AEU - International Journal of Electronics and Communications, 2011
A new technique for passive doubly terminated ladder filters transformation has been proposed. Th... more A new technique for passive doubly terminated ladder filters transformation has been proposed. The proposed technique depends on current mode realization of doubly terminated LC ladder filters instead of voltage mode realizations presented by Constantinides and Dimopoulos in [1]. Different realizations of passive elements using new technique have been proposed. Design example of a 3rd order low-pass filter has been
AEU - International Journal of Electronics and Communications, 2015
ABSTRACT In this paper, a general analysis of the fractional order operational transresistance am... more ABSTRACT In this paper, a general analysis of the fractional order operational transresistance amplifiers (OTRA) based oscillator is presented and validated through eight different circuits which represent two classifications according to the number of OTRAs. The general analytical formulas of the oscillation frequency, condition as well as the phase difference are illustrated for each case and summarized in tables. One of the advantages of the fractional-order circuit is the extra degrees of freedom added from the fractional-order parameters. Moreover different special cases {α = β ≠ 1, β ≠ α = 1, α ≠ β = 1} are investigated where the conventional case α = β = 1 is included in all of them. Also, the effect of the fractional order parameter on the phase difference between the two oscillator outputs is presented which increases the design flexibility and controllability. The effect of the non-ideal characteristics associated with OTRA on the presented oscillator is also studied. A comparison between the fractional order oscillators with their integer order counterpart is also presented to verify the advantages of the added fractional order parameters. Numerical and spice simulations are given to validate the presented analysis.
2014 21st IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2014
ABSTRACT This paper presents a study of fractional order oscillators based on current feedback op... more ABSTRACT This paper presents a study of fractional order oscillators based on current feedback operational amplifiers (CFOA). Two general cases have been discussed for the oscillation frequency and condition with the use of two fractional order elements of different orders. Design procedure for the two general cases is illustrated with numerical discussions. Circuit simulations for some special cases are presented to validate the theoretical findings. The simulations have been done using Ad844 commercial CFOA model
Two-port network representations are applied to analyze complex networks which can be dissolved i... more Two-port network representations are applied to analyze complex networks which can be dissolved into sub-networks connected in series, parallel or cascade. In this paper, the concept of two-port network has been studied for oscillators. Three impedance oscillator based on two port concept has been analyzed using different impedance structures. The effect of each structure on the oscillation condition and the frequency of oscillation have been introduced. Two different implementations using MOS and BJT have been introduced.
AEU - International Journal of Electronics and Communications, 2011
A new technique for passive doubly terminated ladder filters transformation has been proposed. Th... more A new technique for passive doubly terminated ladder filters transformation has been proposed. The proposed technique depends on current mode realization of doubly terminated LC ladder filters instead of voltage mode realizations presented by Constantinides and Dimopoulos in [1]. Different realizations of passive elements using new technique have been proposed. Design example of a 3rd order low-pass filter has been
AEU - International Journal of Electronics and Communications, 2015
ABSTRACT In this paper, a general analysis of the fractional order operational transresistance am... more ABSTRACT In this paper, a general analysis of the fractional order operational transresistance amplifiers (OTRA) based oscillator is presented and validated through eight different circuits which represent two classifications according to the number of OTRAs. The general analytical formulas of the oscillation frequency, condition as well as the phase difference are illustrated for each case and summarized in tables. One of the advantages of the fractional-order circuit is the extra degrees of freedom added from the fractional-order parameters. Moreover different special cases {α = β ≠ 1, β ≠ α = 1, α ≠ β = 1} are investigated where the conventional case α = β = 1 is included in all of them. Also, the effect of the fractional order parameter on the phase difference between the two oscillator outputs is presented which increases the design flexibility and controllability. The effect of the non-ideal characteristics associated with OTRA on the presented oscillator is also studied. A comparison between the fractional order oscillators with their integer order counterpart is also presented to verify the advantages of the added fractional order parameters. Numerical and spice simulations are given to validate the presented analysis.
2014 21st IEEE International Conference on Electronics, Circuits and Systems (ICECS), 2014
ABSTRACT This paper presents a study of fractional order oscillators based on current feedback op... more ABSTRACT This paper presents a study of fractional order oscillators based on current feedback operational amplifiers (CFOA). Two general cases have been discussed for the oscillation frequency and condition with the use of two fractional order elements of different orders. Design procedure for the two general cases is illustrated with numerical discussions. Circuit simulations for some special cases are presented to validate the theoretical findings. The simulations have been done using Ad844 commercial CFOA model
Two-port network representations are applied to analyze complex networks which can be dissolved i... more Two-port network representations are applied to analyze complex networks which can be dissolved into sub-networks connected in series, parallel or cascade. In this paper, the concept of two-port network has been studied for oscillators. Three impedance oscillator based on two port concept has been analyzed using different impedance structures. The effect of each structure on the oscillation condition and the frequency of oscillation have been introduced. Two different implementations using MOS and BJT have been introduced.
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