Arama Sonuçları

Listeleniyor 1 - 10 / 15
  • Yayın
    Design of multiband matching ladders without mutual coupling using parametric representation of Brune functions
    (John Wiley and Sons Inc, 2020-10-01) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this study, a semianalytical method for the design of mutual coupling free multiband matching networks is introduced. A new parametric representation of Brune functions is used for the construction of multiband ladder network topologies without mutual induction. The method involves the use of Fujisawa's constraints for low pass ladders having finite transmission zeros, in a parametric representation of driving point impedance function resulting in mutual inductance free Brune sections. The developed parametric representation is incorporated with Real Frequency Techniques to design matching networks with a plurality of pass bands. Several illustrative design examples are presented to validate the method.
  • Yayın
    Dual band matching network design via real frequency technique by mapping from a band pass prototype
    (IEEE, 2016) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this study, a new method of design for dual band matching network is presented. A transformer-less Band Pass (BP) prototype matching network is synthesized with well-known Simplified Real Frequency Technique (SRFT) via cascaded combination of Low Pass (LP) and High Pass (HP) sections and optimized under LP to BP frequency transformation to create dual band response. Scattering parameters based descriptive functions of transformer-less BP prototype network is obtained. Dual band response is derived via frequency mapping on the produced BP prototype network. The new method combines several advantages both in design and realization step. The application of this method is discussed with sequential transformation based approach. A dual band matching network design for a PIFA antenna is presented. By using this method dual band characteristic is derived with only one step application of frequency mapping which let use to have more practical realizations.
  • Yayın
    Multiband matching network design via transformation based real frequency approach
    (IEEE, 2016) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this paper, a new method is presented for multiband matching network design. Low pass to band pass (LP-BP) frequency transformation is incorporated with the parametric Real Frequency Technique (RFT) for creating multiband network functions. In the new parametric approach, the poles of a low pass type impedance function are optimized under LP-BP transformation, for multiband matching of complex terminations. The resultant matching network is realized with resonance sections yielding multiband transducer power gain (TPG) characteristic.
  • Yayın
    Dual band filter design for GSM bands using frequency mapping and real frequency technique
    (IEEE, 2018) Yıldız, Serkan; Kılınç, Sedat; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this study, dual band frequency mapping is incorporated with Real Frequency Technique to design a dual band filter for GSM900 and GSM1800/UMTS bands. The proposed real frequency design technique (RFT) involves a parametric representation of input impedance of filter and the use of a dual band (DB) frequency mapping. A direct DB frequency mapping from low pass proto-type network is utilized along with the design and optimization of a low pass prototype network. Microstrip implementation of the designed filter and measurement results of the design are presented.
  • Yayın
    Multiband and concurrent matching network design via brune sections
    (IEEE, 2017) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    A general multiband matching network design methodology for complex load impedance terminations is presented. In the proposed approach, Real Frequency Techniques (RFT) are used to define and optimize the multiband matching network. In the characterization of the multiband network, multiple notch bands are obtained by the employment of finite transmission zeros (FTZ) in the transfer function. Brune section realization of finite transmission zeros and the associated coupled coil free realizations are discussed. A triple band matching network design for a triple band Sierpinski antenna load is presented to illustrate the performance of the proposed approach.
  • Yayın
    A real frequency approach to describe lossless two-ports formed with mixed lumped and distributed elements
    (Urban & Fischer Verlag, 2001) Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    The design of microwave filters, matching networks, amplifiers, that Is the "Broadband Networks" with mixed lossless lumped and distributed elements, has been a significant concern of the circuit theoreticians of the field. Yet, there has been no complete practical solution Introduced In the literature so far. In this paper, an attempt has been made to design broadband networks constructed with a cascade connection of low pass LC ladders connected with commensurate transmission lines. The new design procedure Is based on the two-variable description of the Simplified Real Frequency Technique. Up to five mixed-elements explicit equations are given to describe some selected network topologies. In general, synthesis Is carried out employing a decomposition technique first Introduced by Alfred Fettwels. A "Double Matching Design" example is presented to exhibit the merits and the application of the new approach.
  • Yayın
    Quad-band matching network design with real frequency technique employing frequency transformation
    (IEEE, 2017) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    In this study, a piecewise frequency transformation is presented for quad-band (QB) matching network design. The real frequency direct computational technique RFDCT is incorporated with the generated QB transformation. The proposed approach employs three sequential application of low-pass (LP) to band pass (BP) transformation. Transformation parameters are derived by using a direct LP to QB mapping scheme. RFDCT is used to find the optimum element values of a pre-defined transformer free matching network topology within a nonlinear iteration routine which incorporates the QB transformation. For assigned quad pass-bands, the parameters of QB transformation are also optimized to improve transducer power gain (TPG) of the matching network. A quad-band matching network design example is given to illustrate application of the proposed method.
  • Yayın
    Low pass filter design with improved stop-band suppression and synthesis with transformer-free ladders
    (John Wiley and Sons Inc, 2021-09) Yıldız, Serkan; Aksen, Ahmet; Kılınç, Sedat; Yarman, Bekir Sıddık Binboğa
    A new method to design transformer-free low pass (LP) ladder network with improved stop-band suppression performance is introduced. The parametric representation of back-end impedance of LP filter network is established with minimum impedance part and a Foster reactance part. The constructed impedance function is optimized by using real frequency technique. It has been shown that the proposed method provides LP filters which have superior stop-band suppression in comparison with classical transfer function-based filters with same complexity. The synthesis of the LP filter is obtained with the proposed element extraction procedure and resulted with fully realizable network elements in ladder form. An LP filter design and application by employing the proposed technique is provided. The measurement results of the prototyped filter are presented.
  • Yayın
    RFT Based multiband matching network design with foster resonance sections
    (IEEE, 2015) Yıldız, Serkan; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    A new method for a multi band matching network design is introduced in this paper. Foster resonance sections are used to create transmission zeros. This effect brings gain degradation at Transducer Power Gain (TPG) of the matching circuit at assigned frequencies of resonance sections. Single matching problem is concerned. It has been shown that proposed method gives good control on creating multiband characteristics.
  • 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.