How to add noise in input of State space model ?

I want to add noise signal in Input of state space model in code..G=ss(S,B,C,D).

I know to how to do in simulink, but don,t know ho to don in code

..please help me

Answer 1

[Star Strider]

Try this —

A = [-3 -1.5; 5 0];
B = [1; 0];
C = [0.5 1.5];
D = 0;
sys = ss(A,B,C,D);

t = linspace(0, 10, 1500);                                  % Time Vector
u = sum(sin((1:29)'*2*pi*t/2.5));                           % Arbitrary Input

figure
lsim(sys,u,t)
grid on

un = u + randn(size(u))*1.5;                                % Add Gaussian Noise (Standard Deviation = 1.5)

figure
lsim(sys,un,t)
grid on

Use any initial input ‘u’ vector appropriate to the model.

The model here is from the lsim documentation.

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