TELK OMNIKA T elecommunication, Computing, Electr onics and Contr ol V ol. 23, No. 6, December 2025, pp. 1635 1645 ISSN: 1693-6930, DOI: 10.12928/TELK OMNIKA.v23i6.27250 1635 No v el fractional order sinusoidal oscillators using operational trans r esistance amplier Battula T irumala Krishna 1 , V anitha Kak ollu 2 , Manchala Madhusudhan Prasad 3 1 Department of Electronics and Communication Engineering, Uni v ersity Colle ge of Engineering Kakinada, Ja w aharlal Nehru T echnological Uni v ersity Kakinada, Kakinada, India 2 Department of Computer Science, GIT AM School of Science, GIT AM Uni v ersity , V isakhapatnam, India 3 Department of Mechanical Engineering, Uni v ersity Colle ge of Engineering Kakinada, Ja w aharlal Nehru T echnological Uni v ersity Kakinada, Kakinada, India Article Inf o Article history: Recei v ed May 26, 2025 Re vised Sep 12, 2025 Accepted Oct 19, 2025 K eyw ords: Acti v e element Continued fraction e xpansion Fractional order Frequenc y of oscillation virtual ground Sinusoidal oscillator Sinusoidal signal ABSTRA CT The design of fractional order circuits in v ery lar ge-scale inte gration (VLSI) domain is g aining the interest of man y researchers. At the same time design of fractional circuits using the current mode de vices is attracting the research community . In this paper , se v eral possible fractional order sinusoidal oscillators using operational trans resistance amplie r (O TRA) as a basic b uilding block is presented. The necessary condition for the frequenc y of oscillation and condi- tion for oscillations is deri v ed. Fractional order operator s α is the mos t crucial one to be approximated. In this paper , the frac tional order element is approxi- mated by the continued fraction e xpansion (CFE). The approximation is carried out up to fth order . The circuits are tested with the simulation softw are named L Tspice. The results agree with the theoretical one. The proposed circuits of- fers a frequenc y of 15 MHz, 20 MHz, and 25 MHz which is higher in v alue as compared to the e xisting circuits. The proposed circuits nds applications in bio medical, communication circuits. This is an open access article under the CC BY -SA license . Corresponding A uthor: Battula T irumala Krishna Department of Electronics and Communication Engineering, Uni v ersity Colle ge of Engineering Kakinada Ja w aharlal Nehru T echnological Uni v ersity Kakinada Kakinada, India 533003 Email: tkbattula@gmail.com 1. INTR ODUCTION The circuit which is capable of producing oscillations without an y e xternal input is called an oscilla tor [1]. This can be sinusoidal or relaxation type oscillator . The sinusoidal oscillators nd wide applications in the areas of control systems, signal processing, communications and other elds. Con v entionally operational amplier is used to be the acti v e element. Man y of the lter circuits, oscillators (sinusoidal as well as relaxation) are proposed in the literature with operational amplier as a basic element. Fractional-order oscillators possess se v eral uses in engineering and ph ysics, pro viding more preci se models of real-w orld systems by ef fecti v ely capturing memory and h ysteresis phenomena. Principal applica- tions encompass vibrati on control and structural healt h monitoring, sophisticated ltering and signal processing within communication systems, the generation of intricate signals for chaotic systems and security applications such as v oice encryption, as well as the modeling of complicated phenomena in bio engineering. J ournal homepage: http://journal.uad.ac.id/inde x.php/TELK OMNIKA Evaluation Warning : The document was created with Spire.PDF for Python.
1636 ISSN: 1693-6930 There are se v eral number of acti v e elements present in the literature such as current con v e yor , op- erational transconductance amplier , current feedback operati onal amplier , and operational trans resistance amplier . Fe w of them are a v ailable commercially also. These de vices ha v e their o wn adv antages and disad- v antages [2]. In this article, operational trans resistance amplier (O TRA) is considered as an acti v e de vice as in [3], [4]. Realization of fractional oscillator is not an old topic dates back to 2000 [5]. Similarly non sinusoidal oscillators are also designed in [6]. No v el topologie s of sinusoidal oscillators are proposed in [7] and are simulated using Orcad PSpice . Fractional-order oscillators emplo y fracti onal-order capacitors or inductors, enhancing the design e xibility and tunability of oscillat o r s relati v e t o con v entional inte ger -order oscillators [8]. These oscillators are characterized by non-inte ger -order dif ferential equations, pro viding control o v er oscillation frequenc y and phase. T w o oscillator topologies with tw o impedances for a uni v ersal fractional order osci llator based on a tw o port netw ork are co v ered in paper [7], [8]. The tw o fractional impedances can be combined in four w ays for each topology . A thorough analysis and design of fractional-or d e r oscillators using double Op-Amps are presented in the paper in [9]. T o v erify ho w the fractional order af fects the oscillation parameters, MA TLAB simulations are analyzed. The numerical solution in [9] is v alidated by PSpice simul ations and e xperimental results. Ahmad et al. [10], a fractional order W ien bridge oscillator based on state space equations is proposed. Carlson approximation, mastudas approximation, po wer series e xpansion, and continued fraction e x- pansion can all be used to realize fractional order transfer functions. Continued fraction e xpansion has yielded better r esults as compared to other s [11]. A fractional order sinusoidal os cillator (FSO) with tw o f ractional ca- pacitors, four resistors, and one O TRA is pro vided by the w ork in [12]. Nodal analysis w as used to determine the frequenc y , condition, and phase dif ference between the output v oltages of the proposed fractional order oscillator and simulations are carried out using PSpice. A dif ferential v oltage current con v e yo r (D VCC) based fractional order Butterw orth lo wpass lter is realized in [13]. A tw ofold comple xity , fractional-order dual coupling duf ng system is proposed in the study [14] to detect ship-radiated noise. Jacobi collocation and nested picard iteration (NPI) are used in [15] to solv e the fractional order oscillatory che mical reaction model. The outcomes of the NPI and Jacobi collocation approaches are strikingly similar . K ubanek et al. [16], the transfer functions of order (1 + α ) are proposed. Tsirimok ou et al. [17] discusses the use of fractional order analog circuits in medicine. In study [18], [19], fractional lters with v oltage dif ferencing transconductance amplier (VDT A) are suggested and modeled. Sac ¸ u and Alc ¸ ı [20] designs and simulates a lo w-v oltage, lo w-po wer , operational transconductance amplier (O T A)-based fractional order lo w-pass and high-pass lter of order ( n + α ) using Cadence-PSpice, where 0 < α < 1 and n < 1 . Sac ¸ u and Alc ¸ ı [21] describe a uni v ersal lter topology with lo w-v oltage acti v e elements that of fer all types of responses in a single circuit. Tsirimok ou et al. [22] proposed no v el fractional-order generalized lter topologies. multiple-feedback topologies and operational transconductance ampliers were used to achie v e the abo v e. The proposed designs are v alidated by simulations using Cadence inte grated circuit (IC) design suite and the Austrian micro systems design kit. Ne w fractional order inte grator implementation methods are pro vided in [23]. After analyzi ng inte ger order approximation methods, fractional order inte grators with acti v e circuit elements are des igned utilizing successfully implemented approximate methods from the literature. Historical perspecti v e of the fractional order elements is presented by Kartci et al. [24], the mathe- matical e xpressions for the fractional order circuits using tw o ladder elements is de v eloped in [25]. Current mode fractional order dif ferentiators and inte grators is proposed in [26] which are recongurable. The objec- ti v e of the study in [27] is to use commercially a v ailable L T1228 ICs with three inputs and one output (TISO) to de v elop an electronically tunable v oltage-mode (VM) uni v ersal lter . T w o L T1228s, four resistors, and tw o grounded capacitors mak e up the recommended lter . PSpice simulation and hardw are implementation sup- port the suggested lter’ s performance. Arora [28] in v estig ates the potential uses of v oltage dif ferencing current con v e yors (VDCC) as sinusoidal oscillators and current mode uni v ersal lters. Only grounded passi v e compo- nents and a smal l number of acti v e elements were used in the resultant netw ork. The digitally programmable complementary metal–oxide–semiconductor (CMOS) is used to de v elop a digital modulation system in [29]. PSpice softw are is used to sim ulate and analyze this ne w communication approach. The study suggests further research on noise resistance in digitally programmable (DP) modulation techniques and e xploring digitally programmable CMOS technology-enabled modulation methods lik e quadrature amplitude modulation (QAM) or orthogonal frequenc y di vision multiple xing (OFDM). TELK OMNIKA T elecommun Comput El Control, V ol. 23, No. 6, December 2025: 1635–1645 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA T elecommun Comput El Control 1637 A current-controlled current con v e yor second generation (CCCII)-bas ed shado w lter and oscill ator is presented in the study in [30]. Natural frequenc y and lter quality f actor are determined by CCCII current g ains. It is simpler to combine the resistorless lter with grounded capacitors. In a single topology , the lter utilizes input signals to generate all types of transfer functions. T o conrm the unique architecture, simulation program with inte grated circuit emphasis (SPICE) simulates the suggested circ u i t using A T&T ALA400-CBIC- R bipolar transistor arrays. In this paper , the con v entional capacitor s are replaced with fractional order one. The necessary e x- pression for frequenc y of oscillation, condition for sustained oscillations are deri v ed. By v arying the v alues of fractional order , the output v ariat ion is studied. The simulations are carried out using L Tspice. The results agree with the theoretical one. The paper is structured as follo ws. Section 2 deals with the rational approximations. Section 3 d e als with the deri v ation for frequenc y of oscillation and condition for sustained oscillations. Implem entation of the circuits and results are presented in section 4. Section 5 deals with the conclusions. 2. PR OPOSED MA THEMA TICAL METHODS 2.1. Rational appr oximations T o calculate the inte ger -order rational fractance approximations, a number of frequenc y-domain ap- proximation techniques ha v e been documented in the literature [11]. This te chnique is popular for function e v aluation because it e xpands the comple x plane’ s domain more quickly than po wer series e xpansions. Con- tinued fraction e xpansion is described by considering the continued fraction e xpansion of (1 + x ) α as: (1 + x ) α = 1 1 αx 1+ (1+ α ) x 2+ (1 α ) x 3+ (2+ α ) x 2+ (2 α ) x 5+ ..... ( N + α ) x 2+ ( N α ) x 2 N +1 (1) Substituting x = s 1 , and considering the rst ten terms the rational function is gi v en by [11]. s α = P 0 s 5 + P 1 s 4 + P 2 s 3 + P 3 s 2 + P 4 s + P 5 Q 0 s 5 + Q 1 s 4 + Q 2 s 3 + Q 3 s 2 + Q 4 s + Q 5 (2) The co-ef cients P 0 , P 1 , ....P 5 , Q 0 , Q 1 , ......Q 5 are gi v en by: P 0 = Q 5 = α 5 15 α 4 85 α 3 225 α 2 274 α 120 P 1 = Q 4 = 5 α 5 + 45 α 4 + 5 α 3 1005 α 2 3250 α 3000 P 2 = Q 3 = 10 α 5 30 α 4 + 410 α 3 + 1230 α 2 4000 α 12000 P 3 = Q 2 = 10 α 5 30 α 4 410 α 3 + 1230 α 2 + 4000 α 12000 P 4 = Q 1 = 5 α 5 + 45 α 4 5 α 3 1005 α 2 + 3250 α 3000 P 5 = Q 0 = α 5 15 α 4 + 85 α 3 225 α 2 + 274 α 120 (3) The magnitude, phase and err or responses of the ideal and approximated functions for α = 0 . 5 and α = 0 . 25 are as sho wn in Figure 1. From the Fi gure 1 it is e vident that the proposed response matches the ideal one for lar ger range of frequencies in both magnitude and Phase. The error is minimum in the range of frequencies from [10 2 ] to [10 2 ] Hz. The v alues of the 5 th order coef cients obtained for v arious α is tab ulated in T able 1. The synthesized resistor–capacitor (RC) netw ork v alues using partial fraction e xpansion method are as sho wn in T able 2. One of the possible synthesized RC netw ork is as sho wn in Figure 2. In the ne xt section details of the current mode de vice named operational transresistance amplier is e xplained. No vel fr actional or der sinusoidal oscillator s using oper ational tr ans ... (Battula T irumala Krishna) Evaluation Warning : The document was created with Spire.PDF for Python.
1638 ISSN: 1693-6930 Figure 1. Magnitude, phase, and error plots T able 1. 5 th order approximated coef cents for v arious v alues of α α P 0 P 1 P 2 P 3 P 4 P 5 0.1 149.7365 3.3350e+03 1.2387e+04 1.1588e+04 2.6851e+03 94.7665 0.2 184.5043 3.6901e+03 1.2748e+04 1.1154e+04 2.3902e+03 73.5437 0.3 224.8689 4.0649e+03 1.3078e+04 1.0701e+04 2.1152e+03 55.8741 0.4 271.4342 4.4593e+03 1.3378e+04 1.0230e+04 1.8600e+03 41.3338 0.5 324.8438 4.8727e+03 1.3643e+04 9.7453e+03 1.6242e+03 29.5313 0.6 385.7818 5.3045e+03 1.3873e+04 9.2489e+03 1.4074e+03 20.1062 0.7 454.9746 5.7541e+03 1.4066e+04 8.7435e+03 1.2092e+03 12.7284 0.8 533.1917 6.2206e+03 1.4218e+04 8.2317e+03 1.0290e+03 7.0963 0.9 621.2470 6.7029e+03 1.4330e+04 7.7164e+03 866.1229 2.9360 T able 2. Resistor and capacitor v alues for 5 th approximation α R a R b C b R c C c R d C d R e C e R f C f 0.1 0.6329 0.1849 0.3024 0.1163 2.7561 0.1126 9.3996 0.1535 23.2565 0.3798 61.4173 0.2 0.3986 0.2569 0.2450 0.1970 1.7371 0.2183 5.1342 0.3432 11.1552 1.0947 24.7963 0.3 0.2485 0.2652 0.2652 0.2448 1.4900 0.3100 3.8278 0.5648 7.2878 2.3913 13.4318 0.4 0.1523 0.2394 0.3262 0.2634 1.4742 0.3809 3.3000 0.8080 5.4904 4.7229 8.2238 0.5 0.0909 0.1975 0.4366 0.2569 1.6076 0.4240 3.1414 1.0536 4.5509 8.9771 5.3886 0.6 0.0521 0.1503 0.6302 0.2296 1.9113 0.4325 3.2646 1.2681 4.0999 17.0544 3.6856 0.7 0.0280 0.1043 0.9941 0.1859 2.5063 0.4000 3.7450 1.3956 4.0548 33.6310 2.5950 0.8 0.0133 0.0629 1.7977 0.1302 3.7972 0.3203 4.9649 1.3438 4.6034 73.2658 1.8647 0.9 0.0047 0.0279 4.4048 0.0668 7.8470 0.1883 8.9763 0.9616 7.0677 210.3463 1.3590 R a R b C b R c C c R d C d R e C e R f C f Figure 2. Fifth order approximated fractance TELK OMNIKA T elecommun Comput El Control, V ol. 23, No. 6, December 2025: 1635–1645 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA T elecommun Comput El Control 1639 2.2. Operational trans r esistance amplier Analog IC designers ha v e recently paid a lot of attention to O TRA. O TRA is an acti v e g adget wi th three terminals. The output v oltage of O TRA is dependent on the input current and can be sho wn as the transfer matrix. V p V n V 0 = 0 0 0 0 0 0 R m R m 0 I p I n I 0 (4) where R m is the trans-resistance g ain of the O TRA. The output v oltage V 0 is gi v en by (5). V 0 = R m ( I p I n ) (5) The blockdiagram of O TRA is as sho wn in Figure 3. Figure 3. Blockdiagram of O TRA In v erting and nonin v erting O TRA are possible. Both scenarios ha v e the same g ain. O TRA w as pro- posed in 1992 and is used in analog signal processing. The follo wing subsections e xplain the e xisting O TRA circuits named Salama O TRA and CMOS based O TRA as sho wn in Figures 4(a) and (b). (a) (b) Figure 4. Dif ferent types of operational transconductance amplier: (a) salama O TRA and (b) O TRA using CMOS 2.2.1. Salama O TRA The modied dif ferential current con v e yor (MDCC) and common source amplier are cascaded to form the CMOS realization of O TRA, as illustrated in Figure 4(a). While the common source amplier pro vides high g ain, MDCC performs current dif ferencing and ef fecti v ely grounds the tw o input terminals. The current mirror is created by ( M 1 M 4 ). The output v oltage in the O TRA design is produced by biasi ng the output stage transistors with currents M 9 and M 11 . 2.2.2. CMOS based O TRA A viable CMOS O TRA internal circuit construction is sho wn in Figure 4(b) and consists of tw o pri- mary functional blocks: a v oltage b uf fer circuit and a dif ferential-current-controlled current source. All P- channel metal–oxide–semiconductor (PMOS) and N-channel metal–oxide–semiconductor (NMOS) transistors No vel fr actional or der sinusoidal oscillator s using oper ational tr ans ... (Battula T irumala Krishna) Evaluation Warning : The document was created with Spire.PDF for Python.
1640 ISSN: 1693-6930 in this circuit ha v e their substrate terminals connected to positi v e and ne g ati v e supply v oltages, respecti v ely . As current reectors, transistors M 1 , M 3 , and M 5 guarantee that the currents o wing through transistors M 9 and M 10 are equal. Similarly , equal currents are forced into tra n s istors M 7 and M 8 by the current mirrors composed of M 2 , M 4 , and M 6 . T ransistors M 1 and M 2 ha v e grounded sources. 3. METHODOLOGY FOLLO WED This section pro vides the proposed fractional order oscillators. Three of the circuits e xisting in [7] are modied by replacing the capacitors by fractional order one and the conditi o ns for sustained oscillations and frequenc y of oscillations is deri v ed. 3.1. O TRA based fractional order sinusoidal oscillators The generalized block diagram of O TRA based fractional order sinusoidal oscillators is as sho wn in Figure 5. Let V a be the v oltage at the interconnection of Y 1 , Y 3 , Y 4 , Y 6 and Y 7 . The currents at the in v erting and non-in v erting terminals can be written as: V 0 Y 2 + V a Y 3 = I p (6) V 0 Y 5 + V a Y 4 = I n (7) From the ideal beha vior od O TRA since the current I p , I n to be equal, V 0 = V a Y 4 Y 3 Y 2 Y 5 (8) Writing KCL at node a , V 0 ( Y 1 + Y 6 ) = V a ( Y 1 + Y 3 + Y 4 + Y 6 + Y 7 ) (9) Substituting the v alues of V a and simplifying the characteristic equation for the oscillator is going to be: Y 1 Y 2 +Y 2 Y 3 +Y 2 Y 4 +Y 2 Y 6 +Y 2 Y 7 +Y 1 Y 3 +Y 3 Y 6 Y 1 Y 5 Y 1 Y 4 Y 4 Y 6 Y 3 Y 5 Y 4 Y 5 Y 5 Y 6 Y 5 Y 7 = 0 (10) Dif ferent topologies can be obtained by changing the v alues of Y s. Some of the possible topologies by replac- ing Y with fractional order capacitor are as e xplained in the coming sections. Figure 5. Blockdiagram of O TRA based sinusoidal oscillator 3.2. Case A Y 1 = Y 6 = 0 , Y 2 = s α C 2 , Y 4 = s β C 4 , the characteristic equation becomes, Y 2 Y 3 + Y 2 Y 4 + Y 2 Y 7 Y 3 Y 5 Y 4 Y 5 Y 5 Y 7 = 0 . On substituting the v alues of Y s and simplifying the equations for the frequenc y of operation and condition for oscillations will be: ω α + β cos ( α + β ) π 2 c 2 c 4 + ω α cos απ 2 c 2 ( G 3 + G 7 ) ω β cos β π 2 G 5 c 4 G 5 ( G 3 + G 7 ) = 0 (11) ω α + β sin ( α + β ) π 2 c 2 c 4 + ω α sin α π 2 c 2 ( G 3 + G 7 ) ω β sin β π 2 G 5 c 4 = 0 (12) TELK OMNIKA T elecommun Comput El Control, V ol. 23, No. 6, December 2025: 1635–1645 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA T elecommun Comput El Control 1641 3.3. Case B Y 2 = Y 4 = 0 , Y 5 = s α C 5 , Y 6 = s β C 6 , the characteristic equation becomes, Y 1 Y 3 + Y 3 Y 6 Y 1 Y 5 Y 3 Y 5 Y 6 Y 5 Y 5 Y 7 = 0 . On substituting the v alues of Y s and simplifying the equations for the frequenc y of operation and condition for oscillations will be: ω α + β cos ( α + β ) π 2 c 5 c 6 + ω α cos απ 2 c 5 ( G 1 + G 3 + G 7 ) ω β cos β π 2 G 3 c 6 G 1 G 3 = 0 (13) ω α + β sin ( α + β ) π 2 c 5 c 6 + ω α sin α π 2 c 5 ( G 1 + G 3 + G 7 ) ω β sin β π 2 G 3 c 6 = 0 (14) 3.4. Case C Y 1 = Y 5 = 0 , Y 3 = s α C 3 , Y 6 = s β C 6 , the characteristic equation becomes, Y 1 Y 3 + Y 3 Y 6 Y 1 Y 5 Y 3 Y 5 Y 6 Y 5 Y 5 Y 7 = 0 . On substituting the v alues of Y s and simplifying the equations for the frequenc y of operation and condition for oscillations will be: ω α + β cos ( α + β ) π 2 c 3 c 6 + ω α cos απ 2 G 2 c 3 + ω β cos β π 2 ( G 2 c 6 G 4 c 6 ) + G 2 ( G 4 + G 7 ) = 0 (15) ω α + β sin ( α + β ) π 2 c 3 c 6 + ω α sin α π 2 G 2 c 3 + ω β sin β π 2 ( G 2 c 6 G 4 c 6 ) = 0 (16) 3.5. Special cases The follo wing analysis illustrates the inuence of the fractional order on the oscillation parameters. α = β = 1 s α + β = e j π ω 2 = ω 2 s α = e j π 2 ω = j ω (17) The frequenc y of oscillation is found to be: ω 2 k 1 + k 4 = 0 ω 2 = k 4 /k 1 (18) The condition for the sustained oscillations becomes: k 2 + k 3 = 0 (19) α = β ̸ = 1 cos ( α π ) cos απ 2 = 1 , sin ( α π ) α π , sin απ 2 απ 2 . Substituting the abo v e conditions and simplifying (20). ω 2 α k 1 + 1 2 ( ω α k 2 + ω α k 3 ) = 0 (20) The (20) reduces to: ω α = k 2 + k 3 2 k 1 (21) Substituting the abo v e condition in the (22). ω 2 α k 1 + ω α k 2 + ω α k 3 + k 4 = 0 (22) This (22) reduces to: k 2 + k 3 = 2 p k 1 k 4 (23) No vel fr actional or der sinusoidal oscillator s using oper ational tr ans ... (Battula T irumala Krishna) Evaluation Warning : The document was created with Spire.PDF for Python.
1642 ISSN: 1693-6930 The deri v ed e xpressions for frequenc y of oscillations and condition for sustained oscillations for both the cases, α = β = 1 and α = β ̸ = 1 are tab ulated in T able 3. T able 3. Conditions of oscillators α = β = 1 α = β ̸ = 1 Circuit ω Condition ω α Condition Case A q G 5 ( G 3 + G 7 ) c 2 c 4 c 2 ( G 3 + G 7 ) = G 5 c 4 G 5 c 4 c 2 ( G 3 + G 7 ) 2 c 2 c 4 c 2 ( G 3 + G 7 ) = G 5 c 4 Case B q G 1 G 3 c 5 c 6 c 5 ( G 1 + G 3 + G 7 ) = G 3 c 6 G 5 c 6 c 5 ( G 1 + G 3 + G 7 ) 2 c 5 c 6 c 5 ( G 1 + G 3 + G 7 ) = G 3 c 6 Case C q G 2 ( G 4 + G 7 ) c 3 c 6 c 6 G 4 = G 2 ( c 3 + c 6 ) G 4 c 6 G 2 c 6 G 2 c 3 2 c 3 c 6 G 2 c 3 + G 2 c 6 G 4 c 6 = 2 p G 2 c 3 c 6 ( G 4 + G 7 ) 4. RESUL TS AND DISCUSSIONS The proposed circuits in three cases has been simulated using L Tspice. The fractional order of v alue 0.5 is chosen and the simulations are carried out for all the three topologies. The component v alues used for the simulation are Case A ( Y 3 = 60Ω , Y 5 = 1000Ω , Y 7 = 300Ω ), Case B ( Y 3 = 150Ω , Y 7 = 15Ω ), Case C ( Y 2 = 1000Ω , Y 4 = 60Ω , Y 7 = 50Ω ). The obtained results are as sho wn in Figure 6. The f ast fourier transform (FFT) analysis is depicted in Figure 7 and the corresponding results are tab ulated in T able 4. Figure 6. Simulation results for Case A circuit Figure 7. FFT analysis of Case A circuit TELK OMNIKA T elecommun Comput El Control, V ol. 23, No. 6, December 2025: 1635–1645 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA T elecommun Comput El Control 1643 T able 4. FFT Analysis of proposed oscillators S. no T ype of circuit Frequenc y Magnitude(dB) 1 Circui t A 15MHz -138 2 Circuit B 20 MHz -148 3 Circuit C 25 MHz -150 5. CONCLUSION The main purpose of this paper is to propose a no v el fractional order oscillator using opera tional transconductance amplier . The deri v ati on s pertaining to the fractional order sense are deri v ed. The basic idea of the oscillator is de v eloped by replacing con v entional capacitors with fractional-order elements. The frac- tional order elements are to be approximated by a rational approximations to a nite order . In this paper , the rational approximation of the fractional elements is obtained using a continued-fraction e xpansion approach. The mathematical equations for the sustained oscillations is deri v ed in terms of fractional order and are tab- ulated. The special cases of similar fractional order and dissimilar fractional orders is also discussed. F or simulation purpose the fractional order α = 0 . 5 is chosen. The v alues chosen for the simulation are also indi- cated. The FFT analysis of the results is carried out. It has been observ ed that at α = β = 1 , the e xpressions are similar to the e xpressions for the con v entional oscillators. The theoretical v alues of oscillation frequenc y is pro v en to be same as the theoretical one. The circuits proposed are simple and can be used in communications, encryption and decryption applications. A CKNO WLEDGEMENTS The authors are deeply indebted to administration of Ja w aharlal Nehru T echnological Uni v ersity Kak- inada, Gitam Uni v ersity for the support. The authors also wish the anon ymous re vie wers for the suggestions to impro v e the manuscript. FUNDING INFORMA TION Authors state no funding in v olv ed. A UTHOR CONTRIB UTIONS ST A TEMENT The corresponding author will be responsible for all conceptualization, methodology , formal analys is, or in v estig ation, as well as at least one aspect of writing. Name of A uthor C M So V a F o I R D O E V i Su P Fu Battula T irumala Krishna V anitha Kak ollu Manchala Madhusudhan Prasad C : C onceptualization I : I n v estig ation V i : V i sualization M : M ethodology R : R esources Su : Su pervision So : So ftw are D : D ata Curation P : P roject Administration V a : V a lidation O : Writing - O riginal Draft Fu : Fu nding Acquisition F o : F o rmal Analysis E : Writing - Re vie w & E diting CONFLICT OF INTEREST ST A TEMENT Authors state no conict of interest. D A T A A V AILABILITY The data can be a v ailable from the author with request. No vel fr actional or der sinusoidal oscillator s using oper ational tr ans ... (Battula T irumala Krishna) Evaluation Warning : The document was created with Spire.PDF for Python.
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