Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
Search Results
Item A High-Gain Circularly Polarized Antenna Using Zero-Index Metamaterial(Institute of Electrical and Electronics Engineers Inc., 2019) Tharehalli Rajanna, P.K.T.; Rudramuni, K.; Kandasamy, K.In this letter, a novel high-gain circularly polarized (CP) antenna based on the zero-index metamaterial (ZIM) is presented. A square ring with two asymmetrical splits is used as a unit cell to achieve high gain and circular polarization. The 9 × 9 periodic array unit cells act as an aperture efficient focusing metasurface lens and polarization converter for a primary source antenna. The focusing effect of the ZIM enhances the gain of the microstrip patch antenna placed above it by an amount of 5-6 dB. Also, the ZIM converts the linearly polarized wave emitted by the patch antenna into circularly polarized waves. The circular polarization is achieved by optimizing the two split gaps on the ring of the unit cell, which gives two orthogonal polarizations with the required phase. The proposed design is fabricated and verified experimentally. The prototype has measured impedance bandwidth from 7.04 to 7.68 GHz. The 3 dB axial ratio is achieved from 7.11 to 7.56 GHz, with a peak gain of 12.31 dBic at 7.45 GHz. The gain of around 11.5 dBic is achieved over the entire CP bandwidth with a good cross-polarization level. © 2002-2011 IEEE.Item Compact triband circularly polarized planar slot antenna loaded with split ring resonators(John Wiley and Sons Inc. P.O.Box 18667 Newark NJ 07191-8667, 2019) Tharehalli Rajanna, P.K.T.; Rudramuni, K.; Kandasamy, K.In this article, a coplanar waveguide (CPW) fed triband circularly polarized (CP) planar slot antenna loaded with split ring resonators (SRRs) is presented. The truncated slot antenna resonates at 4.15 GHz, which gives two orthogonal degenerate modes to produce circular polarization at the first band. The second and third band resonances are achieved at 4.77 GHz and 5.1 GHz respectively due to the loading of SRRs on the slot antenna. The electric fields produced by the single and multiple split gaps in each ring of SRR1 and SRR2 produce CP at the second and third band. All three bands are tuned independently to achieve optimized axial ratio bandwidth. The antenna is fabricated and verified experimentally. The measured results give impedance bandwidth of 64.54% and axial ratio bandwidths of 11.76%, 1.9%, and 3.87% at first, second, and third band, respectively. © 2019 Wiley Periodicals, Inc.Item Goubau line based end-fire antenna(John Wiley and Sons Inc. P.O.Box 18667 Newark NJ 07191-8667, 2019) Rudramuni, K.; Tharehalli Rajanna, P.K.T.; Kandaswamy, K.; Majumder, B.; Zhang, Q.This article proposes a simple and low profile planar Goubau line based end-fire antenna. End-fire radiation is achieved by modifying the Goubau line into inverted periodic arrangement of V-shaped unit cells. Designed prototype is simulated and verified experimentally. Both the simulated and measured results are in good agreement. Proposed antenna radiates toward end-fire direction between 7.8 and 8.3 GHz. The maximum gain of the antenna is obtained around 7.2 dBi. The average efficiency is observed 70% over the entire operating bandwidth. Proposed end-fire antenna has a single metallic layer with simple configuration which is easy to fabricate and also easy to integrate with other electronics circuits. The proposed antenna can be used for satellite and RADAR applications. © 2019 Wiley Periodicals, Inc.