JP3990190B2 - Planar antenna device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a planar antenna device.
[0002]
[Prior art]
Planar antenna devices used for microwaves, millimeter waves, etc. are compatible with dielectric plates on one side (front) of a grounding conductor plate, a power supply substrate on which multiple radiating elements are formed, dielectric plates, and radiating elements In this structure, unnecessary radiation suppressing conductor plates, band adjusting elements and the like in which slots are formed are sequentially stacked.
[0003]
The radiating element of this planar antenna device is basically composed of a conductor so as to radiate a radio wave by resonating with a half wavelength of a transmission high-frequency signal.
[0004]
[Problems to be solved by the invention]
This type of planar antenna device uses a high-quality and expensive material for the dielectric plate in order to reduce loss and increase efficiency. Moreover, since it is necessary to position and laminate each plate-like body and element accurately, there is a problem that productivity is poor. Furthermore, a general planar antenna device is configured to efficiently adapt to one frequency band.
[0005]
Recently, there is an increasing demand for wireless communication systems using a plurality of frequency bands, and a plurality of antenna devices are required to meet such demand.
[0006]
However, if a plurality of antenna devices are installed, equipment costs are required. In order to reduce such equipment costs, it is desired that one planar antenna device can be efficiently applied to a plurality of frequency bands.
[0007]
Accordingly, one object of the present invention is to provide an efficient planar antenna device using an inexpensive material, and another object of the present invention is to improve the productivity of the planar antenna device. Still another object of the present invention is to provide a planar antenna device that can be efficiently applied to a plurality of frequency bands.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is a planar antenna device comprising a radiating element that radiates radio waves and a ground conductor plate that reflects radio waves radiated from the radiating elements. Is formed on one surface of the dielectric plate, and the dielectric plate is disposed so that the other surface of the dielectric plate is on the ground conductor plate side and a gap is formed between the dielectric plate and the ground conductor plate. The radiating element is integrally formed with a central conductor portion having a length of ½ wavelength of the first transmission high-frequency signal and on both sides of the central conductor portion so as to be self-symmetric with respect to the central conductor portion. A second conductor portion having a length of ½ wavelength of a second transmission high-frequency signal different from the formed first transmission high-frequency signal, and the first dielectric plate has a first conductor portion on one surface side of the dielectric plate . The first conductor plate having a length of ½ wavelength of the transmission high-frequency signal and both sides of the first conductor plate Band adjustment made of the second conductive plate of half the length of the wavelength of the first arranged separated independently from the conductive plate the said second transmission frequency signal symmetrically with respect to the first conductive plate The conductor element is disposed so as to face the radiating element.
[0010]
In the planar antenna device according to claim 2 , in addition to the configuration according to claim 1 , the dielectric plate and the radiating element are preferably formed by processing a single-sided printed wiring board.
[0012]
In the planar antenna device according to claim 3 , in addition to the configuration according to claim 1 or 2 , an unnecessary radiation suppressing conductor plate that suppresses unnecessary radio waves from the radiating element is arranged on one surface side of the dielectric plate. May be.
[0013]
According to a fourth aspect of the present invention, in addition to the configuration according to the third aspect, another dielectric plate on which the band adjusting conductor element and the unnecessary radiation suppressing conductor plate are formed is parallel to the dielectric plate. May be arranged.
[0014]
In the planar antenna device according to claim 5 , in addition to the configuration according to claim 4 , the band adjusting conductor element may be formed in the slot of the unnecessary radiation suppressing conductor plate.
[0015]
The planar antenna device according to claim 6 may include a plurality of radiating elements, band adjusting conductor elements, and slots in addition to the configuration according to any one of claims 1 to 5 .
[0016]
According to the present invention, the gap formed between the radiating element and the ground conductor plate is a free space having a dielectric constant of 1, and thus functions as a dielectric with little loss. Since this gap functions to control the dielectric constant between the ground conductor plate and the radiating element, the dielectric plate that supports the radiating element has a higher dielectric constant than the gap and is inexpensive and has a common printed wiring. A substrate can be used. The same applies to the case where a gap is formed between the radiating element and the band adjusting conductor element or the unnecessary radiation suppressing conductor plate. Since the radiating element, the band adjusting conductor element, and the unnecessary radiation suppressing conductor plate can be processed by etching the printed wiring board, a highly productive planar antenna device can be obtained.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0018]
FIG. 1 is an exploded perspective view of a planar antenna device of the present invention.
[0019]
The planar antenna device shown in FIG. 1 includes a ground conductor plate 4 and a plurality of radiating elements 2 (16 are shown but are not limited in the figure) connected in parallel by a feed wiring 2. The first dielectric plate 5 and the unnecessary radiation suppressing conductor having the band adjusting conductor element 3 in a plurality of slots 7a (16 is shown in the figure but the number is the same as the number of radiating elements). It is fixed by screws 9 and nuts 10 as coupling members and spacers 8a and 8b for forming gaps so that gaps are formed between the second dielectric plate 6 on which the plate 7 is formed. (The connecting member is not limited to the screw 9 and the nut 10 and may be a split pin or an adhesive).
[0020]
The ground conductor plate 4 is made of, for example, a silver-plated copper plate (or a metal plate such as a silver-plated copper plate or a rust-proof copper plate), and through-holes 4a through which screws 9 can pass are formed at four corners. Holes 4b are formed (the number of through holes 4a, screws 9 and nuts 10 is shown, but the number is not limited).
[0021]
The power supply wiring 2 and the radiation element 1 are formed on the surface of a first dielectric plate (for example, Teflon “registered trademark”) 5 by a printed wiring technique. That is, the power supply wiring 2 and the radiation element 1 can be obtained by etching the single-sided printed wiring board. At the four corners of the first dielectric plate 5, through holes 5a through which screws 9 can pass are formed.
[0022]
The band adjusting conductor element 3 and the slot 7a are formed on the surface of the second dielectric plate (for example, Teflon) 6 by a printed wiring technique. That is, the band adjusting conductor element 3 and the slot 7a are obtained by etching the single-sided printed wiring board. Through holes 6 a and 7 b through which screws 9 can pass are formed at the four corners of the second dielectric plate 6 and the unnecessary radiation suppressing conductor plate 7.
[0023]
Through holes 4a, 5a, 6a, 7b and spacers with spacers 8a, 8b interposed at the four corners of the ground conductor plate 4, the first dielectric plate 5, the second dielectric plate 6, and the unnecessary radiation suppressing conductor plate 7. A flat antenna device is obtained by passing a screw 9 so as to penetrate 8a and 8b, then connecting with a nut 10 and covering with a cover 11 made of a dielectric (eg, Teflon). The cover 11 is attached so as to contact the peripheral edge of the ground conductor plate 4 and prevent rainwater and the like from entering.
[0024]
Power supply from the outside to the power supply wiring 2 is performed by bringing the central conductor 12 a of the coaxial cable 12 penetrating the ground conductor plate 4 into contact with the power supply wiring 2.
[0025]
Between the grounding conductor plate 4 of this planar antenna device, the first single-sided printed wiring board (radiating element 1), and the second single-sided printed wiring board (unnecessary radiation suppressing conductive plate 7 and band adjusting conductor element 3). Since each formed void is a free space, it functions as a dielectric having a dielectric constant of 1 and low loss. The gap is formed between the ground conductor plate 4 and the radiating element 1, the radiating element 1, the unnecessary radiation suppressing conductor plate 7, and the band together with the dielectrics constituting the first single-sided printed wiring board and the second single-sided printed wiring board. It functions as a dielectric interposed between the adjustment conductor element 3.
[0026]
The dielectric constant between the ground conductor plate 4 and the radiating element 1 and between the radiating element 1 and the unnecessary radiation suppressing conductor plate 7 and the band adjusting conductor element 3 is dominated by the dielectric constant of the gaps interposed therebetween. Become. For this reason, the dielectric plates of the printed wiring board which are usually inexpensive and have a higher dielectric constant than the gap can be used for the first and second dielectric plates.
[0027]
According to such a planar antenna device, it is possible to efficiently adapt to two types of frequency bands and suppress emission of unnecessary radio waves. The radiating element, the band adjusting conductor element, and the unnecessary radiation suppressing conductor plate can be configured by etching the printed wiring board, and a highly productive planar antenna device can be obtained.
[0028]
Next, the radiation element will be described with reference to FIG.
[0029]
FIG. 2 is a plan view of a radiating element used in the planar antenna device shown in FIG.
[0030]
When the radiating element 1 is composed of a conductor plate (for example, a silver-plated copper plate or a gold-plated copper plate) so as to conform to two different frequency bands f1 (wavelength λ1) and f2 (wavelength λ2, where f1 <f2). I will explain it.
[0031]
The radiating element 1 has a strip-shaped central conductor portion 1a having a length (λ1 / 2) of ½ wavelength of the transmission high-frequency signal (frequency f1), 1 / of the frequency f2 different from the transmission high-frequency signal (f1). Two conductor portions 1b and 1c having a length of two wavelengths (λ2 / 2) are integrally formed so as to be self-symmetric. Between the conductor portions 1a, 1b, and 1c, slit-shaped notches 1d and 1e are formed along the longitudinal direction of the central conductor portion 1a in order to separate the high-frequency signals f1 and f2 well.
[0032]
When power is supplied to the radiating element 1 from the feeder wiring 2, the longer central conductor portion 1a of the radiating element 1 resonates with a signal in the lower frequency band f1 and radiates a radio wave in the lower frequency band (in a direction perpendicular to the paper surface). The shorter conductor portions 1b and 1c of the radiating element 1 resonate with a signal in the high frequency band f2 and radiate radio waves in the high frequency band.
[0033]
By constructing a planar antenna device using such a radiating element 1, radio waves in two frequency bands can be efficiently radiated from one planar antenna device.
[0034]
Next, the band adjusting conductor element will be described with reference to FIG.
[0035]
FIG. 3 is a plan view of a band adjusting conductor element used in the planar antenna apparatus shown in FIG.
[0036]
A case will be described where the band adjusting conductor element is formed of a conductor plate (for example, a silver-plated copper plate or a gold-plated copper plate) so as to conform to two different frequency bands f1 and f2.
[0037]
The band adjusting conductor element 3 is a strip-shaped conductor plate 3a having a length of ½ wavelength of the transmission high-frequency signal (f1), and is independently disposed on both sides of the conductor plate 3a, and 1 of the transmission high-frequency signal (f2). / Two strip-shaped conductor plates 3b and 3c each having a length of two wavelengths. The band adjusting conductor element 3 is disposed so as to face the radiating element 1.
[0038]
For this reason, the band adjusting conductor element 3 functions to widen the bandwidth of the frequency band f1 by the central conductor plate 3a acting strongly on the signal on the low frequency band f1 side, and the conductor plates 3b, 3c on both sides. Functions to widen the bandwidth of the frequency band f2 by strongly acting on the signal on the high frequency band f2 side. For this reason, by using such a band adjustment conductor element, the usable frequency bandwidth of the planar antenna device is widened.
[0039]
FIG. 4 is an exploded perspective view showing another embodiment of the planar antenna device of the present invention.
[0040]
This planar antenna device includes a plurality (16 in the figure) connected in parallel by the feed wiring 2 formed by the printed wiring technique on one surface (the upper side in the figure) of the ground conductor plate 4 and the first dielectric plate 5. The radiation element 1), an unnecessary radiation suppressing conductor plate 7 formed by printed wiring technology on one surface (the upper side in the figure) of the second dielectric plate 6, The band adjusting conductor element 3 formed by the printed wiring technique is superimposed on one surface (upper side in the figure) of the three dielectric plates 13 through spacers 8a, 8b, and 8c so that a gap is formed in sequence. And connected by a nut 10 and covered with a cover 11.
[0041]
The first dielectric plate 5, the power supply wiring 2, and the radiating element 1 are configured by an etching process using the first single-side printed wiring board, and the second dielectric plate 6 and the unnecessary radiation suppressing conductor plate 7 are The second single-sided printed wiring board is used for etching processing, and the third dielectric plate 13 and the band-adjusting conductor element 3 are configured by using a third single-sided printed wiring board for etching processing.
[0042]
Each radiating element 1 and the band adjusting conductor element 3 have the same configuration as that shown in FIGS.
[0043]
Power is supplied from the outside of the planar antenna device to the power supply wiring 2 by connecting the central conductor 12 a of the coaxial cable 12 penetrating the ground conductor plate 4 to the power supply wiring 2.
[0044]
According to this planar antenna device, the dielectric constant between the ground conductor plate 4 and the radiating element 1 and between the radiating element 1 and the unnecessary radiation suppressing conductor plate 7 and the band adjusting conductor element 3 is the gap interposed therebetween. Therefore, as the first to third dielectrics, a normal inexpensive printed wiring board dielectric can be used.
[0045]
A single planar antenna device can efficiently adapt to two types of frequency bands, suppress unnecessary radio wave radiation, and widen the frequency band. Since the radiating element 1, the feed wiring 2, the unnecessary radiation suppressing conductor plate 7, and the band adjusting conductor element 3 can be formed by etching using a single-sided printed wiring board, a planar antenna device with high productivity can be obtained. Can do.
[0046]
FIG. 5 is an exploded perspective view showing another embodiment of the planar antenna device of the present invention.
[0047]
This planar antenna device is formed by a printed wiring technique on one surface (upper side in the figure) of the ground conductor plate 4 and the first dielectric plate 5 and is connected in parallel by the feed wiring 2 (16 in the figure). The band adjusting conductor element 3 formed on one surface (the upper side in the figure) of the second dielectric plate 6 by a printed wiring technique, and the third dielectric plate. The unnecessary radiation suppressing conductor plate 7 formed by the printed wiring technique on one surface 13 is inserted through the spacers 8a, 8b, and 8c so that gaps are sequentially formed in the same manner as the planar antenna device shown in FIG. They are overlapped, joined by screws 9 and nuts 10 and covered with a cover 11.
[0048]
The first dielectric plate 5, the power supply wiring 2, and the radiating element 1 are configured by etching using a single-sided printed wiring board, and the second dielectric plate 6 and the band adjusting conductor element 3 are single-sided printed wiring boards. The third dielectric plate 13 and the unnecessary radiation suppressing conductor plate 7 are configured by etching the slot 7a using a single-side printed wiring board.
[0049]
Each radiating element 1 and the band adjusting conductor element 3 are the same as those shown in FIGS.
[0050]
Power is supplied to the power supply wiring 2 from the outside of the planar antenna device by connecting the central conductor 12 a of the coaxial cable 12 penetrating the ground conductor plate 4 to the power supply wiring 2.
[0051]
According to such a planar antenna device, the dielectric constant between the ground conductor plate 4, the radiating element 1, the band adjusting conductor element 3, and the unnecessary radiation suppressing conductor plate 7 is governed by the dielectric constant of the gap interposed therebetween. Therefore, the dielectric can be an ordinary inexpensive printed wiring board dielectric.
[0052]
As described above, it is possible to efficiently adapt to two types of frequency bands by using one planar antenna device, suppress the emission of unnecessary radio waves, and adjust the frequency band. Since all of the radiating element, the band adjusting conductor element, and the unnecessary radiation suppressing conductor plate can be configured by etching using a printed wiring board, productivity can be improved.
[0053]
【The invention's effect】
In short, according to the present invention, the following excellent effects are exhibited.
(1) An efficient planar antenna device can be provided using an inexpensive material.
(2) The productivity of the planar antenna device can be improved.
(3) A planar antenna device that can be efficiently applied to a plurality of frequency bands can be provided.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a planar antenna device of the present invention.
2 is a plan view of a radiating element used in the planar antenna device shown in FIG. 1. FIG.
3 is a plan view of a band adjusting conductor element used in the planar antenna device shown in FIG. 1. FIG.
FIG. 4 is an exploded perspective view showing another embodiment of the planar antenna device of the present invention.
FIG. 5 is an exploded perspective view showing another embodiment of the planar antenna device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Radiation element 2 Feeding wiring 3 Band adjustment conductor element 4 Ground conductor plate 5 1st dielectric board 6 2nd dielectric board 7 Unnecessary radiation suppression conductor board 7a Slot 8a, 8b, 8c Spacer 9 Screw 10 Nut 11 Cover 12 Coaxial cable 12a Center conductor 13 Third dielectric plate

Claims (6)

A radiating element that radiates radio waves;
In a planar antenna device provided with a ground conductor plate that reflects radio waves radiated from the radiating element,
The radiating element is formed on one surface of the dielectric plate;
The dielectric plate is disposed so that the other surface of the dielectric plate is on the ground conductor plate side and a gap is formed between the dielectric plate and the ground conductor plate.
The radiating element is integrally formed so as to be self-symmetric with respect to the central conductor portion on both sides of the central conductor portion and a central conductor portion having a length of ½ wavelength of the first transmission high-frequency signal. And a second conductor portion having a length of ½ wavelength of the second transmission high-frequency signal different from the first transmission high-frequency signal, and the first transmission on the one surface side of the dielectric plate A first conductor plate having a length of ½ wavelength of the high-frequency signal, and arranged on both sides of the first conductor plate so as to be separated from the first conductor plate symmetrically with respect to the first conductor plate A planar antenna device characterized in that a band adjusting conductor element made of a second conductor plate having a length of ½ wavelength of the second transmission high-frequency signal is arranged so as to face the radiation element. .   2. The planar antenna device according to claim 1, wherein the dielectric plate and the radiating element are obtained by processing a single-sided printed wiring board.   3. The planar antenna device according to claim 1, wherein an unnecessary radiation suppressing conductor plate that suppresses unnecessary radio waves from the radiating element is disposed on one surface side of the dielectric plate.   The planar antenna device according to claim 3, wherein another dielectric plate on which the band adjusting conductor element and the unnecessary radiation suppressing conductor plate are formed is disposed in parallel with the dielectric plate.   The planar antenna device according to claim 4, wherein the band adjusting conductor element is formed in a slot of the unnecessary radiation suppressing conductor plate.   6. The planar antenna device according to claim 1, comprising a plurality of the radiating elements, the band adjusting conductor elements, and the slots.

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