Measuring the best linear approximation of Wiener systems using multilevel sequences

The problem of measuring the best linear approximation of a nonlinear system by means of multilevel excitation sequences is analyzed. A comparison between different types of sequences applied at the input of Wiener systems is provided by numerical simulations. The performance of the sequences is compared with a white Gaussian noise signal for reference purposes. It is shown that the randomized constrained approach for designing ternary sequences has a low sensitivity to even and odd order nonlinearity, resulting in a response close to the actual response of the underlying linear system.