; N=T*fs; t=-T/2:1/fs:T/2-1/fs; f=(-N/2:N/2-1)*B/N; Tf=T*f/B+(0.426*T/pi).*sin(2*pi*f/B);%海明窗 % Tf=T*f/B+(T/(2*pi))*sin(2*pi*f/B);%汉宁窗 % Tf=T*f/B+((2*T)/(3*pi))*sin(2*pi*f/B)+(T/(12*pi))*sin(4*pi*f/B);%余弦四次方窗 figure(1) subplot(211) plot(f,Tf);grid on title('群时延函数Tf/f') xlabel('frequency/hz') ylabel('time/s') f_t=interp1(Tf,f,t,'spline'); %三次样条插值法 % [p,~,mu]=polyfit(Tf,f,20); %多项式拟合 % f_t=polyval(p,t,[],mu); subplot(212) plot(t,f_t); grid on ; title('时频函数f/Tf') xlabel('time/s') ylabel('frequency/hz') % te=t(1); sumi=0; %数值积分 for i=1:N % dt=t(i)-te; % te=t(i); f_t(i)=f_t(i)*(1/fs)+sumi; sumi=f_t(i); phi(i)=2*pi*f_t(i);%相位 end % phi=2*pi*f_t;%相位 s=exp(1j*phi);%S形NLFM信号 figure(2) subplot(211) plot(t,real(s)) title('NLFM基带信号实部'); subplot(212); plot(t,imag(s)); title('NLFM基带信号虚部'); figure(3) subplot(211); plot(t,phi); title('NLFM相位') S=fftshift(abs(fft(s))); subplot(212) plot(f,S);%NLFM频谱 title('NLFM信号频谱')