Article
Airport Spatial Usability in Measuring the Spherical Antenna
Properties on Small Aircraft
Ján Labun
1
, Pavol Kurdel
2,
* , Marek
ˇ
Ceškoviˇc
2
, Alexey Nekrasov
3,4
, Mária Gamcová
1
and Natália Gecejová
2
Citation: Labun, J.; Kurdel, P.;
ˇ
Ceškoviˇc, M.; Nekrasov, A.; Gamcová,
M.; Gecejová, N. Airport Spatial
Usability in Measuring the Spherical
Antenna Properties on Small Aircraft.
Sensors 2021, 21, 7920. https://
doi.org/10.3390/s21237920
Academic Editor: Ángela
María Coves Soler
Received: 4 November 2021
Accepted: 24 November 2021
Published: 27 November 2021
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1
Faculty of Electrical Engineering and Informatics, Technical University of Košice, Letná 9,
04200 Košice, Slovakia; jan.labun@tuke.sk (J.L.); maria.gamcova@tuke.sk (M.G.)
2
Faculty of Aeronautics, Technical University of Košice, Rampová 7, 04121 Košice, Slovakia;
marek.ceskovic@tuke.sk (M.
ˇ
C.); natalia.gecejova@tuke.sk (N.G.)
3
Institute for Computer Technologies and Information Security, Southern Federal University, Chekhova 2,
347922 Taganrog, Russia; alexei-nekrassov@mail.ru
4
Department of Radio Engineering Systems, Saint Petersburg Electrotechnical University, Professora Popova 5,
197376 Saint Petersburg, Russia
* Correspondence: pavol.kurdel@tuke.sk; Tel.: +421-903-626-637
Abstract:
The strict safety requirements of air transport for nonstandard placement of electronic
onboard systems require an innovative approach to the experimental verification of the placement
of these devices. Particular attention is required to the location of these electronic devices’ antenna
systems on the fuselage. A prerequisite for determining the location of the antenna and verifying its
radiation is a thorough knowledge of the radio communication transmission of onboard electronic
systems in cooperation with terrestrial or satellite systems. From this point of view, this article
focuses on an innovative method of verifying the spherical radiation characteristics of the antenna
of an onboard rescue system emergency locator transmitter (ELT) to assess its communication link
with the Cospas-Sarsat satellite system. The measurement is performed on a small sports two-seater
aircraft with an antenna placed in an unusual place in the aircraft’s cabin, between the seats. It was
impossible to use a suitable nonreflective attenuation chamber for the measurement, so we present a
method and procedure for this type of measurement in the open space of an airport. The achieved
results prove the plausibility and reproducibility of the measurement. Furthermore, combining
several polar radiation characteristics makes it possible to obtain an idea, even if only a part, of the
spatial (spherical) radiation characteristic. This article presents a simple method of measuring the
characteristics of aircraft antennas when it is not possible to use a suitable professional nonreflective
attenuation chamber for measurements for various reasons. This method can also be used on other
larger means of transport or other objects that experience the same problem.
Keywords:
emergency locator transmitter system; flight safety; small aircraft; spherical antenna
characteristics
1. Introduction
Air traffic in today’s modern Europe is primarily focused on flights by ultralight
and light aircraft. Dangerous situations are common for this type of air traffic. Due to
these situations, the implementation of a collision-avoidance system and a rescue system
is desirable, even required. The affordability of this type of aircraft has caused their
quantitative increase as a proportion of air traffic, also supported by the increase in flight
hours, especially for their use in sports or private passenger transport. The tendency in the
future will be to automate the control of this type of aircraft. So, this type of transport will
expand even further. For this reason, even stricter requirements will be placed on air safety
control [1,2].
In the case of an emergency, all available systems are used to save the life of the pilot
and crew [
1
–
4
]. These can be activated in different phases of flight: automatically in the
Sensors 2021, 21, 7920. https://doi.org/10.3390/s21237920 https://www.mdpi.com/journal/sensors
