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I C Hunter - One of the best experts on this subject based on the ideXlab platform.

  • substrate integrated waveguide Cavity Resonators for complex permittivity characterization of materials
    IEEE Transactions on Microwave Theory and Techniques, 2008
    Co-Authors: K Saeed, R D Pollard, I C Hunter
    Abstract:

    A novel planar substrate integrated waveguide Cavity resonator technique for measurement of complex permittivity is described, which has applications for dielectric measurement systems in the pharmaceutical industry. The high-Q resonant structure is a modernization of well-known measurement cells where the dielectric constant is deduced by Cavity perturbation from the shift in resonant frequency and the change in the Q factor. The method uses extremely small amounts of a broad range of materials for accurate characterization. The ease of fabrication, low cost, and potential for integration with many other components on the same substrate allows it to be used in a disposable manner.

Dimitrios Peroulis - One of the best experts on this subject based on the ideXlab platform.

  • ultra compact tunable filtering rat race coupler based on half mode siw evanescent mode Cavity Resonators
    IEEE Transactions on Microwave Theory and Techniques, 2018
    Co-Authors: Mohamed F Hagag, Michael D. Sinanis, Mohammad Abu Khater, Dimitrios Peroulis
    Abstract:

    In this paper, for the first time, an ultra-compact frequency-tunable filtering rat-race coupler based on half-mode evanescent-mode (EVA) Cavity Resonators is presented. Employing EVA Cavity Resonators in the coupler design yields attractive characteristics, such as a wide tuning range and a wide spurious-free range, while also adding filtering functionality to the device. The presented coupler is synthesized as a two pole bandpass filter using the coupling matrix method. Then, the coupling coefficients are mapped to a coupler topology. Design, simulations, and experimental validation are presented. The implemented rat-race coupler has a very compact size [ $0.14\lambda _{g}\times 0.14\lambda _{g} $ ( $\lambda _{g}$ at 885 MHz)] achieving a 92% miniaturization in the structure footprint compared to the conventional planar one. The coupler has an 86% tuning range ranging between 0.885–1.65 GHz. Throughout the tuning range, the coupler shows an equal power splitting ratio and filtering profile with a measured insertion loss and 3-dB fractional bandwidth between 5 and 4.2 dB and 6.8% and 8%, respectively. The measured isolation is better than 30 dB. In addition, the coupler has a measured spurious-free range of $10.2f_{o}$ (at the lowest frequency) to $5.45f_{o}$ (at the highest frequency).

  • V-band frequency reconfigurable Cavity-based bandpass filters
    2016 IEEE ACES International Conference on Wireless Information Technology and Systems (ICWITS) and Applied Computational Electromagnetics (ACES), 2016
    Co-Authors: Mahmoud Abdelfattah, Zhengan Yang, Dimitra Psychogiou, Dimitrios Peroulis
    Abstract:

    Two-pole and three-pole RF-MEMS-enabled tunable bandpass filters are demonstrated as the first all-silicon frequency reconfigurable Cavity filters operating in the V band. They are tuned by means of electrostatically-actuated corrugated MEMS diaphragms that are located on top of evanescent-mode Cavity Resonators. The two-pole filter exhibits tunable center frequency between 57.7 to 63 GHz with worst-case insertion loss (IL) of 2.8 dB and maximum actuation voltage of 140 V. The three-pole filter demonstrates tunable frequency between 61.9 to 65 GHz with a maximum actuation voltage of 150 V and IL better than 4.9 dB.

  • Silicon-micromachined spacers for UHF Cavity Resonators
    2015 28th IEEE International Conference on Micro Electro Mechanical Systems (MEMS), 2015
    Co-Authors: Dimitra Psychogiou, Michael D. Sinanis, Dimitrios Peroulis
    Abstract:

    This paper reports on a novel hybrid integration concept that enables the realization of high-quality (Q) factor, low-frequency coaxial Cavity Resonators with well-defined capacitive-loading and variable center frequency. It is based on a silicon-micromachined spacer that is mounted on top of a conventional CNC-machined metallic Cavity to functionalize the resonator's capacitance. For the first time, it is demonstrated that low-frequency Resonators with micrometer-scale gaps (10s of microns), relatively large Q-factor (459-505) and tunable response (18.5%) can be constructed without the need for post-fabrication tuning. To demonstrate these benefits, a resonator assembly was designed, built and experimentally tested at the UHF band and for a frequency tuning range between 1424-1711 MHz.

  • nano plasma tunable evanescent mode Cavity Resonators
    International Microwave Symposium, 2014
    Co-Authors: Abbas Semnani, Dimitrios Peroulis
    Abstract:

    Conventional tunning mechanisms for evanescent-mode Cavity Resonators include changing a gap size through MEMS-based structures. In this paper, for the first time, we propose a technique for adjusting the resonant frequency of these Resonators by using a nano-plasma region. For this aim, a sufficiently large DC field is applied which generates a nano-plasma layer inside the gap between the loading post and the top wall of the Cavity. The thickness as well as the electromagnetic characteristics of this plasma layer and consequently the capacitance of the resonator are controlled by varying the applied DC field. This technique is potentially simpler than mechanically changing the gap size. As a proof of principle, we consider a 50 GHz resonator whose resonant frequency decreases down to 34.6 GHz when the applied DC voltage goes up to 94 V.

  • Microwave Gas Breakdown in Tunable Evanescent-Mode Cavity Resonators
    IEEE Microwave and Wireless Components Letters, 2014
    Co-Authors: Abbas Semnani, Kenle Chen, Dimitrios Peroulis
    Abstract:

    Microwave gas breakdown in strongly-coupled evanescent-mode Cavity Resonators in atmospheric pressure and room temperature is investigated both numerically and experimentally. This high- Q resonator is widely tunable by changing the gap between its loading post and top wall. In this letter, we study the effect of different gap spacings on breakdown characteristics of this resonator. Good agreement is observed between measured breakdown powers and ones by plasma simulations for Resonators with gaps of 14.8-51.2 μm, working in the 6-8.25 GHz frequency range with input breakdown power in the range of 45-48 dBm.

K. S. Tan - One of the best experts on this subject based on the ideXlab platform.

  • Design of a substrate integrated waveguide bandstop filter using dual-radial Cavity Resonators
    2014 IEEE REGION 10 SYMPOSIUM, 2014
    Co-Authors: M. N. Husain, G. S. Tan, K. S. Tan
    Abstract:

    Dual-radial Cavity Resonators are proposed to design SIW bandstop filter. The bandstop filter is designed by coupling two radial Cavity Resonators to the SIW line. The designed bandstop filter operates at a centre frequency of 9GHz and implemented on RT/Duriod 4350 substrate with a thickness of 0.508mm and relative permittivity of 3.66. Two single Cavity resonator bandstop filters are designed first and had 3-dB FBWs of around 500MHz and attenuation of −19dB. After that, dual-Cavity Resonators bandstop filter is designed and had 3-dB FBWs of 525MHz and attenuation of −45dB.

  • High Performance Substrate Integrated Waveguide Bandstop Filter using Dual-radial Cavity Resonator
    Journal of Telecommunication Electronic and Computer Engineering, 2014
    Co-Authors: G. S. Tan, M. N. Husain, K. S. Tan
    Abstract:

    A SIW bandstop filter is designed by coupling two Cavity Resonators to the SIW line. Dual-radial Cavity Resonators are proposed to design the SIW bandstop filter. Two single radial Cavity resonator SIW bandstop filter are designed first. After that, a dual-radial Cavity resonator SIW bandstop filter is designed based on the two single radial Cavity resonator SIW bandstop filter. The designed bandstop filter operates at X-band frequency with a stopband from 8.7GHz to 9.2GHz, and it is implemented on RO4350B substrate with a thickness of 0.508mm. An insertion loss of less than 3dB is achieved, and the bandstop filter have a sharp roll of with attenuation of -34dB. This bandstop filter can be applied in the radar system

  • Rectangular circular and radial Cavity resonator substrate integrated waveguide bandstop filters
    2013 IEEE Student Conference on Research and Developement, 2013
    Co-Authors: M. N. Husain, G. S. Tan, K. S. Tan
    Abstract:

    A bandstop filter utilizing Substrate Integrated Waveguide Cavity Resonators coupled to the SIW line is presented in this paper. Prior to this research, rectangular Cavity resonator was utilized to provide a bandstop response. In this paper, circular and radial Cavity Resonators are proposed to provide a bandstop response. The filters are designed to operate at X-band and implemented on RT/Duriod 4350 substrate with a thickness of 0.508mm. The simulated results of the circular and radial bandstop filters have shown good bandstop responses and thus useful in microwave bandstop filter design.

K Saeed - One of the best experts on this subject based on the ideXlab platform.

  • substrate integrated waveguide Cavity Resonators for complex permittivity characterization of materials
    IEEE Transactions on Microwave Theory and Techniques, 2008
    Co-Authors: K Saeed, R D Pollard, I C Hunter
    Abstract:

    A novel planar substrate integrated waveguide Cavity resonator technique for measurement of complex permittivity is described, which has applications for dielectric measurement systems in the pharmaceutical industry. The high-Q resonant structure is a modernization of well-known measurement cells where the dielectric constant is deduced by Cavity perturbation from the shift in resonant frequency and the change in the Q factor. The method uses extremely small amounts of a broad range of materials for accurate characterization. The ease of fabrication, low cost, and potential for integration with many other components on the same substrate allows it to be used in a disposable manner.

Kamran Entesari - One of the best experts on this subject based on the ideXlab platform.

  • Ultra-Miniature SIW Cavity Resonators and Filters
    IEEE Transactions on Microwave Theory and Techniques, 2015
    Co-Authors: Alireza Pourghorban Saghati, Kamran Entesari
    Abstract:

    This paper presents ultra-miniature substrate integrated waveguide (SIW) Cavity Resonators, and filters by employing ramp-shaped slots as interdigital capacitors (IDCs) to force the structure to operate in the first negative-order resonance mode. Additionally, a metal patch in the middle metal layer along with disconnected vias is used to increase the equivalent series capacitance of the resonator and accordingly the miniaturization factor. By applying this method to half-mode SIW (HMSIW) and quarter-mode SIW (QMSIW) Resonators, 90%, and 95% of miniaturization is achieved, respectively, compared to conventional full-mode SIW Resonators. Afterwards, a two-pole bandpass filter is proposed based on the presented QMSIW resonator. Also, by using a combination of HMSIW and QMSIW ultra-miniature Resonators, two trisection filters with a controllable transmission zero on either side of the passband are presented. To the best of authors' knowledge, this is the first disclosure of simultaneous use of HMSIW and QMSIW Resonators to achieve asymmetric filter response with an ultra-compact size.