RU169100U1 - REDUCED ASYMMETRIC VIBRATOR - Google Patents

Abstract

The utility model relates to an element of radio communication - antenna technology and can be used as an element for creating phased antenna arrays of short-wave (KB) and ultra-short-wave (VHF) ranges in conditions of a limited surface of their placement, for example, on ships and ships. The vibrator contains a high-frequency generator 4 connected through a power amplifier 5 by a coaxial cable line 6 with a vertical asymmetric vibrator (1, 2 and 3), which is mounted on the insulator 2 with the metal body of the antenna 12 and the ship's hull. The radiating element of an asymmetric vibrator consists of two components, isolated from each other, with a total total length of three meters = 3, the lower radiating element of length = 2.7 meters is conductive (metal) and cylindrical, structurally inside the hollow, located in its cavity impedance conversion control system 15, which allows you to rebuild the input inductance of the antenna, in other words, to extend or shorten the length of the antenna, tuning the antenna in resonance with the frequency of the generator. The input of the control system for converting impedances 15 is connected by a coaxial cable 6 through a power amplifier 5 to the output of a high-frequency generator 4. The technical result consists in providing constant efficiency in the entire range of operating frequencies. 2 s.p. f-ly, 13 ill.

Description

The utility model relates to an element of radio communication - antenna technology and can be used as an element for creating phased antenna arrays of short-wave (KB) and ultra-short-wave (VHF) ranges in conditions of a limited surface of their placement, for example, on ships and ships.

It is known that an asymmetric vibrator (or pin) is widely used, based on its high weight and size characteristics and directional properties. The pin occupies a small area when placed, therefore it is used everywhere on ships and ships, and in significant quantities on board ships (several dozen).

, в виде проводящего прямолинейного проводника цилиндрической формы, генератора 3 и заземлителя - 2, при этом выход генератора ЭДС(~U_A) - 3 подключен одной клеммой к излучающему элементу 1, а другой клеммой - к заземлителю 2.In FIG. 1 shows an asymmetric vibrator or pin, which has a radiating element - 1 length

, in the form of a conductive rectilinear conductor of a cylindrical shape, generator 3 and ground electrode - 2, while the output of the EMF generator (~ U _A ) - 3 is connected by one terminal to the radiating element 1, and the other terminal to the ground electrode 2.

In FIG. 2 gives options for using an asymmetric vibrator.

In FIG. 3 gives a model for determining the antenna’s own capacitance.

In FIG. 4 is a graph of the normalized potential distribution function along the length of the antenna.

In FIG. 5, an asymmetric vibrator with a remote extension coil included in the gap of the radiating element of the antenna is given.

In FIG. 6 shows the current distribution along the length of the radiating element of an asymmetric vibrator.

In FIG. 7 is a graph of the difference of the integral functions of the current.

In FIG. Figure 8 shows graphs of radiation resistance and loss resistance, depending on the connection point of the extension coil or inductive resistance.

In FIG. Figure 9 shows the antenna efficiency graphs for various values of the Q factor of the inductive element included as an extension coil in the radiating element of the asymmetric vibrator.

In FIG. 10 shows graphs of the gain of the radiated power from the coordinate of the inclusion of the inductive element and the quality factor of the inductance.

=3, нижний излучающий элемент длиной

=2,7 метра является проводящей (металлической) и цилиндрической формы, конструктивно внутри полой, в ее полости располагается система управления преобразования импедансов 15, позволяющая перестраивать входное индуктивное сопротивление антенны, иными словами удлинять или укорачивать длину антенны, настраивая антенну в резонанс с частотой генератора; вход системы управления преобразования импедансов 15 соединен коаксиальным кабелем 6 через усилитель мощности 5 с выходом высокочастотного генератора 4; толщина стенок цилиндра определяется районом плавания судна и принята равной d₁=3 сантиметра; верхний излучающий элемент несимметричного вибратора представляется проводящим цельнометаллическим стержнем длиной

=30 сантиметров и сечением d₂=3 сантиметра, закрепленным своим основанием через плоское высокоомное сопротивление R с верхней частью нижнего излучающего элемента несимметричного вибратора 1.In FIG. 11 shows a design of a model of a shortened asymmetric vibrator containing a high-frequency generator 4 connected via a power amplifier 5 with a coaxial cable line 6 to a vertical asymmetric vibrator (1, 2, and 3), which is mounted on the insulator 2 with the metal body of the antenna 12 and the ship's hull; the radiating element of an asymmetric vibrator consists of two components, isolated from each other, with a total total length of three meters

= 3, lower radiating element of length

= 2.7 meters is conductive (metal) and cylindrical in shape, hollow structurally, in its cavity there is an impedance conversion control system 15 that allows you to rebuild the input inductive impedance of the antenna, in other words, to extend or shorten the length of the antenna, adjusting the antenna to resonance with the generator frequency ; the input of the impedance conversion control system 15 is connected by a coaxial cable 6 through a power amplifier 5 to the output of a high-frequency generator 4; the wall thickness of the cylinder is determined by the navigation area of the vessel and taken equal to d ₁ = 3 centimeters; the upper radiating element of the asymmetric vibrator is represented by a conductive all-metal rod of length

= 30 centimeters and a cross section d ₂ = 3 centimeters, fixed with its base through a flat high-impedance resistance R with the upper part of the lower radiating element of the asymmetric vibrator 1.

In FIG. 12 shows a control system for converting impedances 15, contains a gyrator 11, a frequency-voltage converter 10, and a frequency reduction converter 9 with a system 15 connected in parallel to load 2 into an asymmetric vibrator consisting of two elements 1 and 3 and powered by a high-frequency generator 4 through a power amplifier 5 and coaxial cable 6.

In FIG. 13 shows a model of a gyrator, which contains the first op-amp 1 and the second op-amp 2 operational amplifiers; first R1, second R2, third R3 and fourth R4 resistors, load capacitance C and varicap Vp.

длина излучающего элемента вибратора с диаметром сечения

. Длина излучающего элемента вибратора играет важную роль в излучающих качествах штыря. Резонансная частота ƒ₀ или частота настройки ƒ_нас=ƒ₀ антенны связана с резонансной длиной волны λ₀ и длиной излучающего элемента вибратора следующими соотношениями: 4⋅

=λ₀; ƒ₀=С/λ₀, где С - скорость света (3⋅10⁸, м/с). Режим работы с параметрами 4⋅

=λ₀; ƒ₀=С/λ₀ называется режимом собственной длины волны. Коэффициент перекрытия для штыря равен 1,2. Поэтому антенны несимметричного вибратора работают в узкой полосе частот.In FIG. 1 shows a physical model of an asymmetric vibrator located along the X axis.

the length of the radiating element of the vibrator with a diameter of section

. The length of the radiating element of the vibrator plays an important role in the radiating properties of the pin. The resonant frequency ƒ ₀ or the tuning frequency ƒ _us = ƒ _{0 of the} antenna is related to the resonant wavelength λ ₀ and the length of the radiating element of the vibrator with the following relationships: 4⋅

= λ ₀ ; ƒ ₀ = С / λ ₀ , where С is the speed of light (3⋅10 ⁸ , m / s). Operating mode with parameters 4⋅

= λ ₀ ; ƒ ₀ = C / λ ₀ is called the mode of its own wavelength. The overlap coefficient for the pin is 1.2. Therefore, single-ended vibrator antennas operate in a narrow frequency band.

An example of a low work efficiency can be seen for a pin with setting a given length, for working in its own length mode or in a range close to this mode:

=4 метра в режиме собственной длины настраивается на частоту 1875 кГц (или 18,75 МГц) и работает в диапазоне частот от 17 до 24 МГц с КПД не хуже 0,2;1. for example, with the length of the emitting element of the pin

= 4 meters in the intrinsic length mode it is tuned to a frequency of 1875 kHz (or 18.75 MHz) and works in the frequency range from 17 to 24 MHz with an efficiency of no worse than 0.2;

=5 метров в режиме собственной длины настраивается на частоту 15 МГц и работает в диапазоне частот от 13 до 17 МГц с КПД не хуже 0,2;2. with the length of the emitting element of the pin

= 5 meters in intrinsic length mode tunes to a frequency of 15 MHz and operates in the frequency range from 13 to 17 MHz with an efficiency of no worse than 0.2;

=7 метров в режиме собственной длины настраивается на частоту 10,71 МГц и работает в диапазоне частот от 9 до 12 МГц с КПД не хуже 0,2;3. with the length of the radiating element of the pin

= 7 meters in its own length mode, tunes to a frequency of 10.71 MHz and operates in the frequency range from 9 to 12 MHz with an efficiency of no worse than 0.2;

=8 метров в режиме собственной длины настраивается на частоту 9,375 МГц и работает в диапазоне частот от 7,5 до 10 МГц с КПД не хуже 0,2;4. with the length of the radiating element of the pin

= 8 meters in its own length mode, tunes to a frequency of 9.375 MHz and operates in the frequency range from 7.5 to 10 MHz with an efficiency of no worse than 0.2;

=10 метров в режиме собственной длины настраивается на частоту 7.5 МГц и работает в диапазоне частот от 5 до 8 МГц с КПД не хуже 0,2;5. with the length of the radiating element of the pin

= 10 meters in its own length mode, tunes to a frequency of 7.5 MHz and operates in the frequency range from 5 to 8 MHz with an efficiency of at least 0.2;

=25 метров в режиме собственной длины настраивается на частоту 3 МГц и работает в диапазоне частот от 3 до 5 МГц с КПД не хуже 0,2.6. with the length of the radiating element of the pin

= 25 meters in its own length mode, tunes to a frequency of 3 MHz and operates in the frequency range from 3 to 5 MHz with an efficiency of no worse than 0.2.

Thus, to work in the KB range (from 3 to 30 MHz), it is necessary to have at least 7 whip antennas, which are indicated: so 4-meter as W4 (four-meter pin); 5-meter - Ш5; 7-meter - Ш7; 8-meter - Ш8; 10-meter - Ш10; 25-meter - Ш25.

However, such a number of pin antennas is not advisable to use because of the complexity of their placement, therefore, complex designs of pins are created in order to expand the working range of their use.

In FIG. Figure 2 shows typical options for improving the design of antennas to expand the range properties of the antenna. Communication systems operating in the short-wave range of the radio frequency spectrum everywhere use vertical asymmetric vibrators (pins) of almost the same design. Their difference consists only in the fact that they use a different number of concentrated inductances 3 (L _K ) included, as well as capacitive pins at the end of the radiating element of the antenna 4 and 5.

The embodiment of FIG. 2 (a) represents the design of a pin operating in a narrow frequency band and contains a radiating element 1 and an earthing switch 2, a ~ U _A generator is connected to the antenna terminals “a” and “b”. The following antenna was developed for ships:

- ship transmitting antenna-pin type AS-8C, having various options for implementation depending on their location and presented in the monograph “Ship antennas” M.V. Vershkova and O.B. Peacemaking on pp. 271-272, - L .: ed. "Shipbuilding", 1990;

- a ship's transmitting antenna called “Antenna-mast”, is a mast isolated from the deck (usually with top feed with a grounded mast) 25 meters high, the radiating element is 1 and the ship deck is an earthing switch 2. The antenna operating range is from 1 , 5 MHz to 4.5 MHz. The antenna refers to the analogue "Antenna mast", patent No. 191651. USSR, MKI H04d. "Antenna mast", patent No. 816355, USSR, MKI H01Q 1/34. The disadvantages of the antenna are: a very small coefficient of overlap of the range of operating frequencies and large weight and size characteristics.

=10 метров, комплексное сопротивление включено на высоте примерно 7 метров. Рабочий диапазон антенны от 4 до 25 МГц. Устанавливается на всех судах под названием «Широкополосная передающая антенна - 11» - ШПА-11 с RL - включением (представлена в монографии «Судовые антенны» М.В. Вершкова и О.Б. Миротворского на стр. 139-141, - Л.: изд. «Судостроение», 1990). Недостатками антенны являются: неравномерность частотной характеристики входного сопротивления антенны и большие массогабаритные характеристики.The embodiment of FIG. 2 (b) is an asymmetric vibrator with complex resistances Z (R + jωL _K ) included in the wire break. The length of the radiating element of the antenna

= 10 meters, the complex resistance is turned on at a height of about 7 meters. The operating range of the antenna is from 4 to 25 MHz. It is installed on all vessels under the name "Broadband Transmitting Antenna - 11" - ShPA-11 with RL - inclusion (presented in the monograph "Ship Antennas" by M.V. Vershkov and O. B. Mirotovsky on pages 139-141, - L. : ed. "Shipbuilding", 1990). The disadvantages of the antenna are: the uneven frequency response of the input impedance of the antenna and large weight and size characteristics.

The embodiment of FIG. 2 (c) is an asymmetric vibrator similar to the embodiment of FIG. 2 (b) but characterized in that there is a capacitive load 4 at the end of the radiating element of the antenna. The capacitive load compensates the inductance of the antenna in the upper part of the range, thereby expanding the range properties of the antenna in comparison with the embodiment of FIG. 2 (b). Thus, the antenna operates in the range from 4 to 30 MHz. The disadvantages of the antenna are: the uneven frequency response of the input impedance of the antenna and large weight and size characteristics.

The embodiment of FIG. 2 (e) is an asymmetric vibrator similar to the embodiment of FIG. 2 (b), but differs in that an attempt is made to extend the radiating element of the antenna by turning on the third inductance. Extension allows the use of frequencies from 3 to 25 MHz. However, additional reactivity reduces the current and reduces the efficiency of the antenna. More than three shared inductances are not used in antennas. The disadvantages of the antenna are: increased antenna resistance, uneven frequency response of the antenna input impedance and large weight and size characteristics.

=10 метров, комплексное сопротивление включено на высоте примерно 7 метров. Рабочий диапазон антенны от 5 до 30 МГц. Устанавливается на всех судах под названием «Импедансная многовибраторная передающая антенна - 11-2» - ШПА-11-2 с RL-включением и четырех вибраторов (патент СССР №285837, МКИ H01q 9/18). Для устранения неравномерности частотной характеристики входного сопротивления установлены дополнительно четыре штыря 5, которые обеспечивают выравнивание ее частотной характеристики в рабочем диапазоне частот от 5 до 30 МГц. Описание представлено в монографии «Судовые антенны» М.В. Вершкова и О.Б. Миротворского на стр. 142-150 – Л.: изд. «Судостроение», 1990.The embodiment of FIG. 2 (e) is an asymmetric vibrator with complex resistances Z (R + jωL _K ) included in the gap of the radiating wire element. The length of the radiating element of the antenna

= 10 meters, the complex resistance is turned on at a height of about 7 meters. The operating range of the antenna is from 5 to 30 MHz. It is installed on all ships under the name “Impedance Multivibrator Transmitting Antenna - 11-2” - ShPA-11-2 with RL switching and four vibrators (USSR patent No. 285837, MKI H01q 9/18). To eliminate the unevenness of the frequency response of the input resistance, four pins 5 are additionally installed, which ensure the alignment of its frequency response in the operating frequency range from 5 to 30 MHz. The description is presented in the monograph “Ship antennas” M.V. Vershkova and O.B. Peacemaking on pp. 142-150 - L .: ed. Shipbuilding, 1990.

A common parameter of these antennas is the traveling wave coefficient, which is in the range from 0.3 to 0.4, so the antenna efficiency is very low and is in the range of 0.4 to 0.2.

Communication systems operating in the short-wave range of the radio frequency spectrum everywhere use vertical asymmetric vibrators of almost the same design. Their difference consists only in the fact that they use a different number of concentrated inductances L _K , as well as capacitive pins at the end of the antenna. In this case, the electromotive force generator ~ U _A excites the current in the radiating element of the antenna, where the elements for tuning to a given frequency range may be the concentrated inductance L _K and capacitance C. The inclusion of inductances as inhomogeneities in the electrical circuit of a vertical asymmetric vibrator of more than three is not advisable. This is justified by the fact that the total inductance increases the active resistance of the wire and, as a result, reduces the current in the antenna.

(противовеса) входит составной частью в сопротивление антенны: R_A=R_Σ+

+….The range properties are influenced by the design of the counterweight (ground electrode). This is due to the fact that the grounding resistance

(counterweight) is part of the antenna resistance: R _A = R _Σ +

+ ....

: Q_A=W_A/R_A.At the same time, on the basis of the expression, it can be seen that an increase in the quality factor of the antenna reduces the operating range. The quality factor depends on the wave impedance W _A and the active resistance of the vibrator

: Q _A = W _A / R _A.

Thus, the section describes the options for typical antennas and shows the features of their design solutions that allow changing range properties. These examples provide the basis for further design changes to improve the radiating capabilities of the described antennas.

The purpose of developing a utility model is to establish a constant current in the radiating element of the antenna regardless of the operating frequency and to reduce the overall dimensions of the antenna (reduce the weight and size of the antenna). This is possible through the use of shortened asymmetric vibrators.

The radiation efficiency of short antennas.

A short antenna with certain tolerances can be considered as an elementary electric emitter. In this case, the radiation power for an elementary emitter is obtained:

² _А/λ², но

P _∑ = 40π ² I ²

² _A / λ ² , but

. Е/Н=120πWhere

. E / N = 120π

Equating the expressions of the radiation power, we can obtain:

Based on the analysis of the expressions for magnetic H and electric E components, it follows that:

;- the field strength created by the vibrator depends on the volume of the field in which it is concentrated

;

- the value of the vector quantities E and H decreases with increasing wavelength while the geometric dimensions of the emitter remain unchanged:

- the geometric dimensions of the antenna affect the field strength, therefore, reducing the size of the emitter, to increase the field strength in the volume, an increase in the current in the antenna is necessary.

The last point is used to develop a useful model of a shortened asymmetric vibrator. This means that under equal conditions, shortening the antenna, it is necessary to increase the current in it.

=10 метров, комплексное сопротивление включено на высоте примерно 7 метров. Рабочий диапазон антенны от 4 до 25 МГц. Устанавливается на всех судах под названием «Широкополосная передающая антенна - 11» - ШПА-11 с RL-включением (представлена в монографии «Судовые антенны» М.В. Вершкова и О.Б. Миротворского на стр. 139-141 – Л.: изд. «Судостроение», 1990). Недостатком антенны является: неравномерность частотной характеристики входного сопротивления антенны, низкий КПД антенны (только на резонансной частоте ƒ₀, т.е. когда 4⋅

=λ₀ и ƒ₀=С/λ₀, то КПД=0,4, а во всем остальном диапазоне меньше 0,4 и большие массогабаритные характеристики).Therefore, as a prototype, the model of the embodiment of FIG. 2 (b), which is an asymmetric vibrator with complex resistances Z (R + jωL _K ) included in the wire break. The length of the radiating element of the antenna

= 10 meters, the complex resistance is turned on at a height of about 7 meters. The operating range of the antenna is from 4 to 25 MHz. It is installed on all vessels under the name "Broadband Transmitting Antenna - 11" - ShPA-11 with RL inclusion (presented in the monograph "Ship Antennas" by M.V. Vershkov and O. B. Mirotovsky on pages 139-141 - L .: Publishing house "Shipbuilding", 1990). The disadvantage of the antenna is: uneven frequency response of the antenna input impedance, low antenna efficiency (only at the resonant frequency ƒ ₀ , i.e. when 4⋅

= λ ₀ and ƒ ₀ = C / λ ₀ , then the efficiency = 0.4, and in the rest of the range less than 0.4 and large mass and size characteristics).

The purpose of the development of a utility model is to create an antenna operating condition with a constant efficiency in the entire range of operating frequencies, which is achieved by correcting the uneven frequency response of the input impedance in the entire range of operating frequencies by turning on a controlled impedance converter or creating conditions under which the input impedance in the frequency range close the resistance of the antenna in the mode of its own wavelength or control the value of the input impedance of the antenna in the range required For a constant current in it at any frequency of the operating range; which allows to reduce the length of the radiating element and the weight of the antenna; those. creation of a shortened asymmetric vibrator with parameters no worse than the existing prototype, based on monitoring the input impedance of the antenna with the value required for the constancy of current in it at any frequency of the operating range.

и верхнего излучающего элемента 3 длиной

, общая длина излучающего элемента вибратора 3 метра

метра, верхний и нижние элементы несимметричного вибратора разделены на высоте 2,7 метра изолятором 2 длиной

, точки M-N определяют размер вертикального сечения изолятора, или изолирующего элемента несимметричного вибратора и являются изолятором между нижним элементом 1 и верхним элементом 3, соединенных через управляемый преобразователь импедансов 15; управляемый преобразователь импедансов 15 содержит гиратор 11, преобразователь понижения частоты 9, преобразователь частота-напряжение 10 (фиг. 12 и фиг. 13); в полости цилиндра 1 (фиг. 11), таким образом, располагается система управления преобразования импедансов, содержащая: гиратор 11, преобразователь понижения частоты 9 и частота-напряжение 10. Система управления позволяет на основе использования преобразователей понижения частоты 9 и частота-напряжение 10 выполнять перестройку гиратора 11, т.е. его непосредственно входного индуктивного сопротивления, включаемого параллельно изолятору 2, или входного сопротивления антенны до величины, требуемой для постоянства тока в ней на любой частоте рабочего диапазона.This goal is achieved by the fact that additionally introduced the separation of the asymmetric vibrator (Fig. 11), consisting of two parts: the lower radiating element 1 of length

and upper radiating element 3 long

, the total length of the radiating element of the vibrator 3 meters

meters, the upper and lower elements of the asymmetric vibrator are separated at a height of 2.7 meters by an insulator 2 of length

, points MN determine the size of the vertical section of the insulator, or insulating element of an asymmetric vibrator, and are an insulator between the lower element 1 and the upper element 3, connected through a controlled impedance converter 15; the controlled impedance converter 15 comprises a gyrator 11, a frequency down converter 9, a frequency-voltage converter 10 (FIG. 12 and FIG. 13); in the cavity of the cylinder 1 (Fig. 11), thus, there is an impedance conversion control system comprising: a gyrator 11, a frequency reduction converter 9 and a frequency-voltage 10. The control system allows, based on the use of frequency reduction converters 9 and a frequency-voltage 10, to perform rebuilding of the gyrator 11, i.e. its direct input inductance, connected in parallel to the insulator 2, or the input impedance of the antenna to the value required for the constancy of the current in it at any frequency of the operating range.

Shortened antennas, for a number of reasons, have worse characteristics than antennas using the natural wavelength mode. The reasons for the deterioration of the characteristics of antennas with their electric length much shorter than the resonance are described in detail in a number of sources [1, 2, 3]. However, despite its shortcomings, shortened antennas are widely used due to the fact that the location of a full-sized antenna is impossible due to a lack of working space, unsatisfactory weight and size characteristics, or other engineering restrictions. It is known that when the length of the monopole less than a quarter wavelength (λ _0/4), where λ ₀ - operating wavelength, the input resistance of the antenna becomes very small capacitive [4, 5], and therefore used to ensure a good matching of the antenna to the feeder various ways to compensate for capacitive resistance or its increase with the constancy of inductive resistance.

Next, we consider a method of changing capacitance by including an extension inductor in an asymmetric vibrator circuit. To select the appropriate nominal inductance of the extension coil, first of all, it is necessary to determine the static capacitance and wave resistance of the antenna [6].

, заряженного до потенциала U. Емкость этого проводника С есть отношение его заряда Q к потенциалу U (1).The calculation of the capacitance of an asymmetric vibrator is performed by the Howe method, which gives an error of about 5%. To do this, imagine an asymmetric vibrator in the form of a cylindrical conductor of length

charged to potential U. The capacity of this conductor C is the ratio of its charge Q to potential U (1).

The potential at different points of the conductor has the same value, however, the charge density is unevenly distributed and increases with distance from the center of the wire, especially changing sharply at its ends. Nevertheless, a relatively small change in the surface charge density on a sufficiently large part of the conductor is the basis of the Howe method, therefore, we assume that the surface charge density is unchanged at all points of the wire. Assigning an arbitrary value to this parameter, we find the potential that will have a variable value along the length of the conductor, and to eliminate the inconsistency, average the found potential value, and using formula (1), we find the antenna capacity.

To determine the potential of a long round wire from its own charge, we use the formula (2).

For a rigorous solution of the problem, it is necessary to solve the integral equation in which the surface charge density q is a function of the coordinate z, and ϕ = const, R is the distance from the influencing point to the considered one. In this case, on the contrary, we set q = const and find ϕ.

и от правого конца на (1-α)

. Тогда на элементе с бесконечно малой длиной dz на расстоянии z от начала координат возникнет элементарный потенциал dU, создаваемый зарядом этого элемента. Расстояние от начала координат до поверхности элемента определяется выражением (3):Let us take an arbitrary point 0 on the axis of the wire (Fig. 3), spaced from its left end by α

and from the right end to (1-α)

. Then, on an element with an infinitely small length dz at a distance z from the origin, the elementary potential dU arises, created by the charge of this element. The distance from the origin to the surface of the element is determined by the expression (3):

where r is the radius of the wire. The charge on the element dz is qdz (q is the charge per unit length), therefore, the elementary potential at the zero point is calculated according to (4):

до (1-α)

:We obtain the full potential at point 0 by integrating (4) along the length of the wire, i.e. from α

up to (1-α)

:

The integral function (4) can be reduced to a logarithmic function, as shown in [5]:

Graphically, the change in potential U _α along the wire is shown in FIG. 5, where the function U _{α is} normalized. As can be seen from FIG. 4, the potential varies along the wire. To obtain the average value of the potential, it is necessary to integrate function (5) over α, i.e. find the integral (6):

Given that we cover the full length of the wire at α = 1, we finally get:

Now, using expression (1), we find the capacitance of the wire:

So, for example, the capacity of a three-meter wire with a radius of 8⋅10 ^-4 m is 2.107⋅10 ^-11 Farad, and its linear capacity is 7.023⋅10 ^-12 Farad / meter, respectively.

The known value of linear capacitance makes it possible to calculate the wave impedance of the antenna ρ [6] according to the formula (8):

where c is the speed of light in vacuum, C _pog is the linear capacity of the wire.

Now, according to [6], we have all the input data for calculating the inductance of the extension coil. In FIG. 5 shows a diagram for calculating an extension coil in an asymmetric vibrator. The resonance value of the inductance is calculated by the formula (9):

where m = ω / s = 2π / λ is the wave number; ω = 2πƒ is the cyclic frequency. You can also find the current distribution in the wire, according to expressions (10):

where I _A is the amplitude of the current at the antenna input, and I ₁ and I ₂ are the currents in the upper and lower parts of the asymmetric vibrator.

The current distribution over the vibrator is graphically shown in FIG. 6, where the upper curve shows the current distribution when the extension coil is turned on, and the lower curve when it is absent. For example, the current distribution functions are calculated based on an operating wavelength of 30 m, a vibrator length of 3 m, and an extension point of an extension coil of 2.25 m from the source. At the point of inclusion of the extension coil, the derivative function of the current undergoes discontinuity, and the function itself has a shape close to trapezoidal. As can be seen from a comparison of the current distribution, the presence of an inductor gives a gain in the strength of the current flowing through the antenna, which allows to increase the antenna gain. Quantitatively, this effect can be estimated by calculating the difference in the integrals of the corresponding current functions along the length of the vibrator, which is equivalent to the difference in the areas under the curves showing the current distribution in the antenna. This is analytically described by expression (11):

As can be seen from FIG. 7, the difference in the integral functions of the current (11) increases linearly with the distance of the coil from the source. Therefore, a greater effect can be obtained by installing the inductor closer to the edge of the vibrator, however, in this case, the loss resistance increases in it, so it makes sense to choose the connection point of the coil so that the loss resistance is less than the radiation resistance.

The radiation resistance and loss resistance can be found from expressions (12) and (13), respectively.

Formula (13) makes it possible to evaluate ways to reduce the loss resistance. Firstly, it is necessary to lower the wave impedance, which is achieved by increasing the antenna capacity due to the thickening of the wire elements, namely, their implementation in the form of thick pipes or a set of wires. Secondly, it is possible to increase the quality factor of an extension coil, but in practice the quality factor above 500 is very difficult to obtain, therefore, it is proposed to use a gyrator as an inductive element, by selecting resistances in the circuit of which it is possible to achieve a quality factor of several thousand units. In FIG. Figure 8 shows that at high values of the Q factor of the inductive element, it can be located far enough from the source, thereby obtaining a significant gain in the radiation power. The gyrator circuit is shown in FIG. 13.

For this gyrator circuit, relations (14) and (15) are valid:

In addition to a positive effect on the gain, the inclusion of an additional element causes a decrease in the antenna efficiency, which also depends on the quality factor of the extending inductance. To calculate the efficiency, it is necessary to calculate the ratio of the radiation resistance to the antenna impedance, i.e. carry out calculations according to the formula (16):

Graphically, the antenna efficiency at various values of Q _L is shown in FIG. 9.

The gain in radiated power can be estimated using the simple expression (17):

where I ₁ , I ₂ are the integral functions of the currents in the vibrator arm (without turning on the inductance and with the inductance turned on, respectively), R ₁ , R ₂ are the total active resistances of the antennas.

As can be seen from the graphs in FIG. 10, the power gain at a low Q factor of the inductive element is negative for any coordinate of the point of inclusion in the arm of the vibrator, that is, we have power losses, since the increase in the loss resistance exceeds the growth in the radiation resistance. Increasing the quality factor, we get the opportunity to position the inductive element farther from the source, thereby increasing the gain of the radiated power.

Equating the derivative of function (17) with respect to the coordinate to zero, we can find the location point of the inductive element that gives the maximum gain in the radiated power, such a point for an asymmetric vibrator is a point at a height of 2.7 meters for a three-meter vibrator.

Thus, the considered embodiment of the shortened antenna with the control system of the impedance converter 15 (Fig. 11 and Fig. 12) makes it possible to increase the radiation power, as calculations show, with a high figure of merit of the inductive element included in the antenna current circuit, while the losses are minimal enough . Frequency tunable inductance can be created using a controlled gyrator or an impedance converter control system 15. Therefore, a 10-meter asymmetric vibrator can be replaced with a three-meter asymmetric vibrator by maintaining the specified current parameters, as proved by the studies performed above.

In FIG. 13, the principle of a controlled device in the form of an impedance converter (gyrator) 11 is implemented, which provides an intrinsic wavelength mode for an asymmetric vibrator by changing the inductive resistance depending on the frequency of the antenna. An impedance converter (herator) 11 is shown in FIG. 13, contains the first op-amp 1 and the second op-amp 2; operational amplifiers, resistors: the first R1, second R2, third R3 and fourth R4, load capacitance C and varicap Vp; the controlled input of the impedance converter (gyrator) 11 is connected to the positive input of the second operational amplifier OU2 through varicap Vp, the negative input of the second operational amplifier OU2 is parallelly connected to the negative input of the first operational amplifier OU1 and through the third resistor R3 with an earth wire, and through the fourth resistor R4 the negative input of the second operational amplifier OU2 is connected to the output of the first operational amplifier OU1; the first output of the impedance converter (gyrator) 11 is connected to the positive input of the OS1; the output of the first operational amplifier OU1 is connected through a second resistor R2 in parallel with the positive input of the second operational amplifier OU2, with a load capacity C and with the output of the varicap Vp; the second output of the impedance converter (gyrator) 11 is connected in parallel with the negative input of the first operational amplifier OU1; the positive input of the first operational amplifier OU1 is connected to through the first resistor R1 in parallel with the load capacitance C and to the output of the second operational amplifier OU2.

The principle of operation of the impedance converter (gyrator) is presented in the literature of the authors U. Titze, K. Schenk "Semiconductor circuitry" - M .: ed. Mir, 1983, section 12.6, pp. 180-183.

The impedance converter (gyrator) 11 (Fig. 13) allows you to convert the reactance of the load capacitance C into inductive resistance at the symmetric output 1-2 of the impedance converter (gyrator) 11, and this resistance depends on the voltage supplied through the input of the converter 11 (Fig. 13). 13), through the varicap VP to the positive input of the second operational amplifier OU2. Load capacity With the action of the varying capacitance of the varicap Vp, when the applied voltage changes on it, it changes the value of the load capacity at the input of OS2. And, therefore, the magnitude of the inductive resistance at the outputs of one or two 1-2 impedance converters 11. Thus, the inductive resistance of the impedance converter (gyrator) 11 is adjusted (Fig. 13). In this case, the positive input of the first operational amplifier is connected in parallel with the first output, and through the first resistor with the output of the second operational amplifier and through the load capacitance with the positive input of the second operational amplifier; the positive input of the second operational amplifier is connected in parallel through the second resistor to the output of the first operational amplifier, and through a varicap with the input of the gyrator; the output of the first operational amplifier is connected through a fourth resistor to the negative input of the first operational amplifier; the negative input of the first operational amplifier is connected in parallel with the second output of the gyrator, also with the negative input of the second operational amplifier, and through the third resistor with an earth wire.

, зная емкость С у гиратора (фиг. 13) можно определить индуктивность, исходя из параметров гиратораA reactance converter or a gyrator allows you to convert the load capacitance C (Fig. 13) into an inductance at the output of one or two 1-2 gyrators, ensuring the tuning of the input inductive resistance of the antenna, in other words, to extend or shorten the length of the antenna, tuning the antenna in resonance with the generator frequency . It is quite difficult to create such an inductance, since it will have a large weight and very significant dimensions of the inductance elements L and capacitance C. The necessary inductance L _{0 of the} parallel oscillatory circuit is calculated to receive the operating frequency range of the electromagnetic field radio reception in accordance with the formula

knowing the capacitance C at the gyrator (Fig. 13), it is possible to determine the inductance based on the parameters of the gyrator

L ₀ = (R1⋅R2⋅R4⋅C) / R3, where L ₀ - in H, R - in Ohms, C - in nanoFarads.

In parallel to the capacitance C, a Vic varicap is included, which allows you to change the load capacitance depending on the applied voltage to the varicap up to 300 pF, if necessary, increase the capacitance should include a varicap block instead of one. The work of the varicap is presented on page 24, section 3.3, in the literature of the authors W. Titze, K. Schenk "Semiconductor circuitry" - M .: ed. Mir, 1983. The principle of controlling the change in inductance at the output of the gyrator is shown in the journal Radio 11, for 1996, by the author Petin G.P. "The use of a gyrator in resonant amplifiers and generators." The control of the gyrator is shown in FIG. 12 and is carried out by the frequency voltage of the generator U _A (transmitting device 1) exciting the antenna. The voltage of the generator is supplied to the input of the down-converter 9 (Fig. 12). Frequency reduction is necessary for the stable operation of reactance converters, their operation is critical to the phase difference of the operational amplifiers ОУ1 and ОУ2 (Fig. 13). Lowering the frequency does not affect their operation, since after the frequency reduction converter 9, a frequency-voltage converter 10 is installed.

Design and principle of operation of a shortened asymmetric vibrator.

и верхнего излучающего элемента 3 длиной

, имеет общую длину двух излучающих элементов вибратора

метра, общая длина излучающих элементов несимметричного вибратора разделена на высоте 2,7 метра изолятором 2 длиной

, точки разделения излучающих элементов 1 и 3 несимметричного вибратора изолятором 2 соединены через систему управления преобразования импедансов 15; система управления преобразования импедансов 15 содержит гиратор 11, преобразователь понижения частоты 9, преобразователь частота-напряжение 10 (фиг. 12 и фиг. 13).The asymmetric vibrator (Fig. 11) consists of two parts: the lower radiating element 1 of length

and upper radiating element 3 long

has the total length of the two radiating elements of the vibrator

meters, the total length of the radiating elements of the asymmetric vibrator is divided at a height of 2.7 meters by an insulator 2 of length

, the separation points of the radiating elements 1 and 3 of the asymmetric vibrator by the insulator 2 are connected through an impedance conversion control system 15; the impedance conversion control system 15 comprises a gyrator 11, a frequency down converter 9, a frequency-voltage converter 10 (FIG. 12 and FIG. 13).

In FIG. 11 shows a design model of a shortened asymmetric vibrator for use on ships. The high-frequency voltage generator 4 provides the specified mode of operation of the power amplifier 5. The power amplifier and the generator are located inside the hull 14. The antenna, an unbalanced vibrator, is connected to the output of the power amplifier 5 by a coaxial cable 6 through a cable channel in the hull 14. The asymmetric vibrator is located on the insulator 7 located in the antenna housing 12. The antenna housing 12 is bolted 13 to the hull of the vessel 14. The coaxial cable 6 of the central core is connected in parallel from point “a” to using the lower radiating element of the asymmetric vibrator 1 at points KK and with the input of the frequency reduction converter 9. The screen sheath of the coaxial cable 6 is connected to the hull of the vessel 14. The output of the frequency reduction converter 9 is connected to the gyrator 11 through the frequency-voltage converter 10. The first output of the gyrator 11 is connected at point N to the base of the upper radiating element 3 of the asymmetric vibrator at a height of 2.7 meters relative to the lower radiating element, and the second output of the gyrator 11 is connected at point M in the upper part of the lower a radiating element monopole 1.

=λ₀; ƒ₀=С/λ₀ называется режимом собственной длины волны антенны). Режим работы обеспечивает заданное условие для частоты генератора 4 - ƒ₁. Учитывая, что гиратор 11 обеспечивает подключение к точкам М и N, заданную величину индуктивного сопротивления без потерь, образованный колебательный контур антенной и выходом гиратора имеет высокую добротность и, следовательно, антенна имеет значительные токи, чем достигается высокий КПД. При перестройке генератора 4 на частоту ƒ₂, не равную ƒ₁, происходит изменение индуктивного сопротивления между точками М и N за счет работы системы управления преобразования импедансов 15.The voltage of a given frequency ƒ _{1 of the} high-frequency generator 4 is supplied to the input of the power amplifier 5, the latter provides the required gain to maintain the required power at the input of the asymmetric vibrator, consisting of two conductive parts: the lower radiating element 1 and the upper radiating element 3, and insulation 2 between them. In fact, an asymmetric vibrator consists of three parts: a lower radiating element 1, 2.7 meters long, made in the form of a metal cylinder, inside of which there is an impedance conversion control system 15, which contains: a gyrator 11, a frequency-voltage converter 10 and a frequency reduction converter 9 ; the middle part of the antenna of the asymmetric vibrator - insulator 2 and the upper radiating element of the asymmetric vibrator 3 in the form of an all-metal rod 30 cm long. From the output of the power amplifier 5, a voltage of frequency ƒ _{1 is} supplied through a coaxial cable 6, connected by the central core through point “a” to the base of the asymmetric vibrator to the points KK, in its lower part of the lower radiating element of a cylindrical shape. In parallel, the central core of the coaxial cable is connected to point “a” with the input of the frequency reduction converter 9. Applied voltage to the cylindrical base of the lower radiating element 1 of the antenna leads to the appearance of current in the cylindrical part of the antenna. At the same time, the applied voltage with a frequency of ƒ ₁ through the impedance conversion control system 15 (Fig. 12) provides the connection of points M and N through the inductive resistance necessary to ensure the antenna’s own length mode (It was previously indicated that the mode of operation with parameters 4 с

= λ ₀ ; ƒ ₀ = C / λ ₀ is called the mode of the natural wavelength of the antenna). The operation mode provides the specified condition for the frequency of the generator 4 - ƒ ₁ . Considering that the gyrator 11 provides connection to points M and N, the specified value of the inductive resistance without losses, the oscillatory circuit formed by the antenna and the output of the gyrator has a high Q factor and, therefore, the antenna has significant currents, which ensures high efficiency. When the generator 4 is tuned to a frequency ƒ ₂ not equal to ƒ ₁ , the inductive resistance between the points M and N changes due to the operation of the impedance conversion control system 15.

The set of essential features of the claimed device will ensure the achievement of the goal. The authors are not aware of technical solutions from the field of radio communications, antenna technology, containing signs equivalent to the hallmarks of the claimed device. The authors are not aware of technical solutions from other areas of technology that have the properties of the claimed technical solution. Thus, the claimed technical solution, according to the authors, has the criterion of essential features.

Bibliography

1. Goncharenko I.V. Antennas KB and VHF. Part II Basics and practice. - M .: IP RadioSoft, 2005 .-- 288 p.

2. Schelkunoff S.A., Friis N.T. Antennas - New York: John Wiley & Sons, Inc., 1952.603 c.

3. Balanis C.A. Modern antenna handbook, New York: John Wiley & Sons, Inc., 2008 1680 c.

4. Eisenberg G.Z. Shortwave antennas. - M .: Svyazizdat, 1962 .-- 562 p.

5. Pistolkors A.A. Antennas - M .: Svyazizdat, 1947 .-- 479 p.

6. Muravyov Yu.K. Handbook for calculating wire antennas. - L .: YOU, 1978. 392 p.

Claims (4)

1. A shortened asymmetric vibrator containing a high-frequency generator connected via a power amplifier with a coaxial cable line to a vertical radiating element of an asymmetric vibrator, which is mounted on an insulator with a fixed metal antenna body and a ship's hull (3 zap), characterized in that an asymmetric vibrator is added, consisting of of two components, the lower radiating element and the upper radiating element, isolated from each other, with a total total length of three ra l = 3, the lower radiating element length l1 = 2,7 m is conducting and cylindrical in shape, hollow inside structurally in a cylinder cavity located impedance conversion control system comprising a gyrator converters and reducing the frequency and frequency-to-voltage and allows through the use of transducers lowering the frequency of the generator and the frequency-voltage to perform the tuning of the gyrator, its directly inductive resistance. included in the input resistance of the antenna, and change the resistance value to the value required to maintain a constant current in the antenna at any frequency of the operating range and, as a consequence, the constancy of its efficiency, based on lengthening or shortening the length of the antenna, tuning the antenna in resonance with the frequency of the generator; the upper radiating element of the asymmetric vibrator is represented by an all-metal rod of length l3 = 0.3 meters, fixed with its base through a flat high-resistance resistance R on the upper part of the lower radiating element of the asymmetric vibrator; wherein the high-frequency oscillation generator is connected through a power amplifier using the central core of the coaxial cable line to the base of the lower radiating element, the cylindrical part of the vertical asymmetric vibrator to its KK points, and in parallel to the input of the impedance conversion control system; the first output of the impedance conversion control system is connected directly at point N to the base of the upper radiating element of the asymmetric vibrator, and the second output of the impedance conversion control system is connected at point M to the upper part of the lower radiating element of a cylindrical vertical asymmetric vibrator. 2. The shortened asymmetric vibrator according to claim 1, characterized in that the impedance conversion control system comprises a gyrator, a frequency-voltage converter and a frequency converter, while the input of the impedance conversion control system is connected to the input of the frequency converter, and the output of the frequency converter through frequency converter the voltage is connected to the input of the gyrator, the first output of the gyrator is connected to the first output of the impedance conversion control system, and the second output of the gyrator is connected to the second output of the impedance conversion control system. 3. The shortened asymmetric vibrator according to claim 2, characterized in that the gyrator comprises first and second operational amplifiers; the first, second, third and fourth resistors, load capacitance and varicap, while the positive input of the first operational amplifier is connected in parallel with the first output of the gyrator, and through the first resistor with the output of the second operational amplifier and through the load capacitance with the positive input of the second operational amplifier; the positive input of the second operational amplifier is connected in parallel through the second resistor to the output of the first operational amplifier, and through a varicap with the input of the gyrator; the output of the first operational amplifier is connected through a fourth resistor to the negative input of the first operational amplifier; the negative input of the first operational amplifier is connected in parallel with the second output of the gyrator, also with the negative input of the second operational amplifier, and through the third resistor with an earth wire.

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