UDC 612.396.674.1
INMARSAT-C SYSTEM MARINE EARTH
STATION ANTENNA
V.
V. Golovin, Y. N. Tyschuk, Yu. P. Mickhayluck, I. L. Afonin
Sevastopol
State University, Universitetskaya,
33, Sevastopol 299053, Russia
The paper is received on October
9, 2019
Abstract. This paper presents the results of the development and theoretical
investigation of compact weakly directional antenna of ship earth station system
INMARSAT-C, which differs from the known prototypes by especially qualitative
characteristics of the circular polarization field.
The
antenna design is based on the four-pass spiral structure with quadrature
emitter excitation. Helix emitters are characterized by geometric parameters:
the initial and final winding angle of spirals
βi and
βf, the diameter of the
cylinder d, the number of turns of spirals n. The following values are
experimentally obtained:
βi =13o....
15o; βf =27o....
33o; d=(0.18...0.26)λ0; n=1...2. The excitation mode of
spiral emitters provides the formation of circular polarization, which is
opposite to the winding direction of spiral emitters in the direction of
rotation.
A distinctive feature of the developed antenna is that due to the use of
irregular winding angle radiating helical structures antenna operation mode is
formed, which provides the highest quality polarization characteristics. On the
each of the helical conductors the amplitude-phase current distributions are
formed. They characterized by current antinodes in two regions. While the one
region determines the radiation field with circular polarization in the
direction of the axis Z, the other region determines the radiation field with
circular polarization in the directions close to the plane XY. In this case, the
antenna is characterized by enough uniform radiation in the upper half-space of
the field with polarization as close to circular as possible.
We investigated the radiation characteristics and input characteristics of the
antenna in CAD in the frequency range 1.53 — 1.65 GHz, taking into account the
influence of the dielectric material of the support cylinder and the radioparent
cover. It is shown that in the vertical plane the antenna is characterized by
the radiation pattern of the width 180° at the level of -3 dB and a high
ellipticity coefficient within the entire upper half-space. In this case, the
antenna is characterized by high-quality matching at the inputs of spiral
emitters with VSWR ≤ 1.5.
Key words: helical
antenna, omnidirectional radiation, circular polarization, INMARSAT-C antenna.
References
1.
Electric
& Hybrid Marine Technology International [online].
UKi Media & Events a division of UKIP Media & Events Ltd. Date of access 01.10.2019. Available
at:
https://www.electrichybridmarinetechnology.com/online-magazines.
2.
Vershkov
M.V., Mirotvorsky O.B. Sudovyye antenny [Marine Antennas]. Leningrad.
Sudostroenie Publ. 1990. 304 p. (In Russian)
3.
James
W. Jervis. Integrated antenna system. USA Patent No. 6011524. Application
Date: 24.05.1994. Publication Date: 04.01.2000., H01Q 1/36, H01O 11/08
4.
Bankov
S. E., Davydov A.G. Quadrifilar Antenna. Russian Federation Patent ¹ 2395877.
Application Date: 22.07.2009. Publication Date: 27.07.2010. Bulletin No. 21. (In
Russian)
5.
Michael
J. Josypbiiko. Tapered Direct Fed Quadrifilar Helix Antenna.
USA
Patent No. 6 288 686. Application Date: 23.01.2000. Publication Date: 11.09.2001.
MPK
Í
01 Q 1/36.
6.
Michael
J. Josypenko. Lowangle, Highangle Quadrifilar Helix Antenna. USA Petent No.
6 344 834. Application Date:
20.05.2000. Publication Date: 05.02.2002. MPK Í
01 Q 1/36.
For citation:
V. V. Golovin,
Y. N. Tyschuk, Yu. P. Mickhayluck, I. L. Afonin. INMARSAT-C marine earth station
antenna.
Zhurnal
Radioelektroniki - Journal
of Radio Electronics. 2019. No. 10. Available
at http://jre.cplire.ru/jre/oct19/8/text.pdf
DOI 10.30898/1684-1719.2019.10.8