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Experimental Synchronization of Two Van der Pol Oscillators with Nonlinear and Delayed Unidirectional Coupling

Abstract This paper presents the experimental investigation on synchronization of two Van der Pol oscillators with polynomial and delay unidirectional couplings. The intervals of coupling coefficients and delay leading to synchronization are determined experimentally using analog electronic circuits. Three cases are considered: autonomous Van der Pol oscillators, sinusoidally exited Van der Pol oscillators in the chaotic state and Van der Pol oscillators with two slowly sinusoidal excitations delivering periodic patterns of periodic pulses. It is found that the degree of the polynomial coupling reduces the intervals of coupling coefficients leading to synchronization and the delay affects the coupling intervals in a periodic way. The experimental results agree well with the results of the theoretical (mathematical and numerical) investigation.