JP2008047964A - Antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antenna device that radiates vertical or horizontal polarized waves while sharing 1.7 GHz and 2 GHz frequency bands used in mobile communication, and reduces a wind pressure load while having power half value width narrower than a sector division angle. <P>SOLUTION: The antenna device 100 has: a first antenna element 10 that has a reflecting plate 15 for reflecting electric waves, and radiates the vertical polarized waves; a second antenna element 20 that has the reflecting plate 15 for reflecting the electric waves, and radiates the vertical polarized waves; and a synthesizer 30 for synthesizing an output signal from the first antenna element 10, and that from the second one 20. The first and second antenna elements 10, 20 are arranged so that the vibration directions of the vertical polarized waves to be radiated become nearly parallel mutually. Total width W1 of the first and second antenna elements 10, 20 arranged side by side ranges from not less than 140 mm to not more than 200 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antenna device, and more particularly, to an antenna device including two antenna elements.

  As a countermeasure against the increase in subscriber capacity of mobile communications in recent years, a 1.7 GHz band has been newly allocated in addition to a 2 GHz band which is a commonly used frequency band. For this reason, a telecommunications carrier providing mobile communication services needs to individually design and install not only an antenna device compatible with the 2 GHz band but also an antenna device compatible with the 1.7 GHz band. However, in urban areas where the subscriber capacity is relatively large, there is a background that the installation space of the antenna device is becoming tight, so a single antenna device that can handle both frequency bands described above can be used. The provision of

  In recent mobile communications, in general, radio waves are transmitted and received using a diversity effect by an antenna in order to ensure communication quality in a multi-wave propagation environment. In general, space diversity is used in which a diversity effect is obtained by installing two antennas as a single antenna device separated from each other by a predetermined distance. However, because of the background described above with respect to the installation space of the antenna device, polarization diversity that uses the difference in polarization plane between two orthogonal polarizations (generally vertical polarization and horizontal polarization) is used. Can be considered. In this case, a vertically polarized antenna and a horizontally polarized antenna are required. However, when these two antennas are orthogonal to each other to form a single antenna device, the antenna device has advantages over the space diversity described above. There is no. For this reason, it is desired to provide a vertical polarization antenna or a horizontal polarization antenna that can constitute an apparently dual polarization type antenna device that combines a vertical polarization antenna and a horizontal polarization antenna.

  Further, in DS-CDMA (Direct Spread Code Division Multiple Access) adopted for a radio access system in mobile communication, an antenna having a half-power width narrower than a sector division angle is required in order to increase the capacity of subscribers that can be supported. Use of the device is said to be effective. However, in order to narrow the half-power width, it is necessary to enlarge the aperture surface of the antenna. In order to increase the opening surface of the antenna, it is necessary to increase the area of the reflector, and as a result, there is a problem that the wind receiving area increases.

  Here, a building such as a building where the antenna device is installed usually has a load limit on the installation object, and even if the weight of the antenna device itself is within the limit, The wind pressure is applied in proportion to the size) and becomes heavier (this is called “wind pressure load”). For this reason, there is a problem that an antenna device having a relatively large wind pressure load may not be installed in a building.

In view of the above, an antenna device that has a half-power width narrower than the sector division angle and a small wind pressure load has been studied. For example, Patent Document 1 below discloses a multi-element array antenna that can reduce the wind receiving area and control the beam width. As shown in FIG. 1, the multi-element array antenna includes a first and second dipole antenna elements 1a and 1b, first and second reflectors 2a and 2b, and a combiner 3. This is a vertically polarized antenna in the 2 GHz band. Here, the first and second reflectors 2a and 2b are provided corresponding to the first and second dipole antenna elements 1a and 1b, respectively, and radiate from the corresponding dipole antenna elements 1a and 1b. Reflect the reflected beam. The combiner 3 combines the output signals from the first and second dipole antenna elements 1a and 1b. The interval between the dipole antenna elements is set to any value from 0.3 wavelength to 0.7 wavelength. With such a configuration, the wind pressure load is reduced while reducing the half-value width of power.
JP 2006-25247 A

  However, an antenna that radiates vertically or horizontally polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communications, and has a half-power width narrower than the sector division angle and a reduced wind pressure load. The device has not been fully studied.

  Therefore, the present invention has been made to solve the above problems, and radiates vertically or horizontally polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communications, An object of the present invention is to provide an antenna device that has a half-power width that is narrower than the sector division angle and has a reduced wind pressure load.

  As a result of intensive studies by the inventors to solve the above-described problems, the frequency is adjusted by adjusting the arrangement of two antenna elements having reflection means for reflecting radio waves and the width of the reflection means when arranged. It has been found that the wind pressure load can be reduced while sharing the band 1.7 GHz band and the 2 GHz band and having a power half width narrower than the sector division angle. The present invention has been made based on this finding.

  An antenna device according to the present invention includes a first antenna element that has first reflecting means for reflecting radio waves and radiates vertically polarized waves, and a second antenna that has second reflecting means for reflecting radio waves and radiates vertically polarized waves. An antenna element, and a combining means for combining the output signal from the first antenna element and the output signal from the second antenna element, wherein the first antenna element and the second antenna element are oscillated in the direction of vibration of the vertically polarized wave to be radiated Are arranged so as to be substantially parallel to each other, and the combined width of the first reflecting means and the second reflecting means arranged in a line is in the range of 140 mm or more and 200 mm or less.

  In the configuration of the antenna device according to the present invention, the first antenna element and the second antenna element are arranged side by side so that the vibration directions of vertically polarized waves radiated from the respective antenna elements are substantially parallel to each other. The combined width of the first reflecting means and the second reflecting means arranged in the range is from 140 mm to 200 mm. With this configuration, it is possible to radiate vertically polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communications. In addition, it has a power half width narrower than the sector division angle. Further, since the combined width of the first reflecting means and the second reflecting means is in the range of 140 mm or more and 200 mm or less, the wind pressure load can be reduced.

  An antenna device according to the present invention includes a first antenna element that has a first reflecting means for reflecting radio waves and radiates horizontal polarized waves, and a second reflecting means for reflecting radio waves and radiates horizontal polarized waves. A second antenna element; and a combining means for combining the output signal from the first antenna element and the output signal from the second antenna element, wherein the first antenna element and the second antenna element are configured to radiate horizontally polarized waves. The vibration direction is arranged so as to be substantially parallel to each other, and the combined width of the first reflecting means and the second reflecting means arranged in a line is in the range of 140 mm or more and 200 mm or less. .

  In the configuration of the antenna device according to the present invention, the first antenna element and the second antenna element are arranged side by side so that the vibration directions of the horizontally polarized waves radiated from the respective antenna elements are substantially parallel to each other. The combined width of the first reflecting means and the second reflecting means arranged in the range is from 140 mm to 200 mm. With this configuration, it is possible to radiate horizontally polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communication. In addition, it has a power half width narrower than the sector division angle. Further, since the combined width of the first reflecting means and the second reflecting means is in the range of 140 mm or more and 200 mm or less, the wind pressure load can be reduced.

  According to the present invention, while sharing the frequency band 1.7 GHz band and 2 GHz band used in mobile communication, radiation of vertically polarized waves or horizontally polarized waves is performed, and the wind pressure load has a power half width narrower than the sector division angle. It is possible to provide an antenna device with a reduced size.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same reference numerals are given to the same components in the drawings as much as possible, and duplicate descriptions are omitted.

(First embodiment)
First, the configuration of the antenna device 100 according to the first embodiment of the present invention will be described with reference to FIGS. 2 and 3. FIG. 2 is a perspective view illustrating a schematic configuration of the antenna device 100. 3A is a plan view illustrating a schematic configuration of one of the two antenna elements 10 and 20 included in the antenna device 100, and FIG. 3B is a front view illustrating the schematic configuration. The antenna device 100 is a two-element vertical polarization antenna device having a use frequency band of 1.7 GHz band and 2 GHz band, a substantially rectangular first antenna element 10 that radiates vertical polarization, and radiates vertical polarization. A substantially rectangular second antenna element 20 and a combiner 30 are provided.

  Each of the first antenna element 10 and the second antenna element 20 is arranged so that the long sides of substantially rectangular shapes are in contact with each other so that the vibration directions of the vertically polarized waves to be emitted are substantially parallel to each other. . That is, the first antenna element 10 and the second antenna element 20 have a positional relationship that is symmetrical with respect to the contact surface as a center of symmetry. The width of the entire device including the first antenna element 10 and the second antenna element 20 arranged in the horizontal direction (that is, the x direction shown in FIG. 2) so that the vibration directions are the same (that is, described later) Reflector width W1 is in the range from 140 mm to 200 mm. The combiner 30 is electrically connected to each of the first antenna element 10 and the second antenna element 20.

  Each of the 1st antenna element 10 and the 2nd antenna element 20 is comprised from the same component. Therefore, hereinafter, the configuration and function of the first antenna element 10 will be described as a representative. The first antenna element 10 is an element that radiates vertically polarized waves, and a conductor line 13 to be described later has a positional relationship perpendicular to the ground serving as a reference plane. As shown in FIG. 3, the first antenna element 10 includes a conductor substrate 11, a primary radiation element 12, a conductor line 13 as a feed line, a feed point 14, a reflector 15 as a reflector, and a parasitic element 16. is doing.

  The conductor substrate 11 is a rectangular substrate made of a conductor and is provided on the reflection plate 15. The width of the conductor substrate 11 is narrower than the wavelength of a radiated wave such as a vertically polarized wave radiated from the antenna element 10 described above.

  The primary radiating element 12 is a rectangular element that primarily emits a radiated wave, and is provided on the conductor substrate 11. The primary radiating element 12 is formed of an annular slot having a rectangular or oval shape whose peripheral length is the same as or slightly shorter than the wavelength of the radiated wave.

  The conductor line 13 is a line made of a conductor, and is provided on the conductor substrate 11 at a position between the conductor substrate 11 and the reflection plate 15. The conductor line 13 extends from the edge of the conductor substrate 11 to approximately the vicinity of the center of the primary radiation element 12.

  The feeding point 14 is a part that excites the primary radiation element 12 by electromagnetic coupling, and is provided on the conductor line 13.

  The reflection plate 15 is a plate-like device that reflects the beam emitted from the primary radiation element 12.

  The parasitic element 16 is an element that does not supply power, and is provided on the primary radiation element 12 at a position sandwiching the conductor line 13 together with the reflector 15. The parasitic element 16 is made of a rectangular or oval conductor whose peripheral length is the same as or slightly shorter than the wavelength of the radiated wave.

  The combiner 30 is a device that combines the first output signal from the first antenna element 10 and the second output signal from the second antenna element 20.

  In the antenna device 100 according to the present embodiment, by adjusting the above-described reflector width W1, it is possible to adjust and control the power half-value width of directivity in the horizontal plane. This is because the width of the reflection plate width W1 corresponds to the width of the opening portion of the antenna element, and the opening portion of the antenna element is widened by increasing the reflection plate width W1. FIG. 4 shows, as an example, a change in the half-value power width of the horizontal plane directivity when the above-described reflector width W1 is adjusted. As frequencies, for example, 1.7 GHz, which is the lower end frequency of the 1.7 GHz band, and 2.2 GHz, which is the upper end frequency of the 2 GHz band, are used. When 1.7 GHz is used as the frequency, by setting the reflector width W1 to a value in the range of 140 mm or more and 200 mm or less, the power half width of the directivity in the horizontal plane is from a value slightly lower than 60 degrees to about 45 degrees. Can be a value. In addition, this half value width of electric power can be made small, so that the reflector width W1 is enlarged. The power half width in this range is narrower than the sector division angle.

  In addition, when 2.2 GHz is used as the frequency, by setting the reflector width W1 to a value in the range of 140 mm or more and 200 mm or less, the power half-value width of the directivity in the horizontal plane is about 35 degrees from a value slightly lower than 50 degrees. The value can be up to. As the reflector width W1 is increased, this half-power width can be reduced. The power half width in this range is narrower than the sector division angle. From the above, in the region where the frequency bands of 1.7 GHz and 2 GHz are combined, the power half-value width of the directivity in the horizontal plane can be set to a value slightly lower than 60 degrees to about 35 degrees.

  Continuously, the effect of this embodiment is demonstrated. Each of the first antenna element 10 and the second antenna element 20 is arranged so that the vibration directions of the vertically polarized waves radiated from the respective antenna elements are substantially parallel to each other, and the reflections are arranged. The combined width of the plates 15 and 15 is in the range of 140 mm to 200 mm. With this configuration, it is possible to radiate vertically polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communications. Moreover, as shown in FIG. 4, it has a power half width narrower than the sector division angle. Furthermore, since the combined width of the reflectors 15 and 15 is in the range of 140 mm or more and 200 mm or less, the wind pressure load can be reduced.

(Second embodiment)
Next, the configuration of the antenna device 200 according to the second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a perspective view showing a schematic configuration of the antenna device 200. The antenna device 200 is a two-element horizontal polarization antenna device having a use frequency band of 1.7 GHz band and 2 GHz band, a substantially rectangular first antenna element 40 that radiates horizontal polarization, and radiates horizontal polarization. A substantially rectangular second antenna element 50 and a combiner 60 are provided.

  Each of the first antenna element 40 and the second antenna element 50 is arranged side by side with the substantially rectangular long sides in contact with each other so that the vibration directions of the horizontally polarized waves to be emitted are substantially parallel to each other. . In other words, the first antenna element 40 and the second antenna element 50 have a positional relationship that is symmetrical with respect to the contact surface as the center of symmetry. By arranging them symmetrically, the antenna elements 40 and 50 are excited with opposite phases to each other in order to achieve in-phase synthesis. The total width W2 of the device including the first antenna element 40 and the second antenna element 50 arranged in the horizontal direction (that is, the x direction shown in FIG. 2) so that the vibration directions are the same is 140 mm or more. It is in the range of 200 mm or less. The combiner 60 is electrically connected to each of the first antenna element 10 and the second antenna element 20.

  Since each of the first antenna element 40 and the second antenna element 50 is composed of the same constituent elements as in the first embodiment, description of each constituent element is omitted. The first antenna element 40 is an element that radiates horizontally polarized waves, and the conductor line 13 has a horizontal positional relationship with respect to the ground serving as a reference plane. Here, the first antenna element 40 and the second antenna element 50 are arranged in contact with each other so that the respective feeding points 14 of the first antenna element 40 and the second antenna element 50 are located at the approximate center of the antenna device 200. Has been placed. By arranging in this way, the space required for the feeding point 14 can be made compact.

  In the antenna device 200 of the present embodiment, by adjusting the width W2 of the entire device including the first antenna element 40 and the second antenna element 50, it is possible to adjust and control the FWHM of directivity in the horizontal plane. it can. FIG. 6 shows, as an example, a change in the half-value power of the horizontal plane directivity when the above-described reflector width W2 is adjusted. The frequencies used were 1.7 GHz, which is the lower end frequency of the 1.7 GHz band, and 2.2 GHz, which is the upper end frequency of the 2 GHz band. When a frequency of 1.7 GHz is used, by setting the reflector width W1 to a value in the range of 140 mm or more and 200 mm or less, the power half-value width of the directivity in the horizontal plane is a value from a value slightly lower than 60 degrees to about 45 degrees. Can be. In addition, this half value width of electric power can be made small, so that the reflector width W2 is enlarged. The power half width in this range is narrower than the sector division angle.

  Further, when the frequency of 2.2 GHz is used, by setting the reflector width W1 to a value in the range of 140 mm or more and 200 mm or less, the power half-value width of the directivity in the horizontal plane is set to a value from about 50 degrees to about 30 degrees. can do. As the reflector width W2 is increased, this half-power width can be reduced. The power half width in this range is narrower than the sector division angle. From the above, in the region where the frequency bands of 1.7 GHz and 2 GHz are combined, the power half-value width of the horizontal plane directivity can be set to a value slightly lower than 60 degrees to about 30 degrees.

  Continuously, the effect of this embodiment is demonstrated. The first antenna element 40 and the second antenna element 50 are arranged side by side so that the vibration directions of the horizontally polarized waves radiated from the respective antenna elements are substantially parallel to each other, and the reflections are arranged side by side. The combined width of the plates 15 and 15 is in the range of 140 mm to 200 mm. With this configuration, it is possible to radiate horizontally polarized waves while sharing the frequency bands 1.7 GHz and 2 GHz used in mobile communication. Moreover, as shown in FIG. 6, it has a power half-value width narrower than the sector division angle. Furthermore, since the combined width of the reflectors 15 and 15 is in the range of 140 mm or more and 200 mm or less, the wind pressure load can be reduced.

  As mentioned above, although this invention was concretely demonstrated based on 1st and 2nd embodiment, this invention is not limited to said embodiment, A various deformation | transformation is possible. It should be noted that those skilled in the art can develop the above embodiments and the following modifications without departing from the subject matter of the claims of the present invention. For example, the two-element vertical polarization antenna device 100 of the first embodiment and the two-element horizontal polarization antenna device 200 of the second embodiment are arranged in the vertical direction (that is, shown in FIG. 2) so that a predetermined gain is obtained. A plurality of multi-stage arrangements in the z direction) may be used, and a polarization sharing type antenna device that branches and excites from each parasitic element 16 may be configured. Thereby, it can be set as one antenna apparatus apparently.

It is a perspective view which shows schematic structure of the already disclosed antenna apparatus. It is a perspective view showing a schematic structure of an antenna device concerning a first embodiment of the present invention. It is the top view and front view of the antenna element of the antenna apparatus which concern on 1st embodiment of this invention. It is a graph which shows the relationship between the reflecting plate width | variety of the antenna apparatus which concerns on 1st embodiment of this invention, and the power half value width of directivity in a horizontal surface. It is a perspective view which shows schematic structure of the antenna device which concerns on 2nd embodiment of this invention. It is a graph which shows the relationship between the reflecting plate width | variety of the antenna apparatus which concerns on 2nd embodiment of this invention, and the power half value width of directivity in a horizontal surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b ... Dipole antenna element, 2a, 2b ... Reflector, 3, 30, 60 ... Synthesizer, 10, 40 ... First antenna element, 11 ... Conductor substrate, 12 ... Primary radiation element, 13 ... Conductor line, 14 DESCRIPTION OF SYMBOLS ... Feeding point, 15 ... Reflecting plate, 16 ... Parasitic element, 20, 50 ... Second antenna element, 100, 200 ... Antenna apparatus.

Claims (2)

A first antenna element having first reflecting means for reflecting radio waves and radiating vertically polarized waves;
A second antenna element having second reflecting means for reflecting radio waves and radiating vertically polarized waves;
Combining means for combining the output signal from the first antenna element and the output signal from the second antenna element;
The first antenna element and the second antenna element are arranged side by side so that the vibration directions of radiating vertically polarized waves are substantially parallel to each other,
The antenna device characterized in that the combined width of the first reflecting means and the second reflecting means arranged side by side is in a range of 140 mm to 200 mm. A first antenna element having first reflecting means for reflecting radio waves and radiating horizontal polarization;
A second antenna element having second reflecting means for reflecting radio waves and radiating horizontal polarization;
Combining means for combining the output signal from the first antenna element and the output signal from the second antenna element;
The first antenna element and the second antenna element are arranged side by side so that vibration directions of radiating horizontally polarized waves are substantially parallel to each other,
The antenna device characterized in that the combined width of the first reflecting means and the second reflecting means arranged side by side is in a range of 140 mm to 200 mm.

Images