A new method of suppressing cross-polarized (XP) radiation using resonant-type defected ground structure (R-DGS) on microstrip antenna has been proposed in this communication. A linearly shaped full wavelength R-DGS has been proposed and experimentally verified for different microstrip geometries. The design is supported by thorough investigations on the physical interaction between R-DGS and XP generating fields. Unlike previously explored nonresonant-type defects, this new approach is independent of patch geometry. A consistent suppression of the H-plane XP fields well below $- 30\,\hbox{dB}$ for different patch geometries has been experimentally demonstrated. © 1963-2012 IEEE.

DEBATOSH GUHA

Radio Physics and Electronics

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

Reduction in Cross-Polarized Radiation of Microstrip Patches Using Geometry-Independent Resonant-Type Defected Ground Structure (DGS)

IEEE Transactions on Antennas and Propagation

This communication proposes a new idea of compensating spurious radiations usually occurring from the sharp transitions at patch to feed and feed to impedance transformer junctions which result in added cross-polarized (XP) fields in planar microstrip-fed patches. A strategic design and deployment of defected ground structure (DGS) have been explored successfully as a potential means to resolve such long-standing radiation issues. The quantum of radiations from the feed has been theoretically estimated. These along with the main source of XP fields (higher order mode) have been addressed by introducing a composite type of DGS. The experimental validation executed at the C-band establishes this simple low-cost solution with a promise of 10 to 14 dB improvement in the H-plane XP fields. It is also ensured that the proposed technique is equally useful in realizing dual-fed dual-polarized configurations without affecting the primary radiation and antenna performance. © 1963-2012 IEEE.

Simultaneous Compensation of Microstrip Feed and Patch by Defected Ground Structure for Reduced Cross-Polarized Radiation

Defected ground structure (DGS) integrated microstrip array has been explored and demonstrated here for the first time with the primary aim of achieving improved polarization purity. A shaped DGS with variable configuration has been conceived and designed for rectangular arrays. This unleashes new potential of DGS design by reducing the etched out area by 50%. A 2 × 2 DGS integrated array has been designed and experimentally demonstrated in X-band showing 12 dB improvement in the isolation between the copol and cross-pol radiations. © 2002-2011 IEEE.

IEEE Antennas and Wireless Propagation Letters

Defected ground structure integrated microstrip array antenna for improved radiation properties

Defected ground structure (DGS)-integrated rectangular microstrip patch has been experimentally investigated with an aim to improve polarisation purity in radiated fields. Width to length ratio (aspect ratio) of a patch attributes different characteristic features. Therefore present experimental studies have been executed for four different aspect ratio values like 1.6, 1.3, 1.0 and 0.8. Folded defects have been employed in H-plane. Possibility of achieving high polarisation purity (over 25 dB isolation between co- to cross-polarised fields) with improved impedance bandwidth has been demonstrated. The variation in XP fields as a function of the patch aspect ratio has been investigated and a strong physical insight into the modal fields with and without DGS has been developed. © The Institution of Engineering and Technology 2014.

IET Microwaves, Antennas and Propagation

Defected ground structure (DGS)-integrated rectangular microstrip patch for improved polarisation purity with wide impedance bandwidth

Elliptical microstrip patch, etched on a grounded PTFE substrate, has been examined here for the first time as a linearly polarized (LP) antenna. All earlier investigations dealt with only circularly polarized design. Inherent shortcoming of poor polarization purity has been alleviated using the newly developed approach of using defected ground structure. Apart from a design guideline, a comprehensive study using a set of prototypes with different eccentricity values has been provided. Possibility of using elliptical patch as a new LP radiating element with improved features relative to an identical circular microstrip has been documented for the first time. © 2012 Wiley Periodicals, Inc.

Microwave and Optical Technology Letters

Linearly polarized elliptical microstrip antenna with improved polarization purity and bandwidth characteristics

Experiments with probe-fed circular patches using conventional and defected ground planes flashed some interesting features relating to cross-polarized (XP) electric fields and associated radiations before the present authors. Those led to a series of new investigations for understanding the nature of XP fields and to deal with them using defected ground structure (DGS) for improved XP performance. In the first phase of investigation, the XP radiations of a probe-fed circular patch with conventional ground plane have been critically studied as a function of the radial probe location. Remarkably significant effect is experimentally demonstrated. New information about orthogonal resonant fields and its importance in designing an antenna is provided. In the second phase of investigation, limitations of dot-shaped DGS in reducing XP level are experimentally studied. As its improved variants, two new DGS geometries such as annular ring and circular arcs have been explored. The arc-DGS appears to be highly efficient in terms of suppressing XP fields. Suppression by 10-12 dB has been experimentally demonstrated. Each design has been experimented in both C- and X-bands to earn confidence on the measured data. © 2006 IEEE.

Nature of cross-polarized radiations from probe-fed circular microstrip antennas and their suppression using different geometries of defected ground structure (DGS)

Microstrip and Printed Antennas: New Trends, Techniques and Applications

Preface

The input impedance of a rectangular microstrip patch with a variable air gap has been studied theoretically and experimentally. Unlike earlier investigations, the influence of the air gap along with the varying patch width in changing the patch impedance is thoroughly examined. An efficient computer aided design formulation is developed and used for this study, and the computed results are experimentally verified. Superiority of the present theory compared to some earlier models is also indicated. © The Institution of Engineering and Technology 2009.

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