Switchable UWB Antenna with defected ground plane

This research article describes a technique for realizing wideband dual notched functionality in an ultra-wideband (UWB) antenna array based on metamaterial and electromagnetic bandgap (EBG) techniques. For comparison purposes, a reference antenna array was initially designed comprising hexagonal patches that are interconnected to each other. The array was fabricated on standard FR-4 substrate with thickness of 0.8 mm. The reference antenna exhibited an average gain of 1.5 dBi across 5.25–10.1 GHz. To improve the array’s impedance bandwidth for application in UWB systems metamaterial (MTM) characteristics were applied it. This involved embedding hexagonal slots in patch and shorting the patch to the ground-plane with metallic via. This essentially transformed the antenna to a composite right/left-handed structure that behaved like series left-handed capacitance and shunt left-handed inductance. The proposed MTM antenna array now operated over a much wider frequency range (2–12 GHz) with average gain of 5 dBi. Notched band functionality was incorporated in the proposed array to eliminate unwanted interference signals from other wireless communications systems that coexist inside the UWB spectrum. This was achieved by introducing electromagnetic bandgap in the array by etching circular slots on the ground-plane that are aligned underneath each patch and interconnecting microstrip-line in the array. The proposed techniques had no effect on the dimensions of the antenna array (20 mm × 20 mm × 0.87 mm). The results presented confirm dual-band rejection at the wireless local area network (WLAN) band (5.15–5.825 GHz) and X-band satellite downlink communication band (7.10–7.76 GHz). Compared to other dual notched band designs previously published the footprint of the proposed technique is smaller and its rejection notches completely cover the bandwidth of interfering signals.

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Quad-Band multi-polarized antenna with modified electric-inductive−capacitive resonator

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078721000106 ◽

2021 ◽

pp. 1-12

Author(s):

Ghanshyam Singh ◽

Binod Kumar Kanaujia ◽

Vijay Kumar Pandey ◽

Sachin Kumar

Keyword(s):

Communication Systems ◽

Ground Plane ◽

Axial Ratio ◽

Antenna Design ◽

Planar Antenna ◽

Rectangular Slot ◽

Printed Circuits ◽

Rectangular Patch ◽

Easy Integration ◽

Defected Ground Plane

Abstract A compact circularly polarized (CP) patch antenna is presented for modern communication systems. The prospective antenna consists of a microstrip-line inset-fed rectangular patch and a defected ground plane. A rotated rectangular slot and a modified electric-inductive-capacitive (m-ELC) resonator are introduced in the patch and the ground plane to achieve multiband behaviour. A corner of the radiating patch is truncated and an arrow-shaped stub is introduced for generating circular polarization. The physical area of the substrate is 0.26λ0 × 0.22λ0, and the radiator size is 0.16λ0 × 0.14λ0, where λ0 is the free-space wavelength estimated at the lowest frequency. The measured (S11≤-10 dB) bandwidths of the antenna are 80 MHz (3.58%) at 2.23 GHz, 75 MHz (2.64%) at 2.84 GHz, 80 MHz (2.50%) at 3.19 GHz, and 70 MHz (1.82%) at 3.83 GHz. The measured 3-dB axial ratio bandwidths are 40 MHz (1.41%), 100 MHz (3.12%), and 60 MHz (1.57%) at 2.84, 3.20 and 3.82 GHz, respectively. The proposed planar antenna design does not need dual-feed or multi-layered patches for achieving multiple CP bands. It offers easy integration with the printed circuits of the communication systems.

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Design of a compact UWB antenna with a partial ground plane on epoxy woven glass material

Science and Engineering of Composite Materials ◽

10.1515/secm-2014-0297 ◽

2017 ◽

Vol 24 (1) ◽

pp. 73-79

Author(s):

Md. Moinul Islam ◽

Mohammad Tariqul Islam ◽

Mohammad Rashed Iqbal Faruque ◽

Rabah W. Aldhaheri ◽

Md. Samsuzzaman

Keyword(s):

Dielectric Material ◽

Ground Plane ◽

Ultra Wideband ◽

Design Parameters ◽

Uwb Antenna ◽

Glass Material ◽

Measurement Results ◽

Good Term ◽

Parametric Analyses ◽

Uwb Applications

AbstractA compact ultra-wideband (UWB) antenna is presented in this paper with a partial ground plane on epoxy woven glass material. The study is discussed to comprehend the effects of various design parameters with explicit parametric analyses. The overall antenna dimension is 0.22×0.26×0.016 λ. A prototype is made on epoxide woven glass fabric dielectric material of 1.6 mm thickness. The measured results point out that the reported antenna belongs to a wide bandwidth comprehending from 3 GHz to more than 11 GHz with VSWR<2. It has a peak gain of 5.52 dBi, where 3.98 dBi is the average gain. Nearly omnidirectional radiation patterns are observed within the operating frequency bands. A good term exists between simulation and measurement results, which lead the reported antenna to be an appropriate candidate for UWB applications.

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MICS/ISM Meander-Line Microstrip Antenna Encapsulated in Oblong-Shaped Pod for Gastrointestinal Tract Diagnosis

Sensors ◽

10.3390/s21113897 ◽

2021 ◽

Vol 21 (11) ◽

pp. 3897

Author(s):

Supakit Kawdungta ◽

Akkarat Boonpoonga ◽

Chuwong Phongcharoenpanich

Keyword(s):

Gastrointestinal Tract ◽

Microstrip Antenna ◽

Ground Plane ◽

Liquid Mixtures ◽

Dielectric Constants ◽

Antenna Structure ◽

Antenna Miniaturization ◽

Measured Impedance ◽

Meander Line ◽

Defected Ground Plane

In light of the growth in demand for multiband antennas for medical applications, this research proposes a MICS/ISM meander-line microstrip antenna encapsulated in an oblong-shaped pod for use in diagnoses of the gastrointestinal tract. The proposed antenna is operable in the Medical Implant Communication System (MICS) and the Industrial, Scientific and Medical (ISM) bands. The antenna structure consists of a meander-line radiating patch, a flipped-L defected ground plane, and a loading resistor for antenna miniaturization. The MICS/ISM microstrip antenna encapsulated in an oblong-shaped pod was simulated in various lossy-material environments. In addition, the specific absorption rate (SAR) was calculated and compared against the IEEE C95.1 standard. For verification, an antenna prototype was fabricated and experiments carried out in equivalent liquid mixtures, the dielectric constants of which resembled human tissue. The measured impedance bandwidths (|S11| ≤ −10 dB) for the MICS and ISM bands were 398–407 MHz and 2.41–2.48 GHz. The measured antenna gains were −38 dBi and −13 dBi, with a quasi-omnidirectional radiation pattern. The measured SAR was substantially below the maximum safety limits. As a result, the described MICS/ISM microstrip antenna encapsulated in an oblong-shaped pod can be used for real-time gastrointestinal tract diagnosis. The novelty of this work lies in the use of a meander-line microstrip, flipped-L defected ground plane, and loading resistor to miniaturize the antenna and realize the MICS and ISM bands.

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