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Abstract

A wideband antenna with dual band characteristic at 5.33/14.3GHz with resonating frequencies for wireless applications is presented. The strategy of the design is to introduce multiband in antenna band. Bandwidth of the antenna increases by embedding annular ring on the radiating patch and four bands are achieved by introducing coupling gap between the patches. Surface current distribution is analyzed at different resonating frequencies for understanding the radiation mechanism and effect of annular ring. The antenna parameters such as return loss, radiation pattern, gain, VSWR and group delay are discussed. The impedance bandwidth of the proposed dual band antenna at lower resonant frequency is 12.7% (simulated) and 9.8 % (measured) whereas at upper resonant frequency is 15.3 % (simulated) and 13.97 % (measured).

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Authors and Affiliations

Karunesh Srivastava
Sweta Singh
Aditya Kumar Singh
Rajeev Singh
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Abstract

A compact planar multiband antenna operating at 3.1 (S-band) /4.7/6.4/7.6 (C-band) /8.9/10.4/11.8 GHz (X-band) is presented. The proposed Microstrip Patch Antenna (MSPA) consists of a rectangular radiator in which an E-shaped slot is etched out and a microstrip feed line. The E-shaped slot modifies the total current path thereby making the antenna to operate at seven useful bands. No external impedance matching circuit is used and the impedance matching at these bands are solely achieved by using a rectangular microstrip feed line of length 10mm (L6) and width 2mm (W10). The antenna has a compact dimension of ���� × ���� × ��. �� ������ and exhibits S11<-10dB bandwidth of about 6.45% (3.2-3.0GHz), 8.5% (4.9-4.5GHz), 7.6% (6.7-6.2GHz), 3.9% (7.8-7.5GHz), 5.7% (9.1-8.6GHz), 1.2% (10.44-10.35GHz) and 2.2% (11.87-11.62GHz). The simulation analysis of the antenna is carried out by using HFSS v.13.0.

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Authors and Affiliations

Imran Khan
Geetha D. Devanagavi
K.R. Sudhindra
Tanweer Ali
R.K. Rashmitha
Raksha Gunjal
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Abstract

In the predominantly polyploid and apomictic genus Hieracium (Asteraceae) sexual diploids are extremely rare and their distribution is limited mainly to the refugial areas of southern Europe. Here we characterized for the first time the chromosome complex of the relict species Hieracium bracteolatum from a diploid population on the Greek Island of Evia. The cytogenetic analysis based on classical chromosome staining, C-banding/DAPI method and fluorescence in situ hybridization with rDNA probes (rDNA-FISH) showed no major differences in the karyotype structure between this relict species and other diploids within the genus, especially in terms of chromosome morphology and rDNA location. Our study is part of the still very scarce research on the karyotype organization in sexual Hieracium taxa.
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Bibliography

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Authors and Affiliations

Aleksandra Grabowska-Joachimiak
1
ORCID: ORCID
Magdalena Żytkowicz
1
Dagmara Kwolek
2
ORCID: ORCID
Zbigniew Szeląg
3
ORCID: ORCID

  1. Department of Plant Breeding, Physiology and Seed Science, Faculty of Agriculture and Economics, University of Agriculture in Krakow, Łobzowska 24, 31-140 Kraków, Poland
  2. Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland
  3. Pedagogical University of Cracow, Institute of Biology, Podchorążych 2, 30-084 Kraków, Poland

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