January 15, 2018

Low profile concentric distributed resonators and filters

  • Bulja S.
  • Doumanis E.
  • Kozlov D.

In this paper we introduce a new family of low-profile and high quality factor distributed resonators, termed concentric distributed resonators. The study of the proposed resonators commences by the investigation of its key parameters, such as frequency of operation, quality factor and maximum electric fields as a function of the number of individual resonant elements along the periphery of concentric circles. In one case, it is shown that the height of the entire resonator can be kept as low as 3.5 mm, while still achieving a quality factor of about 1,400. As an experimental verification of the proposed resonators, a 3-pole filter is designed to operate at a frequency of 1.8 GHz with an absolute bandwidth of 40 MHz, equivalent to 2.22 %. Each resonant chamber of the presented filter consists of 25 individual resonant elements arranged in an interdigitated fashion along the circumference of three concentric rings. The internal height of the filter (5 mm) is among the lowest reported in the literature.

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© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Uber is a popular ride-sharing application that matches people who need a ride (or riders) with drivers who are willing to provide it using their personal vehicles. Despite its growing popularity, there exist ...

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© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Recent studies in social media spam and automation provide anecdotal argumentation of the rise of a new generation of spambots, so-called social spambots. Here, for the first time, we extensively study this novel ...