RU2743624C1 - Dipole end antenna - Google Patents

Abstract

FIELD: antenna tech.SUBSTANCE: invention relates in particular to end-face dipole antennas operating in the microwave range. The technical result is achieved by the fact that in the end antenna of a dipole type, containing a cylindrical metal bowl with a flat bottom, a thin lateral cylindrical wall and an open end, located outside the bowl parallel to the plane of the end near it, a radiator consisting of two identical elongated collinear thin cylindrical solid radiating conductors, the length of which does not exceed the radius of the bowl, a pair of identical coaxial lines orthogonal to the bottom, the length of which exceeds the depth of the bowl, consisting of tubular outer and solid inner conductors, while the deep ends of the outer conductors of the segments are galvanically connected to a flat bottom, the deep ends of the inner conductors of the segments pass through the bottom of the bowl through round holes in it, the diameter of which is equal to the inner diameter of the tubular outer conductors, in contrast to the prototype, a section of a circular waveguide operating on the dominant TE11 wave is additionally introduced, the diameter of which is smaller than the diameter of the bowl, and two identical coaxial open ring conductors, the diameter of which does not exceed the radius of the circular waveguide, while the outer side of the bottom of the bowl is galvanically connected to one of the ends of the circular waveguide so that the axis of the bowl does not coincide with the axis of the circular waveguide, the segments of identical coaxial lines are spaced apart relative to the axis of the waveguide in opposite directions along a line passing through the axis of the waveguide parallel to the transverse component of the magnetic field strength of the dominant TE11 wave passing inside the waveguide near the bottom of the bowl, the deep ends of the inner solid conductors of the aforementioned segments, passing inside the circular waveguide through holes in the bottom of the bowl, are galvanically connected to the ends of the same name of open circular conductors, the common axis of which is parallel to the separation line of the segments of coaxial lines and is spaced inside the waveguide from the outer side of the bottom of the bowl at a distance equal to 1.25 of their radius, the deep ends of cylindrical collinear radiating conductors are galvanically connected to the outer ends of the inner solid conductors of the mentioned sections of coaxial lines, while the length of the radiating conductors is 0.9 of distance between the axes of the spaced sections of coaxial lines, the outer ends of the outer tubular conductors of which are open, and the second end of the circular waveguide is the input / output of the antenna.EFFECT: technical result of the invention is the formation of a radiation pattern with the same width of the main lobe in the E- and H-planes, directed along the axis of the supply waveguide in the direction of the surrounding free space in front of it.1 cl, 8 dwg

Description

The proposed end-face dipole antenna (TADV) belongs to the field of antenna technology in the microwave range and, being powered by a circular waveguide, is designed to form linearly polarized radiation with a directional pattern having equal angular width at the half power level both in E- and and in the H-plane.

The urgency of improving this type of antennas is due to the ever-increasing requirements for antenna systems of the centimeter range in relation to their overall and mass indicators, as well as the need to simplify layout, assembly and adjustment work with highly reliable installation of antennas on mobile installation objects, including the board of a manned small aircraft or drone, car body or tractor, etc. At the same time, the requirement for an all-round simplification of the antenna design and the maximum increase in its production and operational manufacturability when powered by standard waveguides, which have very small dissipative losses in the centimeter wavelength range, compared to coaxial, strip and microstrip transmission lines, is very important.

Known TADV, described in the work: G.T. Markov, D.M. Sazonov, "Antenna", M .: "Energy", 1975, p. 445, fig. 13-24. In this antenna, which serves as a parabolic reflector feed, the vibrator radiators are powered by the end (in other words, aperture) of a rectangular waveguide. The vibrators are fixed on a metal plate soldered parallel to the wide wall into the opening of the waveguide in the middle of it. The plate, being perpendicular to the transverse component of the electric field strength of the dominant TE10 wave in the aperture of the waveguide, does not participate in radiation, since it is formed only by vibrators. At the same time, it is possible to equalize the width of the main lobe of the radiation pattern in the E- and H-planes only with four vibrators fixed on the plate.

However, the practical implementation of such a TADV is associated with structural and technological difficulties associated with the cantilever mounting of the plate to the end of the waveguide and with a noticeable number of vibrators (there are four of them). In addition, the main lobe of the radiation pattern is oriented along the waveguide axis not to the surrounding free space in front of it, but to the opposite side, in other words, towards the waveguide itself. This leads to the dissipation of a part of the energy of the emitted signal due to dissipative losses in the outer surfaces of the metal walls of the supply waveguide going from the depth of the mirror to the TADV that irradiates it. Dissipative losses increase in proportion to the square root of the frequency, so that in the centimeter wavelength range, their level may become unacceptable.

In addition, the described TADV is poorly adapted for independent use (that is, without a mirror reflector) as part of the homing system equipment located in the nose of the projectile head or rocket, since the transmit-receive units are mounted inside the rocket behind the nose. Therefore, the radiation of such a TADV will be directed towards the feeding waveguide coming from the depth of the rocket, that is, in the direction opposite to the flight of the rocket.

Thus, the TADV described in the work of G.T. Markov, D.M. Sazonov "Antenna", is characterized by the formation of the main lobe of the radiation pattern with the same angular width in the E- and H-plane, low manufacturability and the impossibility of radiation along the axis of the supply waveguide in the direction of the surrounding free space in front of it.

Also known TADB, described in US patent No. 4109254, H 01 Q 21/26, published 08/22/1978, entitled "Dipole radiators for feeding a parabolic reflector". This antenna serves as a parabolic reflector feed and contains a half-wave dipole radiator surrounded by the walls of a cylindrical resonator without an upper round cover (see Fig. 1 and Fig. 2 for its description). As a result, a cylindrical bowl is formed, at the bottom of which a coaxial-slot balancing device is mounted inside it, powered by a coaxial cable passing through the hole at the bottom of the bowl and going to the outside of it. The diameter of the bowl is approximately three times its depth.

, где

- длина волны излучаемого гармонического сигнала. Сама чаша имеет диаметр

и глубину

, так что диполь расположен в плоскости верхнего отверстия (другими словами, торца) чаши. In the case of linear polarization, the half-wave dipole rises above the bottom of the bowl to a height

where

is the wavelength of the emitted harmonic signal. The bowl itself has a diameter

and depth

, so that the dipole is located in the plane of the upper hole (in other words, the end face) of the bowl.

In the case of circular polarization, two crossed, orthogonal to each other, half-wave dipoles are used, powered from the bottom of the bowl by two combined coaxial-slot baluns in phase quadrature (see Figures 5 and 6 of the Description of the mentioned patent), thereby forming a turnstile antenna inside the bowl. Despite the fact that the described antenna, both with linear and circular polarization, forms a radiation pattern with approximately the same angles at the half-power level in the main planes of the section, its power supply is carried out by a coaxial cable fixed outside the bowl. The adaptation of such a power supply to the end of a standard waveguide is associated with significant structural, layout and technological difficulties due to the need to implement narrow longitudinal slots in the centimeter range in the coaxial-slot balancing device and fix this device to the bottom of the bowl, which, in turn, must be attached to the end of the waveguide. Indeed, the length of half-wave dipoles at the lower frequency boundary of the centimeter range (i.e., wavelength 10 cm, frequency 3 GHz) is 50 mm, and the length of the outer conducting cylinder of the coaxial-slot balun should be on the order of a quarter of the operating wavelength, that is , about 25 mm (see the aforementioned work of G. T. Markov, D. M. Sazonov "Antenna", p. 340, Fig. 9-4). It is in the walls of this cylinder that two quarter-wave slots, 25 mm long and about 1 mm wide, located opposite each other, open at the upper end of the cylinder, must first be milled. These milled metal cylinders must be galvanically (e.g. by soldering) connected to the inner surface of the bottom of the bowl, and then the inner cylindrical conductors of the coaxial-slot balun, which extend outside the bowl from the side of its bottom, must be passed through and properly secured with dielectric bushings. through pre-drilled holes in it. On the outside of the bowl, both of these conductors are properly connected via a microwave power divider in half with a single coaxial feed cable.

Thus, the TADV described in US Pat. No. 4,109,254 is poorly adapted to generate radiation along the axis of the feed waveguide towards the surrounding free space in front of it.

Also known TADV, described in US patent No. 4668956, H 01 Q 1/36, published 05/26/1987, entitled “Broadband cup antennas”. This antenna contains both one half-wave dipole (for the formation of linearly polarized radiation), and two of the same dipoles, located perpendicular to each other (for the formation of circular polarization of the radiation). Both the dipole and their pair lie in a plane parallel to the bottom of the cylindrical metal bowl. This plane is removed from the bottom at a distance equal to practically the depth of the bowl, so that the dipole emitters are located almost in the opening of the bowl. In this case, the antenna contains additional reflective elements located between the radiating dipoles and the bottom of the bowl, properly connected to the coaxial nodes of the antenna power system. Both emitting dipoles and reflective elements are made of mesh from thin conductors. This is evidenced by figures 1, 3, 7 and 9, as well as lines 66-68 column 2 and lines 1-12 column 3 of the patent description: “A pair of parasitic elements 32 and 34, made of a similar conductive wire mesh as the monopoles , are positioned below the monopoles and closely adjacent thereto. The elements 32 and 34 are also formed in a substantially short spiral pattern, and serve as capacitor elements providing an inverse reactance which is added to the reactance of the monopoles to achieve broadband operation. The parasitic elements 32 and 34 are connected to a conductive ring 38 which is disposed about the outer conductors of coaxial line 17. The conductive ring is electrically and physically connected to the inner ends of the conductive parasitic elements. An insulating material 40, such as Teflon, is disposed between the conductive ring 36 and the parallel legs 18a and 18b of the conductive coaxial line 17 ”.

As a result, such an antenna forms a directional pattern, the main lobe of which is directed along the axis of the bowl and has almost the same angular width in the E- and H-planes, which during the microwave period either retain their orientation in space (with linear polarization), or perform one rotation around the direction of propagation along the axis of the bowl (with circular polarization). In this case, the role of a balun is played by a very cumbersome set of coaxial nodes, including a quadrature directional coupler 70 (in the original: quadrature hybrid coupler 70, - item number 70 is indicated in accordance with the description of the patent) and reflective mesh elements mounted in the depth of the bowl between the emitters and its bottom according to the Formula of the patent. This is evidenced by lines 17-46 of column 4 of its description: “As illustrated in Fig. 8, an additional feed line 72 is supplied for the coaxial line55 constituting the coaxial outer conductors 56a and 56b and inner conductor 58, which are spaced at 90-degree intervals from the conductors of coaxial line 17. The monopoles are connected through conductive elements 44 , 46, and 74, 76. A shorting element (not shown) similar to the shorting element 26 shown in Fig. 2 is also provided for the coaxial line 55. The two dipoles are connected to a utilization apparatus through an input coaxial line via a quadrature hybrid coupler 70 having two output lines 71 and 73 connected to the feed lines 42 and 72. A decoupling input port 68 is connected either to a matched termination or second utilization apparatus. The cup turnstile antenna affords a controllable uniform circularly polarized radiation patterns. By virtue of this invention, a cup dipole antenna and cup turnstile antenna are constructed without the need for impedance transformers for splitting coaxial lines to provide a balanced output from an unbalanced input. The balancing occurs within the antenna cup as a result of the novel assembly. The radiation patterns obtained with the antennas disclosed herein are relatively uniform and controllable. The configuration of the cup turnstile antenna also minimizes the cross-coupling effect between the coaxial lines. The short spiral type design of the monopoles effectively expands the bandwidth of the cup dipole antennas, and the parasitic elements substantially improve the bandwidth ”.

However, despite the large bandwidth of such an antenna compared to the antenna according to the previously mentioned US patent No. 4109254, its power is still carried out from the coaxial cable going to the antenna from the bottom of the bottom of the bowl (see Figures 3, 7 and 8, as well as the corresponding lines the description of US patent No. 4668956). Therefore, the adaptation of such a power supply to the end of a standard centimeter waveguide seems to be very problematic.

Thus, this TADV is poorly adapted for the formation of radiation along the axis of the supply waveguide in the direction of the surrounding free space in front of it.

Also known TADB, described in US patent No. 5748156, H 01 Q 3/00, published 05/05/1998, entitled “High-performance antenna structure”. This antenna contains a dipole emitter located in the opening of the metal bowl parallel to it and powered by a system of coaxial metal and dielectric cylindrical fragments forming a rotating coaxial joint. The rotation of the dipole emitter is carried out by means of this articulation by an executive electric motor, the axis of which coincides with the axis of the bowl. The antenna also contains a printed circuit board located inside the bowl, on which is mounted a preamplifier based on lumped elements, the output of which, in transmission mode, properly feeds the dipole emitter through a conductor system implemented according to the Formulas of this patent. This is evidenced by figures 1, 2, 3 and lines 57-67 column 5, as well as lines 1-6 column 6 of the patent description: “In the preferred embodiment, C3 is a cylindrical sleeve of predetermined length, preferably substantially one quarter wavelength at the frequency of interest, and it terminates at an air gap 50 defined between its free end 51 and the back of the plate defining the back wall 18 of the cup 16. The conductor sleeve C2 which also has a preferred length of substantially one quarter wavelength at the frequency of interest terminates short of the plate 44 defining a second air gap 52. As shown in Fig. 2, C2 is the inner conductor for the outer conductor C3 in the assembled unit and together with C3 defines a coaxial transmission line for signals fed to the dipole array from the processing circuitry formed on the printed circuit board 40. At the same time, C2 is the outer conductor for the inner conductor C1. Considered together, C1, C2 and C3 define a rotary joint defined by a coaxial unbalanced transmission line for feeding the dipole array ”. In this case, the amplifier input is connected to a standard coaxial connector mounted on the side outside the bowl on an auxiliary pedestal (see Fig. 1 of the patent description). It is clear that if the preamplifier is operating in the receive mode, then the amplifier output is connected to the said coaxial connector, and its input is powered by a signal taken from the dipole terminals through the conductor system of the aforementioned rotating joint.

As a result, the antenna generates axial linearly polarized radiation, the polarization plane of which can have an arbitrary orientation in space, depending on the position of the motor shaft. In this case, the width of the main axial lobe of the radiation pattern has practically the same angular width at the half-power level in the E- and H-planes orthogonal to each other. And although the patent mentions the possibility of using waveguides (see lines 51-56 of column 4 of the description) and the possibility of using this antenna for receiving radio transmissions from satellites in geostationary orbit (see lines 26-29 of column 5 of the description), some detail information revealing the features of the claimed prospects when using waveguides in the centimeter range is not provided in the mentioned patent.

As a result, figure 1 of the description of this patent does not make it possible to form an unambiguous idea of how to power this antenna in the centimeter wavelength range with the end of the waveguide, along the axis of which the drive of an external electric motor to the rotating dipole connection must be realized so as not to disturb the structure of the dominant electromagnetic field. waveguide waves. For any violation of the structure of the field inside the waveguide inevitably leads to a noticeable mismatch and, as a result, to an increase in its input reflection coefficient (in other terminology: its input standing wave ratio) to unacceptable values.

Thus, this TADV is also poorly adapted for the formation of radiation with a maximum radiation pattern on the axis of the supply waveguide in the direction of the surrounding free space in front of it.

The prototype of the present invention is advantageously different from the previously mentioned TADV in its structural and layout unambiguity and very acceptable manufacturability of the end antenna described in US patent No. 3740754, H 01 Q 21/26, published 06/19/1973 under the name “Broadband cup-dipole and cup- turnstile antennas ”. The description of the principle of operation of this antenna, mounted in the depth of the metal bowl, includes provisions that characterize and concretize the set of features claimed in this patent, mainly from the point of view of the formation of electromagnetic radiation into the surrounding free space. All other factors, including the implementation of baluns and microwave coaxial bridges required for the implementation of a turnstile antenna, are not specified in the description of this patent, since it is believed that they were implemented by the classical techniques of that time (early 70s) outside the antenna and connected to a pair or four coaxial cables (see Figures 1 and 7 for the description).

The antenna itself contains a cylindrical metal bowl with a flat bottom, near the open end of which either one dipole emitter or a crossed turnstile consisting of two identical dipoles are located parallel to it. The latter are fixed on rigid metal fixing elements made of tubular and solid cylindrical blanks, properly connected to each other according to the formula of the aforementioned patent. In these connections, dielectric inserts, bushings, fillings and gaps are provided, forming together with metal tubes and cylinders (both tubes and cylinders are preliminarily formed mechanically) a fairly compact system built into the bowl, which, being connected to external (serially produced at that time in the USA) by nodes via coaxial cables, excites the dipole emitters so that the antenna forms radiation, the maximum of the radiation pattern of which lies on the axis of the bowl. This is evidenced by Figures 1, 2, 3 and 4, as well as lines 13-30 of column 2 of the description of this patent: “In accordance with this invention, monopole elements 15a and 15b are energized by coaxial feed lines 21 and 22, respectively, which are connected through a lumped-circuit impedance transformer 24 to an external standard coaxial input line 25 linking the antenna assembly to utilization apparatus R such as a receiver. Impedance transformer 24 is of the type having a pair of anti-phase outputs and is a commercially available component; this transformer serves to excite monopole elements 15a and 15b in the manner of a center-fed dipole and also transforms the average inherent impedance of the antenna from its relatively high value to the value of the characteristic impedance of coaxial input line 25. For example, the average antenna impedance may be approximately 150 ohms and that of the coaxial input line 25 may be 50 ohms. In this case, for the reason described hereafter, the characteristic impedance of each of coaxial lines 21 and 22 is preferably 75 ohms ”. In this case, the angular width of the main lobe of the radiation pattern in the E- and H-planes is approximately the same (see lines 7-9, column 1 of the description: “The cup-dipole antenna is well known in the art for its equality of radiation patterns in the electric ( E) and magnetic (H) planes ”).

However, the described antenna is powered by coaxial cables and external peripheral microwave devices that were commercially available at the time, such as an impedance transformer 24 (line 19 of column 2 of the description) and a 3 dB quadrature directional coupler 41 (line 48 of column 4 of the description). At the same time, each of the peripheral devices has several (from two for a transformer to four for a coupler) coaxial sockets, and the cables themselves end with cable plugs for reliable electrical connection to sockets. And if in the low-frequency part of the decimeter range you can still put up with the dissipative losses inherent in these nodes, then already in the centimeter range, when the dissipative losses increase in proportion to the square root of the frequency, the level of these losses becomes unacceptable. In addition, inhomogeneities in the junction zones of the coaxial plug-socket pairs in the centimeter range begin to play an increasingly negative role, as the dimensions / dimensions of the coaxial pairs decrease, and the dimensional tolerances and requirements for the roughness of the inner surfaces of these pairs increase. The latter is determined by the quality of metalworking machines / centers of enterprises that serially produce peripheral units for widespread use in equipment for various purposes, which can lead to an unacceptable cost of TADV production according to the mentioned prototype patent.

Thus, this TADV is practically not adapted to form radiation in the centimeter range along the axis of the supply waveguide in the direction of the surrounding free space in front of it.

The objective (technical result) of the present invention is to create in the centimeter wavelength range an end antenna of a dipole type with the same width of the main lobe of the radiation pattern in the E- and H-planes, directed along the axis of the supply waveguide in the direction of the surrounding free space in front of it.

The solution to the problem is provided by the fact that a known end-face antenna of a dipole type, containing a cylindrical metal bowl with a flat bottom, a thin lateral cylindrical wall and an open end, is located outside the bowl parallel to the plane of the end near it, a radiator consisting of two identical elongated collinear thin cylindrical solid radiating conductors, the length of which does not exceed the radius of the bowl, a pair of identical coaxial lines orthogonal to the bottom, the length of which exceeds the depth of the bowl, consisting of tubular outer and solid inner conductors, while the deep ends of the outer conductors of the segments are galvanically connected to a flat bottom, the deep ends of the inner conductors of the segments pass through the bottom of the bowl through round holes in it, the diameter of which is equal to the inner diameter of the outer tubular conductors; in addition, a section of a circular waveguide operating on the dominant TE11 wave is introduced, the diameter of which is less than the diameter bowl, and two identical coaxial open circular conductors, the diameter of which does not exceed the radius of the circular waveguide, while the outer side of the bottom of the bowl is galvanically connected to one of the ends of the circular waveguide so that the bowl axis does not coincide with the axis of the circular waveguide, segments of identical coaxial lines are spaced apart relative to the axes of the waveguide in opposite directions along a line passing through the axis of the waveguide parallel to the transverse component of the magnetic field strength of the dominant TE11 wave passing inside the waveguide near the bottom of the bowl, the deep ends of the internal solid conductors of the aforementioned segments, passing inside the circular waveguide through holes in the bottom of the bowl, are galvanically connected to the same ends of open circular conductors, the common axis of which is parallel to the separation line of the segments of coaxial lines and is spaced inside the waveguide from the outer side of the bottom of the bowl at a distance equal to 1.25 of their radius, the same ends of cylindrical collinear radiating lines The conductors are galvanically connected to the outer ends of the inner solid conductors of the mentioned sections of coaxial lines, while the length of the radiating conductors is 0.9 distance between the axes of the spaced sections of coaxial lines, the outer ends of the outer tubular conductors of which are open, and the second end of the circular waveguide is the input / output of the antenna.

FIG. 1 shows the proposed TADV, which shows the location of the main elements both inside and in the opening of the bowl; in fig. 2 shows a sketch of the proposed TADV with a partially removed bottom of the bowl and its completely removed lateral cylindrical wall, reflecting the internal structure and connections of conducting antenna fragments, moreover, the outer surface of the bottom of the bowl, oriented towards the inside of the waveguide, is colored dark gray, and the inner surface of the waveguide itself is light - in gray; in fig. 3 shows (without observing the scale, but maintaining the proportions of the fragments) an open circular conductor, the deep ends of the tubular outer and solid inner conductors of the coaxial line segment, as well as the sections of the closed magnetic field lines of the dominant TE11 wave of a circular waveguide; in fig. 4 shows a sketch of a possible version of the TADV in the head of the homing system; in fig. 5 shows a longitudinal section of the TADV with a plane passing through the axis of one of the coaxial line segments; in fig. 6 shows a longitudinal section of a TADB with a plane passing through the axes of both segments of the coaxial line; in fig. 7 shows the frequency response of the input standing wave ratio of the TADV; in fig. 8 shows the directional diagrams of TADV.

которых не превышает радиус

чаши. При этом плоскость открытого торца параллельна плоскости

, ось

которой совпадает с осью коллинеарных излучающих проводников 4 и 5, а само начало соответствующей декартовой системы координат (

) лежит посредине между смежными концами этих проводников. Внутри чаши 1 расположена пара ортогональных дну 2 отрезков идентичных коаксиальных линий 6 и 7, длина которых

превышает глубину

чаши 1 (фиг. 1). Каждый из отрезков 6 и 7 состоит из трубчатых наружных 8, 9 и сплошных внутренних 10, 11 проводников соответственно (фиг. 2). В состав ТАДВ входит также отрезок 12 работающего на доминантной волне ТЕ11 круглого волновода, диаметр

которого меньше диаметра

чаши. При этом ось волновода

не совпадает с осью

декартовой системы координат (

), хотя проходит через ось

и отстоит от начала координат

на расстояние

(фиг. 1, фиг. 2). При этом целесообразно подчеркнуть, что на фиг. 1 для лучшей наглядности ось

декартовой системы координат, уходящая через дно 2 вглубь волновода 12, изображена внутри него штриховой линией, а ось

самого волновода 12 изображена внутри него штрих-пунктирной линией. В самой же чаше 1 и вне её открытого торца обе оси изображены сплошными линиями (фиг. 1). The proposed TADV (Fig. 1) contains a cylindrical metal bowl 1 with a flat thin bottom 2, a thin lateral cylindrical wall 3 and an open end. Outside the bowl, parallel to the plane of the end face, a radiator is located near it, consisting of two identical elongated collinear thin cylindrical solid radiating conductors 4 and 5, length

which does not exceed the radius

bowls. In this case, the plane of the open end is parallel to the plane

, axis

which coincides with the axis of collinear radiating conductors 4 and 5, and the very origin of the corresponding Cartesian coordinate system (

) lies in the middle between the adjacent ends of these conductors. Inside the bowl 1 there is a pair of segments of identical coaxial lines 6 and 7 orthogonal to the bottom 2, the length of which is

exceeds depth

bowl 1 (Fig. 1). Each of the segments 6 and 7 consists of tubular outer 8, 9 and solid inner 10, 11 conductors, respectively (Fig. 2). The TADV also includes a section 12 of a circular waveguide operating on the dominant TE11 wave, diameter

which is less than the diameter

bowls. In this case, the axis of the waveguide

not aligned with axis

Cartesian coordinate system (

), although passes through the axis

and is away from the origin

at a distance

(fig. 1, fig. 2). It is useful to emphasize here that in FIG. 1 axis for better clarity

the Cartesian coordinate system extending through the bottom 2 into the depth of the waveguide 12 is shown inside it by a dashed line, and the axis

the waveguide 12 itself is depicted inside it by a dash-dotted line. In the very same bowl 1 and outside its open end, both axes are shown by solid lines (Fig. 1).

которых параллельна оси

декартовой системы координат и расположена под ней внутри волновода на расстоянии

от плоского тонкого дна 2 чаши 1 (фиг. 2; здесь условно не показаны боковая стенка 3 полностью и дно 2 частично, - оно изображено лишь в пределах торца волновода 12). Сами идентичные разомкнутые кольцевые проводники 13 и 14 выполнены из провода, радиус которого равен радиусу сплошных внутренних проводников 10 и 11 отрезков идентичных коаксиальных линий 6 и 7 (фиг. 2, фиг. 3). При этом на фиг. 3 (с соблюдением пропорций, но не в масштабе) изображено продольное сечение предлагаемой ТАДВ плоскостью, проходящей через ось внутреннего проводника 10 отрезка коаксиальной линии 6 перпендикулярно обеим параллельным осям, находящимся друг под другом: как оси

, так и оси

, причём в позиции 15 (небольшим маркером в кружочке) показана проекция общей оси

соосных разомкнутых кольцевых проводников 13 и 14, направленной к читателю из плоскости чертежа (то есть, «к нам»). В то же время, большими маркерами без кружочков в позициях 16 обозначены направления проходящих внутри волновода 12 в области дна 2 поперечных составляющих магнитного поля доминантной волны ТЕ11, ориентированных из плоскости чертежа также «к нам». В результате отрезки 6, 7 идентичных коаксиальных линий (отрезок 7, параллельный отрезку 6, на фиг. 3 не показан, так как он не попадает в плоскость упомянутого продольного сечения) разнесены относительно оси

круглого волновода 12 в противоположные стороны (фиг. 1) вдоль линии «а»-«а», проходящей через ось

волновода 12 параллельно поперечной составляющей напряжённости магнитного поля его доминантной волны ТЕ11 вблизи дна 2 чаши 1. Inside the waveguide 12 are two identical coaxial open circular conductors 13 and 14, the axis

which is parallel to the axis

Cartesian coordinate system and located below it inside the waveguide at a distance

from the flat thin bottom 2 of the bowl 1 (Fig. 2; here the side wall 3 is not shown conventionally in full and the bottom 2 is partially, - it is shown only within the end of the waveguide 12). Themselves identical open circular conductors 13 and 14 are made of wire, the radius of which is equal to the radius of the solid inner conductors 10 and 11 of the segments of identical coaxial lines 6 and 7 (Fig. 2, Fig. 3). Moreover, in FIG. 3 (with respect to proportions, but not to scale) shows a longitudinal section of the proposed TADV plane passing through the axis of the inner conductor 10 of a segment of coaxial line 6 perpendicular to both parallel axes located under each other: as axes

and axis

, and in position 15 (a small marker in a circle) shows the projection of the common axis

coaxial open circular conductors 13 and 14 directed towards the reader from the plane of the drawing (that is, "towards us"). At the same time, large markers without circles in positions 16 indicate the directions of the transverse components of the magnetic field of the dominant TE11 wave passing inside the waveguide 12 in the region of the bottom 2, oriented from the plane of the drawing also "towards us". As a result, segments 6, 7 of identical coaxial lines (segment 7, parallel to segment 6, is not shown in Fig. 3, since it does not fall into the plane of said longitudinal section) are spaced apart relative to the axis

circular waveguide 12 in opposite directions (Fig. 1) along the line "a" - "a" passing through the axis

waveguide 12 parallel to the transverse component of the magnetic field strength of its dominant wave TE11 near the bottom 2 of the bowl 1.

в волноводе, что также отражено на фиг. 3 стрелками обратного направления (позиции 19; эти стрелки/(силовые линии) расположены также за секущей плоскостью), исходящими из крестиков второй петли магнитного поля волны ТЕ11. Иными словами, на отрезке

вдоль оси

волновода укладываются две замкнутых петли силовых линий магнитного поля.For a better perception of the principle of operation of the antenna (see below), it is advisable to emphasize that the magnetic field lines of the TE11 wave of a circular waveguide have the form of elongated closed loops inside it, as evidenced by the work of N.N. Fedorov, "Fundamentals of electrodynamics", M .: "Higher school", 1965, paragraph 17.4, fig. 17.6. Therefore, in FIG. 3, lines with arrows (position 17) show the visible parts of these loops behind the plane of the circular conductor 14 (in order not to complicate Fig. 3, only five such parts are shown), and the directions of the arrows 17 correspond to the fact that the lines of force 17, being in the waveguide 12 near the bottom 2 of the bowl 1 behind the plane of the ring conductor 14, very quickly change their direction and then orient themselves along the axis 15 of the collinear ring conductors 13 14, becoming directed near the bottom 2 towards the reader (that is, "towards us") and, therefore, perpendicular to the above-mentioned secant plane coinciding with the plane of the annular conductor 14. Deep in the waveguide, these lines of force are directed away from the reader, which is reflected in FIG. 3 with crosses (position 18) at the beginning of arrows 17 located behind the cutting plane. It is also advisable to note that the directions of the magnetic field lines of the dominant TE11 wave change after half of its length

in the waveguide, which is also reflected in FIG. 3 by arrows of the opposite direction (positions 19; these arrows / (lines of force) are also located behind the secant plane), emanating from the crosses of the second loop of the magnetic field of the TE11 wave. In other words, on the segment

along the axis

the waveguide is fitted with two closed loops of the magnetic field lines.

, отсчитываемый от центров кольцевых проводников (фиг. 3, позиция 15) до средней линии провода разомкнутого кольца. Размыкание кольцевых проводников 13 и 14 реализовано за счёт отсутствия части проволочного кольца на участке

вдоль средней линии кольца от оси волновода

по часовой стрелке (фиг. 3). As a result of this arrangement of antenna elements, the magnetic field lines of the TE11 wave are perpendicular to both parallel planes of identical collinear open ring conductors 13 and 14 having a radius

, measured from the centers of the ring conductors (Fig. 3, position 15) to the center line of the open ring wire. Opening of the ring conductors 13 and 14 is realized due to the absence of a part of the wire ring in the section

along the centerline of the ring from the axis of the waveguide

clockwise (Fig. 3).

The above TADV elements are connected as follows.

кольцевых проводников 13 и 14, которая параллельна линии «а»-«а» разнесения отрезков коаксиальных линий 6 и 7, отстоит внутри волновода от наружной стороны дна 2 чаши 1 на расстоянии

, равном 1,25 их радиуса

(фиг. 3):

. Одноимённые концы 24 и 25 идентичных коллинеарных излучающих проводников 4 и 5 (фиг. 2, на этой фигуре одноимённые концы являются левыми у обоих вытянутых тонких цилиндрических сплошных проводников 4 и 5) гальванически соединены с внешними концами внутренних сплошных проводников 10 и 11 соответственно, причём длина

излучающих проводников 4 и 5 равна 0,9 расстояния

между осями разнесённых отрезков коаксиальных линий 6 и 7 (фиг. 2):

. Внешние концы 26 и 27 наружных трубчатых проводников 8 и 9 этих отрезков 6 и 7 разомкнуты, то есть находятся в режиме «холостого хода» (ни с чем не соединены).The outer side of the bottom 2 of the bowl 1 (Fig. 1) is galvanically connected (for example, by soldering or welding) to one of the ends of the round waveguide 12. The deep with respect to the bowl 1 ends 20 and 21 of the tubular outer conductors 8 and 9, respectively (Fig. 2) connected galvanically (also by soldering or welding) with the inner surface of the flat bottom 2 of the bowl 1, in which holes were previously made in the required place, the diameter of which is equal to the inner diameter of the tubular outer conductors 8 and 9. In turn, the deep ends 22 and 23, respectively, of the inner solid conductors 10 and 11, passing inside the waveguide 12 through the holes in the bottom 2 of the bowl 1, are galvanically connected to the same ends of the corresponding open circular conductors 14 and 13 (Fig. 2, Fig. 3, where, in order to avoid misunderstandings, it is advisable to emphasize that the correspondence of positions is as written above: conductor 10, its end 22, ring conductor 14). It is appropriate to emphasize here that the term "like ends" of the previous sentence means the fact that these ends lie on the longitudinal axes of the inner solid conductors 10 and 11 so that galvanic connections with their respective ends 22 and 23 can be realized. In this case, the common axis

ring conductors 13 and 14, which is parallel to the line "a" - "a" separation of the segments of coaxial lines 6 and 7, is spaced inside the waveguide from the outer side of the bottom 2 of the bowl 1 at a distance

equal to 1.25 of their radius

(fig. 3):

... The ends of the same name 24 and 25 of identical collinear radiating conductors 4 and 5 (Fig. 2, in this figure, the ends of the same name are left in both elongated thin cylindrical solid conductors 4 and 5) are galvanically connected to the outer ends of the inner solid conductors 10 and 11, respectively, and the length

radiating conductors 4 and 5 is 0.9 distance

between the axes of the spaced segments of the coaxial lines 6 and 7 (Fig. 2):

... The outer ends 26 and 27 of the outer tubular conductors 8 and 9 of these segments 6 and 7 are open, that is, are in the "idle" mode (not connected to anything).

The input of the proposed TADV during transmission or its output during reception is the second end of the round waveguide 12, which for this purpose is equipped with a corresponding coaxial-waveguide adapter or a round flange (adapter / flange is not conventionally shown in Figures 1, 2 and 3) for connection to receiving and transmitting equipment, including when using shells and homing missiles in the warheads. In the latter case, the front part of the cylindrical metal body of the projectile / rocket, covered in the nose with a radio-transparent conical fairing, plays the role of a thin cylindrical side wall 3 of bowl 1 of the proposed TADV, which is illustrated by Figure 4, in which, for clarity, the bottom 2 of bowl 1 is conventionally shown only within end face of a circular waveguide 12.

The principle of operation of the proposed TADV is as follows.

с частотой

, амплитуда которого остаётся неизменной в некоторой полосе частот

:Let from the source of harmonic microwave oscillations of the centimeter wavelength range through the coaxial-waveguide adapter, which is conventionally not shown in Figures 1 - 4, a signal is supplied to the circular waveguide 12

with frequency

, the amplitude of which remains unchanged in a certain frequency band

:

, (1)

, (one)

- амплитуда гармонического колебания,Where

- the amplitude of the harmonic vibration,

- время,

- time,

- начальная фаза колебания,

- the initial phase of the oscillation,

- текущая частота,

,

- current frequency,

,

- нижняя и верхняя границы частотного диапазона.

- the lower and upper limits of the frequency range.

волновода 12 выбран из условия [см. вышеупомянутую работу Н.Н. Фёдорова, параграф 17.4, стр. 223, формула (17.27)]If the radius

waveguide 12 is selected from the condition [see. the above work by N.N. Fedorov, paragraph 17.4, p. 223, formula (17.27)]

, (2)

, (2)

- длина волны, соответствующая текущей частоте,Where

- the wavelength corresponding to the current frequency,

- внутренний радиус волновода 12,

- the inner radius of the waveguide 12,

- скорость света в свободном пространстве, окружающем волновод,

- the speed of light in free space surrounding the waveguide,

доминантной волны ТЕ11 внутри волновода 12 определяется как [см. вышеупомянутую работу Н.Н. Фёдорова, параграф 17.4, стр. 223, формула (17.23 «штрих»), параграф 19.4, стр. 247-248]: then, with the corresponding structure of the adapter, a dominant TE11 wave is excited inside the waveguide 12, the structure of the magnetic field lines of which corresponds to figure 3 (positions 16, 17, 18 and 19). If the waveguide 12 is filled with a medium whose parameters coincide with the surrounding free space (for example, air), then the length

dominant wave TE11 inside the waveguide 12 is defined as [see. the above work by N.N. Fedorov, paragraph 17.4, p. 223, formula (17.23 "stroke"), paragraph 19.4, pp. 247-248]:

, (3)

, (3)

- длина доминантной волны внутри волновода 12,Where

- the length of the dominant wave inside the waveguide 12,

- критическая длина доминантной волны ТЕ11.

is the critical length of the dominant TE11 wave.

циклически с частотой

, то согласно закону Ампера это поле индуцирует на поверхности (но не в объёме вследствие «скин-эффекта» на частотах сантиметрового диапазона) кольцевого проводника 14 ток проводимости

, направление которого подчиняется правилу «буравчика» и показано на фиг. 5 для того момента времени, когда, в отличие от фиг. 3, поперечные составляющие силовых линий 28 магнитного поля направлены «от нас» в плоскость чертежа. Этот поверхностный ток

практически без потерь переходит (другими словами: продолжает далее течь) на поверхность глубинного конца 22 внутреннего проводника 10 отрезка 6 коаксиальной линии, так как конец 22 гальванически соединён с кольцевым проводником 14. Далее этот поверхностный ток протекает по поверхности внутреннего проводника 10 отрезка 6 коаксиальной линии и поступает в точку гальванического соединения конца 24 излучающего проводника 4 и внешнего конца внутреннего проводника 10 отрезка 6 (фиг. 5). Вследствие упомянутых гальванических соединений гармонический во времени поверхностный ток проводимости

продолжает течь теперь уже по поверхности излучающего проводника 4. Комплексная амплитуда

этого тока

(фиг. 5) в какой-то мере отличается от комплексной амплитуды

тока

кольцевого проводника 14, так как из-за неоднородностей в зонах вышеупомянутых гальванических соединений, а также вследствие произвольного выбора (иными словами: выбора без настройки/регулировки предлагаемой ТАДВ) волнового сопротивления

отрезка 6 коаксиальной линии, возникают заметные отражения половины сигнала

[формируемого согласно формулы (1)], приходящейся на один из двух идентичных разомкнутых кольцевых проводников 13 и 14. Эти нежелательные отражения сводятся к минимуму за счёт оптимального выбора геометрических размеров и электрических параметров ключевых элементов ТАДВ (иными словами: за счёт правильной настройки ТАДВ, см.. далее). При этом следует подчеркнуть, что излучающий проводник 4 изображён на фиг. 5 для наглядности (то есть, условно) под углом к сплошному внутреннему проводнику 10 отрезка 6, хотя на самом деле излучающий проводник 4 должен быть перпендикулярен плоскости чертежа фигуры 5.As a result, the transverse lines of force 16 of the magnetic field of the dominant wave TE11 near the bottom 2 of the bowl 1 inside the waveguide 12 penetrate the plane of the open circular conductor 14 being perpendicular to it (Fig. 3). Since the intensity of the magnetic field and the direction of its lines of force change in time

cyclically with frequency

, then according to Ampere's law this field induces on the surface (but not in the volume due to the "skin effect" at frequencies of the centimeter range) of the ring conductor 14 a conduction current

, the direction of which obeys the “gimlet” rule and is shown in FIG. 5 for the point in time when, in contrast to FIG. 3, the transverse components of the magnetic field lines 28 are directed "away from us" into the plane of the drawing. This surface current

practically without loss passes (in other words: continues to flow further) to the surface of the deep end 22 of the inner conductor 10 of the section 6 of the coaxial line, since the end 22 is galvanically connected to the ring conductor 14. Further, this surface current flows along the surface of the inner conductor 10 of the section 6 of the coaxial line and enters the point of galvanic connection of the end 24 of the radiating conductor 4 and the outer end of the inner conductor 10 of the segment 6 (Fig. 5). Due to the mentioned galvanic compounds, the time-harmonic surface conduction current

continues to flow now over the surface of the radiating conductor 4. The complex amplitude

this current

(Fig. 5) is somewhat different from the complex amplitude

current

ring conductor 14, since due to inhomogeneities in the zones of the above-mentioned galvanic connections, as well as due to an arbitrary choice (in other words: selection without setting / adjusting the proposed TADV) wave impedance

segment 6 of the coaxial line, there are noticeable reflections of half of the signal

[formed according to formula (1)], falling on one of two identical open ring conductors 13 and 14. These unwanted reflections are minimized due to the optimal choice of geometric dimensions and electrical parameters of the key elements of the TADV (in other words: due to the correct setting of the TADV, see below). It should be emphasized here that the radiating conductor 4 is shown in FIG. 5 for clarity (that is, conventionally) at an angle to the solid inner conductor 10 of the segment 6, although in fact the radiating conductor 4 should be perpendicular to the plane of the drawing of figure 5.

и

, то есть:

. В то же время, поперечные участки симметричных относительно оси волновода

силовых линий 29 магнитного поля волны ТЕ11 вблизи дна 2 чаши 1 (фиг. 6) пронизывают плоскости обоих идентичных разомкнутых кольцевых проводников 13 и 14, которые расположены также симметрично относительно оси волновода. Поэтому комплексные амплитуды

и

гармонических поверхностных токов проводимости (фиг. 6)The underlined feature of the conditional drawing in Fig. 5 of the conductor 4 is eliminated in FIG. 6, which shows both identical radiating conductors 4 and 5 with the corresponding elements, and the planes of the corresponding open circular conductors 14 and 13 are no longer visible, since their "crescent" shapes are projected into short solid objects "b14" - "b14" and "b13 "-" b13 ", respectively, painted in dark gray. In this case, both the radiating conductors 4 and 5 and the corresponding open ring conductors 14 and 13 are identical, and the segments 6 and 7 of the coaxial lines are also identical when their wave impedances are equal

and

, i.e:

... At the same time, the transverse sections symmetric about the waveguide axis

The lines of force 29 of the magnetic field of the TE11 wave near the bottom 2 of the bowl 1 (Fig. 6) penetrate the planes of both identical open circular conductors 13 and 14, which are also arranged symmetrically relative to the waveguide axis. Therefore, the complex amplitudes

and

harmonic surface conduction currents (Fig. 6)

,

, (4)

,

, (four)

which are carried on their surface by the radiating conductors 4 and 5, will be equal:

, (5)

, (five)

- амплитуды поверхностных токов проводимости,Where

- amplitudes of surface conduction currents,

- их начальные фазы,

- their initial phases,

определяются как:and the complex amplitudes

defined as:

,

. (6)

,

... (6)

и

токов на находящихся под потенциалом мощности доминантной волны ТЕ11 волновода 12 одноимённых концах 24 и 25 излучающих проводников 4 и 5 соответственно должны быть равны, то есть:

. В то же время амплитуды токов на обоих одноимённых разомкнутых противоположных концах проводников 4 и 5 должны быть равны нулю. Пренебрегая согласно вышеупомянутой работе Г.Т. Маркова, Д.М. Сазонова «Антенны», глава 2 величиной расстояния между смежными концами излучающих проводников 4 и 5 в области начала декартовых координат

по сравнению с их длиной

, можно записать следующие координатные граничные условия для гармонических токов (4):Thus, the emitter of the proposed TADV, consisting of two identical thin collinear solid radiating conductors 4 and 5, is powered by two equal in-phase surface currents (4), respectively. These currents are distributed over the cylindrical surface of conductors 4 and 5 so that the electromagnetic field excited by them in the surrounding free space satisfies Maxwell's equations, as evidenced by materials related to arbitrary thin wire antennas, including classical dipoles, published in the work: G.T. Markov, D.M. Sazonov, "Antennas", M .: "Energy", 1975, chapter 2, p. 49, third paragraph. In addition, currents (4) must obey the boundary conditions on conductors 4 and 5, according to which the amplitudes

and

currents at the power potential of the dominant wave TE11 of the waveguide 12 of the same ends 24 and 25 of the radiating conductors 4 and 5, respectively, should be equal, that is:

... At the same time, the amplitudes of the currents at both of the same open opposite ends of conductors 4 and 5 should be zero. Neglecting, according to the above-mentioned work of G.T. Markova, D.M. Sazonov's "Antennas", Chapter 2 by the distance between adjacent ends of the radiating conductors 4 and 5 in the region of the origin of Cartesian coordinates

compared to their length

, the following coordinate boundary conditions for harmonic currents can be written (4):

,

, (7)

,

, (7)

,

, (8)

,

, (8)

амплитуда токов на концах 24 и 25 проводников 4 и 5.Where

the amplitude of the currents at the ends 24 and 25 of conductors 4 and 5.

и

поверхностных электрических токов (4) вдоль продольной координаты

(фиг. 2) заранее неизвестны и должны быть определены в ходе решения так называемой внутренней задачи для предлагаемой ТАДВ. После нахождения распределения токов определяется напряжённость электрического поля According to the above-mentioned work of G.T. Markova, D.M. Sazonov "Antennas", p. 50, second paragraph, distribution functions

and

surface electric currents (4) along the longitudinal coordinate

(Fig. 2) are unknown in advance and must be determined in the course of solving the so-called internal problem for the proposed TADV. After finding the current distribution, the electric field strength is determined

(9)

(9)

окружающего пространства, затем форма диаграммы направленности и входное комплексное сопротивление антенны, что составляет сущность внешней задачи для предлагаемой ТАДВ.at any point

surrounding space, then the shape of the directional pattern and the input complex impedance of the antenna, which is the essence of the external problem for the proposed TADV.

), то токи

и

создают в произвольной точке

окружающего антенну пространства векторный потенциал

, у которого значимой/существенной является только продольная составляющая

:Since the radiating conductors 4 and 5 are thin (that is, their radius

), then currents

and

create at an arbitrary point

the space surrounding the antenna vector potential

, in which only the longitudinal component is significant / significant

:

, (10)

, (ten)

- есть продольная составляющая векторного потенциала,Where

- there is a longitudinal component of the vector potential,

- орт оси

декартовой системы координат (фиг. 2).

- axis unit

Cartesian coordinate system (Fig. 2).

напряжённости электрического поля (9), которая на поверхности излучающих проводников 4 и 5 (где

), будучи одновременно тангенциальной/касательной составляющей, согласно вышеупомянутой работы Г.Т. Маркова, Д.М. Сазонова «Антенны», глава 2, должна быть равна нулю:The known potential (10) is used to find the longitudinal component

electric field strength (9), which on the surface of radiating conductors 4 and 5 (where

), being at the same time a tangential / tangent component, according to the aforementioned work of G.T. Markova, D.M. Sazonov's "Antennas", Chapter 2, should be zero:

, (11)

, (eleven)

- электрическая и магнитная постоянные вакуума соответственно,Where

- electric and magnetic vacuum constants, respectively,

- относительная диэлектрическая и магнитная проницаемости окружающего антенну пространства,

- relative permittivity and permeability of the space surrounding the antenna,

- круговая частота гармонического сигнала доминантной волны ТЕ11 круглого волновода 12 [фиг. 2, формула (1)],

- the circular frequency of the harmonic signal of the dominant wave TE11 of the circular waveguide 12 [Fig. 2, formula (1)],

- радиус тонких цилиндрических излучающих проводников 4 и 5 (

).

- radius of thin cylindrical radiating conductors 4 and 5 (

).

[размерность этой поверхностной плотности: (ампер/метр)] электрических токов на боковых цилиндрических поверхностях тонких сплошных проводников 4 и 5 соотношением:In turn, the vector potential (10) is related according to the above-mentioned work by G.T. Markova, D.M. Sazonova "Antennas", section 2, with surface density

[dimension of this surface density: (ampere / meter)] electric currents on the lateral cylindrical surfaces of thin solid conductors 4 and 5 by the ratio:

, (12)

, (12)

- длина радиуса-вектора произвольной точки наблюдения

, иными словами: расстояние от начала декартовых координат до точки наблюдения,Where

is the length of the radius vector of an arbitrary observation point

, in other words: the distance from the origin of the Cartesian coordinates to the observation point,

- есть полный продольный поверхностный ток на излучающих проводниках 4 и 5, причём интегрирование вдоль проводников ведётся по «штрихованной» координате

, совпадающей с осью

.

- there is a total longitudinal surface current on the radiating conductors 4 and 5, and the integration along the conductors is carried out along the "hatched" coordinate

coinciding with the axis

...

согласно методике, описанной в работе Г.Н. Кочержевский, «Антенно-фидерные устройства», М.: «Связь», 1972 год, 472 стр., илл., можно записать следующее дифференциальное уравнение относительно неизвестного пока ещё тока

, распределённого вдоль оси

тонких излучающих проводников 4 и 5 (фиг. 2):After substitution of (12) in (11) and a number of transformations, including the return from the "hatched" coordinate to the "unhatched"

according to the method described in the work of G.N. Kocherzhevsky, "Antenna-feeder devices", M .: "Svyaz", 1972, 472 pages, ill., You can write the following differential equation for the still unknown current

distributed along the axis

thin radiating conductors 4 and 5 (Fig. 2):

, (13)

, (thirteen)

- волновое число свободного пространства, окружающего предлагаемую ТАДВ.Where

is the wavenumber of free space surrounding the proposed TADV.

-ого порядка:The written equation (13) is at the same time a special case of a homogeneous linear differential equation of an arbitrary

-th order:

, (14)

, (14)

,

,

,

, индексы в верхних круглых скобках означают номер производной, например:

- вторая производная,

- сама функция без производной.Where

,

,

,

, the indices in the upper parentheses indicate the derivative number, for example:

- the second derivative,

- the function itself without a derivative.

непрерывны на отрезке

. Как известно из курса высшей математики, фундаментальное решение общего уравнения (14) формируется из линейной комбинации

любых линейно независимых частных решений. Это решение принято формировать по методу Эйлера, согласно которому при

имеем:In this case, it is assumed that both the first and second derivatives of the current, as well as the stream function itself

continuous on the segment

... As is known from the course of higher mathematics, the fundamental solution to the general equation (14) is formed from a linear combination

any linearly independent particular solutions. It is customary to form this decision by the Euler method, according to which for

we have:

, (15)

, (15)

и

- пока ещё произвольные постоянные,Where

and

- still arbitrary constants,

и

- функции, определяемые корнями

характеристического уравнения

and

- functions defined by roots

characteristic equation

, (16)

, (16)

и

.what gives:

and

...

весьма тонких (в пределе: бесконечно тонких или «нитевидных») излучающих проводников 4 и 5 (фиг. 2) записывается как:As a result, the general solution of the differential equation (13) with respect to the conduction current flowing along the axis

very thin (in the limit: infinitely thin or "threadlike") radiating conductors 4 and 5 (Fig. 2) is written as:

.

...

и

, что приводит к следующему выражению для «нитевидного» тока проводимостиAfter imposing the boundary conditions (7) and (8) on this equation, the constants

and

, which leads to the following expression for the "threadlike" conduction current

,

, (17)

,

, (17)

для предлагаемой ТАДВ (фиг. 1), характеризующей электромагнитное поле в произвольной точке

наблюдения, находящейся в дальней зоне Фраунгофера, где

.and also allows you to start solving the external problem, during which the radiation pattern equation will be found

for the proposed TADV (Fig. 1), characterizing the electromagnetic field at an arbitrary point

observations located in the far-field of Fraunhofer, where

...

предлагаемой ТАДВ. В результате после соответствующих преобразований, включая двукратное интегрирование по частям, искомая диаграмма направленности определяется как:The procedure for forming the equation for the radiation pattern of the proposed TADV (Fig. 1) is similar to that described in the above-mentioned work by G.T. Markova, D.M. Sazonov "Antennas", sections 2-3, 2-4, pp. 57-64, with the difference that instead of equation (2-19) for the current of the classical dipole in this work, below is used equation (17) for the current

the proposed TADV. As a result, after appropriate transformations, including double integration by parts, the desired radiation pattern is determined as:

,

,

,

,

, (18)

, (eighteen)

отсчитывается от оси

.where is the angle

measured from the axis

...

магнитного вектора Н. По оси лучение отсутствует, а во всех остальных направлениях оно является линейно поляризованным: плоскость поляризации, в которой лежит вектор напряжённости электрического поля Е, проходит через точку наблюдения

дальней зоны Фраунгофера и ось

проводников 4 и 5. Таким образом, сечение объёмной диаграммы направленности в форме тора уединённого излучателя из проводников 4 и 5 в отсутствие чаши 1 любой плоскостью поляризации (другими словами: любой плоскостью электрического вектора Е, - таких плоскостей бесчисленное множество) представляет собой «восьмёрку», максимумы которой лежат на оси

(фиг. 1). В то же время, сечение тора единственной плоскостью

магнитного вектора Н представляет собой круг, то есть, уединённый излучатель из проводников 4 и 5 без чаши 1 является всенаправленным.The result obtained indicates that the directivity pattern of a solitary emitter consisting of two identical thin radiating conductors 4 and 5 in the absence of bowl 1 is a bulk torus with maxima lying in the plane

the magnetic vector H. On the axis, the radiation is absent, and in all other directions it is linearly polarized: the plane of polarization, in which the electric field strength vector E lies, passes through the observation point

far Fraunhofer zone and axis

conductors 4 and 5. Thus, the cross-section of the three-dimensional radiation pattern in the form of a torus of a solitary emitter from conductors 4 and 5 in the absence of bowl 1 with any plane of polarization (in other words: any plane of the electric vector E, there are countless such planes) is a "figure eight" , the maxima of which lie on the axis

(Fig. 1). At the same time, the section of the torus by the only plane

magnetic vector H is a circle, that is, a solitary emitter from conductors 4 and 5 without bowl 1 is omnidirectional.

в её положительном направлении (фиг. 1), причём подбором геометрических размеров (иными словами: за счёт настройки) ТАДВ можно обеспечить одинаковую ширину главного лепестка диаграммы направленности в вышеуказанных Е- и Н-плоскостях. Максимум главного лепестка будет направлен по оси питающего волновода 12 в окружающее свободное пространство впереди него. При этом целесообразно подчеркнуть, что, глядя из произвольной точки

дальней зоны Фраунгофера (где

), совершенно невозможно даже разглядеть антенну, не говоря уже о том, чтобы различить между собой оси

декартовой системы и

круглого волновода 12. Для примера достаточно представить себе ситуацию, когда расстояние

от предлагаемой ТАДВ сантиметрового диапазона до точки наблюдения

в дальней зоне составляет порядка двух-трёх километров. Иными словами, для всех точек наблюдения в дальней зоне Фраунгофера и, следовательно, для всех диаграмм направленности, расстоянием

между осями

и

(фиг. 2) можно пренебречь, то есть, диаграммы направленности инвариантны относительно этого расстояния.However, the presence of bowl 1 significantly changes the shape of the radiation pattern (21): it becomes unidirectional with a single maximum lying on the axis

in its positive direction (Fig. 1), and by selecting the geometric dimensions (in other words: by adjusting) the TADV can provide the same width of the main lobe of the radiation pattern in the above E- and H-planes. The maximum of the main lobe will be directed along the axis of the feed waveguide 12 into the surrounding free space ahead of it. In this case, it is advisable to emphasize that, looking from an arbitrary point

Fraunhofer far zone (where

), it is completely impossible even to see the antenna, let alone to distinguish between the axes

Cartesian system and

circular waveguide 12. For example, it suffices to imagine a situation where the distance

from the proposed TADV centimeter range to the observation point

in the far zone is about two to three kilometers. In other words, for all observation points in the Fraunhofer far field and, therefore, for all radiation patterns, the distance

between axles

and

(Fig. 2) can be neglected, that is, the radiation patterns are invariant with respect to this distance.

сигнала (1)] обмена реактивной мощностью между пространством зоны Френеля и излучателем, состоящем из излучающих проводников 4 и 5 (фиг. 1). В этой зоне векторы напряжённостей создаваемых излучающими проводниками 4 и 5 электрического Е и магнитного Н полей не находятся в фазе (см. вышеупомянутую работу Г.Т. Маркова, Д.М. Сазонова, стр. 74) и излучаемая ТАДВ мощность получается комплексной. Комплексным будет и входной импеданс

ТАДВ, который должен быть согласован с вещественным характеристическим сопротивлением круглого волновода 12 за счёт подбора геометрических размеров фрагментов ТАДВ и электрических параметров её ключевых элементов, например, таких как волновые сопротивления

идентичных отрезков коаксиальных линий 6 и 7 (фиг. 1, фиг. 2).A different situation develops in the near Fresnel zone, where, according to the above-mentioned work of G.T. Markova, D.M. Sazonov's "Antennas", paragraph 1-2, p. 24, third paragraph, the electromagnetic field is complex and in its calculation it is necessary to use strict relations of electrodynamics. In the near-field zone, in the general case, all field components are present and their dependence on distance is irregular. In the near zone of any radiating system, including the proposed TADV, there is always a certain amount of electromagnetic energy. In this case, an oscillatory process occurs [with a frequency

signal (1)] the exchange of reactive power between the space of the Fresnel zone and the emitter, consisting of radiating conductors 4 and 5 (Fig. 1). In this zone, the vectors of the intensities created by the radiating conductors 4 and 5 of the electric E and magnetic H fields are not in phase (see the aforementioned work by G. T. Markov, D. M. Sazonov, p. 74) and the radiated TADV power is complex. The input impedance will also be complex.

TADV, which must be matched with the real characteristic impedance of the circular waveguide 12 by selecting the geometric dimensions of the TADV fragments and the electrical parameters of its key elements, for example, such as wave impedances

identical sections of coaxial lines 6 and 7 (Fig. 1, Fig. 2).

As a result, the aforementioned supply of electromagnetic energy in the Fresnel zone makes it difficult to match the TADV input well with the signal source in the frequency band. The analytical formulation of the matching problem and its subsequent algorithmization for computer calculations are possible in relatively simple cases, in particular, when the signal source (1) is concentrated in the gap between the adjacent ends of the radiating conductors 4 and 5. In the proposed TADV, the signal source first excites a waveguide through the adapter 12, then the electromagnetic field of the dominant wave TE11 induces surface currents on the open ring conductors 13 and 14, and then on the radiating conductors 4 and 5 (Fig. 2). Therefore, the selection of the geometric dimensions of the fragments of the proposed TADV and the determination of its optimal electrical parameters (in other words: tuning the TADV) is advisable to be implemented in the system of three-dimensional electrodynamic modeling due to the built-in nonlinear optimizer of geometric and electrical parameters. The system below uses the “WIPL-D” system, previously freely available on the market as an attachment on a CD to B.M. Kolundzija, J.S. Ognjanovic, T.K. Sarkar “WIPL-D: microwave circuit and 3D EM simulation for RF & microwave applications. Software and user’s manual, ”Norwood, MA, Artech House, 2005, 400 pages.

коаксиально-волноводного адаптера не снизился ниже уровня 1,5:

. При этом были достигнуты/найдены следующие вышеупомянутые параметры (в Омах) и геометрические размеры (в миллиметрах), указанные на фигурах 1....6:The optimization (tuning) procedure of the proposed TADV (Fig. 1) in the "WIPL-D" system continued until the input standing wave ratio

coaxial-waveguide adapter did not drop below 1.5:

... At the same time, the following aforementioned parameters (in ohms) and geometric dimensions (in millimeters) indicated in Figures 1 ... 6 were achieved / found:

(19)

(19)

The combination of these parameters provides good matching and at the same time practically the same width of the main lobe of the radiation pattern in the E- and H-planes, directed along the axis of the supply waveguide 12 in the direction of the surrounding free space in front of it.

(фиг. 7, позиция 30) измерен с использованием генератора «качающейся частоты» ГКЧ-57 и индикатора Я2Р-67. Диаграммы направленности ТАДВ измерены по критериям дальней зоны Фраунгофера в безэховых условиях антенной лаборатории с применением стандартных методик калибровки и измерений с использованием вышеупомянутого генератора, микровольтметра-усилителя «В6-4» и поворотных устройств по азимуту и углу места с точностью установки углов 1 градус. После компьютерной обработки результатов измерений на фиг. 8 построены соответствующие диаграммы направленности (позиция 31 представляет диаграмму в Е-плоскости, а позиция 32 - для Н-плоскости), угловая ширина которых по уровню половинной мощности примерно одинакова.To experimentally confirm the results of solving the problem, a prototype of the proposed TADV was manufactured with the above parameters (19). The antenna was powered by a coaxial cable RK-75-7-22 with a characteristic impedance of 75 Ohm through a coaxial-waveguide pin adapter, which was calculated and manufactured in accordance with the standard methodology described in the work: ed. DI. Voskresensky, “Antennas and microwave devices. Calculation and design of antenna arrays and their radiating elements ", Moscow:" Soviet radio ", 1972, paragraph 8.5" Antenna excitation ", pp. 229-231. Input

(Fig. 7, position 30) was measured using a "sweeping frequency" generator GKCH-57 and indicator YA2R-67. The TADV directional patterns were measured according to the Fraunhofer far-field criteria in anechoic conditions of the antenna laboratory using standard calibration and measurement techniques using the aforementioned generator, a V6-4 microvoltmeter-amplifier and rotary devices in azimuth and elevation with an angle setting accuracy of 1 degree. After computer processing of the measurement results in FIG. 8, the corresponding radiation patterns are constructed (position 31 represents the pattern in the E-plane, and position 32 for the H-plane), the angular width of which at the half power level is approximately the same.

и

соответственно (если синфазны токи, то синфазны и напряжения, их создающие), которые подводятся к одноимённым (левым на фиг. 6) концам 24 и 25 соответственно. При этом конец 25 проводника 5 является смежным по отношению к проводнику 4, а конец 24 проводника 4 - удалённым по отношению к проводнику 5. В результате, в предлагаемой ТАДВ используется центрально-концевое питание излучателя дипольного вида равными синфазными токами, в то время как в прототипе применяется классический центрально-питаемый диполь, возбуждаемый на центральных смежных концах (center-fed dipole) двумя равными по модулю, но противофазными токами.This circumstance, along with waveguide 12 and bowl 1 (Fig. 1), was largely facilitated by the fact that, in contrast to the prototype, where the thin radiating conductors of each radiator are called "monopoles", forming a classical center-fed dipole (center-fed dipole, see line 22, column 2 of the prototype description), in the proposed TADV, radiating conductors 4 and 5 form another radiator. Namely: here conductors 4 and 5 form a dipole-type emitter (that is, externally and structurally very similar to a center-fed dipole, but not a dipole nevertheless), which is powered by two equal in-phase harmonic currents

and

accordingly (if the currents are in-phase, then the voltages that create them are also in-phase), which are supplied to the ends of the same name (left in Fig. 6) 24 and 25, respectively. In this case, the end 25 of the conductor 5 is adjacent to the conductor 4, and the end 24 of the conductor 4 is remote with respect to the conductor 5. As a result, in the proposed TADV, the central-end power supply of the dipole-type emitter is used with equal common-mode currents, while in The prototype uses a classic center-fed dipole, excited at the center-fed dipole by two currents of equal magnitude, but antiphase.

Thus, the presented results indicate the solution of the problem: the creation in the centimeter wavelength range of a more technologically advanced end-face dipole antenna with the same width of the main lobe of the radiation pattern in the E- and H-planes, directed along the axis of the supply waveguide in the direction of the surrounding free space in front of it.

These circumstances together make it possible to recommend the proposed TADV for use in promising stationary, mobile and rocket radio systems of the centimeter range with linear polarization of emitted / received radio signals.

Claims (1)

An end-face dipole antenna containing a cylindrical metal bowl with a flat bottom, a thin lateral cylindrical wall and an open end, a radiator located outside the bowl parallel to the plane of the end near it, consisting of two identical elongated collinear thin cylindrical solid radiating conductors, the length of which does not exceed the bowl radius, a pair of identical coaxial line segments orthogonal to the bottom, the length of which exceeds the depth of the bowl, consisting of tubular outer and solid inner conductors, while the deep ends of the outer conductors of the segments are galvanically connected to a flat bottom, the deep ends of the inner conductors of the segments pass through the bottom of the bowl through circular holes in it , the diameter of which is equal to the inner diameter of the tubular outer conductors, characterized in that it additionally contains a segment of a circular waveguide operating on the dominant TE11 wave, the diameter of which is less than the diameter of the bowl, and two identical coaxial open circular conductors, the diameter of which does not exceed the radius of the circular waveguide, while the outer side of the bottom of the bowl is galvanically connected to one of the ends of the circular waveguide as follows that the axis of the bowl does not coincide with the axis of the circular waveguide, segments of identical coaxial lines are spaced relative to the axis of the waveguide in opposite directions along a line passing through the axis of the waveguide parallel to the transverse component of the magnetic field strength of the dominant TE11 wave passing inside the bowl near the bottom of the bowl, the deep ends of the internal solid conductors of the aforementioned segments, passing inside the circular waveguide through the holes in the bottom of the bowl, are galvanically connected to the same ends of the open circular conductors, the common axis of which is parallel to the separation line of the coaxial line segments and is spaced inside the waveguide from the outer side of the bottom of the bowl at a distance equal to 1.25 of their radius, the ends of the cylindrical collinear radiating conductors of the same name are galvanically connected to the outer ends of the inner solid conductors of the mentioned sections of coaxial lines, while the length of the radiating conductors is equal to 0.9 distance between the axes of spaced segments of coaxial lines , the outer ends of the outer tubular conductors of which are open, and the second end of the circular waveguide is the input / output of the antenna.

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