Higher-Order Chaotic oscillator Using Active Bessel Filter

A higher-order oscillator, including a nonlinear unit and an 8th-order low-pass active Bessel ̄lter is described. The Bessel unit plays the role of \three-in-one": a delay line, an ampli ̄er and a ̄lter. Results of hardware experiments and numerical simulation are presented. Depending on the parameters of the nonlinear unit the oscillator operates either in a one-scroll or two-scroll mode. Two positive Lyapunov exponents, found at larger values of the negative slopes of the nonlinear function, characterize the oscillations as hyperchaotic.