Yazarlar

• Ertugrul, Mehmet(3)
• Kaya, Yunus(3)
• Hasar, Ugur C.(2)
• Ozturk, Gokhan(2)
• Barroso, Joaquim J.(1)
• Barroso, Joaquim Jose(1)
• Gurbuz, Tolga U.(1)
• Hasar, Ugur Cem(1)
• Izginli, Mucahit(1)
• Ozturk, Hamdullah(1)
• Ramahi, Omar M.(1)

• MakaleAçık Erişim2022Scopus SJRQ1/r/bayburt/11989
  Calibration-Free Time-Domain Free-Space Permittivity Extraction Technique

  Hasar, Ugur C.; Ozturk, Gokhan; Kaya, Yunus; Ertugrul, Mehmet

  A time-domain free-space technique has been proposed to extract relative permittivity ( _r ) and effective conductivity ( σ _e ) of low-loss dielectric samples using their metal- and air-backed calibration-free reflected powers. Numerical computations and 3-D electromagnetic simulations were performed to validate the method. A sensitivity analysis was carried out to examine its accuracy. Calibration-free time-domain free-space measurements over 1-12 GHz were conducted by VNA to extract _r and σ _e of polyethylene and polypropylene low-loss samples.

  AtıfScopus29·WoS28·OpenAlex29

  İncele
• MakaleYalnız künye2022Scopus SJRQ1/r/bayburt/10787
  Complex Permittivity and Thickness Evaluation of Low-Loss Dielectrics From Uncalibrated Free-Space Time-Domain Measurements

  Hasar, Ugur Cem; Kaya, Yunus; Ozturk, Hamdullah; Izginli, Mucahit; Barroso, Joaquim Jose; Ramahi, Omar M.; Ertugrul, Mehmet

  A free-space time-domain method is proposed to retrieve dielectric constant (epsilon r), conductivity (sigma e), and thickness (d) of metal-backed low-loss dielectric samples using calibration-independent reflected power peak measurements. Its algorithm is validated by numerical calculations and simulations (CST Microwave Studio) using a sine-modulated Gaussian window. A sensitivity analysis is followed to examine its performance considering the dependencies of reflected power peaks with respect to epsilon r and sigma e. Free-space time-domain measurements have been implemented after transforming frequency-domain measurements into time-domain ones to extract epsilon r, sigma e, and d of polypropylene, polyethylene, and polyoxymethylene samples.

  AtıfScopus48·WoS42·OpenAlex43

  İncele
• MakaleYalnız künye2021Scopus SJRQ1/r/bayburt/12150
  Graphical Method for Examining Complex Natural Frequencies of Dispersive Materials

  Hasar, Ugur C.; Ozturk, Gokhan; Barroso, Joaquim J.; Gurbuz, Tolga U.; Kaya, Yunus; Ertugrul, Mehmet

  A graphical method is extended to and applied for visual inspection of solution patterns (region of complex natural frequencies sₙ) in the complexs-plane for dispersive materials characterized by the Debye and Lorentz models. These patterns are in the form of exponential decay and C-shaped profiles for the Debye and Lorentz models, respectively. Their forms are observed to be affected (e.g., moving left/right) in different manners with a variation of dispersion parameters. This method, thanks to its visual inspection capability, can help in analyzing/synthesizing filters and frequency-selective surfaces.

  AtıfScopus6·WoS6·OpenAlex7

  İncele