Design and realisation of a fractional‐order sinusoidal oscillator

Abstract

In this work, a new fractional-order sinusoidal oscillator is proposed. The proposed oscillator consists of one fractional-order all-pass filter and one fractional-order lossless integrator blocks. In order to emulate fractional-order capacitors, three different approximation methods the R-C pair, Matsuda and Oustaloup are employed and the results are compared. Three sinusoidal voltage signals with different phases that are controlled by fractional orders are provided by the proposed oscillator topology that is not possible for the classical integer-order case. Grounded passive components are used in the introduced oscillator circuit. Additionally, the output voltage signals are available at the low impedance terminal W of AD844ANs. Moreover, the time constant of the fractional-order all-pass filter can be adjusted accurately by means of second resistor R x in the all-pass filter section. In addition to the simulation results, the proposed fractional oscillator is also implemented to verify the oscillator circuit experimentally. For the case of fractional orders α = 1 and β = 0.5, the measurement results are 10.3 kHz, 43.22° and 67.99°, respectively, while the desired values are 10 kHz, 45° and 67.36°, respectively.

Single‐differential difference current conveyor‐based first‐order VM/TAM universal filter and its applications

“…Name 11,15,42,44,50 The differential difference current conveyor (DDCC) has been widely used in the design of various analog signal processing and analog signal generation circuits such as in the design of second-order filters, second and third-order sinusoidal oscillators, and square wave generators. [51][52][53][54][55][56][57][58][59] However, very few circuits of first-order universal filters have been designed using the DDCC. 35,60,61 A brief account of first-order filters based on DDCC is given in the following to put the proposed work in proper perspective.…”

“…The differential difference current conveyor (DDCC) has been widely used in the design of various analog signal processing and analog signal generation circuits such as in the design of second‐order filters, second and third‐order sinusoidal oscillators, and square wave generators 51–59 . However, very few circuits of first‐order universal filters have been designed using the DDCC 35,60,61 .…”