how to generate chirp signal ?

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

Answer 1

[Sachin Ganjare]

Use matlab "chirp" function.