Arama Sonuçları

Listeleniyor 1 - 5 / 5
  • 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
    A design technique of 50 Ω terminated bandpass matching network and its implementation to a Y-shaped monopole antenna matching
    (Springer, 2016-12) Aydın, Çağatay; Atilla, Doğu Çağdaş; Köprü, Ramazan; Kılınç, Sedat; Karakuş, Cahit; Yarman, Bekir Sıddık Binboğa
    In this paper, a 50 Ω terminated or in other words transformerless bandpass matching network design methodology and an implementation example are presented. The real frequency techniques are powerful numerical methods to design wideband lossless two-port networks such as filters, matching networks and amplifiers. In these techniques, the value of the termination resistance of the designed network could not be yielded as 50 Ω by numerical package. Hence, a transformer is also required for 50 Ω termination which is not practical for high frequency applications. By employing the proposed procedure, it is guaranteed to obtain transformerless bandpass matching network. Also in this study a wideband suspended monopole antenna is examined. The proposed antenna consists 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. Consequently, a transformerless bandpass matching network is designed to filter and expand the operational frequency bandwidth of the proposed antenna. It has been observed that ideal circuit and the layout of the matching network simulation have good agreement.
  • Yayın
    An eclectic approach to design tunable amplifiers
    (Wiley-Blackwell, 2013-07) Nesimoğlu, Tayfun; Aydın, Çağatay; Atilla, Doğu Çağdaş; Köprü, Ramazan; Yarman, Bekir Sıddık Binboğa
    Broadband amplifiers that can accommodate commercial communication standards such as GSM, UMTS, Wi-Fi, and Wi-Max are extremely important for radio equipment manufacturers. To achieve this coverage, the amplifier should provide high gain and efficiency over a band from 800 to 5200 MHz. Although there are transistor devices that have cut-off frequencies well over these frequencies, amplifiers covering such a broad-bandwidth are difficult to design due to the requirement of broadband matching networks. In this work, design of broadband tunable matching networks is investigated using Real Frequency Direct Computational Technique (RF-DCT). In order to be able to work on sample structures, impedance transforming filters are chosen and a broadband tunable matching network has been designed. Implementation of tunable inductors is investigated and the performance of a tunable matching network using tunable inductors and capacitors is demonstrated. Eventually a broadband frequency tunable amplifier has been designed using the tunable inductor concept.
  • Yayın
    Ultra wideband matching network design for a V-shaped square planar monopole antenna
    (Cambridge University Press, 2014-12) Köprü, Ramazan; Kılınç, Sedat; Aydın, Çağatay; Atilla, Doğu Çağdaş; Karakuş, Cahit; Yarman, Bekir Sıddık Binboğa
    In this paper, design, manufacture, and measurement of a wideband matching network for a broadband V-shaped square planar monopole antenna (V-SPMA) 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, a bandpass matching network (BPMN) design is done for a particular square monopole antenna with V-shaped coupling element that has essentially bandwidth increasing effect. Designed BPMN and the antenna forms a VSPMA-BPMN matched antenna structure. "real frequency technique" is employed in the BPMN design. BPMN prototype circuit has been constructed on an FR4 laminate with commercial microwave chip inductors and capacitors. Vector network analyzer gain and reflectance measurements of the matched antenna structure have shown highly compatible results to those of the theoretical design simulations along the passband (similar to 0.8-4.7 GHz). Furthermore, newly proposed distributed capacitor-resistor lossy model for microstrip lines used in the BPMN circuit have exhibited that it can successfully mimic the measured gain and reflectance performance of the matched structure in passband and even in stopband upto 8 GHz. Designed structure can be utilized as a one single wideband broadcasting medium suitable for many communication standards such as GSM, 3G, and Wi-Fi.
  • 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.