JP2006108841A - Antenna assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a smaller antenna assembly in which one driven element can be used in two operating frequency bands in one 60° beam antenna assembly. <P>SOLUTION: In one 60° beam antenna assembly, antenna aperture width A at the distal end of a reflector 4 is set at 0.567λ, dipole antenna interval d<SB>H</SB>is set in the range of 0.53λ≤d<SB>H</SB>≤0.56λ, interval d<SB>V</SB>between a main reflector and a dipole antenna is set in the range of 0.20λ≥d<SB>V</SB>≥0.175λ, length L<SB>P</SB>of a parasitic element is set in the range of 0.30λ≤L<SB>P</SB>≤0.345λ, distance S<SB>1</SB>between the dipole antenna and the parasitic element is set in the range of 0λ≤S<SB>1</SB>≤0.066λ, and distance S<SB>2</SB>between the dipole antenna and the parasitic element is set in the range of 0.04λ≤S<SB>2</SB>≤0.056λ. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to, for example, a base station antenna that forms a 6-sector wireless zone in a mobile communication system, and relates to an antenna device that can be used in a 60 ° beam antenna device, particularly in two types of frequency bands.

Conventionally, in the third generation mobile communication system, a frequency of 2 GHz band is used, and a 6-sector wireless zone configuration with a base station antenna having a horizontal plane directivity of 60 ° is intended to cope with an increase in the number of subscribers. Employment has become mainstream. However, the number of subscribers is expected to increase further in the near future, and the use of new frequency bands such as the 800 MHz band and the 1.7 GHz band is under consideration. As the number of subscribers increases, sharing of the existing 2 GHz band and new frequency band is desired, and it is expected that the antenna to be used can also be handled with one antenna configuration.
Conventionally, as a method of supporting a plurality of use frequency bands with one antenna device, it has been common to provide an excitation element corresponding to each use frequency band. An example of the conventional multi-frequency shared antenna (Patent Document 1) is shown in FIG. FIG. 17a is a perspective view showing an example of a conventional multi-frequency shared antenna, and FIG. 17b is a plan view thereof. Side reflectors 20, 21 are provided to project vertically forward from both end edges of the vertical planar reflector 19, and are vertically extended first dipoles arranged in front of the reflector 19 and arranged in parallel with the reflector. antenna set 31a, 31b, 32a, 32b, 33a, 33b, 34a, 34b are successively arranged at regular intervals in a vertical direction, inside one another in a plane by a distance _{S 1} that includes a first dipole antenna, reflector from 19 to respective two points of distance _{S 2} from the first dipole antenna towards the first dipole antenna and the same direction, set 61a of the passive element, 61b, 62a, 62b, 63a , 63b, 64a, 64b , respectively The first dipole antenna is paired in the vertical direction. In the middle of the two first dipole antennas 31a and 31b forming a pair, a second extended from the reflector 19 to the same side as the first dipole antenna and extending up and down apart from the distance between the first dipole antenna and the reflector 19 Dipole antennas 41 and 42 are arranged. The conventional example shown in FIG. 17 is an example in which a plurality of antenna elements are arranged vertically to increase the antenna gain.

In FIG. 17, the first dipole antennas 31 a and 31 b and the parasitic elements 61 a and 61 b forming a pair are responsible for the high use frequency band, and the second dipole antennas 41 and 42 are responsible for the lower use frequency band. As described above, as a method of dealing with a plurality of use frequency bands with one antenna device, it is common to prepare a dedicated excitation element for each use frequency band.
Next, a conventional 60 ° beam antenna will be described (described in Non-Patent Document 1). FIG. 18 shows a conventional 60 ° beam antenna. 18a is a front view showing an example of a conventional 60 ° beam antenna, FIG. 18b is a plan view, and FIG. 18c is a side view. A reflector 80 comprising a main reflector 70 disposed in the vertical direction, a first side reflector 71 and a second side reflector 72 bent forward from both side edges of the main reflector 70, and the reflector 80 The first dipole antenna 74 and the second dipole antenna 75 are arranged in front of each other and arranged in parallel with the reflector, and extend in the opposite direction to the reflector 80 of the first and second dipole antennas 74 and 75, respectively. A first parasitic element 76 and a second parasitic element 77 are arranged. The first dipole antenna 74 and the second dipole antenna 75 are fed with high frequency signals of the same homogenous frequency from their feed points 78.

  Usually, the first and second dipole antennas 74 and 75 are located at a position of λ / 4 of the wavelength λ of the operating frequency band from the main reflector 70, and the distance between the first dipole antenna 74 and the second dipole antenna 75 is λ. It is arranged at the position of / 2. In addition, the antenna aperture width A formed at both end edges of the reflecting plate 80 is normally set to 0.67λ, and the directivity in the horizontal plane is set to 60 ° by the first and second parasitic elements 77. When the operating frequency is 2 GHz, the antenna aperture width A is set to 100 mm. For example, when considering using 1.7 GHz as a new use frequency, in the conventional design method, the antenna apparatus shown in FIG. 18 has a frequency other than the use frequency of 2 GHz, that is, one dipole antenna and 1 GHz. When considering use in the 7 GHz band, the antenna aperture width A is 118 mm, and the aperture width A is 18 mm larger. Therefore, the antenna inner diameter is also increased. The 3rd generation mobile communication service in the 2 GHz band has been started, and when starting the service at the new frequency, the existing antenna and the new frequency band shared antenna must be replaced. The installation space will also need to be changed. Naturally, the antenna effective lengths of the first and second dipole antennas 74 and 75 and the sizes of the first and second parasitic elements 76 and 77 also change in accordance with the used frequency band.

Therefore, in a 60 ° beam antenna apparatus as shown in FIG. 18, when a new use frequency is added in accordance with the increase in subscribers, it is necessary to newly install an antenna apparatus having a different shape. This is very uneconomical and there is a strong demand for a single antenna device.
JP 2000-174549 (paragraph 0005, FIG. 3) IEICE Transactions 2003 / 6Vol.J86-BNo.6 (952 to 953, 956)

In order to cope with a plurality of operating frequencies, an existing antenna device must be provided with an excitation element of a new frequency band. When two frequency bands are shared with respect to one excitation element, the frequency characteristics of the directivity in the horizontal plane of each frequency band And the service area in the frequency band is different. On the other hand, in order to be able to use it in a new frequency band in the same service area, it is necessary to increase the overall shape, and it is necessary to change the wind pressure load, the mounting function on the tower, the installation space, etc. was there.
The present invention has been made in view of these points, and can be used in two operating frequency bands using one excitation element in one 60 ° beam antenna apparatus, and has the same size as an existing one. An object of the present invention is to provide an antenna device that can be used.

In the present invention, the reflector, the first and second dipole antennas arranged in front of the reflector and parallel to the reflector, and the first and second parasitic elements in front of the first and second dipole antennas The reflector includes a rectangular flat main reflector and first and second side reflectors bent forward from both side edges of the main reflector,
The first and second dipole antennas are parallel to the folding lines of the main reflector and the first and second side reflectors, respectively, and the main reflector and the distance d _V , and between the first dipole antenna and the second dipole antenna. interval are opposed while maintaining a d _H, first and second parasitic elements, for each first and second dipole antennas, just inside the main reflector parallel to the distance S _1, and a main reflector opposite is arranged at a distance S ₂ in the direction, the first and second dipole antenna is provided with a single feeding point for the lower frequency signal and the first usable frequency band of the first usable frequency band second high-frequency signal, a first And the effective length of the second dipole antenna is ½ of the wavelength λ of the second high-frequency signal, and the distance d _V is smaller than ¼ of the wavelength, and the distance d _H Is 1 / of the above wavelength λ It was it is greater than the distance.

  As described above, in the case of the present invention, the effective antenna length of the first and second dipole antennas is 1 / 2λ of the wavelength λ of the low use frequency band, and the distance between the first and second dipole antennas is 1 / 2λ. And the interval between the reflector and the dipole antenna is smaller than 1 / 4λ, and the parasitic element is made to resonate in a high frequency band, and the interval is larger than the interval between the first and second dipole antennas. By making it narrow, it is possible to share the two used frequency bands with a pair of dipole antennas and without changing the antenna aperture width of the existing 60 ° beam antenna.

  When a new frequency band can be added without changing the antenna aperture width, it is not necessary to respond to the wind pressure load of the antenna and review the strength of the steel tower, as well as to use the radome and the installation space. Can be expected.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic diagram showing a basic configuration of an antenna apparatus according to the present invention. FIG. 1a is a perspective view thereof. A first dipole antenna 5 and a second dipole antenna 6 arranged in front of the main reflector 1 and arranged in parallel with the main reflector 1, and a first parasitic power in front of the first and second dipole antennas 5 and 6. An element 7 and a second parasitic element 8 are provided. The main reflector 1 is a rectangular flat plate, and a first side reflector 2 and a second side reflector that are integrally bent forward from both side edges of the main reflector 1. The reflector 3 is composed of the plate 3. First and second dipole antennas 5, 6 in parallel the main reflector 1 and the first and bending line of the second side reflectors 2 and 3, respectively, to face while keeping the main reflector 1 and the distance d _V Yes. The distance between the first dipole antenna 5 and the second dipole antenna 6 is opposed to each other while maintaining the distance d _H , and the first and second parasitic elements 7 and 8 are respectively connected to the first and second dipole antennas 5 and 6. , the distance S ₁ on the opposite side of the first and second side reflectors 2 and _3, is disposed at a distance S ₂ on the opposite side and the main reflector 1, first and second dipole antennas 5 and 6 And a single feeding point 9 for the high-frequency signal of the first use frequency and the second high-frequency signal lower than the first use frequency.

In this embodiment, a vertically polarized antenna device is used, the reflecting plate 4 is provided vertically, and the first and second dipole antennas 5 and 6 are also arranged vertically. The antenna aperture width A formed at the tip of the reflector 4 is 0.567λ, the dipole antenna interval d _H is within the range of 0.53λ ≦ d _H ≦ 0.56λ, and the interval d _V between the main reflector and the dipole antenna is Within the range of 0.20λ ≧ d _V ≧ 0.175λ, the length L _P of the parasitic element is within the range of 0.30λ ≦ L _P ≦ 0.345λ, and the distance S ₁ between the dipole antenna and the parasitic element Is within the range of 0λ ≦ S ₁ ≦ 0.066λ, and the distance S ₂ between the dipole antenna and the parasitic element is within the range of 0.04λ ≦ S ₂ ≦ 0.056λ, from the end of the main reflector 1 to the dipole. Assuming that the angle θ between the perpendicular to the antenna and the first and second side reflectors is 0 °, the length W of the side radiation plate in the bending extension direction is in the range of 0.056λ ≦ W ≦ 0.141λ. It was inside. Here, λ is the frequency of the second high-frequency signal (lower high-frequency signal), for example, a wavelength of 1.7 GHz. The frequency of the first high-frequency signal that is higher than the second high-frequency signal is, for example, 2 GHz.

The following explains that the above numerical values are optimal. FIG. 2 shows the relationship between the antenna aperture width A and the horizontal plane directivity. The horizontal axis represents the antenna aperture width as a converted value of the wavelength λ of 1.7 GHz, and the vertical axis represents the horizontal plane directivity as deg. The antenna aperture width A of the existing 2 GHz 60 ° beam antenna is 0.67λ _2G and 100 mm (converted value at 2 GHz). When this 100 mm is converted to a wavelength λ of 1.7 GHz, 0.567λ is obtained. Therefore, in order to share the existing 2 GHz 60 ° beam antenna and the 1.7 GHz 60 ° beam antenna, it is necessary to realize a horizontal plane directivity of 60 ° with an antenna aperture width A of 0.567λ. Therefore, in this embodiment, a method different from the conventional design method is used. That is, the first and second dipole antennas 5 and 6 (hereinafter abbreviated as dipole antennas 5 and 6) are resonated in the 1.7 GHz band, and the first and second parasitic elements 7 and 8 (hereinafter referred to as parasitic elements 7 and 8). Is abbreviated in the 2.0 GHz band.

0.4λ dipole antenna spacing _{d H,} 0.5 [lambda, and 0.51λ, 0.52λ, 0.53λ, 0.54λ, 0.55λ, the 0.56λ and parameters, dipole antenna aperture width A = 0. When the dipole antenna interval d _{H at} which the directivity in the horizontal plane is 60 ° or less at 567λ is obtained, the dipole antenna interval d _H is in the range of 0.53λ to 0.56λ.
FIG. 3 shows the same characteristics as FIG. 2 at 2 GHz. When the dipole antenna interval d _H = 0.4λ, the horizontal plane directivity is 60 ° or more, but when the dipole antenna interval d _H is 0.5λ or more, the horizontal plane directivity is as narrow as 55 ° or less. As for the directivity in the horizontal plane being smaller than 60 °, it has been reported that when the angle is smaller than 60 °, interference with other adjacent sectors decreases, and the communication capacity increases in the latter half of 40 °. (1999 Telecommunications Information Society General Conference B-5-157: Optimizing the beam width of the sector antenna in the W-CDMA system) Therefore, there is no problem if the directivity is 45 ° or more. It can be seen that the antenna distance d _H should be in the range of 0.53λ to 0.56λ. The dipole antenna interval d _H shown in this embodiment is greatly different from the value shown in Patent Document 1 described in the background art, and is thus set to a value larger than 0.5λ.

Then determine the optimum value of the vertical distance d _V between the dipole antenna 5, 6 and the reflector 4. Figure 4 shows the relationship between the dipole antenna 5, 6 and the vertical distance d _V and horizontal plane directivity of the reflector 4. The horizontal axis represents the vertical distance in terms of wavelength λ, and the vertical axis represents the horizontal plane directivity in deg. Horizontal Pattern relative vertical distance d _V shows the flat characteristic does not change greatly. In order to make the distance between the dipole antennas less than 60 ° directivity at a frequency of 1.7 GHz and the directivity in a horizontal plane within 60 °, the vertical distance d _V between the dipole antennas 5 and 6 and the reflector 4 is It is necessary to make the range 0.20λ ≧ d _V ≧ 0.175λ. The directivity in the horizontal plane at a frequency of 2.0 GHz is within the range of no problem from 48 ° to 51 ° in the horizontal plane when the vertical distance d _V is in the range of 0.175λ to 0.20λ.

Next, the optimum value of the length L _P of the parasitic elements 7 and 8 is obtained. FIG. 5 shows the relationship between the length L _{P of the} parasitic element and the return loss, and FIG. 6 shows the relationship between the length L _{P of the} parasitic element and the directivity in the horizontal plane. The horizontal axis in FIG. 5 represents the length L _P of the parasitic element in terms of wavelength λ, and the vertical axis represents the return loss in dB. Since the parasitic elements 7 and 8 are made to resonate at a frequency of 2.0 GHz, there is little change in the return loss at the frequency of 1.7 GHz. When the length L _P is larger than 0.345λ, the return loss becomes larger than −10 dB. With respect to the frequency of 2.0 GHz, a downwardly convex characteristic is shown, and the return loss is −10 dB or less when the parasitic element length L _P is in the range of 0.285λ to 0.358λ. Therefore, in order for the return loss to be −10 dB or less, the length L _P of the parasitic elements 7 and 8 needs to be in the range of 0.285λ ≦ L _P ≦ 0.345λ. The horizontal axis of FIG. 6 represents the length L _P of the parasitic element in terms of wavelength λ, and the vertical axis represents the horizontal plane directivity in deg. The horizontal plane directivity exhibits a flat characteristic with respect to the length L _{P of the} parasitic element. In order to reduce the directivity in the horizontal plane to 60 ° or less from FIG. 6 under the condition of frequency 1.7 GHz and dipole antenna interval d _H = 0.53λ, The length L _P of the elements 7 and 8 needs to satisfy L _P ≧ 0.3λ. From FIGS. 5 and 6, it is necessary to set the length L _P of the parasitic elements 7 and 8 within the range of 0.30λ ≦ L _P ≦ 0.345λ.

Next, the optimum value of the horizontal distance S ₁ between the dipole antennas 5 and 6 and the parasitic elements 7 and 8 is obtained. In determining the horizontal distance S ₁ , the difference in directivity in the horizontal plane between the frequency bands to be used becomes a problem, and the smaller the difference, the better. That is, if the use frequency band changes and the horizontal plane directivity changes greatly, an event occurs in which the service area is different for each frequency band. Therefore, as described in the above-mentioned reports, the directivity in the horizontal plane needs to be within about 45 ° to within 60 ° even if the used frequency band changes. When one reflector is shared by two frequency bands as in this embodiment, the directivity in the horizontal plane of the low use frequency band is widened, so the directivity in the horizontal plane of the low use frequency band is 60 ° or less, The directivity in the horizontal plane of the high frequency band is set to 45 ° or more. FIG. 7 shows the horizontal distance S ₁ between the dipole antenna and the parasitic element and the difference in directivity in the horizontal plane between the used frequency bands. The horizontal axis represents the distance S ₁ in the horizontal direction in terms of the wavelength lambda, and the vertical axis represents the case of this example, the difference between the horizontal plane directivity of the 1.7GHz and 2.0GHz (the deviation) in deg..

When the horizontal distance S ₁ is increased from 0, the deviation in directivity in the horizontal plane gradually decreases, the distance S ₁ becomes minimum at about 0.06, and then increases slightly as S ₁ increases. Indicates. FIG. 8 shows the relationship between the distance S ₁ and the return loss. The relationship between the horizontal distance S _{1 in the} frequency band 1.7 GHz and the return loss shows a characteristic that the return loss gradually decreases as S ₁ increases. This indicates that the return loss increases as the parasitic elements 7 and 8 are affected by the dipole antennas 5 and 6. For the frequency band 2.0 GHz, S ₁ is 0, and the return loss is the smallest, and the return loss increases as the parasitic elements 7 and 8 move away from the dipole antennas 5 and 6. This is because the parasitic elements 7 and 8 are resonated at 2.0 GHz. As a matter of course, the closer the parasitic elements 7 and 8 are to the dipole antennas 5 and 6, the more efficiently the power is transmitted. It is. Thus, it can be seen that the return loss is -10 dB or less when S ₁ is in the range of 0λ ≦ S ₁ ≦ 0.066λ.

Next, the optimum value of the vertical distance S ₂ between the dipole antennas 5 and 6 and the parasitic elements 7 and 8 is obtained. FIG. 9 shows the relationship between the vertical distance S ₂ between the dipole antennas 5 and 6 and the parasitic elements 7 and 8 and the return loss. The horizontal axis represents the vertical distance S ₂ in terms of wavelength lambda, the vertical axis represents the return loss in dB. In the frequency band of 1.7 GHz, S ₂ is about 0.04λ and the return loss is about −10 dB, which is the largest characteristic. At a frequency of 2.0 GHz, S ₂ is about 0.04λ and the return loss is minimized, and when S ₂ is 0.056 or more, the return loss is larger than −10 dB. Figure 10 shows the relationship between the vertical distance S ₂ and Horizontal Pattern. The sensitivity of the vertical interval S ₂ with respect to the directivity in the horizontal plane is low, and shows a substantially flat characteristic with respect to S ₂ . When the vertical distance S ₂ is 0.04λ or less, the directivity in the horizontal plane exceeds 60 ° in the frequency band 1.7 GHz. Therefore, from FIGS. 9 and 10, the vertical distance S ₂ between the dipole antennas 5 and 6 and the parasitic elements 7 and 8 needs to be in the range of 0.04λ ≦ S ₂ ≦ 0.056λ. The distance S ₂ shown in this embodiment is set to a small value significantly different from the distance shown in Patent Document 1 described in the background art.

Next, the optimum value of the angle θ formed by the length W of the side reflectors 2 and 3 and the perpendicular from the both end edges of the side reflectors 2 and 3 and the main reflector 1 to the dipole antenna is obtained. Table 1 shows a combination of the angle θ and the length W using the dipole antenna interval d _H as a parameter, where the directivity in the horizontal plane is within 60 ° and the return loss is −10 dB or less.

ダイポールアンテナ５，６の間隔ｄ_Ｈがｄ_Ｈ＝０．５３λ、角度θが０°では、Ｗが０.１４１λから０.１７λの範囲で水平面内指向性が６０°以内で且つ反射減衰量が−１０ｄＢ以下になる（以下、水平面内指向性が６０°以内で且つ反射減衰量が−１０ｄＢ以下をアンテナ仕様と略す）。角度θが５°ではＷが０.１１３λの長さ、角度θが１０°では同じくＷが０.１１３λの長さでアンテナ仕様を満足する。

When the distance d _H between the dipole antennas 5 and 6 is d _H = 0.53λ and the angle θ is 0 °, the directivity in the horizontal plane is within 60 ° and the return loss is in the range of W from 0.141λ to 0.17λ. −10 dB or less (hereinafter, the horizontal plane directivity is within 60 ° and the return loss is −10 dB or less is abbreviated as an antenna specification). When the angle θ is 5 °, W is 0.113λ, and when the angle θ is 10 °, W is also 0.113λ, which satisfies the antenna specifications.

When the distance d _H between the dipole antennas 5 and 6 is d _H = 0.54λ, and the angle θ is 0 °, W is in the range of 0.056λ to 0.141λ, and when the angle θ is 5 °, W is 0.056λ to 0. Satisfy antenna specifications in the range of .141λ. When the angle θ is 10 °, the length of W is 0.056λ, which satisfies the antenna specifications.
When the distance d _H between the dipole antennas 5 and 6 is d _H = 0.55λ and the angle θ is 0 °, the antenna specifications are satisfied within the range of W from 0.056λ to 0.17λ. When the angle θ is 5 °, W is 0.056λ, which satisfies the antenna specifications.

When the distance d _H between the dipole antennas 5 and 6 is d _H = 0.56λ and the angle θ is 0 °, the antenna specifications are satisfied only when W is in the range of 0.056λ to 0.17λ.
From the above results, when the respective continuous ranges where the directivity in the horizontal plane is within 60 ° and the return loss is −10 dB or less are obtained, the dipole antenna interval d _H is 0.54λ under the condition that the angle θ is 0 °. To 0.56λ, and the length W of the side reflectors 2 and 3 is in the range of 0.056λ to 0.141λ. Other than this, as described above, at the dipole antenna interval d _H = 0.53λ, the angle θ is 5 ° and the length W is 0.113λ, and the angle θ is 10 ° and the length W is 0.113λ. Satisfy the antenna specifications under certain conditions. Further, at the dipole antenna interval d _H = 0.54λ, the antenna specification is satisfied when the angle θ is 5 ° and the length W is in the range of 0.056λ to 0.141λ. Further, the antenna specification is satisfied with an angle θ = 10 ° and a length W = 0.056λ. Further, at the dipole antenna interval d _H = 0.55λ, the antenna specification is satisfied under the condition that the angle θ = 5 ° and the length W is 0.056λ.

From the results of the studies described above, as a preferred example, the antenna aperture width A is set to 0.567λ, the distance d _H = 0.53λ between the dipole antennas 5 and 6, and the horizontal distance S ₁ between the dipole antenna and the parasitic element. = 0.025λ, the length W of the side reflectors 2 and 3 is 0.11λ, and the angle θ is 10 °. FIG. 11 shows the frequency characteristics of the return loss of the antenna device under these conditions, FIG. 12 shows the directivity pattern at the use frequency of 1.7 GHz, and FIG. 13 shows the directivity pattern at the use frequency of 2.0 GHz.
In FIG. 11, the horizontal axis represents frequency and the vertical axis represents the return loss dB. Bands are secured in each of the 1.7 GHz band and the 2.0 GHz band. The interval between concentric circles representing the radiation levels in FIGS. 12 and 13 is 5 dB. A horizontal plane directivity of about 60 ° is realized at a use frequency of 1.7 GHz and an antenna aperture width A = 0.567λ. In addition, the directivity in the horizontal plane of about 52 ° is realized even at a use frequency of 2.0 GHz.

As described above, the antenna effective length of the dipole antennas 5 and 6 is set to 1 / 2λ of the wavelength λ in the low use frequency band, the interval between the dipole antennas 5 and 6 is larger than 1 / 2λ, and the reflector 4 and the dipole antenna Is made smaller than 1 / 4λ, and the parasitic element is made to resonate at a high operating frequency, and the distance is made narrower than the distance between the dipole antennas 5 and 6, so that the pair of dipole antennas 5 and 6 In addition, an antenna device that can be shared in two used frequency bands without changing the antenna aperture width can be provided.
[Modification]
FIG. 14 shows an example of an antenna device in which two antenna zones of 6 sectors are formed by shifting the antenna directivity direction of the 60 ° beam antenna of the present invention by 60 °. A front view is shown in FIG. 14a and a plan view thereof is shown in FIG. 14b. FIG. 14 shows the antenna devices 101 and 201 of the embodiment shown in FIG. 1 with the former folding lines of the main reflector 1 and the side reflector 3 and the latter folding lines of the main reflector 1 and the side reflector 2. Are arranged so that the angle formed by the two main reflectors 1 is 120 °, that is, the antenna devices 101 and 201 are arranged by shifting the antenna directing direction by 60 °. The same components as those in FIG.

  FIG. 15 shows an antenna device which is arrayed in the length direction of a dipole antenna for the purpose of increasing the gain of the 60 ° beam antenna of the present invention. FIG. 15 shows an example in which a plurality of N antenna devices 101 of the embodiment shown in FIG. 1 are arranged in the extending direction of the first dipole antenna and the second dipole antennas 5 and 6. Normally, vertical polarization is used in a mobile communication system in which this type of 60 ° beam antenna is used for a base station. Thus, arranging a plurality of arrays in the length direction of a dipole antenna in this way It is effective to increase the gain. The same components as those in FIG. 1 used in the description of the present invention have the same reference numerals, and a description thereof will be omitted.

  For the purpose of increasing the antenna gain of the antenna device in which two directivity zones of six sectors are formed by shifting the directivity direction of the antenna of the 60 ° beam antenna of this embodiment shown in FIG. An example in which a plurality of dipole antennas are arrayed in the length direction is shown. This is an example in which a plurality of N antenna devices 101 and 201 shown in FIG. 14 are arranged in the extending direction of the first dipole antenna and the second dipole antennas 5 and 6. In this example, two antenna devices according to the present invention are combined with the antenna directing direction shifted by 60 °. However, if two or more antenna devices are combined, it is possible to widen the coverage of the 6-sector wireless zone.

It is the schematic which shows the basic composition of the antenna apparatus of this invention. It is a figure which shows the relationship between the antenna opening width of this invention, and the directivity in a horizontal surface. It is a figure which shows the relationship between the antenna opening width of this invention, and the directivity in a horizontal surface. It is a diagram showing the relationship between the vertical distance d _V and horizontal plane directivity of the dipole antenna of the antenna device of the present invention and the reflector. It is a figure which shows the relationship between the length L of the parasitic element of the antenna apparatus of this invention, and a return loss. It is a figure which shows the relationship between the length L of the parasitic element of the antenna apparatus of this invention, and directivity in a horizontal surface. Is a diagram illustrating the difference in horizontal plane directivity between the horizontal distance S ₁ and using the frequency band of the dipole antenna and the parasitic element of the antenna device of the present invention. Is a diagram showing the relationship between the horizontal distance S ₁ and the reflection attenuation amount of the dipole antenna and the parasitic element of the antenna device of the present invention. Is a diagram showing the relationship between the vertical spacing S ₂ and the reflection attenuation amount of the dipole antenna and the parasitic element of the antenna device of the present invention. Is a diagram showing the relationship between the vertical spacing S ₂ and horizontal plane directivity of the dipole antenna and the parasitic element of the antenna device of the present invention. It is a figure which shows the frequency characteristic of the return loss of the antenna apparatus of this invention. It is a figure which shows the directivity pattern of the use frequency band 1.7GHz of the antenna apparatus of this invention. It is a figure which shows the directivity pattern of the use frequency band 2.0GHz of the antenna apparatus of this invention. It is a figure which shows the example which formed two of the radio zones of 6 sector structure by the antenna device of this invention. It is the schematic which shows the example which made the antenna device of this invention shown in FIG. 1 into an array. It is the schematic which shows the example which made the antenna apparatus of this invention shown in FIG. 14 into an array. It is a figure which shows an example of the conventional multifrequency shared antenna. It is the schematic which shows the structure of the conventional 60 degree beam antenna.

Claims (7)

A reflector,
First and second dipole antennas arranged in front of the reflector and arranged in parallel with the reflector;
First and second parasitic elements are provided in front of the first and second dipole antennas,
The reflector includes a rectangular flat main reflector and first and second side reflectors bent forward from both side edges of the main reflector,
It said first and second dipole antenna, the main reflector and parallel respectively bending line of the first and second side reflectors, opposed to keeping the main reflector and distance d _V, a first dipole antenna first opposed at a distance d _H between 2 dipole antenna,
It said first and second parasitic elements, for each first and second dipole antenna is the first and second side reflectors and the distance S ₁ just opposite, and only the main reflector and the distance S ₂ On the other side,
The first and second dipole antennas include one feeding point for a high-frequency signal having a first use frequency and a second high-frequency signal having a frequency lower than the first use frequency,
The effective length of the first and second dipole antennas is ½ of the wavelength λ of the second high-frequency signal, and the distance d _V is smaller than a distance of ¼ of the wavelength, The antenna device according to claim 1, wherein the distance d _H is larger than a distance of ½ of the wavelength λ. The distance _{d V} antenna device according to claim 1, characterized in that in the range of 0.20λ ≧ _{d V} ≧ 0.175λ. The distance d _H is the antenna device according to any one of the claims 1 and 2, characterized in that in the range of 0.53λ ≦ d _H ≦ 0.56λ. The distance S ₁ is in the range of 0λ ≦ S ₁ ≦ 0.066λ, the distance S ₂ is in the range of 0.04λ ≦ S ₂ ≦ 0.056λ, and the length L of the first and second parasitic elements 4. The antenna device according to claim 1, wherein _P is in a range of 0.30λ ≦ L _P ≦ 0.345λ.   The angle θ formed between the plane parallel to the dipole antenna and the first and second side reflectors is 0 °, and the length W in the extending direction of the first and second side radiators is 0.056λ ≦ W. 5. The antenna device according to claim 1, wherein the antenna device is within a range of 0.141λ.   An antenna device according to any one of claims 1 and 5, wherein two or more sets of adjacent antenna devices are integrated by shifting an angle formed by the antenna directing direction of the antenna device by 60 °. .   7. An antenna device, wherein a plurality of antenna devices according to claim 1 and 6 are arrayed in the length direction of a dipole antenna.

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