Arama Sonuçları

Listeleniyor 1 - 10 / 11
  • Yayın
    Design and implementation of wideband microwave amplifiers based on Normalized Gain Function
    (Institute of Electrical and Electronics Engineers Inc., 2014) Köprü, Ramazan; Kılınç, Sedat; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this work, we introduce the design and implementation of wideband microwave amplifiers based on "Normalized Gain Function (NGF)" method. Normalized Gain Function is defined as the ratio of desired shape or frequency response of the gain function of the amplifier to be designed and shape of the transistor forward gain function. Synthesis of input/output matching networks (IMN/OMN) of the amplifier require target gain curves as the functions of normalized gain function to be tracked in two sequential nonlinear optimization processes. A prototype low power amplifier circuit is produced and measured to show the usability of the design approach.
  • Yayın
    A broadband microwave amplifier design by means of immittance based data modelling tool
    (IEEE, 2002) Kılınç, Ali; Pınarbaşı, Hacı; Şengül, Metin; Yarman, Bekir 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.
  • Yayın
    Mixed element wideband microwave amplifier design via simplified real frequency technique
    (IEEE Computer Society, 2014) Kılınç, Sedat; Köprü, Ramazan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this study, we illustrate the design and implementation of a wideband microwave small-signal amplifier composed of mixed elements. The design is based on Simplified Real Frequency Technique (SRFT). A design of low power amplifier circuit is completed and its simulations are performed in success. The circuit is designed with lumped elements, however, some of the lumped elements are converted to distributed elements for their convenience in production. In this way, a mixed element wideband microwave amplifier comprised of input/output matching networks with lumped and distributed elements has been formed. Layout work and also post layout simulation is given with satisfying results.
  • Yayın
    Computer aided high precision Darlington synthesis for real frequency matching
    (Institute of Electrical and Electronics Engineers Inc, 2014) Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet; Köprü, Ramazan; Aydın, Çağatay; Atilla, Doğu Çağdaş
    In this work, we introduce a high precision synthesis algorithm to include the extraction of finite frequency and right half plane (RHP) transmission zeros of an impedance function as Brune/Darlington Type-C sections. After each transmission zero extraction, remaining immittance function is corrected using a parametric approach. It is shown that proposed high precision synthesis algorithm can synthesize immittance functions up to 40 reactive elements with accumulated relative error in the order of 10-1. The high precision synthesis package is integrated with the real frequency techniques to design matching networks over broadbands. Examples are presented to exhibit the usage of the proposed high precision synthesis algorithm.
  • Yayın
    A high precision Cascade Synthesis Technique for real frequency matching involving Brune and Darlington Type-C sections
    (IEEE, 2014) Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet; Köprü, Ramazan; Aydın, Çağatay; Atilla, Doğu Çağdaş
    In this work, we introduce a high precision cascade synthesis technique for lossless matching networks involving Brune and Darlington Type-C sections. In the present manuscript, we generalized our previously introduced high precision LCladder synthesis algorithm to include the extraction of finite real frequency and right half plane (RHP) transmission zeros of an impedance function as Brune and Darlington Type-C sections respectively. In the modified synthesis algorithm, after each finite frequency and RHP transmission zero extraction, remaining immittance function is corrected using a parametric approach. It is shown that proposed high precision algorithm can synthesize immittance functions of up to 40 reactive elements with accumulated relative error in the order of 10(-1). The modified high precision synthesis package is developed in MatLab environment and it is integrated with the real frequency techniques to design high complexity matching networks over broad bands. An illustrative example is presented to exhibit the usage of the proposed high precision synthesis algorithm.
  • Yayın
    Microwave amplifier design for mobile communication via immittance data modelling
    (IEEE, 2003) Kılınç, Ali; Pınarbaşı, Hacı; Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet
    In this paper, a practical broadband microwave amplifier design algorithm based on immittance data modelling is presented. 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-modeling 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 wideband microwave amplifier over a wide frequency band. It is expected that the proposed design algorithm will find applications in the design of microwave amplifiers put on MMIC for mobile communication.
  • Yayın
    FSRFT - Fast simplified real frequency technique via selective target data approach for broadband double matching
    (IEEE, 2017-02) Köprü, Ramazan
    This brief introduces a broadband double-matching (DM) solver called fast simplified real frequency technique (FSRFT). FSRFT is essentially a greatly accelerated variant of the well-known classical simplified real frequency technique (SRFT). The basic idea that turns the classical SRFT into a 'fast' SRFT relies on two main approaches: the selective target data approach (STDA) and the constraint optimization approach (COA). STDA constructs an optimization target data set formed of only critically selected target data whose element number is equal to or slightly greater than the order of the system unknowns n plus 1, {n}+1. In order to exhibit speed performance comparison between SRFT and FSRFT, an example design is considered. An exemplary DM problem, dealing with an {n}=6th order low-pass Chebyshev-type equalizer design to match the given generator and load impedances, has been solved by SRFT within 29 s using 90 target data in a typical computer - e.g., Intel 2.20-GHz i7 CPU with 8-GB RAM. On the other hand, the same problem has been solved by the newly proposed FSRFT within only 0.6 s using only n+1=7 critically selected target data in the same computer. FSRFT introduced herein works in any domain, i.e., lumped, distributed, and mixed.
  • Yayın
    Design and realization of wideband matching networks in Richards domain
    (Institute of Electrical and Electronics Engineers Inc, 2014) Kılınç, Sedat; Köprü, Ramazan; Yarman, Bekir Sıddık Binboğa
    A broadband matching network design is given with its simulation and prototype measurement results. The circuit contains certain number of cascaded unit-elements (UEs) and open-stubs which behave as Richards capacitors. Richards domain driving point immittance (impedance or admittance) function of the network is obtained utilizing the Real Frequency Direct Computational Technique (RFDCT). Synthesis of the immittance function via "high precision Richards synthesis package" yields the characteristic impedances of microstrip unit-elements, open and short stubs. Kuroda transforms are used to convert short-stubs to open-stubs due to their difficulties in manufacturing. Theoretical design, simulation and measurements are in a good agreement.
  • Yayın
    Reflectance data model with mixed lumped and distributed elements for wireless communication systems
    (IEEE, 2005) Yarman, Bekir Sıddık Binboğa; Şengül, Metin; Kılınç, Ali; Aksen, Ahmet
    In this paper, a new method is presented to model the given reflectance data obtained from a "passive one-port physical device", as a lossless two port consists of lumped and distributed elements. Basis of the new method rests on the interpolation of the given data as a realizable bounded-real (BR) reflection function in two variables. The desired circuit model is then obtained as the result of the synthesis of this function in two kinds of elements; namely, distributed and lumped circuit elements. An algorithm is presented to generate the circuit model step by step and an example is also included to exhibit the utilization of the new modeling algorithm.
  • Yayın
    High precision LC ladder synthesis part ıı: Immittance synthesis with transmission zeros at DC and infinity
    (IEEE-INST Electrical Electronics Engineers Inc, 2013-10) Yarman, Bekir Sıddık Binboğa; Kılınç, Ali
    In this paper, a novel, high precision bandpass LC ladder synthesis algorithm is presented. The new algorithm directly works on the rational form of a positive real driving point input immittance F(p) = a(p)/b(p) which describes a bandpass LC ladder network in resistive termination. In the new method, firstly, poles at p = 0 are removed from F(p), then remaining poles at infinity are extracted. After each pole extraction, coefficients of the polynomial a(p) and b(p) are refined employing the parametric approach to yield an exact bandpass LC ladder which in turn prevents the accumulation of the numerical errors in the course of synthesis. Thus, at the end of synthesis process, a bandpass LC ladder is obtained with high numerical precision.