1. The problem statement, all variables and given/known data I have a bode plot with a positive phase. 2. Relevant equations this is a matlab code for the thing Code (Text): % bode phase plot w = logspace(1, 4, 100); G = 100*(1+0.017i*w)./(1i.*w.*(1+0.05i.*w).*(1+0.0025i.*w).*(1+0.001i.*w)); fi = atand(imag(G)./real(G)); semilogx(w, fi); % x-axis: log(omega*j), y-axis: phase in degrees 3. The attempt at a solution Nothing to solve, there's just one thing I don't get: if phase means "relation between input and output signal", how can output signal come before the input?