Şengül, Metin

Şengül, Metin

Name Variants

Şengül, Metin
M.,Şengül
M. Şengül
Metin, Şengül
Sengul, Metin
M.,Sengul
M. Sengul
Metin, Sengul
Şengül, Metin Y.
Şengül,M.

Job Title

Prof. Dr.

Email Address

Msengul@khas.edu.tr

Full item page

Scholarly Output

76

Articles

49

Citation Count

0

Supervised Theses

5 Scholarly Output Search Results

Now showing 1 - 10 of 76

Reflectance-Based Foster Impedance Data Modeling
(Fachverlag Schiele Schon, 2007) Şengül, Metin Y.; Şengül, Metin
A reflectance-based method is presented to model a set of given Foster impedance data as a lossless singly terminated two-port consisting of lumped-elements in short or open termination. The basis of the new method rests on the interpolation of the given data as a realizable bounded-real (BR) reflection function. The desired circuit model is obtained by synthesizing this function. An algorithm to generate the circuit model is presented and an example is included which illustrates the utilization of the proposed modeling method.
A Broadband Microwave Amplifier Design by Means of Immittance Based Data Modelling Tool
(IEEE, 2002) Kilinç, Ali; Şengül, Metin; Pinarbaşi, Haci; Şengül, Metin Y.; Yarman, Sıddık Binboğa
In this paper a practical broadband microwave amplifier design algorithm is introduced utilizing the immittance data-modelling tool. In the course of design first the optimum input and output terminations for the active device are produced employing the real frequency technique. Then these terminations are modelled utilizing the new immittance-modelling tool to synthesize the front-end and back-end matching networks. An example is included to exhibit the implementation of the proposed design algorithm to construct a single stage BJT amplifier over a wide frequency band. It is expected that the proposed design algorithm will find applications to realize wideband microwave amplifiers put on MMIC for mobile communication.
Design of Mixed-Element Networks Via Modeling
(IEEE, 2008) Şengül, Metin Y.; Şengül, Metin; Yarman, Sıddık Binboğa
A new method is introduced to design mixed lumped and distributed element network
Design of Broadband Single Matching Networks
(Elsevier GMBH Urban & Fischer Verlag, 2009) Şengül, Metin Y.; Şengül, Metin
In general commercially available software tools are preferred to design broadband matching networks for wireless communication systems. But they need a properly selected matching network topology with good initial element values. Therefore in this paper a new real frequency technique is presented to generate broadband single matching networks with suitable initial element values. In the proposed method load impedance is written in terms of ABCD-parameters of the desired matching network and the source resistor. Then free parameters are optimized which in turn yields the desired matching network with initial element values. It is not needed to select a circuit topology for the matching network which is the natural consequence of the matching processes. Also there is no need to select the desired transducer power gain level , the proposed technique naturally provides a gain curve fluctuating around the final available level. Eventually the initial design is improved by optimizing the performance of the matched system employing the commercially available computer-aided design (CAD) packages. An algorithm and two examples are given to illustrate the utilization of the proposed technique. (C) 2007 Elsevier GmbH. All rights reserved.
Explicit Synthesis Formulae for Cascaded Lossless Commensurate Lines
(Fachverlag Schiele Schon, 2008) Şengül, Metin Y.; Şengül, Metin
In literature synthesis of cascaded lossless commensurate lines have been realized via some iterative methods. So to be able to obtain the value of an element which is not the first one the designer has to obtain all the values of the elements connected before the desired one. But in this paper explicit synthesis formulae of the networks containing cascaded lossless commensurate lines up to three have been derived analytically and all the element values can be calculated independently.
Design of Distributed-Element Rf Filters Via Reflectance Data Modeling
(Elsevier GMBH Urban & Fischer Verlag, 2008) Şengül, Metin Y.; Şengül, Metin; Yarman, Sıddık Binboğa; Volmer, Christian; Hein, Matthias A.
A reflectance-based modeling method is presented to obtain the distributed-element counterpart of a lumped-element network which is described by measured or computed reflectance data at a set of frequencies. Numerical generation of the scattering parameters forms the basis of this modeling tool. It is not necessary to select a circuit topology for the distributed-element model which is the natural consequence of the modeling process. Our approach supplements the known interpolation methods by a simple technique that does not involve complicated cascaded circuit topologies and whose numerical convergence is proven. To illustrate the utilization of the proposed method a lumped-element low-pass Chebyshev filter is transformed to its distributed-element counterpart. The filter designed for a frequency band around 1 GHz was fabricated and experimentally characterized. We find excellent agreement between measured and simulated transducer power gain over the entire frequency band. (c) 2007 Elsevier GmbH. All rights reserved.
Circuit Model for Given Reflectance Data Constructed With Mixed Lumped and Distributed Elements for High Speed/High Frequency Communication Systems
(IEEE Computer Society, 2005) Yarman, Binboğa Sıddık; Şengül, Metin; Şengül, Metin Y.; Kılınç, Ali; Aksen, Ahmet
In this paper, a reflectance-based "non linear interpolation method" is presented to model the measured or computed data, obtained from a "passive one-port physical device" using mixed lumped and distributed elements. Mixed element model is constructed with cascade connection of series inductors [L], commensurate transmission lines or so called Unit Elements [UE] and shunt capacitors[C]. Basis of the new model rests on the numerical generation of the scattering parameters of the lossless two-port constructed with cascade connection of simple [L]-[UE]-[C] elements which describes a lossless 2-port in Darlington sense. The new modeling technique does not require direct optimization of the circuit elements of the selected topology. Rather, two-variable reflection coefficient is directly determined by means of a non linear but "convergence guaranteed" interpolation process to best fit the given data. A low-pass filter input reflection coefficient modeling example is included to exhibit the utilization of the proposed modeling method.
Scattering Transfer Matrix Factorization Based Synthesis of Resistively Terminated Lc Ladder Networks
(Kadir Has Üniversitesi, 2011) Aydoğar, Zafer; Şengül, Metin; Şengül, Metin
Bu yüksek lisans tezimde, direnç ile sonlandırılmış LC merdiven devrelerin sentezi için algoritmalr önerilmiştir. Bu algoritmalar saçılma transfer matrisi faktorizasyonuna dayanır. Alçak-geçiren, yüksek-geçiren, band-geçiren ve band-söndüren durumlar için dört algoritma geliştirilmiştir. Algoritmaların temelinde şu fikir yer almaktadır: İlk olarak, verilen saçılma tranfer matrisi kullanılarak bir sabit hesaplanır. Bu sabitin değerine göre çekilecek elemanın tipine karar verilir, daha sonra verilen saçılma transfer matrisi kullanılarak eleman değeri hesapanır. Bu elemana ait saçılma transfer matrisi ve verilen saçılma transfer matrisi kullanılarak, kalan devrenin saçılma transfer matrisi hesaplanır. Aynı işlem sonlandırma direncine ulaşıncaya kadar tekrarlanır. Bu problem, literatürde empedans / admitans parametreleri kullanılarak çizilmiştir. Bu tezde, saçılma parametreleri kullanılarak sentez problemi çözülmüş ve dolayısıyla alternatif bir sentez metodu geliştrilmiştir.
Design of Practical Matching Networks With Lumped Elements Via Modeling
(IEEE, 2007) Yarman, Sıddık Binboğa; Şengül, Metin; Şengül, Metin Y.; Kılınç, Ali
It is a common practice to utilize commercially available software tools to design matching networks for wireless communication systems. Most of these tools require a properly selected matching network topology with good initial element values. Therefore in this paper a practical method is presented to generate matching networks with initial element values. In the implementation process of the proposed method first the driving point immitance data for the matching network is obtained in a straight forward manner without optimization. Then it is modeled as a realizable bounded-real input reflection coefficient which in turn yields the desired matching network with reasonable element values. Eventually the initial design is improved by optimizing the performance of the matched system employing the commercially available computer-aided design (CAD) packages. An example is given to illustrate the utilization of the proposed method. It is shown that new method provides excellent results as a front-end when utilized together with CAD tools.
Synthesis of Lossless Ladder Networkswith Simple Lumped Elements Connected Viacommensurate Transmission Lines
(Istanbul Univ, Fac Engineering, 2010) Sengul, Metin; Şengül, Metin
An algorithm has been proposed, to synthesize low-pass, high-pass, band-pass and band-stop lossless ladder networks with simple lumped elements connected via commensurate transmission lines (Unit elements, UEs). First, the type of the element that will be extracted is determined from the given mixed-element network function. After obtaining element value, it is extracted, and the two-variable reflection function of the remaining mixed-element network is obtained. This process is repeated until extracting all the elements. For each network type, an example is included, to illustrate the implementation of the related algorithm.