JP2005072670A - Dual frequency shared dipole antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dual frequency shared dipole antenna device capable of improving vertical plane directivity in an array antenna, and obtaining a horizontal plane directivigy in sharing both horizontal and vertical of dual frequency plane sharing which is structural impossible. <P>SOLUTION: The dual frequency share dipole antenna consists of a first dipole antenna resonating in a first frequency f<SB>1</SB>and two dipole antennas each resonating in a second frequency f<SB>2</SB>(f<SB>2</SB>>f<SB>1</SB>) and disposed in a linear direction as a unit antenna constituting an array antenna device 51. (1) The one for vertical polarization feed power to the first dipole 12 at two points, and centrally feeds power to the two dipoles 13, 14, and (2) the one for horizontal polarization feeds power to the first and second dipole elements 22, 23 and 24 via a feeder circuit substrate 47 having a simple wave divider 47a at each center feeding point. A plurality of antenna devices for vertical polarization and a plurality of antenna devices for horizontal polarization are alternately disposed in a vertical direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna device used for a base station in a mobile communication system, for example, and more particularly to a dual-frequency dipole antenna device that requires shared characteristics in two frequency bands.
[0002]
[Prior art]
At present, this type of mobile communication system on land mainly uses IMT-2000 (International Mobile Telecommunications-2000) using 2 GHz band from PDC (Personal Digital Cellular) standard using 800 MHz band. In the transition period to the next generation mobile communication system standardized by ITU), the PDC system and the IMT-2000 system are used together in the base station. Therefore, from the viewpoint of cost reduction, there is a demand for a frequency sharing antenna device for the 800 MHz band and the 2 GHz band that can be used in combination with the PDC method and the IMT-2000 method.
[0003]
FIG. 14 is a schematic configuration diagram of a conventional dual-frequency vertically polarized array antenna apparatus used conventionally. The element of this dual-frequency vertically polarized array antenna 101 is a combination of the first dipole element 102 in the 800 MHz band and the second dipole element 103 in the 2 GHz band, and resonates in the 800 MHz band and the 2 GHz band. To do. (104 shown with a dashed-dotted line is a reflecting plate, which is arranged if necessary.)
The conventional dual-frequency dipole element referred to here is one in which the feeding points of each frequency band are on the same central axis. For example, it is a structure found in Patent Document 1 and the like.
[0004]
[Patent Document 1]
JP 2001-313516 A: Multi-frequency dipole antenna device
[0005]
A typical arrangement interval of the elements of the conventional dual-frequency vertically polarized array antenna 101 is about 150 mm as shown in FIG. 14, 0.44 wavelength for the 800 MHz band, and 1. for the 2 GHz band. This corresponds to 02 wavelength. The center frequency of the frequency band here is 885 MHz in the 800 MHz band and 2.045 GHz in the 2 GHz band.
[0006]
The element spacing of a normal array antenna is selected between approximately 0.5 to 0.9 wavelengths of the resonance frequency. The reason for this is that when the element spacing is shorter than 0.5 wavelength, the mutual coupling between the antenna elements increases, and the impedance of the antenna elements changes greatly or the directivity changes greatly. Further, when the element interval is longer than 0.9 wavelength, a grating lobe is generated.
[0007]
Therefore, when a conventional dual-frequency antenna element is used in frequency bands that are more than twice as far as the 800 MHz band and the 2 GHz band, the element spacing is inappropriate in each frequency band.
As a result, in the 800 MHz band, the VSWR is deteriorated due to the influence of mutual coupling between the antenna elements, and in the 2 GHz band, the gain is lowered and the gain fluctuation at the time of beam tilt is increased due to the generation of the grating lobe. There was an adverse effect.
[0008]
FIG. 15 shows an example of vertical plane directivity in the 2 GHz band when 18 elements of the dual-frequency vertically polarized array antenna 101 of FIG. 14 are arranged at intervals of 150 mm, and a large grating lobe in the sky direction. Is observed.
Furthermore, with the increase in subscribers due to the spread of mobile communications in recent years, further improvement in communication quality has been demanded, and a diversity reception system has been adopted in order to increase radio wave reception efficiency.
[0009]
[Problems to be solved by the invention]
However, from the viewpoint of saving space, the polarization diversity system that requires only one antenna is more effective than the space diversity system that requires two antennas.
Therefore, in addition to frequency sharing, there has been a problem that there is a very difficult request to combine antennas for polarization sharing into one.
[0010]
In the case of a single frequency, several antennas for both vertical polarization and horizontal polarization have been reported. For example, as shown in Patent Document 2, there is a polarization sharing array antenna in which each element is a dipole.
[0011]
[Patent Document 2]
JP 2000-091843 A: Dual-polarized antenna device
[0012]
In order to make this frequency sharing, it is conceivable to replace the respective dipole elements with the two-frequency sharing dipole elements 102 and 103 shown in FIG.
However, when this is arranged in the vertical direction, the element spacing must be selected so as to be appropriate in both the low frequency band and the high frequency band. However, as described above, these frequency bands are the 800 MHz band and the 2 GHz band. As described above, when the frequency band is twice or more apart, there arises a problem that the arrangement interval in the vertical direction must be inappropriate.
[0013]
Moreover, as an example of a non-directional antenna for both single-frequency vertical polarization and horizontal polarization, the one shown in Japanese Patent Application No. 2002-266959 already proposed by the present applicant is cited. Replacing with a frequency sharing dipole causes the same problems as described above.
In particular, in the case of this antenna, even if another method is to be applied due to the precise configuration, further modification is difficult, and it has been almost impossible to realize the antenna configuration.
[0014]
In the case of configuring an array antenna sharing a frequency more than twice as in the above-described 800 MHz band and 2 GHz band, if the conventional dual frequency shared element is used, an inappropriate element spacing is used in each frequency band. Thus, there is a problem that it is difficult to obtain a satisfactory vertical plane directivity.
This problem also occurs in the case of configuring a polarization sharing antenna that shares a frequency, and makes it difficult to realize the antenna. In the case of an omnidirectional antenna for both frequency sharing and polarization sharing, the same problem occurs as described above, and it has been almost impossible to realize the antenna.
[0015]
The present invention has been made in view of such a point, and the object thereof is to solve the above-mentioned problems, to improve the vertical plane directivity of a conventional array antenna for two frequencies, and to make a vertical polarization for two frequencies. A dual-frequency dipole antenna that can be applied to a shared antenna with horizontal polarization, and that can be omnidirectional in the horizontal plane by using both horizontal and vertical polarization for dual-frequency sharing, which was previously impossible to construct. To provide an apparatus.
[0016]
[Means for Solving the Problems]
The configuration of the dual-frequency dipole antenna device of the present invention to achieve the above object is to radiate radio waves polarized in the array direction as a unit antenna element constituting the array antenna device and share two frequency bands. Therefore, the first frequency f ₁ A first dipole element that resonates with the first dipole element and a second frequency f disposed in parallel with the first dipole element in front of the radio wave radiation direction. ₂ (F ₂ > F ₁ ) And the unit antenna element including two second dipole elements arranged in a linear direction, and feeding the first dipole element of the unit antenna element from two points, This is a dual-frequency dipole antenna device that feeds two second dipole elements from respective central feed points.
[0017]
As a unit antenna element constituting the array antenna device, a metal foil having an arbitrary width formed on the surface of the dielectric substrate in order to radiate radio waves polarized in the array direction and share two frequency bands, or 1st frequency f which consists of a metal flat plate with arbitrary width ₁ A metal foil having an arbitrary width formed on the surface of the dielectric substrate in parallel to the front of the first dipole element in the radio wave radiation direction, or an arbitrary width. A second frequency f made of a flat metal plate ₂ (F ₂ > F ₁ ) And the unit antenna element including two second dipole elements arranged in a linear direction, and feeding the first dipole element of the unit antenna element from two points, This is a dual-frequency dipole antenna device that feeds two second dipole elements from respective central feed points.
[0018]
As a unit antenna element constituting the array antenna device, it radiates a radio wave polarized in a direction orthogonal to the array direction and shares two frequency bands, so that it has an arbitrary width formed on the surface of the dielectric substrate. A first frequency f made of a metal foil or a metal flat plate having an arbitrary width ₁ A first dipole element that resonates with a metal foil having an arbitrary width formed on the surface of the dielectric substrate in parallel with an upper and lower direction or a front and rear direction of a radio wave emission direction of the first dipole element, or Second frequency f made of a metal flat plate having an arbitrary width ₂ (F ₂ > F ₁ The unit antenna element is composed of two second dipole elements that are arranged in a linear direction, and a feeder circuit board that feeds radiated power to the unit antenna element is the same as the array direction. The demultiplexing means is disposed on the power supply circuit board, the input side of the demultiplexing means is formed as one terminal, the output side is formed as three terminals, and each of the three terminals on the output side is formed. 1 terminal is connected to the central feeding point of the first dipole element, and the remaining two terminals are connected to the respective central feeding points of the second dipole element.
[0019]
In the dual-frequency dipole antenna device, a plurality of unit antenna elements are arranged in a linear direction to form an array antenna device.
[0020]
A plurality of the unit antenna elements according to claim 2 and a unit antenna element according to claim 3 are arranged in a plurality of vertical directions while the directions of the respective antenna elements are substantially perpendicular to each other. The unit antenna elements are alternately arranged to form an array antenna device, and the radio wave radiated as a whole is radiated so as to be vertically polarized and horizontally polarized.
[0021]
6. The dual-frequency dipole antenna device according to claim 5, wherein the reflecting plate is disposed on each plate surface of the rectangular cylindrical reflecting plate to form an array antenna device. This is a dual-frequency dipole antenna device capable of obtaining omnidirectional radiation characteristics.
[0022]
In the dual-frequency dipole antenna device of the present invention, one of the configurations for achieving the above object is as shown in FIG. 1, in which a first dipole fed at two points in the low frequency band of the ultra high frequency band is fed. This is an array antenna device in which a plurality of one unit antenna elements are arranged in the array direction, which is a combination of an element and two normal second dipole elements in a high frequency band.
[0023]
As the unit antenna element of one unit, as shown in FIG. 1, the power supply to the first dipole element in the 800 MHz band which is the low frequency band is about 100 mm centering on the mechanical center point of the dipole element. Two-point power feeding with two positions at two intervals is used, and 2 in the 2 GHz band which is the high frequency band in front of it (in the direction of radio wave radiation of the first dipole element and parallel to the first dipole element). Each of the second dipole elements is connected. The unit antenna elements are linearly arranged at intervals of about 200 mm, for example, in the vertical direction. As a result, the element spacing is 200 mm (0.59 wavelength) in the 800 MHz band and 100 mm (0.68 wavelength) in the 2 GHz band, which is an appropriate element spacing. That is, the element spacing of the array antenna device is selected between 0.5 and 0.9 wavelengths of the resonance frequency.
This configuration can be applied as, for example, a dual-frequency dipole antenna device for vertical polarization.
[0024]
As shown in FIG. 4, another configuration for achieving the above-described object is that a first antenna element in a low frequency band and a second antenna element 2 in a high frequency band in the ultra high frequency band. This is a two-frequency shared array antenna apparatus in which a plurality of one unit antenna elements are arranged in the array direction, in which a plurality of antenna elements are combined with a power feeding circuit for connecting the first and second antenna elements.
The power feeding circuit of the power feeding circuit board incorporates a simple duplexer as a demultiplexing means, the number of output terminals of the simple duplexer is 3, and one of the terminals is for the low frequency band, and the other two A terminal is used for a high frequency band, and the first and second antenna elements of the low frequency band and the high frequency band are connected to each terminal.
[0025]
The simple duplexer is connected to the high frequency band (2 GHz band) of the output terminals, and has two terminals with an interval of about 100 mm, and the low frequency band (800 MHz band) near the center. A unit composed of one terminal to be connected is defined as one unit, which is arranged at intervals of about 200 mm, for example, in the vertical direction.
[0026]
Single frequency antenna elements matching the respective frequencies are connected to the three terminals of the respective frequency bands on the output side of the simple duplexer. As a result, the antenna element spacing is approximately 200 mm (0.59 wavelength) in the 800 MHz band and approximately 100 mm (0.68 wavelength) in the 2 GHz band, which is an appropriate element spacing. That is, the element spacing of the array antenna device is selected between 0.5 and 0.9 wavelengths of the resonance frequency.
Since this configuration does not limit the antenna elements to be connected, it can be applied as a dual-frequency antenna for horizontal polarization and circular polarization in addition to vertical polarization.
[0027]
When two-frequency shared horizontally polarized wave and vertically polarized wave antenna devices are configured, one applies the antenna configuration of FIG. 1 as a vertically polarized wave element and the other as a horizontally polarized wave element. 4 is applied, and the antenna elements to be connected are horizontally polarized dipoles in the 800 MHz band and the 2 GHz band. Thereby, in each polarization element, the element spacing in the 800 MHz band and the 2 GHz band becomes appropriate, and the vertical plane directivity of both polarizations can be satisfied.
[0028]
Furthermore, even in the case of an omnidirectional antenna device for both dual-frequency horizontal polarization and vertical polarization, it can be realized by applying the configuration shown in FIGS.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail by way of example with reference to the drawings.
[0030]
[First embodiment]
2 and 3 show an embodiment of the dual-frequency dipole antenna device of the present invention, and the dual-polarization is performed in the first array direction based on the configuration of FIG. FIG. 2 is a diagram showing a first embodiment and a second embodiment of a dipole antenna device. FIG. 2 is a perspective view of a general type using a metal conductor as a unit antenna element, and FIG. 3 is a dielectric blind substrate. It is a front view of the mass-production type thing using the.
[0031]
The configuration of the dual-frequency dipole antenna device 1 shown in FIG. 2 shows the first embodiment, and the dual-frequency dipole antenna device 1 that is polarized in the first array direction, for example, for vertical polarization, In order to radiate radio waves polarized in the array direction and to share the two frequency bands, the unit antenna element constituting the array antenna apparatus is the first for the low frequency band (800 MHz band) of the ultra high frequency band. 1 dipole element 2 and two second dipole elements 3 and 4 for a high frequency band (2 GHz band). In addition, the reflecting plate 5 shown with a dashed-dotted line is arrange | positioned as needed.
The structure is such that the first dipole element 2 in the 800 MHz band is connected at two points 2a and 2b (2a, 2a, and 2b and 2b, respectively) via a feeder line 6 that is bifurcated at the feeding end on the input side. Further, the two second dipole elements 3 and 4 in the 2 GHz band, which are arranged in parallel to the first dipole element 2 at the front, that is, in front of the radio wave radiation direction, respectively. Connected and powered at the same time.
[0032]
The dipole antenna device 1 has directivity similar to that of a normal dipole with one point feeding in the 800 MHz band, and directivity when two normal dipoles are arranged in the 2 GHz band. Usually, each of the two feeder lines 6 branched into two has the same length, so that they are in phase at two feeding points. However, it is possible to intentionally change the length and add a phase difference. This indicates that the vertical plane directivity can cope with changing the beam direction, that is, the tilt angle.
[0033]
The structure of the dual-frequency dipole antenna device 11 shown in FIG. 3 is the same as that of the first embodiment. The structure of the dipole antenna device 1 shown in FIG. Metal foil having an arbitrary width (or a metal flat plate having an arbitrary width) formed on the surface of the body printed board 10 (one and the other of the respective radiating elements constituting the dipole are formed on each surface) And the first frequency f ₁ For example, the first dipole element 12 resonating in the 800 MHz band, and the surface of the dielectric printed circuit board 10 in front of the first dipole element 12 in the radio wave radiation direction and in parallel with the first dipole element 12 Is formed of a metal foil having an arbitrary width (or a metal flat plate having an arbitrary width), and has a second frequency f. ₂ (F ₂ > F ₁ For example, two second dipole elements 13 and 14 that resonate in the 2 GHz band and are arranged in a linear direction. In addition, the reflecting plate 15 shown with a dashed-dotted line is arrange | positioned as needed.
A solid line in FIG. 3 indicates a pattern on the front surface side of the dielectric printed circuit board 10, and a broken line indicates a pattern on the back surface side of the dielectric printed circuit board 10. Here, the feeder line 16 is a parallel strip line formed by the patterns on the front surface side and the back surface side.
[0034]
Further, a coupling portion 12c is formed in the central portion of the first dipole element 12 fed from the two points 12a and 12b in the 800 MHz band, and as shown in FIG. 3, the surface side of the dielectric printed circuit board 10 is formed. And the pattern on the back side can be overlapped, and can be selected from electromagnetic coupling or direct bonding short-circuited using a via hole or the like. Similarly to FIG. 2, the feeding phase can be changed by changing the length of the parallel strip line 16 branched into two.
[0035]
[Second Embodiment]
4 to 6 show a second embodiment of the dual-frequency dipole antenna device of the present invention, FIG. 4 is a diagram showing a schematic configuration of the dual-frequency antenna device of the present invention, and FIG. FIG. 6 is a diagram showing a configuration of a dual-frequency dipole antenna device that is polarized in a direction orthogonal to the second array direction, for example, for horizontally polarized waves, and FIG. 6 shows a pattern of a feeder circuit board for the feeder circuit of FIG. FIG.
[0036]
In FIG. 5, a dual-frequency dipole antenna device 21 that is polarized in a direction orthogonal to the second array direction, for example, a horizontally polarized dual-frequency dipole antenna device 21, In order to radiate and share the two frequency bands, the first dipole element 22 and the second dipole elements 23 and 24 as unit antenna elements constituting the array antenna apparatus, and the radiated power to the unit antenna elements And a power supply circuit board 27 for supplying the power.
[0037]
The unit antenna element has a first frequency f made of a metal foil having an arbitrary width or a metal flat plate having an arbitrary width formed on the surface of the dielectric printed circuit board 20a. ₁ The first dipole element 22 that resonates with the first dipole element 22 is arranged in parallel with the first dipole element 22 in the direction of radio wave radiation of the first dipole element 22 in FIG. A second metal foil having an arbitrary width or a metal flat plate having an arbitrary width formed on each surface of the two dielectric printed circuit boards 20b and 20c, which are arranged at a distance therebetween. Frequency f ₂ (F ₂ > F ₁ ) And two second dipole elements 23 and 24 arranged in the vertical direction.
[0038]
As shown in FIG. 5, the feeder circuit board 27 is arranged in the same direction as the array direction of the first and second dipole elements 22, 23, 24, and as shown in FIG. The substrate 27 is formed and disposed with a simple duplexer 27a on the dielectric printed circuit board 20d, and the input side of the simple duplexer 27a is formed with one terminal and the output side with three terminals. Of the three terminals, one terminal is connected to the central feeding point of the first dipole element 22, and the remaining two terminals are connected to the central feeding points of the second dipole elements 23 and 24. The feed circuit board 27 supplies radiated power to the first and second dipole elements 22, 23, and 24, respectively, and the radio waves horizontally polarized from the first and second dipole elements 22, 23, and 24. Is radiating.
[0039]
[Third embodiment]
FIG. 7 shows a second embodiment of the present invention, and is a perspective view of a dipole antenna (array antenna) device for dual frequency use, for example, for vertical polarization, based on the configuration shown in FIGS.
In FIG. 7, the dual-frequency dipole antenna device 31 includes a plurality (two in this embodiment) of the dual-frequency dipole antenna device 11 shown in FIG. 3 in the vertical direction of the array direction. The dipole antenna portion is formed by a combination of the one formed integrally with the dielectric printed circuit board 30 and the acute angle corner reflector 35. The dielectric printed circuit board 30 on which the dipole antenna portion is integrally formed is mounted on the acute angle bisector of the acute angle corner reflector 35. In addition, the same code | symbol is attached | subjected to the same member as the member in FIG. 3, and the description is abbreviate | omitted.
[0040]
The dipole antenna unit includes two sets of dipole elements each having the configuration shown in FIG. 3 and a combination of the first dipole 12 with two-point feeding in the 800 MHz band and the two second dipoles 13 and 14 in the 2 GHz band. Since they are arranged, two first dipoles 12 in the 800 MHz band and two second dipoles 13 and 14 in the 2 GHz band are arranged in total. Each dipole element is arranged at an appropriate element interval.
[0041]
In this example, directivity is given to the horizontal plane using the acute angle reflection plate 35, and the beam width can be changed depending on the angle and shape of the acute angle reflection plate 35.
Then, radiation power is supplied to the first and second dipole elements 12, 13, and 14, respectively, and vertically polarized radio waves are radiated from the first and second dipole elements 12, 13, and 14. .
[0042]
[Fourth embodiment]
8 and 9 show a dual-frequency dipole antenna (array antenna) device according to a fourth embodiment of the present invention. FIG. 8 shows the configuration of the antenna device 41 based on the configuration shown in FIG. FIG. 9 is a perspective view of the antenna (array antenna) device 41 for horizontal polarization, and FIG. 9 is a diagram showing a pattern of a power feeding circuit board 47 that forms the power feeding circuit of FIG.
[0043]
In FIG. 8, the dual-frequency dipole antenna device 41 includes a plurality (two in this embodiment) of the dual-frequency dipole antenna device 21 shown in FIG. 5 as unit antenna elements in a direction perpendicular to the array direction. A dipole antenna portion to be arranged is formed by a combination of an antenna connected to and formed on the feeder circuit board 47 arranged in the same direction as the array direction, and an acute angle corner reflector 45. The feeder circuit board 47, to which the dipole antenna portion is connected and integrally formed, is mounted on the acute angle bisector of the acute corner reflector 45. In addition, the same code | symbol is attached | subjected to the same member as the member in FIG. 5, and the description is abbreviate | omitted.
[0044]
The dipole antenna unit includes two sets of unit dipole elements each having the configuration shown in FIG. 5 and combining the first dipole 22 with central feeding in the 800 MHz band and the two second diballs 23 and 24 in the 2 GHz band. Since they are arranged in the vertical direction, two of the first dipoles 22 and four of the second dipoles 23 and 24 are arranged as a whole. Each dipole element is arranged at an appropriate element interval.
[0045]
FIG. 9 is a combination of two sets of the power supply circuit board 27 of FIG. 6 symmetrically.
As shown in FIG. 8, the feeder circuit board 47 in FIG. 9 is arranged in the same direction as the array direction of the first and second dipole elements 22, 23, and 24, and on the same dielectric printed board 40. Two simple demultiplexers 47a and 47b are formed and arranged on the input side, and each of the simple demultiplexers 47a and 47b is formed with one terminal on the input side and three terminals on the output side. Of the three terminals, one terminal is connected to the central feeding point of the first dipole element 22, and the remaining two terminals are connected to the central feeding points of the second dipole elements 23 and 24.
[0046]
The power supply circuit board 47 forms a power supply circuit using a microstrip line 48 formed on the surface of the dielectric printed circuit board 40. In FIG. 9, after two elements are distributed from the input side of one terminal by the number of microstrip lines 48, they are branched into three on the output side by the simple duplexers 47a and 47b. The simple duplexers 47a and 47b are filters that cut off a predetermined frequency by the demultiplexing stubs 47c, 47d, 47e, and 47f, and are simple.
[0047]
In addition, although the case where the feeder circuit board 47 is a two-element array is shown, the number of distributions can be changed according to the number of arrays. Further, the output to the 2 GHz band in the simple duplexers 47a and 47b is output in the same phase because the line length after the three branches is the same, but the phase can be changed by changing the line length.
Further, the power feeding circuit board shown in the power feeding circuit board 47 is basically not limited to the type of antenna device connected to the output side.
[0048]
Also in the present embodiment, the acute angle reflecting plate 45 is used to impart directivity to the horizontal plane, and the beam width can be changed depending on the angle and shape of the acute angle reflecting plate 45.
Then, radiated power is supplied to the first and second dipole elements 22, 23, and 24 via the feeder circuit board 47, and the horizontal power is supplied from the first and second dipole elements 22, 23, and 24. Polarized radio waves are radiated.
[0049]
[Fifth embodiment]
FIG. 10 shows a dual-frequency dual-pole dipole antenna (array antenna) device 51 for both horizontal and vertical polarizations, showing a fifth embodiment of the present invention. FIG.
This is based on the structure shown in Japanese Patent Laid-Open No. 2000-091843 shown in Patent Document 2 proposed by the present applicant, and is applied by combining the configurations shown in FIGS. In FIG. 10, only the main part of each of the dipole elements for horizontal and vertical polarization is shown, the feeding circuit section is omitted, and the Y-shaped horizontal polarization element shown in Patent Document 2 is a horizontal bar. It is replaced and displayed.
[0050]
In each vertical polarization element and horizontal polarization element of the dipole antenna device 51, there are two first dipoles 12 in the 800 MHz band, the two second dipoles 13 and 14 in the 2 GHz band, and 800 MHz. Two first dipoles 22 in the band and four of the two second dipoles 23 and 24 in the 2 GHz band are arranged, and the respective elements are arranged at appropriate element intervals.
The feeder circuit board 47 and the like may be configured at the rear portion of the planar reflecting plate 55, but may be formed integrally with the respective elements by a dielectric printed board as shown in FIGS.
[0051]
[Sixth embodiment]
FIG. 11 is a perspective view of an omnidirectional dipole antenna device 61 for dual frequency sharing and horizontal and vertical polarization sharing, showing a sixth embodiment of the present invention.
This is based on the structure of Japanese Patent Application No. 2002-266959 already proposed by the present applicant, and the configuration shown in FIGS. 7 and 8 is applied.
[0052]
In FIG. 11, each of the horizontal polarization element and the vertical polarization element is formed by arranging two 800 MHz band first dipoles and four 2 GHz band second dipoles in the vertical direction. There is a cylindrical reflector 65 made of a quadrangular prism or a substantially regular quadrangular prism metal material in the center, and a feeding circuit board made of a dielectric printed circuit board is attached to each surface of the cylindrical reflector 65. It is arranged. And it is formed in such a structure that the horizontal polarization dipole element and the vertical polarization dipole element surround the periphery. A feeding cable is disposed in the cylindrical reflecting plate 65, and is connected to a distributor below.
[0053]
Further, the structure will be described with reference to the detailed view of FIG. In FIG. 12, FIG. 12A is a block diagram, FIG. 12B is a detailed view of a vertical polarization power supply circuit section, and FIG. 12C is a detailed view of a horizontal polarization power supply circuit section. 12D is a diagram showing a 2 GHz band horizontal polarization dipole element in a section taken along the line dd in FIG. 12A, and FIG. 12E is taken along the line ee in FIG. 12A. It is a figure which shows the dipole element for 800 MHz band horizontal polarization in a cross section.
[0054]
The feeding circuit portion disposed so as to be attached to the cylindrical reflector 65 at the center of the dipole antenna device 61 is for vertical polarization as shown in FIGS. 12 (b) and 12 (c), respectively. There are two types, a power feeding circuit unit and a horizontally polarized power feeding circuit unit, each of which is provided with a total of four.
The vertical polarization power supply circuit unit is configured by a corporate (or tournament type) microstrip circuit, and the horizontal polarization power supply circuit unit is configured by a corporate type (or tournament type) microstrip circuit. Simple demultiplexers 48a and 47b are connected in the horizontal polarization feeding circuit board.
[0055]
A combination element of an 800 MHz band two-point feeding dipole and a 2 GHz band dipole is connected to the output end of the vertical polarization feeding circuit section. At that time, once on the vertical polarization element substrate in the horizontal direction, It connects to a combination element after passing through a two-branch circuit.
Accordingly, two combination dipole elements are connected to the output end of one vertical polarization feeding circuit section. Since the two feeding circuit portions form one set, four combination dipole elements are arranged so as to surround the cylindrical reflecting plate 65.
[0056]
There are two output ends of the horizontally polarized wave feeding circuit board 47 for the 800 MHz band and for the 2 GHz band through the simple duplexer 47a (or 47b). One 800 MHz band dipole is connected to the output terminal for the 800 MHz band, and two 2 GHz band dipoles are connected to the output terminal for the 2 GHz band through a two-branch circuit.
Since the two feeding circuit boards 47 form one set, two 800 MHz band dipoles and four 2 GHz band dipoles are arranged so as to surround the cylindrical reflector 65.
[0057]
Regarding the relationship between the arrangement positions of the vertically polarized dipole elements and the horizontally polarized dipole elements in the vertical direction, the 800 MHz band is alternately arranged, and the 2 GHz band is arranged in the same position. At this time, the dipole elements are combined without structurally interfering with each other. The vertical directivity of the vertically polarized dipole element in the 2 GHz band having such a structure is as shown in FIG. 13, and in particular, no grating globe is seen on the sky side.
In addition, this structure can be stacked in multiple stages, similar to the structure of Japanese Patent Application No. 2002-266959, and the vertical plane directivity tilt is obtained by collecting the feeding cables at the lowermost end and connecting a phase shifter. The angle can be controlled.
[0058]
As described above, as is clear from the description of each of the embodiments, according to the dipole antenna device for two frequencies, the two frequencies separated from the low frequency band, for example, 800 MHz band, and the high frequency band, for example, 2 GHz band. When a shared array antenna is configured, an appropriate element spacing is obtained in each frequency band, and satisfactory vertical plane directivity can be obtained.
[0059]
In the present embodiment, an example of a dual-frequency dipole antenna device for the 800 MHz band and the 2 GHz band has been described. However, by setting an appropriate element spacing, inter-element coupling becomes weak in the 800 MHz band, and VSWR deteriorates and directivity is increased. In the 2 GHz band, as shown in FIG. 13, the grating lobe does not occur, and the directivity is sufficiently satisfactory.
[0060]
This array method can also be applied to the construction of a dual-polarization dipole antenna that can be shared by two frequencies, and a horizontal plane that can be used for both horizontal polarization and vertical polarization. An omnidirectional antenna device can be obtained.
In the present embodiment, the dipole antenna device for a mobile communication system has been described with the frequency bands limited to the 800 MHz band and the 2 GHz band. However, the present invention is not limited to this, and is applicable to other communication systems and other frequency bands. Is possible.
[0061]
Note that the technology of the present invention is not limited to the technology in the above-described embodiment, and may be implemented by means of other modes that perform the same function, and the technology of the present invention may be variously modified within the scope of the above configuration. Addition is possible.
[0062]
【The invention's effect】
As is clear from the above description, according to the dual-frequency dipole antenna device of the present invention, as described in each of the claims, the vertical plane directivity for each frequency is improved and 2 It can be applied to a common antenna for both vertical and horizontal polarizations for each frequency, and horizontal and vertical polarization sharing for two frequencies, which has been impossible in the past. There is an excellent effect that can be obtained.
[0063]
Further, according to the present invention, the radiated power to be supplied to the respective dipole elements applied to the two respective frequencies can be supplied via the feeder circuit board, and the overall structure can be simplified. There is also an excellent effect.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a dual-frequency dipole antenna device of the present invention.
2 shows a first example 1 of the embodiment of the dual-frequency dipole antenna device according to the present invention, and shows a configuration of a vertically polarized dual-frequency dipole antenna device based on the configuration of FIG. It is a general type perspective view using a metal conductor as an antenna element.
FIG. 3 shows a first embodiment of the dual-frequency dipole antenna device according to the present invention, and shows a configuration of a vertically polarized two-frequency dipole antenna device based on the configuration of FIG. 1 as a unit antenna element; It is a front view of the mass-production type thing using the dielectric printed circuit board of this.
FIG. 4 is a diagram showing a schematic configuration of a two-frequency antenna apparatus of the present invention.
FIG. 5 is a diagram showing a configuration of a dual-polarization dipole antenna device for horizontal polarization based on the configuration of FIG. 4 according to the second embodiment of the present invention.
6 is a diagram showing a pattern of a power supply circuit board for the power supply circuit of FIG. 5. FIG.
7 is a diagram showing a third embodiment of the present invention, and is a perspective view of a vertically polarized dual-frequency dipole antenna device based on the configuration shown in FIGS. 1 and 3. FIG.
FIG. 8 is a diagram showing a fourth embodiment of the present invention, and is a perspective view of a dual-polarized dipole antenna device for horizontal polarization based on the configuration shown in FIGS. 4 and 5. FIG.
9 is a diagram showing a pattern of a power supply circuit board that forms the power supply circuit of FIG. 8. FIG.
FIG. 10 is a diagram showing a fifth embodiment of the present invention, and is a perspective view showing a main part of a two-frequency dipole antenna device for horizontal and vertical polarization and a flat reflector.
FIG. 11 is a diagram showing a sixth embodiment of the present invention, and is a perspective view of an omnidirectional dipole antenna device for two frequencies and for both horizontal and vertical polarization.
12 is a detailed diagram of the structure of the dual-frequency dipole antenna device of FIG. 11, in which FIG. 12 (a) is a block configuration diagram thereof, and FIG. 12 (b) is a detailed diagram of a vertically polarized wave feeding circuit unit; 12 (c) is a detailed view of the horizontal polarization feeding circuit section, FIG. 12 (d) is a diagram showing a 2 GHz band horizontal polarization dipole element in a section taken along line dd in FIG. 12 (a), and FIG. (E) is a figure which shows the dipole element for 800 MHz band horizontal polarization in the cross section by the ee line of Fig.12 (a).
13 is a view showing the vertical plane directivity of the vertically polarized dipole element in the high frequency band (2 GHz band) of the dual-frequency dipole antenna device of FIG. 12 (a).
FIG. 14 is a schematic block diagram of a conventional dual-frequency vertically polarized array antenna device.
15 is a diagram showing an example of vertical plane directivity in the 2 GHz band in a case where 18 elements are arranged at intervals of 150 mm in the two-frequency shared vertically polarized array antenna apparatus of FIG.
[Explanation of symbols]
1,11,21,31,41,51,61 Dual frequency dipole antenna device
2, 12, 22 First dipole element
2a, 2b, 12a, 12b Feeding point
3, 4, 13, 14, 23, 24 Second dipole element
5, 15, 35, 45, 55, 65 Reflector
6 Power supply line
10, 20a, 20b, 20c, 20d, 30, 40 Dielectric printed circuit board
12c joint
16, 48 microstrip line
27, 47 Feed circuit board
27a, 47a, 47b Simple duplexer
47c, 47d, 47e, 47f Stub

Claims (6)

As a unit antenna element constituting the array antenna apparatus, a first dipole element that resonates at a _first frequency f ₁ in order to radiate radio waves polarized in the array direction and to share two frequency bands; Two second dipole elements that are arranged in parallel with the second frequency f ₂ (f ₂ > f ₁ ) and are arranged in a straight line direction in parallel to the front of the radio wave radiation direction of one dipole element The unit antenna element comprising:
A dual-frequency dipole antenna device, wherein the first dipole element of the unit antenna element is fed from two points and the two second dipole elements are fed from respective central feed points. As a unit antenna element constituting the array antenna device, a metal foil having an arbitrary width formed on the surface of the dielectric substrate in order to radiate radio waves polarized in the array direction and share two frequency bands, or A first dipole element made of a metal flat plate having an arbitrary width and resonating at a _first frequency f ₁ is formed on the surface of the dielectric substrate in parallel with the front of the first dipole element in the radio wave radiation direction. Two second dipoles that resonate at a _second frequency f ₂ (f ₂ > f ₁ ) made of a metal foil having an arbitrary width or a metal flat plate having an arbitrary width and are arranged in a linear direction The unit antenna element comprising an element,
A dual-frequency dipole antenna device, wherein the first dipole element of the unit antenna element is fed from two points and the two second dipole elements are fed from respective central feed points. As a unit antenna element constituting the array antenna device, it radiates a radio wave polarized in a direction orthogonal to the array direction and shares two frequency bands, so that it has an arbitrary width formed on the surface of the dielectric substrate. A first dipole element that resonates at a _first frequency f _{1 made} of a metal foil or a metal flat plate having an arbitrary width, and parallel to the upper and lower sides or the front and rear direction of the radio wave radiation direction of the first dipole element, Resonates at a second frequency f ₂ (f ₂ > f ₁ ) made of a metal foil having an arbitrary width or a metal flat plate having an arbitrary width formed on the surface of the dielectric substrate, and is arranged in a linear direction. The unit antenna element comprising two second dipole elements,
The feeder circuit board that feeds radiated power to the unit antenna element is arranged in the same direction as the array direction, and a branching means is provided on the feeder circuit board, and the input side of the branching means has one terminal. In addition, the output side is formed of three terminals, one of the three terminals on the output side is a central feeding point of the first dipole element, and the remaining two terminals are each of the second dipole element. A dipole antenna device for dual-frequency use, wherein the dipole antenna device is connected to a central feed point. 4. The dual-frequency dipole antenna device according to claim 1, wherein an array antenna device is formed by arranging a plurality of the unit antenna elements in a linear direction. 5. A plurality of the unit antenna elements according to claim 2 and a unit antenna element according to claim 3 are arranged in a plurality of vertical directions while the directions of the respective antenna elements are substantially perpendicular to each other. A dual-frequency dipole characterized in that the unit antenna elements are alternately arranged to form an array antenna device, and radio waves radiated as a whole are radiated so as to be vertically polarized and horizontally polarized. Antenna device. 6. The dual-frequency dipole antenna device according to claim 5, wherein the reflecting plate is arranged on each plate surface of the rectangular cylindrical reflecting plate to form an array antenna device, and both horizontal and vertical polarized waves are shared. A non-directional radiation characteristic can be obtained.

Images