Electrically switchable, Ka-band slotted waveguide antenna array system
An original electrically switchable, Ka-band slotted waveguide antenna array system has been recently developed, produced, and tested. The system consists of four identical sections, which are connected to a radar transmitter/receiver by means of a high-power, multipole p-i-n switch. The introduce...
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Electrically switchable, ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ.
2008
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| Cite this: | Electrically switchable, Ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1859606298717323264 |
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| author | Sekretarov, S.S. Vavriv, D.M. Volkov, V.A. Natarov, M.P. Glamazdin, V.V. |
| author_facet | Sekretarov, S.S. Vavriv, D.M. Volkov, V.A. Natarov, M.P. Glamazdin, V.V. |
| citation_txt | Electrically switchable, Ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ. |
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| description | An original electrically switchable, Ka-band slotted waveguide antenna array system has been recently developed, produced, and
tested. The system consists of four identical sections, which are connected to a radar transmitter/receiver by means of a high-power,
multipole p-i-n switch. The introduced p-i-n switch enables for a fast electrical scanning of the antenna beam what essentially extends
possible areas of the antenna system application. The antenna system is used in a helicopter collision avoidance, surveillance, and weather
radar. This paper describes design features of the antenna system, its main characteristics, results of its testing, and the antenna integration in
the radar.
У роботі представлено оригінальну конструкцію хвилевідно-щілинної антенної системи Ka-діапазону з електричним скануванням променя. Система складається з чотирьох однакових секцій, які підключені до приймача-передавача через мультипольний p-i-n перемикач великої потужності. Запропонований p-i-n перемикач дозволяє здійснювати швидке електричне сканування променя антени, що істотно збільшує сферу застосування антенної системи. Розроблену антенну систему було застосовано в радарі, призначеному для забезпечення безпеки польоту гелікоптерів, а також контролю метеоумов. У статті описано властивості антенної системи, наведено її основні характеристики, результати тестувань та інтеграції антени в радар.
В работе представлена оригинальная конструкция волноводно-щелевой антенной системы Ka-диапазона с электрическим сканированием луча. Система состоит из четырех одинаковых секций, которые подключены к приемо-передатчику через мультипольный p-i-n переключатель большой мощности. Предложенный p-i-n переключатель позволяет осуществлять быстрое электрическое сканирование луча антенны, что существенно расширяет область применения антенной системы. Разработанная антенная система была применена в радаре, предназначенном для обеспечения безопасности полета вертолетов, а также контроля метеоусловий. В статье описаны свойства антенной системы, приведены ее основные характеристики, результаты тестирования и интеграции антенны в радар.
|
| first_indexed | 2025-11-28T03:30:23Z |
| format | Article |
| fulltext |
__________
ISSN 1028-821X Радиофизика и электроника, том 13, № 3, 2008, с. 489-493 ИРЭ НАН Украины, 2008
УДК 537.86:621.396.677.71
ELECTRICALLY SWITCHABLE, KA-BAND SLOTTED WAVEGUIDE ANTENNA ARRAY SYSTEM
S. S. Sekretarov, D. M. Vavriv, V. A. Volkov, M. P. Natarov
*
, V. V. Glamazdin
*
Institute of Radio Astronomy of the National Academy of Science of Ukraine
4, Chervonopraporna St., Kharkov, 61002, Ukraine
E-mail: vavriv@radar.kharkov.com
* A. Usikov Institute of Radio Physics and Electronics of the National Academy of Science of Ukraine
12, Ac. Proskura St., Kharkov, 61085, Ukraine
E-mail: natarov@ire.kharkov.ua
An original electrically switchable, Ka-band slotted waveguide antenna array system has been recently developed, produced, and
tested. The system consists of four identical sections, which are connected to a radar transmitter/receiver by means of a high-power,
multipole p-i-n switch. The introduced p-i-n switch enables for a fast electrical scanning of the antenna beam what essentially extends
possible areas of the antenna system application. The antenna system is used in a helicopter collision avoidance, surveillance, and weather
radar. This paper describes design features of the antenna system, its main characteristics, results of its testing, and the antenna integration in
the radar. Figs. 9. Tabl. 1. Ref.: 4 titles.
Key words: slotted waveguide antenna, Ka-band antenna, p-i-n switch, collision avoidance radar.
In this paper, we describe an electrically
switchable, Ka-band antenna array system, which has
been designed for airborne radar applications. The
system consists of four identical sections, which are
slotted waveguide arrays. The sections are connected
to a radar transmitter/receiver by means of a high-
power, multipole p-i-n switch. The slotted waveguide
arrays have been developed by using modern antenna
simulation techniques and original approaches to the
antenna design described in [1, 2]. The p-i-n switch
used in the antenna system is the state-of-the-art
device which is characterized by both a high
commutated power – of about several kilowatts, and
a rather low switching time – of about several
microseconds.
The developed antenna system combines
known advantages of slotted waveguide arrays, like
high efficient, strength of the antenna construction,
extended frequency operation range, high power
operation capability, small dimensions and weight.
The introduced p-i-n switch enables for a fast
electrical scanning of the antenna beam what
essentially extents possible areas of the antenna
system application. So far, the antenna system has
been successfully introduced in a helicopter collision
avoidance, surveillance, and weather radar. The radar
is intended for providing the flight safety of
helicopters, including detection of wires of power
lines and other obstacles, monitoring of
meteorological conditions on the direction of flight,
and providing a secure landing.
1. Design of the antenna section. Each
individual section of the antenna system is produced
as a slotted antenna array made of rectangular
waveguides, as shown in Fig. 1. The section consists
of a collection of nine identical linear radiating
arrays. Longitudinal slots are arranged in the broad
wall of the radiating waveguides. The radiating
waveguides are fed via inclined coupling slots from a
crossed feeding waveguide. In order to realize a
wideband antenna operation, the arrays operate in a
non-resonant (travelling-wave) radiating mode. The
feeding waveguide is a resonant (standing-wave)
device.
Fig. 1. Antenna construction
The H-plane radiation pattern is determined
by that of the single radiating waveguide, whereas the
E-plane pattern is defined by feeding of the radiating
waveguides. According to the work [1], we synthesize
the radiation pattern in both planes by using the
following amplitude distribution:
,
1
exp
1
1
2
2
N
Nn
N
Nn
U n
(1)
where Un is the normalized amplitude at the n-th slot;
12N is the number of slots, = 0,8, = 2,3,
= 0,85. This distribution enables for the realization
x
z
y
mailto:vavriv@radar.kharkov.com
mailto:natarov@ire.kharkov.ua
С. С. Секретарев и др. / Волноводно-щелевая антенна…
__________________________________________________________________________________________________________________
490
of radiation patterns having both maximal gain and
minimal sidelobe level.
As an initial approximation, we synthesize
the radiating array by using the energy method [3].
The dependence of the slot radiation coefficient
)( 1x versus the slot offset from the waveguide
centerline has been determined by using FDTD-
simulations. So the slot offsets have been determined
from the function )( 1x , which is shown in Fig. 2. It
should be mentioned that the slot dimensions, used in
our computations, were as follows: the length of
3.9 mm and the width of 0,8 mm. Such length is
close to the slot resonant length at the frequency of
35.5 GHz.
Fig. 2. Slot radiation coefficient versus the slot offset
The final values for the slot offsets have
been obtained by using the FDTD-simulations. The
performed synthesis has resulted in optimal slot
offsets, which realize the needed amplitude
distribution. The initial and optimal slot offsets are
shown in Fig. 3. The difference between them shows
the effect of mutual coupling of the radiating slots.
Fig. 3. First approximation for the slot offsets and that after the
adjustment: – energy method; – after adjustment
Neighboring slots are spaced at a distance of
about 2/g , and so they have to be shifted at the
opposite sides from the waveguide centerline to
produce an additional phase shift of for the
required phase distribution.
The usage of the standard Ka-band
waveguide in the antenna design is not acceptable
because the E-plane slot spacing in this case is about
the wavelength, and due to this, intensive grating
lobes are excited. In order to overcome the problem,
we have designed the plane array consisted of
9 linear slotted waveguides with the crossection of
5,5 mm over 2,5 mm and the wall thickness of
0,9 mm.
The energy distribution between the
radiating waveguides is arranged by means of a
crossed waveguide with inclined slots in the center of
its broad wall. Such feeding is sufficiently compact,
easy-to-design, and easy-to-make. The radiating
waveguides are fed in-phase what is achieved by the
half-of-wavelength slot spacing in the feeding
waveguide along with the opposite in sign tilt of the
neighboring slots. Such slot spacing is realized
provided the feeding waveguide width is
2
00 2/12/ taa rf ,
where t is the wall thickness between the radiating
waveguides; fa and ra are the broad wall widths
for the feeding and radiating waveguides,
respectively. In accordance with this formula, the
fa -value is 5,77 mm.
The slot dimensions for the feeding
waveguide have been selected as 4 mm over 0,8 mm.
Again, FDTD-simulations have been used to
calculate the coupling coefficient for the crossed
waveguides. In Fig. 4, the coupling coefficient
amplitude (a) and the phase (b) are shown as
functions of the slot tilt angle measured with respect
to the feeding waveguide axis.
The needed tilt angle for each of the
coupling slots has been determined from Fig. 4 with
the following adjustment by using of FDTD-
simulations to realize the aperture distribution (1) in
the x-direction.
As the final step of the antenna design, we
have performed numerical simulations of the
complete antenna structure, which include the plane
array and the feeding system. These simulations have
confirmed the correctness of the solution introduced.
The beam width realized by the antenna
section is 10 in the E-plane and 2 in the H-plane.
The section dimensions are 310×72×9 mm
3
.
Slot offset x1, mm
S
lo
t
ra
d
ia
ti
o
n
c
o
ef
fi
ci
en
t
α
(x
1
)
Slot number
S
lo
t
o
ff
se
t
x 1
,
m
m
С. С. Секретарев и др. / Волноводно-щелевая антенна…
__________________________________________________________________________________________________________________
491
a)
b)
Fig. 4. Cross-waveguides coupling coefficient versus the slot tilt
angle: a) amplitude; b) phase
2. Measurement results. The designed
antenna sections have been fabricated by using metal
coating, milling, electric-sparking, and laser welding
technologies. These technologies allow for producing
such antennas with rather high reproducibility of the
antenna characteristics. We have also observed a
rather high degree of compliance of the measured and
simulated results. In Fig. 5, the corresponding
comparison is shown for the radiation patterns in both
planes.
Fig. 6 plots and compares the dependence of
the VSWR on the operating frequency obtained from
the theoretical and experimental results. The antenna
demonstrates a rather low value of the VSWR in the
prescribed frequency band what simplifies its
matching with radar transmitter and receiver.
In order to protect the antenna from dust and
moisture, a radome coating has been designed and
introduced. The radome is made of a 4 mm foam sheet
placed directly on the antenna radiating surface. The
sheet is stabilized by means of 50 µm lavsan film. As
it can be seen from Fig. 5, the radome exerts a rather
small influence on the radiation pattern.
The main lobe of the pattern measured in the
H-plane is a little wider (below the 3 dB level) than
the calculated one. It is because of phase errors
associated with the finite tolerance of the antenna
fabrication. The level of sidelobes is as low as
–23 dB what satisfy the design goal as well.
a)
b)
Fig. 5. Calculated and measured radiation pattern for designed
plane slotted array: a) – H-plane; b) – E-plane. – calculated;
– – measured; – measured with cover
Fig. 6. – calculated and – measured VSWR
3. Antenna system. The complete antenna
system consists of four independent slotted waveguide
sections, which are shown in Fig. 7 integrated to a
transmitter/receiver module of an airborne radar.
Coupling slot titl angle, degress
C
ro
ss
-w
av
eg
u
id
es
c
o
u
p
li
n
g
co
ef
fi
ci
en
t
am
p
li
tu
d
e
Coupling slot titl angle, degress
C
ro
ss
-w
av
eg
u
id
es
c
o
u
p
li
n
g
co
ef
fi
ci
en
t
p
h
as
e
θ, degress
H
-p
la
n
e
ra
d
ia
ti
o
n
p
at
te
rn
,
d
B
E
-p
la
n
e
ra
d
ia
ti
o
n
p
at
te
rn
,
d
B
θ, degress
Frequency, GHz
V
S
W
R
С. С. Секретарев и др. / Волноводно-щелевая антенна…
__________________________________________________________________________________________________________________
492
Fig. 7. A photo of the antenna system integrated to a
transmitter/receiver module
Each antenna section forms the radiation
pattern with the beamwidth of 10º in the elevation
plane and 2º in the azimuth plane. The gain of each
antenna section is over 30 dB. The antenna beams are
displaced with the step of 16º in the elevation plane
providing the total observation sector of about 60º as
illustrated in Fig. 8.
Fig. 8. Antenna pattern in the elevation plane
The sections are switched electrically by
using an original high power reciprocal SP4T switch
based on p-i-n diodes. The switch is based on three
waveguide Y-junctions connected as a binary tree
shown in Fig. 9.
The junctions of the second stage of the tree
are ended by a reflective switches based on p-i-n
diodes. Each switch utilizes two diodes included in
resonant circuitry and operates in so-called inverse
mode, when a high reflection occurs while the diode
is biased in the reverse direction. The maximum peak
power for such configuration is as high as 2,5 kW
with the switching time as low as 1 µsec. It should be
stressed that the proposed switch design minimizes
the amplitude of the RF voltage across the diodes.
The lengths of each branch of the Y-junctions are
adjusted in order to optimize performance of the
switch. The bandwidth of the switch is about ±3 %.
Fig. 9. A block-diagram of SP4T switch
Principal parameters of the antenna system
are summarized in table below. The produced
antenna along with other hardware and software
solutions has enabled for achieving rather attractive
characteristics of the complete radar system, which is
the helicopter collision avoidance, surveillance, and
weather radar [4].
Parameter Value
Operation frequency range, GHz 35±0,2
Number of antenna sections 4
Antenna section switching electrical
Antenna section switching time, µsec 2
Antenna switch decoupling, dB > 25
Antenna switch insertion losses <1,5 dB
Commutated pulsed power, kW 5 (max)
Commutated averaged power, W 5 (max)
Beam width of in H-plane, deg 2
Beam width of in E-plane, deg 10
Beam scanning range in E-plane, deg 60
Antenna gain, dB >30
Sidelobe level, dB <–20 dB
VSWR <1,2
Dimension of the antenna section, mm3 310×72×9
Weight of the antenna section, kg 0,3
Conclusions. An original electrically
switchable, Ka-band antenna array system has been
developed, produced, and tested. A high
reproducibility of the antenna characteristics have
been observed along with a high degree of their
compliance with the simulation results. The antenna
system has been designed for airborne application. It
is used in a helicopter collision avoidance,
surveillance, and weather radar.
С. С. Секретарев и др. / Волноводно-щелевая антенна…
__________________________________________________________________________________________________________________
493
The authors would like to thank A. Popov
and L. Shevtsova for their valuable contributions to
this work.
1. Glamazdin V. V., Lukin K. A., Skresanov V. N. Improvement
of basic synthetic aperture pattern characteristic by
comparison method // Radiophisics and Electronics. – 2005. –
10, No. 1. – P. 77-84.
2. Sekretarov S. S., Vavriv D. M., Natarov M. P., Glamaz-
din V. V. Development of a Ka-band slotted antenna array /
Proc. of MSMW’07, Kharkov. – 2007. – 2. – P. 672-674.
3. Antennas and Microwave Devices (Design of the Phase
Antenna Arrays) / Editor D. I. Voskresenskiy. – Moscow.:
Radio and Sviaz. – 1981. – P. 432 (in Russian).
4. Volkov V. A., Vavriv D. M., Kozhin R. V. et al. A Ka-band,
magnetron based scanning radar for airborne applications /
Proc. of EUMW 2007, Munich – 2007. – P. 1465-1468.
ВОЛНОВОДНО-ЩЕЛЕВАЯ АНТЕННА,
СИСТЕМА Ka-ДИАПАЗОНА
С ЭЛЕКТРИЧЕСКИМ СКАНИРОВАНИЕМ
ЛУЧА
С. С. Секретарев, Д. М. Ваврив, В. А. Волков,
М. П. Натаров, В. В. Гламаздин
В работе представлена оригинальная конструкция
волноводно-щелевой антенной системы Ka-диапазона с
электрическим сканированием луча. Система состоит из
четырех одинаковых секций, которые подключены к приемо-
передатчику через мультипольный p-i-n переключатель
большой мощности. Предложенный p-i-n переключатель
позволяет осуществлять быстрое электрическое сканирование
луча антенны, что существенно расширяет область
применения антенной системы. Разработанная антенная
система была применена в радаре, предназначенном для
обеспечения безопасности полета вертолетов, а также
контроля метеоусловий. В статье описаны свойства антенной
системы, приведены ее основные характеристики, результаты
тестирования и интеграции антенны в радар.
Ключевые слова: волноводно-щелевая антенна,
антенна Ka-диапазона, p-i-n переключатель, радар обеспечения
безопасности полетов.
ХВИЛЕВІДНО-ЩІЛИННА АНТЕНА,
СИСТЕМА Ka- ДІАПАЗОНУ
З ЕЛЕКТРИЧНИМ СКАНУВАННЯМ ПРОМЕНЯ
С. С. Секретарьов, Д. М. Ваврів, В. А. Волков,
М. П. Натаров, В. В. Гламаздін
У роботі представлено оригінальну конструкцію
хвилевідно-щілинної антенної системи Ka-діапазону з
електричним скануванням променя. Система складається з
чотирьох однакових секцій, які підключені до приймача-
передавача через мультипольний p-i-n перемикач великої
потужності. Запропонований p-i-n перемикач дозволяє
здійснювати швидке електричне сканування променя антени,
що істотно збільшує сферу застосування антенної системи.
Розроблену антенну систему було застосовано в радарі,
призначеному для забезпечення безпеки польоту гелікоптерів,
а також контролю метеоумов. У статті описано властивості
антенної системи, наведено її основні характеристики,
результати тестувань та інтеграції антени в радар.
Ключові слова: хвилевідно-щілинна антена, антена
Ka-діапазону, p-i-n перемикач, радар забезпечення безпеки
польотів.
Рукопись поступила 3 июня 2008 г.
|
| id | nasplib_isofts_kiev_ua-123456789-10793 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1028-821X |
| language | English |
| last_indexed | 2025-11-28T03:30:23Z |
| publishDate | 2008 |
| publisher | Electrically switchable, ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ. |
| record_format | dspace |
| spelling | Sekretarov, S.S. Vavriv, D.M. Volkov, V.A. Natarov, M.P. Glamazdin, V.V. 2010-08-06T15:28:24Z 2010-08-06T15:28:24Z 2008 Electrically switchable, Ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ. 1028-821X https://nasplib.isofts.kiev.ua/handle/123456789/10793 537.86:621.396.677.71 An original electrically switchable, Ka-band slotted waveguide antenna array system has been recently developed, produced, and tested. The system consists of four identical sections, which are connected to a radar transmitter/receiver by means of a high-power, multipole p-i-n switch. The introduced p-i-n switch enables for a fast electrical scanning of the antenna beam what essentially extends possible areas of the antenna system application. The antenna system is used in a helicopter collision avoidance, surveillance, and weather radar. This paper describes design features of the antenna system, its main characteristics, results of its testing, and the antenna integration in the radar. У роботі представлено оригінальну конструкцію хвилевідно-щілинної антенної системи Ka-діапазону з електричним скануванням променя. Система складається з чотирьох однакових секцій, які підключені до приймача-передавача через мультипольний p-i-n перемикач великої потужності. Запропонований p-i-n перемикач дозволяє здійснювати швидке електричне сканування променя антени, що істотно збільшує сферу застосування антенної системи. Розроблену антенну систему було застосовано в радарі, призначеному для забезпечення безпеки польоту гелікоптерів, а також контролю метеоумов. У статті описано властивості антенної системи, наведено її основні характеристики, результати тестувань та інтеграції антени в радар. В работе представлена оригинальная конструкция волноводно-щелевой антенной системы Ka-диапазона с электрическим сканированием луча. Система состоит из четырех одинаковых секций, которые подключены к приемо-передатчику через мультипольный p-i-n переключатель большой мощности. Предложенный p-i-n переключатель позволяет осуществлять быстрое электрическое сканирование луча антенны, что существенно расширяет область применения антенной системы. Разработанная антенная система была применена в радаре, предназначенном для обеспечения безопасности полета вертолетов, а также контроля метеоусловий. В статье описаны свойства антенной системы, приведены ее основные характеристики, результаты тестирования и интеграции антенны в радар. The authors would like to thank A. Popov and L. Shevtsova for their valuable contributions to this work. en Electrically switchable, ka-band slotted waveguide antenna array system / S.S. Sekretarov, D.M. Vavriv, V.A. Volkov, M.P. Natarov, V.V. Glamazdin // Радіофізика та електроніка. — 2008. — Т. 13, № 3. — С. 489-493. — Бібліогр.: 4 назв. — англ. Электродинамика СВЧ Electrically switchable, Ka-band slotted waveguide antenna array system Волноводно-щелевая антенна, система Ka-диапазона с электрическим сканированием луча Хвилевідно-щілинна антена, система Ka-діапазону з електричним скануванням променя Article published earlier |
| spellingShingle | Electrically switchable, Ka-band slotted waveguide antenna array system Sekretarov, S.S. Vavriv, D.M. Volkov, V.A. Natarov, M.P. Glamazdin, V.V. Электродинамика СВЧ |
| title | Electrically switchable, Ka-band slotted waveguide antenna array system |
| title_alt | Волноводно-щелевая антенна, система Ka-диапазона с электрическим сканированием луча Хвилевідно-щілинна антена, система Ka-діапазону з електричним скануванням променя |
| title_full | Electrically switchable, Ka-band slotted waveguide antenna array system |
| title_fullStr | Electrically switchable, Ka-band slotted waveguide antenna array system |
| title_full_unstemmed | Electrically switchable, Ka-band slotted waveguide antenna array system |
| title_short | Electrically switchable, Ka-band slotted waveguide antenna array system |
| title_sort | electrically switchable, ka-band slotted waveguide antenna array system |
| topic | Электродинамика СВЧ |
| topic_facet | Электродинамика СВЧ |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/10793 |
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