MATLAB: How to generate chirp signal

chirpodeoscillator

How to generate chirp signal for this scenario?
Hello , i have adaptive oscillator matlab code .
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function dz = myeqd(t,y,ti,fi)
dz = zeros(3,1);
mu=0.7;
r= sqrt(y(1)^2 + y(2)^2);
K=2;
%w=40;
F=interp1(ti,fi,t);
dz(1)= (mu – r^2)*y(1) – y(3)*y(2) +K*F;
dz(2) = (mu – r^2)*y(2) + y(3)*y(1);
dz(3) = (-K*F) * (y(2)/sqrt(y(1)^2 + y(2)^2));
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then call this function
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Tspan= 0:0.01:500; % time vector
fi = cos(10*Tspan)+ 0.1*randn(1,numel(Tspan));
ti=Tspan;
[T,Y]=ode45(@(t,y) myeqd(t,y,ti,fi),Tspan,[1;1;30]);
plot (T,Y(:,3))
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In the above code i am giving fi = cos(10*Tspan)+ 0.1*randn(1,numel(Tspan)) external input signal but instead of this I want to test this code for Chirp signal as an external input and i am not getting how to give chirp signal .
any one can help me
thank you

Best Answer

Use matlab "chirp" function.