%% Erstellung der Messdaten
[t,x] = ode45('model',t,x0');

% Build measurement vectors
t_meas      = t(1:1:end); 
x_meas(:,1) = x(1:1:end,2);
x_meas(:,2) = x(1:1:end,3);

% Add measurement Noise (White Noise)
v      = randn(length(t_meas),2);
v(:,1) = v(:,1)*sqrt(R(1,1));
v(:,2) = v(:,2)*sqrt(R(2,2));

y_meas(:,1) = x_meas(:,1) + v(:,1);
y_meas(:,2) = x_meas(:,2) + v(:,2);

% Calculate the 4th state (kAB)
K = 1;
kAB0 = 0.5;
x(:,4) = kAB0.*(1-exp(-K.*x(:,1)));