Ultra Wideband Dipole Antenna
This paper considers the antenna-feeder device which helps to realize a new method of antenna excitation. This method enables to transfer dipole antennas into the ultra-wideband category. The paper also demonstrates the experimental characteristics.
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| Дата: | 2002 |
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Радіоастрономічний інститут НАН України
2002
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| Назва видання: | Радиофизика и радиоастрономия |
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| Цитувати: | Ultra Wideband Dipole Antenna / L.D. Bakhrakh, V.F. Los', A.N. Shamanov // Радиофизика и радиоастрономия. — 2002. — Т. 7, № 4. — С. 368-371. — Бібліогр.: 10 назв. — англ. |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
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irk-123456789-1223382017-07-03T03:03:22Z Ultra Wideband Dipole Antenna Bakhrakh, L.D. Los', V.F. Shamanov, A.N. This paper considers the antenna-feeder device which helps to realize a new method of antenna excitation. This method enables to transfer dipole antennas into the ultra-wideband category. The paper also demonstrates the experimental characteristics. В этой статье рассматривается антенно-фидерное устройство, в котором реализован новый метод возбуждения антенны. Это позволяет использовать дипольную антенну в качестве сверхширокополосной. У цій статті розглянуто антенно-фідерний пристрій, у якому реалізовано новий метод збудження антени. Це дозволяє використовувати дипольну антенну у якості надширокосмугової. 2002 Article Ultra Wideband Dipole Antenna / L.D. Bakhrakh, V.F. Los', A.N. Shamanov // Радиофизика и радиоастрономия. — 2002. — Т. 7, № 4. — С. 368-371. — Бібліогр.: 10 назв. — англ. 1027-9636 http://dspace.nbuv.gov.ua/handle/123456789/122338 en Радиофизика и радиоастрономия Радіоастрономічний інститут НАН України |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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English |
| description |
This paper considers the antenna-feeder device which helps to realize a new method of antenna excitation. This method enables to transfer dipole antennas into the ultra-wideband category. The paper also demonstrates the experimental characteristics. |
| format |
Article |
| author |
Bakhrakh, L.D. Los', V.F. Shamanov, A.N. |
| spellingShingle |
Bakhrakh, L.D. Los', V.F. Shamanov, A.N. Ultra Wideband Dipole Antenna Радиофизика и радиоастрономия |
| author_facet |
Bakhrakh, L.D. Los', V.F. Shamanov, A.N. |
| author_sort |
Bakhrakh, L.D. |
| title |
Ultra Wideband Dipole Antenna |
| title_short |
Ultra Wideband Dipole Antenna |
| title_full |
Ultra Wideband Dipole Antenna |
| title_fullStr |
Ultra Wideband Dipole Antenna |
| title_full_unstemmed |
Ultra Wideband Dipole Antenna |
| title_sort |
ultra wideband dipole antenna |
| publisher |
Радіоастрономічний інститут НАН України |
| publishDate |
2002 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/122338 |
| citation_txt |
Ultra Wideband Dipole Antenna / L.D. Bakhrakh, V.F. Los', A.N. Shamanov // Радиофизика и радиоастрономия. — 2002. — Т. 7, № 4. — С. 368-371. — Бібліогр.: 10 назв. — англ. |
| series |
Радиофизика и радиоастрономия |
| work_keys_str_mv |
AT bakhrakhld ultrawidebanddipoleantenna AT losvf ultrawidebanddipoleantenna AT shamanovan ultrawidebanddipoleantenna |
| first_indexed |
2025-07-08T21:32:21Z |
| last_indexed |
2025-07-08T21:32:21Z |
| _version_ |
1837115999915081728 |
| fulltext |
Radio Physics and Radio Astronomy, 2002, v. 7, No. 4, pp. 368-371
ULTRA WIDEBAND DIPOLE ANTENNA
L.D. Bakhrakh, V.F. Los’, A.N. Shamanov
Moscow Scientific Research Institute of Instrument Engineering
34 Kutuzov Ave, 121170, Moscow, Russia
Tel: (095) 2490704, Fax: (095) 9331563
E-mail: mnp3@ccas.ru
This paper considers the antenna-feeder device which helps to realize a new method of antenna excitation.
This method enables to transfer dipole antennas into the ultra-wideband category. The paper also demonstrates
the experimental characteristics.
One of the existing problems in the modern ultra
wideband wirelesses systems is the absence of any
ultra wideband antenna radiator like Hertz dipole.
It is known that for all the available type of di-
pole antennas the wideband matching is a very diffi-
cult task as, under the existing methods of excitation,
the dipole has a narrow bandwidth of the matching
determined by the boundary conditions. For example,
for the electric dipole it is the abruption of a regular
line, where there is the condition of standing wave
currents on the arms of the dipole.
It is necessary to note that it is exactly by stand-
ing wave currents is established a reactive nearfield,
as, according to the Theorem of equivalence, the
field round the dipole is determined by the surface
equivalent currents on some surface S inside which
is the dipole (Fig. 1).
Dipole antennas appear to be similar to reso-
nance circuits with high quality-factor, therefore they
have the frequency band 25-50 %.
All the known ways of reduction of the depend-
ence of the input impedance on frequency by lower-
ing the wave impedance of the vibrator, by smooth
variation of its cross-section, by correction of the
input impedance of the vibrator or manufacturing the
vibrator on the principle of the electromagnetic simi-
larity, lead in a certain extent to increased overall
dimensions of the antenna. Besides it is always rec-
ognized that the radiation of electric dipole is most
efficient when the length of the vibrator arm is about
a quarter of the radiated wavelength 1/4l ≈ ; which
is equivalent to the process in the oscillator circuit
with losses lR .
The same model, with reactive and active field
components, is used as a model of a nearfield of the
dipole, the reactive component of which equals zero
at resonance. Then all the electromagnetic field
power is collected by the active part of the near-field
or the circuit l inpR R= . The voltage rU and current
rI in the circuit oscillate in phase and /r r lU I R= .
This is equivalent to that in the near-field of the
dipole on surface S (Fig. 1) the electrical and mag-
netic components also oscillate in phase at any reso-
nance frequency. In this way is satisfied the radiation
condition:
, ,/s r s r sE H W= ,
where sW – wave impedance of the wave front of a
traveling wave near the surface S .
In the far-field region of the dipole the condition
of radiation /x yE H W= is valid for all frequen-
cies; which evidences that at any frequency the field
carries over the real power of that part of the oscilla-
tor power which has not returned to the oscillator.
Thus, for the ultra wideband antenna matching it
is required to reduce essentially in the given band a
quasi-static field near the radiation surface of the
antenna. It is possible to reach the validity of the
equality /x yE H W= in a near-field region. It is
difficult to do, and impossible at all for the existing
methods of excitation as long as the exciting current
on the surface of antenna is defined by the boundary
G
2l
S
1ϕ
1r
1θ
у
r
ϕ
θ
x
z
Fig. 1.
Ultra Wideband Dipole Antenna
Radio Physics and Radio Astronomy, 2002, v. 7, No. 4 369
conditions: by the abruption or a short-circuit of a
regular line.
The ultra wideband matching of the dipole
shown in Fig. 2 is achieved with the aid of the match-
ing and phase-shifting antenna-feeder device 1 exe-
cuted on a coupled line. At that in the feeder line of
antenna 2, with the electromagnetically coupled sepa-
rate conductors 3 and 4, there are the wave oscilla-
tions inherent to a coupled line: the even and odd
modes. On the surface of the radiating arms of the
dipole 5 these modes produce the electromagnetic
field in which the vector of electric field E on one
arm’s surface and the vector of magnetic field H on
the other arm’s surface oscillate in phase concerning
the oscillator.
As the even and odd oscillations on the surface
of the dipole are independent oscillations with wave
impedances oeZ and ooZ , they can be presented as
separate links loaded with the wave impedance of
free space W .
As in coupled lines the wave impedance W
obeys inequality
oo oeZ W Z> > ,
in this case the waves reflected from loads have the
opposite signs and are cancelled at the input of the
oscillator G because / 1ooW Z < and
/ 1oeW Z > ; and when 2
oo oeZ Z W= , the waves
have equal amplitudes also. Therefore the broadband
matching is achieved in the dipole (Fig. 2). In Fig. 3
and Fig. 4 there are the electric and magnetic (as a
current loop) dipoles in which the double-mode way
of excitation of the currents in the radiator is used.
Their experimental frequency characteristics SWR in
Fig. 5 confirm that the dipoles are ultra wideband.
Therefore, it is fairly easy to expand the band of
the matching and shift it towards the long waves. At
this the radiation occurs from the arms of the dipole 2
whose length is much less than half a wavelength
2 /2l λ The conditions imposed on the stretch 2
of the transmission line and on the radiation elements
of the antenna, Fig. 2, allow to establish in the near-
1
5
2
4
3
Fig. 2.
80
20
Fig. 3.
D=260
Fig. 4.
1
2
3
4
5
6
7
8
70 11
1
17
5
23
5
28
0
33
5
39
0
47
0
54
0
62
0
70
0
78
0
90
5
97
0
11
10
15
70
F,MHz
SWR
Fig.3
Fig.4
Fig. 5.
L.D. Bakhrakh, V.F. Los’, A.N. Shamanov
370 Radio Physics and Radio Astronomy, 2002, v. 7, No. 4
field the wave environment where the tangential
components sE and sH in a mixed mode, tending in
the limit to standing waves, form such vector field
regarding the oscillator that the radiation condition is
valid as
/x yE H W= .
But this matching condition here, in the absence
of losses, determines the radiation condition of the
dipole determined by relationship [1]:
( )( ) 2 2
2 2 1/ /s s s oe oo GE H E H Z Z W Z= = =s1 , (1)
Thus, the in-phase oscillations of tangential compo-
nents 1sE , 1sH and 2sE , 2sH near the surface S of
the dipole occur under the condition of the matching
of the equivalent bridge circuit – 2
oe ooZ Z W=
on S . Then, according to the Uniqueness theorem,
one can tell that at any point of the field the in-phase
oscillation of two independent modes occurs; and the
coupling between their wave impedances –
2
1 2Z Z W= – is invariant to the matching condition.
And in any band and any point of the field there is a
traveling wave and there are no backward waves
concerning the oscillator ( GZ ) or viewpoint in front
of the antenna (W ). Consequently, the relationship
(1) provides the radiation condition of the antenna.
By the circuit theory, if the input characteristics
of the dipole impedances 1Z and 2Z are related as
2
1 2Z Z K= , where K is a real number having the
dimension of resistance, such dipoles are dual or
backward.
In electromagnetics such dipoles are known as
the electrical and magnetic ones. The processes in
these dipoles, though different, have similar in shape
quantitative features. Therefore the offered dipole, in
distinction, e.g., from the ordinary electric dipole,
radiates not only the usual electric vector E but also
the electric vector E which corresponds to the mag-
netic dipole radiation.
Thus, on the surface of the dipole are to be ex-
cited the electric and “magnetic” currents which ex-
cite the orthogonal electromagnetic fields generating
a traveling wave.
This orthogonality of the fields is represented in
the directivity diagrams of the electric dipole, Fig. 3,
for two polarizations of the electric vector E :
( )Eω ω , Fig. 6, that is directed along the dipole axis
(i.e. along axis Ox ) and ( )E vϕ , Fig. 7, that is per-
pendicular to the dipole axis (i.e. along axis Oy ).
And also for the magnetic dipole, Fig. 4, the directiv-
ity diagrams are with two polarizations of vector E :
( )Eω ω , Fig. 8, and ( )E vϕ , Fig. 9. The initial direc-
tion 0° is that of axis Oz .
Thus, there are simultaneously the electric and
magnetic currents as regards the oscillator in the di-
-20
-15
-10
-5
0
0 30 60 90 120 150 180 210 240 270 300 330
A
m
pl
itu
de
, d
B
4400MHz
2420MHz
820MHz
540MHz
deg
Fig. 6.
-20
-15
-10
-5
0
0 30 60 90 120 150 180 210 240 270 300 330
4400MH
z
2420MH
z
820MHz
540MHz
A
m
pl
itu
de
, -
dB
deg
Fig. 7.
-20
-15
-10
-5
0
0 30 60 90 120 150 180 210 240 270 300 330
A
m
pl
itu
de
,-d
B
4400MHz
2400MHz
1200MHz
540MHz
deg
Fig. 8.
-20
-15
-10
-5
0
0 30 60 90 120 150 180 210 240 270 300 330
4400MHz
2400MHz
1200MHz
540MHz
A
m
pl
itu
de
,-d
B
deg
Fig. 9.
Ultra Wideband Dipole Antenna
Radio Physics and Radio Astronomy, 2002, v. 7, No. 4 371
pole; which is confirmed by the calculation and ex-
periment.
From the above said the following conclusions
are to be drawn up:
1. The offered small-sized vibrator has a very wide
band of the matching by the input characteristic
SWR, and the directivity diagrams have the steady
shape and amplitude in the band with the overlap-
ping 10:1.
2. The antenna-feeder device of the dipole estab-
lishes two independent oscillations of the electro-
magnetic field in the power line and on the radia-
tion surface of the dipole.
3. There are the flowing currents in the dipole which,
as regards the properties of the directivity diagram
for vector E , can be referred to as electrical and
“magnetic” currents. Therefore the dipole radiates
two polarizations – the horizontal and vertical
ones.
4. The separate independent wave modes on the di-
pole surface are in the condition of a standing
wave whereas the condition of the abruption of a
line is valid.
5. The appearance in the antenna near-field of a trav-
eling wave under the condition a standing wave of
currents on the surface of its radiator is determined
by the presence on the surface of the even and un-
even modes of oscillations which are coupled by
the matching condition.
6. The electric vector E of one mode and the mag-
netic vector H of the other oscillate in phase on
the different arms of the dipole. Therefore, the
conditions of proportionality of the fields E and
H in the near-field region of the dipole are valid,
and the Poynting vector is real.
7. The construction of the antenna-feeder device for
the excitation of a traveling wave in dipole an-
tenna is provided, with the ultra wideband of the
matching [8,9].
8. The dipole antenna has the new qualities which
allow to include it into the class of ultra wideband
antennas.
References
1. N.V. Zernov, G.V. Merkulov. Antennas in the mode
of radiation (reception) of the ultra wideband signals.
Zarubezhnaya radioelectro-nika, №1, (1991) (in Rus.).
2. H.F. Harmuth. Nonsinusoidal Waves for Radar and
Radio Communication (Academic Press, New York,
1981; Radio i Svyaz’, Moscow, 1985).
3. L.Yu. Astanin, A.A. Kostylev. Foundations of the
Ultra Wideband Measurings (Radio i Svyaz’, Mos-
cow, 1989) (in Rus.).
4. G.T. Markov, D.M. Sazonov. Antennas. Moscow,
Energiya (1975) (in Rus.).
5. V.V. Nickolsky. Electromagnetic field theory.
Мoscow, Vysshayaя shkola. (1961) (in Rus.).
6. K. Walter. Traveling wave antennas. Мoscow, Ener-
giya (1970) (in Rus.).
7. N.N. Fedorov. Electrodynamics foundations. Мoscow,
Vysshayaя shkola, (1980) (in Rus.)
8. А.N. Shamanov. The method of the dipole band wid-
ening. The frequency-independent dipole. Antennas.
1, 42 (1991) (in Rus.).
9. Patents. RU №2070356, RU №2132587.
10. Engineer electrophysics foundations. Editor P.А. Ion-
kin. Мoscow, Vysshayaя shkola (1972) (in Rus.).
СВЕРХШИРОКОПОЛОСНАЯ
ДИПОЛЬНАЯ АНТЕННА
Л.Д. Бахрах, В.Ф. Лось, А.Н. Шаманов
В этой статье рассматривается антенно-фидерное
устройство, в котором реализован новый метод возбу-
ждения антенны. Это позволяет использовать диполь-
ную антенну в качестве сверхширокополосной.
НАДШИРОКОСМУГОВА ДИПОЛЬНА
АНТЕНА
Л.Д. Бахрах, В.Ф. Лось, А.М. Шаманов
У цій статті розглянуто антенно-фідерний при-
стрій, у якому реалізовано новий метод збудження
антени. Це дозволяє використовувати дипольну антен-
ну у якості надширокосмугової.
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