Electronically Tunable Fractional-order Multivibrator using OTA and Its Application as Versatile Modulator

Abstract In this paper, a multivibrator built around three Operational transconductance amplifiers (OTA) is generalized in fractional domain. Mathematical formulation for time period of the multivibrator is drafted using Reimann-Liouville fractional integral. The oscillation period and amplitude of the square wave are electronically tunable and can be controlled independently. The use of the fractional-order capacitor facilitates the multivibrator to have very high frequency oscillations using simple components, this feature of fractional-order multivibrator is explored as a versatile modulator (i.e., amplitude modulator, frequency modulator, delta modulator and sigma-delta modulator), the adjustment of modulation index of analog modulators has also been examined.