A new generation ultra-wideband hybrid variant which resembles a 'mushroom' has been explored. The proposed structure shows nearly 137% impedance bandwidth, the largest value that could be achieved so far. A uniform monopole type radiation with 10 dBi peak gain has been examined. © 2014 IEEE.

DEBATOSH GUHA

Radio Physics and Electronics

D GANGULY

S GEORGE

Y M M ANTAR

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Monopole-type dielectric resonator antenna with improved bandwidth characteristics

IEEE Antennas and Propagation Society, AP-S International Symposium (Digest)

This study investigates the effect of loading a monopole-fed cylindrical ring dielectric resonator antenna using a metallic cap and metallic sleeve on its top and outer surface, respectively. The proposed design exhibits a considerable shift of its upper cut-off frequency (from 13.8 to 20.5 GHz for top loading and 8.2 to 15.9 GHz for outer-surface loading) with varying inner radii (height) of the metallic cap (sleeve), thereby providing the bandwidth (BW) controllability. Fabricated prototypes were measured and compared with simulations and good agreement was obtained. The measured return loss exhibits the desired BW control without affecting the peak gain and radiation pattern of the antenna, which is also confirmed by the measured radiation patterns. The proposed concept can be used to reconfigure the BW of the antenna according to the user's requirements and improve signal-to-noise ratio by rejecting unwanted frequency bands without employing any additional filter section. © The Institution of Engineering and Technology.

IET Microwaves, Antennas and Propagation

Bandwidth control of cylindrical ring dielectric resonator antennas using metallic cap and sleeve loading

A new metallic loading on the outer surface of cylindrical ring dielectric resonator antenna is investigated for bandwidth reconfigurability. The proposed design exhibits considerable shift of upper cut-off frequency (from 8.2 - 15.9 GHz) with varying height of the metallic loading on outer surface of the cylindrical ring DR and thereby providing the bandwidth controllability. The designed prototype has been fed by coaxial cable of standard dimensions. This hybrid DRA structure is simulated using CST Microwave Studio Suite 2014. Proposed concept can be used to change the bandwidth requirement without affecting the radiator or its radiation characteristics. © 2015 IEEE.

2015 IEEE Applied Electromagnetics Conference, AEMC 2015

Bandwidth reconfigurable cylindrical dielectric ring resonator antenna with metallic loading

Two geometries of dielectric ring resonator (DRR) have been investigated as new variants for designing ultrawideband hybrid monopole-DRAs (dielectric resonator antennas) with improved features. They are simply hemispherical and conical in shape and have been implemented individually. Hybrid monopole-DRA is actually a combined configuration using a grounded monopole surrounded by a small DRR touching the same ground plane. Compared to an earlier version using cylindrical DRR of same dielectric material, the proposed ones promise for about 25% larger impedance bandwidth maintaining identical gain and radiation properties. As much as 126% impedance bandwidth with consistent monopole type radiation and 2-4 dBi peak gain has been demonstrated using a set of prototypes shaped from dielectric rod with ε r = 10. Physical insight in to the ultrawideband operation along with a comprehensive design guideline is presented. © 2006 IEEE.

IEEE Transactions on Antennas and Propagation

Hybrid monopole-DRAs using hemispherical/conical-shaped dielectric ring resonators: Improved ultrawideband designs

A new pawn-shaped dielectric ring resonator (DRR) fed by a simple quarter-wave monopole has been investigated as a new variant of the hybrid monopole-dielectric resonator antenna (DRA). The new geometry, conceived intuitively, significantly improves the impedance bandwidth compared to all earlier versions reported in open literature. S11 &lt; - 10 dB occurring over 5.5-23 GHz has been experimentally demonstrated, indicating over 4:1 ratio bandwidth, i.e., more than 122% impedance bandwidth around the center of the band. The prototype has been shaped from a dielectric rod with εr = 10. Such ultrawideband (UWB) response is caused by multiple resonances occurring by the hybrid monopole-DRA structure. These resonances are identified through several experimental and simulation studies. Uniform monopole-type radiation occurring over the entire bandwidth has been confirmed using measured and simulated results. The peak gain varies from 4 to 6 dBi as a function of frequency. Such useful properties can be successfully used to realize UWB monopole antennas for wireless communications and as wideband electromagnetic interference (EMI) sensors. © 2009 IEEE.

IEEE Antennas and Wireless Propagation Letters

New pawn-shaped dielectric ring resonator loaded hybrid monopole antenna for improved ultrawide bandwidth

This letter examines in detail multiple resonance phenomenon responsible for the ultra wideband response of the hybrid monopole-dielectric resonator antenna (DRA). The physical insight gained by this investigation has lead to improved guidelines for designing the antennas for any specified frequency band. These simple guidelines are then verified using both simulated and measured data. © 2006 IEEE.

Improved design guidelines for the ultra wideband monopole-dielectric resonator antenna

A new half-hemispherical dielectric resonator antenna (h-HDRA) is proposed and a two-element h-HDRA configuration is employed to design a broadband monopole-type radiator. Two half sections of a hemispherical DRA are employed to enhance the impedance bandwidth by introducing an additional resonant mode. Since the new geometry of an h-HDRA is studied here for the first time, it is characterized using simulation and experimental studies. Two closely spaced resonant modes, which in a two-element h-HDRA generate monopole-type radiation are investigated. Results for both the single and two-element h-HDRAs are presented. As much as 35% impedance bandwidth (S11 &lt; -10 dB) with more than S dBi peak gain, 99.08% efficiency and monopole-type radiation pattern has been demonstrated using a prototype occupying a compact volume measuring 0.48λ0 by 0.2λ0 approximately, λ0 being the wave length corresponding to the center of the impedance bandwidth. © 2006 IEEE.

Journal	Data powered by TypesetIEEE Antennas and Propagation Society, AP-S International Symposium (Digest)
Publisher	Data powered by TypesetInstitute of Electrical and Electronics Engineers Inc.
ISSN	1522-3965
Open Access	No