Arama Sonuçları

Listeleniyor 1 - 6 / 6
  • Yayın
    A tunable inductance topology to realize frequency tunable matching networks and amplifiers
    (IEEE, 2013) Atilla, Doğu Çağdaş; Aydın, Çağatay; Köprü, Ramazan; Nesimoğlu, Tayfun; Yarman, Bekir Sıddık Binboğa
    Coverage of commercial communication standards such as GSM, UMTS, Wi-Fi and Wi-Max within a single transceiver chip is one of the most desired properties by wireless communication manufacturers. In this regard, communication companies are keenly interested in the design of high power amplifiers for broadband cellular communications to achieve this coverage. In this work, design of broadband tunable matching networks is investigated using Real Frequency Techniques. In practical applications, tunability is needed to compensate for the load impedance variations with environmental effects. In order to be able to work on sample structures, impedance transforming filters with proper topology are chosen and a broadband tunable matching network with a tunability strategy is developed. Eventually a broadband amplifier has been designed using the tunable inductor concept.
  • Yayın
    Computer aided darlington synthesis of an all purpose immittance function
    (Istanbul University, 2016) Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet; Köprü, Ramazan; Kumar, Narendra Senthil; Aydın, Çağatay; Atilla, Doğu Çağdaş; Chacko, Prakash
    This work is the continuation of our high precision immittance synthesis paper series introduced in IEEE TCAS-I. In the present manuscript, we modified the previously introduced high precision Bandpass LC-ladder 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. Finite frequency and RHP transmission zeros are extracted employing our newly introduced modified impedance and chain parameters based algorithms one by one. After each transmission zero extraction, remaining immittance function is corrected using parametric approach. It is shown that propsed high precision synthesis algorithms can synthesize immittance functions 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 matching networks over broadbands. Examples are presented to exhibit the usage of the newly proposed high precision synthesis algorithms.
  • Yayın
    Wideband bandpass filter design for X band horn antenna via numerical techniques
    (IEEE Computer Society, 2015) Köprü, Ramazan; Aydın, Çağatay; Atilla, Doğu Çağdaş; Kılınç, Sedat; Yarman, Bekir Sıddık Binboğa
    Design of an X band horn antenna and a wideband unit element microstrip bandpass filter (UEBPF) for this antenna are presented with satisfactory agreement between theoretical and simulation results. Numerical methods known as real frequency techniques (RFTs) have been utilized in Richards domain to yield optimum driving point Darlington input impedance function belonging to the UEBPF that enables a maximum RF power transmission between the designed horn antenna and an RF driving source. Using a high precision Richards immittance synthesis package in Matlab, characteristic impedance values of each UE, out of k number of commensurate (equal length) transmission lines forming the UEBPF, is extracted from the input impedance function. Theoretical design (Matlab of Mathworks Inc.) and simulation (ADS of Agilent Inc., HFSS of ANSYS Corp.) results are shown to be very promising and in a high degree of agreement with each other.
  • Yayın
    Transformerless bandpass matching network design for Y-Shaped monopole antenna
    (IEEE, 2015) Aydın, Çağatay; Atilla, Doğu Çağdaş; Karakuş, Cahit; Köprü, Ramazan; Yarman, Bekir Sıddık Binboğa
    In this paper, a transformerless bandpass matching network design procedure is presented. The Real Frequency Techniques are powerful numerical methods to design wideband lossless 2-port networks such that filters and matching networks. In these techniques, the value of the termination resistance of the designed network could not be yielded as 50 ohm by numerical package. Hence, a transformer is also required for 50 ohm termination which is not practical for high frequency applications. Also in this study a novel wideband monopole antenna is presented. The proposed antenna is consisting of two major elements; Y-shaped impedance matching plate and hemi-circular radiator. Moreover Y-shaped impedance matching plate connected to a feeding probe excites the suspended hemi-circular radiator via air gap. and its frequency band is expanded by using transformerless bandpass design procedure.
  • 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
    Wideband matching network design for a V-Shaped square monopole antenna using Real Frequency Technique
    (IEEE, 2013) Köprü, Ramazan; Aydın, Çağatay; Atilla, Doğu Çağdaş; Karakuş, Cahit; Yarman, Bekir Sıddık Binboğa
    In this paper, design and simulation of a wideband matching network for a broadband V-shaped square monopole antenna is presented. Matching network design is unavoidable in most cases even vital to facilitate a maximally flat power transfer gain for an antenna. In the work, the matching network design is done for a particular square monopole antenna with V-shaped coupling element that has essentially bandwidth increasing effect. The V-shaped antenna had been manufactured, tested and analyzed elaborately in a previous work. With this work, it is now equipped by a matching network. 'Real Frequency Technique' (RFT) is employed in matching network design.