function signal=Creatnlfm(pulseLen,a1,a2,a3,amp,dt)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%signal=CreatNLFM(pulseLen,from,endpos,freq,pha,amp,k,dt)
%非線性調(diào)頻信號(hào)發(fā)生器
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
tin=1:pulseLen;
signal1=amp*cos(2*pi*(a1*1e6*tin*dt+a2*1e12*tin.^2*dt*dt+a3*1e16*tin.^3*dt*dt*dt));
signal2=amp*sin(2*pi*(a1*1e6*tin*dt+a2*1e12*tin.^2*dt*dt+a3*1e16*tin.^3*dt*dt*dt));
signal=signal1+j*signal2;
return;