COMPACT ULTRA-WIDEBAND CARDIOID VIVALDI RADIATOR WITH RECTANGULAR IMPEDANCE INSERTS
Abstract
The paper presents the design of the cardioid-shaped Vivaldi radiator with rectangular impedance
inserts along the edges of its metallization. The influence of impedance inserts, their location, and parameters
on the characteristics of the radiator is investigated. The frequency characteristics of the voltage
standing wave ratio (VSWR), realized gain, efficiency, and cross-polarization level of the radiator without
and with impedance inserts are given. The developed radiator is electrically compact (electrical height at
the upper operating frequency is equal to 0.740 λ, and at the lower operating frequency is equal to
0.127 λ) and ultra-wideband with an overlap ratio (OR) of 5.809:1 in the operating frequency band
127.3–739.5 MHz. The width of the impedance inserts varied from 5.0 mm to 25.5 mm towards the tapered
slot. At the same time, an increase width leads to a slight expansion of the operating frequency band and
an increase of OR. But the realized gain practically does not change since the radiator is weakly directional
and its realized gain depends mainly on the size of the aperture. The numerical values of efficiency
and cross-polarization characteristics also remained virtually unchanged with increasing insert width.
The optimal width of the impedance inserts is equal to 25.5 mm. The height of the impedance inserts was
measured from the top of the radiator. The influence of impedance inserts with a height of 60, 100, 140,
145, and 160 mm is considered. It has been determined that as their height increases, the width of the
operating band increases, but the average VSWR level in the frequency band 180–280 MHz gradually
increases. The realized gain, efficiency, and cross-polarization level also remain virtually unchanged with
the increasing height of the inserts. The optimal height of the impedance inserts is equal to 25.5 mm. Thus,
the introduction of impedance inserts makes it possible to expand the operating frequency band of the
radiator.
References
Tekhnosfera, 2012, 560 p.
2. Lazorenko O.F., Chernogor L.F. Sverkhshirokopolosnye signaly i fizicheskie protsessy [Ultrawideband
signals and physical processes], Radiofizika i radioastronomiya [Radio physics and radio astronomy],
2008, No. 2, pp. 166-194.
3. Chubinskiy N.P., Kir'yashkin V.V., Khi N.K. Ob ispol'zovanii sverkhshirokopolosnykh signalov dlya
identifikatsii radiolokatsionnykh ob"ektov [On the use of ultra-wideband signals to identify radar objects]],
Zhurnal Radioelektroniki [Journal of Radioelectronics], 2010, No. 5, pp. 1-13.
4. Latha T., Ram G., Kumar G. A., Chakravarthy M. Review on Ultra-Wideband Phased Array Antennas,
IEEE Access, 2021, Vol. 9, pp. 129742-129755.
5. Gibson P.J. The Vivaldi aerial, Proc. 9th European Microwave Conference, 1979, pp. 101-105.
6. Dixit A.S., Kumar S. A Survey of Performance Enhancement Techniques of Antipodal Vivaldi Antenna,
IEEE Access, 2020, Vol. 8, pp. 45774-45796.
7. Gevorkyan A.V., Yukhanov Y.V., Privalova T.Y. The radiation characteristics of the Vivaldi antenna
located on a cylindrical surface, 2017 Progress in Electromagnetics Research Symposium - Fall
(PIERS - FALL), 2017, pp. 1780-1784.
8. Gevorkyan A.V., Yukhanov Y.V., Privalova T.Y. The Radiation Characteristics of the Four-Element
Vivaldi Antenna Arrays, Which Located on the Cylindrical Surface, 2018 Progress in Electromagnetics
Research Symposium (PIERS-Toyama), 2018, pp. 1617-1620.
9. Kosak R.E., Gevorkyan A.V. UWB Cardioid-Shaped Vivaldi Antenna, 2023 Radiation and Scattering
of Electromagnetic Waves (RSEMW), 2023, pp. 228-231.
10. Kosak R.E., Gevorkyan A.V. Research of Ways to Improve Radiation Characteristics of Phased Array
Radiator Based on Vivaldi Antenna, 2021 Radiation and Scattering of Electromagnetic Waves
(RSEMW), 2021, pp. 211-214.
11. Kosak R.E., Gevorkyan A.V., Yukhanov Yu.V. Izluchatel' fazirovannoy antennoy reshetki
uzkougol'nogo skanirovaniya [Narrow-angle scanning phased array antenna radiator], Komp'yuternye i
informatsionnye tekhnologii v nauke, inzhenerii i upravlenii (KomTekh-2022) [Computer and information
technologies in science, engineering and management (KomTech-2022)], 2022, pp. 258-263.
12. Voskresenskiy D.I., Gostyukhin V.L., Maksimov V.M., Ponomarev L.I. Ustroystva SVCh i antenny
[Microwave devices and antennas]. 2nd ed. Moscow: Radiotekhnika, 2006, 376 p.
13. Gevorkyan A.V. Sverkhshirokopolosnaya antenna Vival'di s malym koeffitsientom stoyachey volny [Ultra-
wideband Vivaldi antenna with low standing wave ratio], Aktual'nye problemy radiofiziki: Sb. trudov
VII Mezhdunarodnoy nauchno-prakticheskoy konferentsii [Current problems of radiophysics: Collection
of proceedings of the VII International Scientific and Practical Conference], 2017, pp. 34-37.
14. Sahar Saleh, Mohd Haizal Jamaluddin, Faroq Razzaz, Saud M. Saeed, Nick Timmons, Jim Morrison
Compactness and performance enhancement techniques of ultra-wideband tapered slot antenna:
A comprehensive review, Alexandria Engineering Journal, 2023, Vol. 74, pp. 195-229.
15. Shi X., Cao Y., Hu Y., Luo X., Yang H.and Ye L.H. A High-Gain Antipodal Vivaldi Antenna With Director
and Metamaterial at 1–28 GHz, IEEE Antennas and Wireless Propagation Letters, 2021,
Vol. 20, No. 12, pp. 2432-2436.
16. Zhu S., Liu H. and Wen P. A New Method for Achieving Miniaturization and Gain Enhancement of
Vivaldi Antenna Array Based on Anisotropic Metasurface, IEEE Transactions on Antennas and Propagation,
2019, Vol. 67, No. 3, pp. 1952-1956.
17. Zhou B. and Cui T.J. Directivity Enhancement to Vivaldi Antennas Using Compactly Anisotropic Zero-
Index Metamaterials, IEEE Antennas and Wireless Propagation Letters, 2011, Vol. 10, pp. 326-329.
18. Khamed E.A. Makh'yub, Kisel' N.N. Otsenka effektivnosti primeneniya metamateriala v razrabotkakh
mikropoloskovykh antenn na osnove LTCC-tekhnologii [Evaluation of the metamaterial application
efficiency in the development of microstrip antennas based on LTCC technology], Izvestiya YuFU.
Tekhnicheskie nauki [Izvestiya SFedU. Engineering Sciences], 2019, No. 3 (17), pp. 179-190.
19. Bankov S.E., Kurushin A.A. Proektirovanie SVCh ustroystv i antenn s Ansoft HFSS [Designing microwave
devices and antennas with Ansoft HFSS], Zhurnal Radioelektroniki [Journal of Radio Electronics],
2009, No. 5, 736 p.
20. High Frequency Structural Simulator (HFSS), ANSYS. Available at: URL: www.ansys.com (accessed
12 March 2024).
