Arama Sonuçları

Listeleniyor 1 - 7 / 7
  • 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 novel method to design wideband power amplifier for wireless communication
    (IEEE, 2013) Köprü, Ramazan; Kuntman, Hulusi Hakan; Yarman, Bekir Sıddık Binboğa
    A new approach is presented to design microwave amplifiers to deliver maximum output power using Simplified Real Frequency Technique (SRFT). Proposed method tracks the maximum stable gain (MSG) curve of the active device (BJT, FET etc.) under consideration. Maximum Stable Gain Amplifier (MSGA) possesses higher gain than that of the constant or Flat Gain Amplifier (FGA) along the operating frequency band. Compared to FGA, it is this feature that makes MSGA high efficiency and low DC power consumption amplifier. Employing the proposed design method, a MSG power amplifier is constructed over the frequency band of 800-5200 MHz which can be utilized for GSM, UMTS, Wi-Fi and Wi-MAX applications.
  • 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
    Unit element bandpass filter design via simplified real frequency technique for UWB microstrip patch antenna
    (IEEE Computer Society, 2014) Köprü, Ramazan; Kılınç, Sedat; Aksen, Ahmet; Yarman, Bekir Sıddık Binboğa
    Design of a UWB (Ultra Wideband) microstrip patch antenna to operate in the first channel of the UWB standard and a bandpass (BP) UE (Unit Element) microstrip filter (BPUEF) for this antenna are studied and presented with promising experimental results. A typical UE BP filter is a lossless 2-port network which is formed with certain number of cascade connected commensurate transmission lines. Based on the simplified real frequency technique (SRFT) in Richards domain, driving point Darlington impedance function of the BPUEF is obtained via optimization such that optimum power transfer would be possible between a PA (power amplifier) and the antenna. Using the UE synthesis, characteristic impedance values of each UE is extracted from the input impedance function. Theoretical design (Matlab), simulation (ADS, Agilent Inc.) and the measurements are shown to be in a high degree of agreement.
  • 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.
  • Yayın
    Broadband matching of PA-To-PCB interconnection for X-band wireless power transfer
    (Institute of Electrical and Electronics Engineers Inc., 2019-08) Köprü, Ramazan
    Design and simulation of a microwave wideband microstrip unit element bandpass matching network is presented, potential use might be a broadband WPT (microwave wireless power transfer) application in X-band frequencies (8-12 GHz). The source of the main energy can be wind, fossil, tidal, solar, nuclear, hydro etc. and the main energy can be converted from DC to microwave energy which then can be transmitted via the proposed WPT circuit towards a few or a network of a multiple microwave harvester receivers located at a near or far field from the main source. In the work, a bandpass matching network (BPMN) composed of microstrip "unit elements (UEs)" is designed to operate along the whole X-band (8-12 GHz). Designed BPMN is excited by an X-band commercial PA (power amplifier) MMIC (monolithic microwave integrated circuit) packaged chip, and it is loaded by an X-band microstrip patch antenna. A bond wire soldered between the RF output pad of MMIC chip and the input pad of the BPMN has an equivalent LC parasitic impedance assumed to be the generator complex impedance that must be compensated in a typical matching problem. SRFT (simplified real frequency technique) is used in the design of the matching network that compensates the effect of bond wire and very good agreement found between the theoretical design and simulations done in MWO (AWR).