Polarization-Insensitive Single-/Dual-Band Tunable Absorber With Independent Tuning in Wide Frequency Range

In this work, we proposed a flexible broadband metamaterial perfect absorber (FBMPA) by exploiting a pasted conductive-graphene ink on a polyimide substrate. For the flat FBMPA, an absorption over 90% was found to cover a wide frequency range (from 7.88 to 18.01 GHz). The high-absorption feature was polarization-insensitive and regarded as stable with respect to the oblique incidence up to 30 degrees of electromagnetic wave. The high absorption was maintained well even when the absorber was wrapped. That is, the FBMPA was attached to cylindrical surfaces (with the varying radius from 4 to 50 cm). For both flat and curved states, the absorption mechanism was explained by the perfect impedance matching and the dielectric loss of the proposed absorber. Our work provides the groundwork for the commercialization of future meta-devices such as sensors, optical filters/switchers, photodetectors, and energy converters.

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Compact left-handed dual-band filters based on shundted stub resonators

Facta universitatis - series Electronics and Energetics ◽

10.2298/fuee1904571r ◽

2019 ◽

Vol 32 (4) ◽

pp. 571-579

Author(s):

Vasa Radonic ◽

Vesna Crnojevic-Bengin

Keyword(s):

Equivalent Circuit ◽

Superposition Principle ◽

Equivalent Circuit Model ◽

Wide Frequency Range ◽

Dual Band ◽

Geometrical Parameters ◽

Frequency Range ◽

Frequency Bands ◽

Left Handed ◽

Spurious Response

In this paper, super-compact microstrip dual-band resonator is presented, designed using the superposition of two simple left-handed (LH) resonators with single shunt stub. The proposed resonator exhibits spurious response in wide frequency range and therefore allows construction of dual-band filters using the superposition principle. The equivalent circuit model of the proposed resonator is crated and the influence of different geometrical parameters to the performances of the resonator are analyzed in details. As an examples, two dual-band filters that operate simultaneously at the WiMAX frequency bands are designed.

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A compact dual band-notched SWB antenna with high bandwidth dimension ratio

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078720000793 ◽

2020 ◽

pp. 1-7

Author(s):

Aliakbar Dastranj ◽

Ghazaleh Lari ◽

Mosayeb Bornapour

Keyword(s):

Time Domain ◽

Coplanar Waveguide ◽

Ground Plane ◽

Wide Frequency Range ◽

Dual Band ◽

Potential Candidate ◽

Frequency Range ◽

High Bandwidth ◽

Dimension Ratio ◽

Swb Applications

Abstract In this research, a compact dual band-notched (DBN) super-wideband (SWB) coplanar waveguide-fed antenna with high bandwidth (BW) dimension ratio of 7427.4 has been presented. The proposed antenna covers a very wide frequency range from 2.8 to 40 GHz (BW ratio of 14.28:1) with |S11|<−10 dB. The overall antenna size is 20 × 14 × 1.6 mm3 which consists of an FR4 substrate with a dielectric constant of 4.4, a shovel-shaped radiating patch and the symmetric stair-shaped ground plane. The DBN characteristics are achieved by employing a pair of C-shaped and circular slots on its shovel-shaped radiating patch to reject the interferences caused by two WiMAX (3.7–4.7 GHz) and WLAN (5.7–6.4 GHz) bands. The notched frequency bands can be controlled by changing the radii of slots. The SWB property of the antenna is obtained by using a symmetric stair-shaped ground plane and also a shovel-shaped radiating patch. The measured results of the fabricated prototype in frequency-and time-domain are also presented and compared with the numerical results. The results indicate that the antenna has good performance over the entire operating BW (173.8%) which makes it very potential candidate for modern SWB applications.

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