An insight based on a new theoretical approach has been developed to facilitate the design of a superstrate which plays a key role in realizing a high gain resonance cavity antenna (RCA). The work is aimed to address a profound theoretical basis of controlling the aperture fields by proper shaping of superstrate and to apply it to alleviate the earlier shortcomings along with further improvement in radiation characteristics. This demonstrates an interesting transformation of a metal superstrate from rectangle to an ellipse or an ellipse-circle combination to achieve significant improvements in the aperture fields and hence the sidelobe level (SLL). The antenna characteristics have been verified using simulated data followed by experiments using different sets of prototypes. About 50% reduction in size along with an improvement in the SLL by 5-17 dB compared to its immediate predecessor has been experimentally demonstrated. Proposed theory should find the potential applications in conceiving efficient RCA designs in the future. © 1963-2012 IEEE.

DEBATOSH GUHA

Radio Physics and Electronics

K DUTTA

C KUMAR

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

Theory of Controlled Aperture Field for Advanced Superstrate Design of a Resonance Cavity Antenna With Improved Radiations Properties

IEEE Transactions on Antennas and Propagation

Fabry-Perot Antenna (FPA) is actually a one-dimensional resonant cavity to serve as a high gain radiator. This may consider as a replacement of large antenna array bearing some new features. Higher directivity is obtained through a uniform phase-front developed within the vertical cavity consists of a ground plane and a superstrate layer. The resonance condition of the cavity is maintained by adjusting its dimension as half of the wavelength of the radiating wave. A ‘primary-radiator’ indeed illuminates the Fabry-Perot cavity. Its high-gain characteristics are determined by this primary-radiator along with the superstrate layer. A grounded radiating aperture, a conventional microstrip patch, or a dielectric resonator antenna (DRA) having a broadside radiation pattern commonly serves as the primary-radiator in an FPA design. Traditionally, the superstrates were physically realized as partially reflecting surfaces (PRSs) such as thin dielectric slab, frequency selective surface (FSS), electromagnetic bandgap structure (EBG), artificial magnetic conductor (AMC), metamaterial, metal grid structure, etc. Their gain-enhancement mechanism used to be demonstrated in terms of reflection coefficients [1] or leaky-wave generation. Their basic concept was leakage of electromagnetic energy through the semitransparent superstrate. © 2019 URSI. All rights reserved.

2019 URSI Asia-Pacific Radio Science Conference, AP-RASC 2019

Fabry-Perot resonant cavity antenna: New theory and design opportunity

A Fabry-Perot Cavity Antenna (FPCA) has been proposed to achieve considerably wide bandwidth with high gain. An aperture-fed microstrip-patch has been used as the primary radiator where the excitation has been initiated by a specially designed dual-offset feedline. A metal-grid superstrate has been designed for achieving wide matching bandwidth (50%) with more than 10 dBi gain. It promises up to 16.7 dBi gain with satisfactory performance in terms of side lobe level (-15dB to -21dB) and cross-pol isolation (up to 45dB). © 2018 IEEE.

2018 IEEE Indian Conference on Antennas and Propagation, InCAP 2018

A New Fabry-Perot Cavity Antenna with Wideband Characteristics

A new design of Fabry-Perot cavity antenna (FPCA) has been presented with a unique as well as the most desirable feature of very high-gain maintained over its wide matching bandwidth. About 15.5 dBi average broadside-gain has been achieved over the 19% matching bandwidth. A flat-gain characteristic has been attained using a specially designed conical sidewall. In addition to that, the sidewall will play an important role in reducing the mutual coupling arises due to nearby RF elements. About -16 dB and -19 dB side lobe levels have been obtained satisfactorily in two principle-plane patterns (E- and H-plane) respectively. The cross-polarization purity of the antenna is maintained reasonably below -25 dB over the frequency band. © 2018 IEEE.

Wideband Design of a Fabry-Perot Cavity Antenna with Improved Features

Modification and improvement in the radiation characteristics of a resonance cavity antenna (RCA) have been addressed from a new approach of aperture field synthesis over the superstrate. This concept has been established through a series of systematic studies, which are based on the exciting observations reported very recently by these authors. A process of modification or engineering on the superstrate has been conjectured in view of obtaining reduced sidelobe level (SLL) and/or increased gain. The same has been successfully designed and experimentally demonstrated indicating as much as 10 dB suppression in SLL along with 3 dB improvement in gain compared to its nearest contender. This study promises a potential technique in RCA design along with several attractive features. © 2002-2011 IEEE.

IEEE Antennas and Wireless Propagation Letters

Synthesizing aperture fields over the superstrate of resonance cavity antenna for modifying its radiation properties

A resonance cavity antenna (RCA) has been explored employing nontransparent solid metal sheet as superstrate which, to the best of our knowledge, is reported for the first time. The proposed configuration is much advantageous in terms of design, simplicity, structural stability, fabrication, and cost without compromising in gain, efficiency, and bandwidth. A probe-fed dielectric resonator antenna (DRA) with εr = 10 has been used as the primary radiator. Proposed RCA bearing overall size 1.1λ × 1.1λ × 0.6 λ promises for large impedance bandwidth (~23) with considerably high gain (11.8-12.2 dBi). The superstrate size is relatively compact compared to its semitransparent versions, investigated earlier. Present design has been experimentally validated indicating as much as 12 dBi peak gain with more than 96.5% efficiency. © 1963-2012 IEEE.

Journal	Data powered by TypesetIEEE Transactions on Antennas and Propagation
Publisher	Data powered by TypesetInstitute of Electrical and Electronics Engineers Inc.
ISSN	0018-926X
Open Access	No