JPH04805A - Antenna equipment - Google Patents

Abstract

PURPOSE:To simplify feeders near a radiator and to improve the symmetry of power feeding by counter arranging two radiators while being rotated at 180 deg. each other for each power feeding point and using a phase inversion bisectional branching circuit utilizing a magnetic field coupling operation mutually between strip lines as a bisectional branch circuit to distribute signals from the feeders to the individual feeders of the two radiators as mentioned above. CONSTITUTION:Since strip lines 53 and 56 are arranged at a place where a line voltage is minimum and a line current is maximum to strip lines 52 and 57, and coupling is executed by the magnetic field of a high frequency. Therefore, the unidirectional current is induced to the strip lines 53 and 56, and the signal inverting the phase is sent in the directions of the radiators of the respective individual feeders. The signal applied to a feeder 59 is equally divided into four parts and simultaneously, patch radiators 32 and 36, which are mutually rotated at 180 deg., and patch radiators 42 and 47 are excited because of phase inversion bisectional branch circuits 52 and 57. Finally, all the radiators are coaxially excited.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention uses an IJ line as a power supply line,
The present invention relates to an antenna device that excites a plurality of radiating elements.

[Prior Art] In general, a flat antenna for receiving satellite broadcasting is required to have a high gain, has a large area, has a large number of radiating elements arranged on a plane, and each radiating element is coupled to a feed line.

Conventionally, a strip line, which is suitable for being lightweight and compact, has been used as a feed line for a planar antenna.

Further, as the strip line, a microstrip line consisting of a ground conductor and a strip conductor, or a trigrate strip 7''41M- consisting of a three-layer conductor layer in which a strip conductor is arranged between upper and lower ground conductors is used.

Generally, when a microstrip line is used as a feed line, the radiating element is a half-wavelength microstrip line with both ends open. - The Gutsuchi antenna and the AM feed path are directly coupled. In the case of true tri-rate strip line power feeding, a slot antenna type antenna in which a slot with a length of 1/2 tIL is provided in the upper ground conductor is used, and the slot antenna and the feeding tS path are often electromagnetically coupled. Furthermore, as for the overall power feeding method, in the case of strip line power feeding, a parallel feeding method is used in which a parallel feeding method is used in which two branch circuits are combined, so that the line length from one feeding point to each radiating element is equal. The spacing between each radiating element is determined to suppress unnecessary side ropes and prevent deterioration of antenna radiation efficiency.
They must be densely arranged in the 0.05 wavelength to 0.9 wavelength radius.

However, in planar antennas using these strip lines, in order to excite the radiating element with a desired phase and uniform amplitude, the arrangement of the individual feed lines around the radiating element requires complicated and overcrowded wiring. There was a problem in that mutual interference between the lines occurred, impairing uniform excitation, and as a result, the radiation efficiency of the antenna decreased.

Furthermore, in conventional planar antennas, there was a problem that the matching circuit between the radiating element and the antenna element was not optimal due to restrictions on the arrangement of the individual feed lines around the radiating element, resulting in a narrow band as a whole. FIG. 5 shows a plan view of a planar antenna using a conventional strip line feeding system. This antenna is arranged so that the radiated power of each radiating element is combined in the E-opening direction perpendicular to the plane.

4' @ circular/4-titch radiating element, ? , 7, 17
, 15 are individual feed lines 6, 10, 14 . In-phase power is supplied in the same direction by III. +1iil separate payment tS road 6.10, 14.18 is T
1/4 wavelength I/
- Combined into one feed line 24 from a T branch xsv'c including a line portion 20° 21 serving as a one-dance transformer.

Each circular segment has a cutout segment at a 45 degree angle from the feed point)4*5eJe9*12.13. By holding the groove 17, two orthogonal resonant modes [90 degree phase difference are imparted to the disk conductor, and circularly polarized waves are generated by exciting with equal amplitude.

[Problems to be Solved by the Invention] The problem with the above feed line arrangement is that the feed line 2 of the T branch 23 is
Near the T branch of 4 is the track 2o...? Since it is not orthogonal to J, it is not completely bifurcated due to asymmetric magnetic field coupling, and the power distribution becomes uneven between the left and right sides. It has been experimentally known that the coupling to the line portion 20, which is the left branch, becomes stronger.

Further, the feed line 24 approaches the individual feed line 14 and the radiating element 15, causing unnecessary electromagnetic coupling, resulting in non-uniform excitation of each radiating element, resulting in a decrease in antenna efficiency.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an antenna device that can simplify the configuration, reduce loss in the feed line, and improve antenna efficiency.

[Means and effects for solving the problem] The present invention includes two radiating elements that are rotated 180 degrees and placed facing each other at each feeding point, and a signal is transmitted from the feeding line to the individual feeding line of the two radiating elements. By using a phase-inverting two-branch circuit that utilizes the magnetic field coupling effect between strip lines as a two-branch circuit for distribution, the feed line near the radiating element can be simplified, and the symmetry of the feed can be improved to improve the feed line. This makes it possible to improve antenna efficiency by reducing unnecessary coupling and uniformizing the excitation of the radiating element.

Mouth 1st example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a planar antenna according to a first embodiment of the present invention, and shows the case where the present invention is applied to a triplate type strip line feeding system.

The tri-plate strip line (hereinafter simply referred to as the t-th strip line) consists of an insulator 3 placed above the ground conductor 30 in FIG. It is formed at a conductor layer that is located between the insulator 60 and the insulator 60 that is located on the side.

The format of each radiating element is slightly different from the conventional example described earlier, but
Similarly, it is a /f latch radiation element, and is arranged to combine the main beam in the vertical front direction.

The four /# latch radiating elements 32, 37, 42, 41 are spaced apart by the ground conductor 30 and the insulator 31,
Cross grooves 3B, 34 in which a strip-shaped elongated conductor and a slightly wider and shorter conductor are orthogonally crossed at an angle of 45 degrees from each feeding point on the circumference of the disk conductors 35, 40, 45.50.
．． 3B, 39, 43° 44, 48, 49 has a structure that extends, gives a 90 degree phase difference to two orthogonal resonance modes, and generates circularly polarized waves by exciting with equal amplitude. It is.

Patch type radiating elements 32.37 and 72.47 are individual feed lines 36.41 and 46.51 made of strip lines.
, each including a feeding point and arranged 180 degrees rotated from each other. Individual feed lines 36.41 and 46.5
To distribute the signal to 1, phase inversion 2 branch circuit 52.5
7 is used, and these have one open end and 4 points from the open end.
The strip line 53.56 which is bent at the front and back near the current maximum position which is one-quarter wavelength away is the strip line 52゜57
It is constructed close to.

Power supply route 54 with different line width for impedance matching
．． 55 is connected to one feed line 59 via a T-branch 48.

Next, the operation of the circuit and the 4h@ of the radiating element in the construction of the present invention will be explained. Strip line 53.561
d. Since the strip lines 52 and 57 are placed in close contact with each other at the portions where the line voltage is minimum and the line current is maximum, coupling is achieved by a high frequency magnetic field. Therefore, a current in one direction is induced in the strip lines 53 and 56, and signals whose phases are reversed are sent to the direction of the radiating element of each individual feed line.

In this way, the signal added on the power supply line 591Fc is divided into 4 equal parts, and at the same time, 1st opposite 2 branch circuit SX, S.
Because of the radiating elements 32 .
16 and 42°47 @! L, all the radiating elements are excited in the same phase.

Radiation waves from the radiating element are radiated to the outside through openings 62, 63, 64, and 65, which are arranged on the upper ground conductor 61 and have protrusions pointing inward at positions dividing the circumference into four equal parts. The protrusions on the circumference reduce the resonant frequency of the aperture and allow the radio waves to pass through the aperture with a relatively small diameter, thereby increasing the area of the upper ground conductor other than the aperture and eliminating unnecessary parts from the strip feed line section. Radiation can be suppressed.

In the arrangement of this radiating element, the electromagnetic wave radiation is a combination of direct radiation from the Gutsuchi-type radiating element and radiation from the aperture by exciting the aperture.

Since the protrusion of the opening is arranged parallel to the cross section of the lower radiating element, electromagnetic coupling acts to strengthen the excitation by using the opening as a slot radiating element. The function of the aperture as a slot radiating element is maximized when the resonant frequency of the aperture matches the operating frequency, and dominates the overall radiation. On the other hand, if the aperture is made large and the resonant frequency is sufficiently lowered from the operating frequency, radiation from the four-way type radiating element becomes dominant. Although the latter method is simpler in design, the shielding effect of the feed line is slightly reduced, so either method may be selected depending on the purpose.

As an effect of the present invention, phase inversion type two-branch circuit 52.57
Since the t-left and right sides are arranged in a shape with a bowl-like relationship, it is possible to feed power with good symmetry from the center, and uniformly excite the left and right radiating element pairs.

In the above embodiment, the antenna is applied to a flat antenna in which the main beam is perpendicular to the surface, but even when the main beam is arranged at 10 angles, if the design is based on the uninvented feeding method, the feeding line can have a phase difference. By using conventionally well-known methods such as inserting a load circuit and adding different rotation angles to the arrangement of radiating elements and feeding points, the desired beam can be achieved by taking advantage of the fact that wiring can be simpler than before. There is an advantage that tilting can be easily realized.

Please note that in the above embodiment, a circular 9-shaped radiating element was used as the radiating element, and the one-page connection method using individual feed lines was used as the feeding method, but as is often said, the upper ground conductor The present invention can also be applied to a feeding system in which so-called electromagnetic coupling is performed using a nine-slot type sheet radiating element and a tri-plate strip line that crosses the slots of the radiating element.

[Second Embodiment] FIG. 2 is a circuit pattern of a phase inversion type two-branch circuit in a planar antenna according to a second embodiment of the present invention, in which a half-wavelength strip with a bent open end 72.75 is shown. Individual feed lines 74 and 75 are connected to positions slightly apart from both open ends of the line 52. (round, one end open)
+7 Tsug line 76 is bent at right angles to both sides before and after 1/4 wavelength from the open end as shown in the figure, and the line width of the 1/4 wavelength line leading to feed line 79 is changed to operate as an impedance matching device. can be done. The operation as a two-branch circuit is almost the same as that shown in Fig. 1, but by separating the individual feed lines 74, 75 from the open end 72° 75, the matching with the smaller impedance on the radiating element side is improved. , has the effect of making the branch point t- more compact.

[31st! Example] Figure 3 shows the 31st example of the present invention! In the circuit 7 of the phase inversion type two-branch circuit in the planar antenna of the embodiment, the strips @ugs and gy are bent into a U shape and connected at the line part 86 at the bottom, and the length is 1/2 e as a whole. the first of
) Configure the IJ line. Said bottom track section 8
A wide 1/2 wavelength strip line 80 is used as the IJ line, and individual feed lines 83. Ii4 is connected.

A strip line 8 that is extended from the feed line 90 and has a varying width and functions as a quarter-wavelength impedance transformer.
The tip 88 of 9 is bent upward and connected to the strip line 85 from inside the U-shape.

The connection point Fi is the high impedance at the end of the U-shape, and the connection point can be selected as appropriate depending on the design. The operation in this configuration is the same as in the FiK2 diagram, but the vertical symmetry of the coupling portion is improved, and even better characteristics can be expected.

[Fourth Embodiment] FIG. 4 is a configuration diagram of a planar antenna according to still another embodiment of the present invention.

First, the power supply circuit will be explained. A stripline feeder line 1oo is provided between the insulator 31 above the ground conductor 30 and the insulator 6o below the upper ground conductor 61, and the T-branch 101
After passing through phase inversion two-branch circuit 102.103, IJ tube line 104.105, 106, 1 with one end open.
It will be divided into 4 parts in 2007. To explain the upper left block of these blocks, at a quarter wavelength from the open end of the strip line 104 with one end open, folded strip lines 108 and 109 are placed close to each other from the left and right, and magnetic field coupling is achieved. The signal is further divided into four equal parts, and the strip lines 110 and 111 and 112 and 113, which are open at one end and placed in opposite directions, are excited in opposite phases from the feeding point, and when viewed from one direction, the whole It is excited by a vertically directed current. The same goes for the other blocks, which are all excited vertically in the same phase and radiate electromagnetic waves upwards.

Next, the IJ line 1 was installed on the upper ground conductor.
10. Upper left corner corresponding to IIIK+7) 180 [A pair of rotationally arranged apertures will be explained. circular opening 114
, 116 has an inwardly directed fin conductor 115,1.
17 will be provided.

The electromagnetic waves radiated from the strip lines 110, 111 are vertically polarized waves, whereas the original polarization of the radiated waves by the fin conductors 1111, 111 cut at an angle of 45 degrees is
The direction of the fin conductor and this K [When decomposed into two intersecting polarization components and summed to give an inductive actance with an appropriate length of the fin conductor, only the polarization component in the direction of the fin conductor has a 90 degree phase. As a result, circularly polarized waves can be generated. That is, the lowest order mode co-optation #1 wave number of the aperture is set lower than the operating frequency.

It can be made to exhibit inductive reactance and cause narrowing in one day. The same goes for the other aperture pairs, and the circularly polarized waves from all the apertures can be combined in the front direction.

Although a single fin conductor is used in this embodiment, two fin conductors may be provided from the inner periphery on both sides, and circularly polarized waves can be generated using the same principle.

Furthermore, if the above is modified and there are four fin conductors provided in orthogonal directions, the length of the fin conductors is changed so that when one opposing pair is capacitive, the other orthogonal pair is inductive. Adjust the reactance to exactly ±45 between orthogonal
It is possible to obtain circularly polarized waves for four purposes by causing a phase delay of degrees.

[Effects of the Invention] As described above, according to the present invention, as a result of using a phase-inverting two-branch circuit using novel magnetic field coupling in the feed line of a stripline planar antenna, the feed line for the radiating element is The symmetry and simplicity of the antenna have been further improved, and a wide, low-loss strip line can be used for the feed line, making it possible to uniformize the excitation of the radiating element and improve the antenna efficiency by reducing the loss of the feed line. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a planar antenna showing an IEI embodiment of the present invention, and FIGS.
Circuit i- of the phase inversion two-branch circuit of the planar antenna of the embodiment
FIG. 4 is a block diagram of a planar antenna showing a fourth embodiment of the invention, and FIG. 5 is a block diagram of a conventional planar antenna. 1... Ground conductor, 2... Insulator 5. t, 7,
JJ. 15-...Circular/Yatch radiating element, 4, 5, 8, 9°J
2, J3. J 6 , 1 F-... Notch segment, 6.10.14.18-... Individual feeder line,
7,8°z3...T branch, 30...Grounding conductor, 31
．． 60... Insulator, 61... Upper ground conductor, 32,
31.42°47.../# Latch radiation element, 35.4
0.45°50...Disc conductor, 33. :N4. ．． 1g
, 39.43゜44.411.49...Cross/#tsuchi, J 6 e 41 t46.51...1mm separate type electrical line sz, s':r-...Phase inversion 2 branch circuit, ss
, st;, ss, sv... strip line, 59...
・Feed line, 62, 63, 64° 65-・Opening, 74.
75...1 separate feed tS path, 19...power feed line, 85,
117...Strip line, 83゜84...Individual feed line, 90...Feed line, 100...Strip line feed line, 101・-T branch, 102゜z o s-
...Phase inversion 2-branch circuit, 104,105°106.1
0'l...Strip line with one end open, 110, Jl
l, 112, 113... strip line, 114, 1
16...Circular opening, 115.117...Fin conductor.

Claims (3)

[Claims] (1) In an antenna device comprising a plurality of radiating elements and a feed line that branches from one signal terminal into a plurality of strip lines and excites the plurality of radiating elements in a parallel feed system, the feed line As a component of the first
The current maximum position, which is a quarter wavelength away from the open end of the strip line, is placed close to the second strip line, and by inducing a current in the second strip line by magnetic field coupling, the second strip line is An antenna device characterized by using a phase-inverting two-branch circuit in which signals having equal amplitude and a phase difference of 180 degrees are transmitted in both directions of a strip line. (2) In the antenna device according to claim (1), the phase inversion two-branch circuit includes a first strip line with one end open and a second strip line with a line length of 1/2 wavelength and both ends open. A current maximum position, which is a quarter wavelength away from the open end of the first strip line, is located close to the current maximum position in the center of the first strip line, and the connection point of the line from which the two-branch signal is taken out is connected to the second strip line. An antenna device characterized in that it is provided at an open end or closer to the center than the open end. (3) An opening provided in the upper ground conductor of the strip line having an open end allows the radiation waves from the strip line to pass through, and a fin conductor is extended at an angle of 45 degrees around the inner circumference of the opening, and the lowest ground conductor of the opening is An antenna device characterized in that a mode resonance frequency is set lower than an operating frequency and circularly polarized waves are generated by exhibiting inductive reactance.