Studies on the Dynamics of Two Mutually Coupled Colpitts Oscillators

Abstract

In this paper, we have thoroughly examined the dynamics of a system of two mutually coupled Colpitts oscillators. Two bias-tuned Colpitts oscillators with identical structure are bilaterally coupled through direct coupling scheme.Numerically solving the system equations, it is observed that both the Colpitts oscillators oscillating in periodic mode become perfectly synchronized for some values of the coupling factors. For higher values of coupling factors, the system become chaotic.We have also studied the dynamics of two mutually coupled non-oscillatory Colpitts oscillators. With the increase of the coupling factors between two oscillators, birth of periodic oscillation observed. For increased value of coupling factors, system dynamics become chaotic.We develop conditions for periodic bifurcation in parameter space analytically and verified it through numerical solution of system equations. We also perform a simulation experiment using PSPICE circuit simulator in the radio frequency range with prototype Colpitts oscillator circuits and the experimental observations are in agreement with the numerical simulation results.