JP7115022B2 - antenna device - Google Patents

Description

The present invention relates to an antenna device.

A high-speed wireless access system using electromagnetic waves in the 5 GHz band includes IEEE802. Some are based on the standard of a. IEEE802. The high-speed wireless access system based on the standard of a uses an orthogonal frequency division multiplexing (OFDM) modulation method to stabilize characteristics in a multipath fading environment and achieve a maximum throughput of 54 Mbit/s. Realized.

In addition, in a high-speed wireless access system based on the IEEE 802.11n standard, MIMO (Multiple Input Multiple Output) that performs space division multiplexing on the same wireless channel using multiple antennas and two 20 MHz frequency channels are used simultaneously. A maximum transmission rate of 600 Mbits/s is achieved by using channel bonding technology that utilizes 40 MHz frequency channels.

Also, in a high-speed wireless access system based on the IEEE802.11ac standard, channel bonding technology that simultaneously uses four 20 MHz frequency channels as an 80 MHz frequency channel and multi-user MIMO are used in the same wireless channel. , using the transmission technology of Spatial Division Multiple Access (SDMA), which performs simultaneous transmission to a plurality of wireless stations, realizes wireless communication that is faster and more efficient than the IEEE 802.11n standard.

Furthermore, in order to improve the transmission characteristics of a high-speed wireless access system, switching the directivity of antennas used in the system is under study. For example, a technology has been proposed in which an antenna device having a dipole antenna and a plurality of parasitic elements is arranged in a base station and the directivity of the antenna device is switched by controlling the parasitic elements (see Non-Patent Document 1). By switching the directivity of the antenna device according to the communication environment of a mobile communication terminal such as a smart phone or a tablet-type terminal that wirelessly communicates with a base station, the received power of the mobile communication terminal can be increased.

J. Cheng, M. Hashiguchi, K. Iigusa, T. Ohira,“Electronically steerable parasitic array radiator antenna for omni- and sector pattern forming applications to wireless ad hoc networks,”IEEE Proceedings Microwaves, antennas and propagation, vol.150, no.4, Aug. 2003.

In recent years, base stations have been installed with high density in order to provide high communication quality. In such a communication environment, depending on the mobile communication terminal that wirelessly communicates with the base station, there are cases where omni-directionality, which is omni characteristics, and directional characteristics (horizontal and vertical planes), which is representative of sector characteristics, are suitable. There is However, in the prior art, since the directivity of the horizontal plane is switched between the omni characteristic and the sector characteristic by electronic control according to the communication environment, there is a problem that the cost and power of the parasitic element for electronic control are required.

SUMMARY OF THE INVENTION An object of the present invention is to provide an antenna device capable of controlling directivity in a horizontal plane at a lower cost than conventional antenna devices.

A first aspect of the present invention is an antenna section in which an antenna element and a plurality of parasitic elements are arranged on a plane on a circle having a predetermined radius centered on a position where the antenna element is arranged, and an upper part of the antenna section. and a lower portion, and includes a first adjustment section for adjusting the length of each of the plurality of parasitic elements, and a setting section for setting the first adjustment section according to the directivity of the antenna section. characterized by

A second invention is the first invention, further comprising a plurality of first adjustment units, wherein the setting unit selects one of the plurality of first adjustment units according to the directivity of the antenna unit. It is characterized by selecting and setting the selected first adjustment section.

A third invention is characterized in that, in the first invention, the setting section rotates the first adjustment section around a position where the antenna element is arranged to set the direction according to the directivity of the antenna section. .

In a fourth aspect based on the third aspect, a plurality of second adjusters are arranged in the antenna section so as to face the first adjuster and adjust the length of each of the plurality of parasitic elements together with the first adjuster. and a plurality of first adjustment units, wherein the setting unit selects the first adjustment unit and the second adjustment unit according to the directivity of the antenna unit among the plurality of first adjustment units and the plurality of second adjustment units is selected, and the selected first adjustment unit and second adjustment unit are rotated and set.

According to a fifth invention, in any one of the first to fourth inventions, a receiving unit for receiving electromagnetic wave signals from each of a plurality of communication terminals via an antenna element, and a measuring unit that measures the received power of each signal; a control unit that determines a first directivity to be set in the antenna unit among the plurality of first directivities based on the received power, and controls the setting unit to achieve the determined first directivity. characterized by

According to a sixth aspect, in any one of the first to fourth aspects, a receiving unit for receiving electromagnetic wave signals from each of a plurality of communication terminals via an antenna element; a measuring unit that measures the received power of each signal; and a cell identifier indicating a cell in which the communication terminal is located, which is included in the signal of each of the plurality of communication terminals. and a control unit that controls the setting unit so as to achieve the determined first directivity.

ADVANTAGE OF THE INVENTION This invention can control the directivity of a horizontal plane at low cost compared with the former.

1 illustrates an embodiment of an antenna device; FIG. FIG. 2 is a diagram showing an example of a plurality of adjustment units included in the antenna device shown in FIG. 1; 2 is a diagram showing an example of directivity of the antenna device shown in FIG. 1; FIG. 2 is a diagram showing another example of the directivity of the antenna device shown in FIG. 1; FIG. Fig. 3 shows another embodiment of an antenna device; FIG. 6 is a diagram showing an example of an adjustment unit included in the antenna device shown in FIG. 5; 6 is a diagram showing an example of directivity of the antenna device shown in FIG. 5; FIG. Fig. 3 shows another embodiment of an antenna device; 9 is a diagram showing an example of a control device shown in FIG. 8; FIG. FIG. 10 is a diagram showing an example of a measurement table shown in FIG. 9; FIG. FIG. 9 is a diagram showing an example of directivity setting processing in the antenna device shown in FIG. 8;

Embodiments will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an antenna device.

The antenna device 100 shown in FIG. 1 is arranged, for example, in a base station, receives electromagnetic waves transmitted from mobile communication terminals such as smartphones and tablet terminals, and transmits electromagnetic waves of signals including data to the mobile communication terminals. do. Antenna device 100 has antenna element 10 , four parasitic elements 20 ( 20 ( 1 ) to 20 ( 4 )), adjustment section 30 , setting section 40 and coupling section 50 .

The antenna element 10 is, for example, a sleeve antenna, and has an element length of half the wavelength in the Z-axis direction. The antenna element 10 is arranged so as to extend in the Z-axis direction perpendicular to the horizontal XY plane. The antenna element 10 transmits a signal including data from the base station to the mobile communication terminal via the coupling unit 50 by electromagnetic waves. Further, the antenna element 10 receives electromagnetic waves transmitted from the mobile communication terminal, and outputs signals of the received electromagnetic waves to the base station via the coupling unit 50 . Note that the antenna element 10 may be a dipole antenna or the like.

The parasitic element 20 is a cylindrical metal member such as copper, and is arranged on a circle with a radius R centered on the position where the antenna element 10 is arranged so as to be lifted from the XY plane at equal intervals using the frame FR1. be done. That is, the positions of the parasitic elements 20(1)-20(4) are (R, 0), (0, R), (-R, 0) and (0,-R). The radius R is set to a distance equal to or greater than one-eighth the free-space wavelength that can reduce the influence of mutual coupling with the antenna element 10 . Also, a plurality of parasitic elements 20 other than four may be arranged. The antenna element 10 and the parasitic element 20 operate as an antenna section.

Among the four parasitic elements 20 shown in FIG. 1, the adjustment unit 30 includes a metal member 31 for adjusting the element length of the parasitic element 20 that operates as a reflector of the antenna element 10, and the metal member 31. and a frame FR2, which is arranged below the parasitic element 20. As shown in FIG. In FIG. 1, for example, in order to operate the parasitic elements 20(2)-20(4) as reflectors, metal members 31 are framed at the positions of each of the parasitic elements 20(2)-20(4). Placed in FR2. The parasitic element 20 ( 1 ) operates as a director for the antenna element 10 . Note that the adjustment unit 30 may be arranged above the antenna element 10 .

Also, the element length of the parasitic element 20 when operating as a director is adjusted to 0.4 wavelength in the free space wavelength. For example, when the frequency of electromagnetic waves is 5 GHz, 0.4 wavelength is approximately 24 mm. In addition, when operating as a reflector, the length of the metal member 31 is set to 0.18 wavelength so that the total element length of the parasitic element 20 and the metal member 31 is 0.58 wavelength in the free space wavelength. adjusted. When the frequency of the electromagnetic wave is 5 GHz, 0.58 wavelength is approximately 32 mm and 0.18 wavelength is approximately 8 mm. The lengths of the parasitic element 20 and the metal member 31 are preferably determined as appropriate according to the communication environment in which the base station is installed, the location at which the base station is installed, and the like.

Further, the antenna device 100 has a plurality of adjustment units 30 in which metal members 31 are arranged on the frame FR2 at the positions of the parasitic elements 20 that operate as reflectors according to the directivity of the antenna device 100 . The plurality of adjustment units 30 will be described with reference to FIG. 2 .

The setting unit 40 is a drive device including a motor and the like, and sets the adjustment unit 30 according to the directivity of the antenna device 100 based on control instructions from a computer device or the like included in the base station. For example, when a plurality of adjustment units 30 are arranged on a turntable or the like, the setting unit 40 selects one adjustment unit 30 according to the directivity of the antenna device 100 based on a control instruction from the computer device of the base station. Then, the selected adjustment section 30 is set below the parasitic element 20 .

The coupling unit 50 is an antenna connector or the like, and connects the antenna device 100 and the base station with a coaxial cable or the like. The coupling unit 50 outputs the electromagnetic wave signal received by the antenna device 100 to the base station, and outputs the signal including the data from the base station to the antenna device 100 .

FIG. 2 shows an example of the plurality of adjustment units 30 included in the antenna device 100 shown in FIG. In FIG. 2, four adjusters 30(1)-30(4) are shown. The adjustment unit 30(1) shown in FIG. 2(a) has a metal member 31 disposed on the frame FR2 at each position of the parasitic elements 20(2) to 20(4) in the same manner as in FIG. The parasitic elements 20(2)-20(4) are operated as reflectors. The adjustment unit 30(2) shown in FIG. 2(b) has a metal member 31 disposed on the frame FR2 at each position of the parasitic elements 20(1), 20(3), and 20(4). Feeding elements 20(1), 20(3) and 20(4) are operated as reflectors. The adjustment unit 30(3) shown in FIG. 2(c) has a metal member 31 disposed on the frame FR2 at each position of the parasitic elements 20(1), 20(2), and 20(4). The feeding elements 20(1), 20(2) and 20(4) are operated as reflectors. The adjustment unit 30(4) shown in FIG. 2(d) arranges the metal member 31 on the frame FR2 at each position of the parasitic elements 20(1) to 20(3), )-20(3) act as reflectors.

Although FIG. 2 shows the four adjustment units 30(1) to 30(4), the antenna device 100 can operate with one parasitic element 20 as a reflector, or with two parasitic elements 20 It is preferable to have a plurality of adjustment sections 30 such as when operating the as a reflector. The plurality of adjustment units 30 are arranged, for example, on a turntable or the like, and the setting unit 40 selects one adjustment unit 30 according to the directivity of the antenna device 100, and selects the selected adjustment unit 30 as a parasitic element. Set to the bottom of 20. Thereby, the antenna device 100 can control the directivity in the horizontal plane.

FIG. 3 shows an example of directivity of the antenna device 100 shown in FIG. FIG. 3 shows the case where the directivity of the horizontal plane of the antenna device 100 becomes omni characteristics by not arranging the adjustment unit 30 below the parasitic elements 20, that is, by all the parasitic elements 20 operating as directors. shows the results of a simulation of In addition, in the simulation of FIG. 3, the frequency of electromagnetic waves shall be 5 GHz.

FIG. 3(a) shows the directivity in the vertical plane (XZ plane) with a dashed line. FIG. 3(b) shows the directivity in the horizontal plane (XY plane) with a dashed line. As shown in FIG. 3A, the directivity of the antenna device 100 in the vertical plane exhibits a beam pattern similar to that of a sleeve antenna, that is, a half-wave dipole antenna. On the other hand, as shown in FIG. 3B, the directivity of the vertical plane of the antenna device 100 is omnidirectional, ie, omni characteristics.

FIG. 4 shows another example of the directivity of the antenna device 100 shown in FIG. In FIG. 4, the adjustment unit 30(1) shown in FIG. 2(a) is set, the parasitic element 20(1) operates as a director, and the parasitic elements 20(2)-20(4) The result of the simulation when the directivity of the horizontal plane of the antenna apparatus 100 becomes the sector characteristic directed to the positive X-axis direction by operating as a reflector is shown. In the simulation of FIG. 4, the frequency of electromagnetic waves is assumed to be 5 GHz.

FIG. 4(a) shows the directivity in the vertical plane with a broken line, and FIG. 4(b) shows the directivity in the horizontal plane with a broken line. As shown in FIG. 4(a), the antenna device 100 has, as the directivity in the vertical plane, a beam pattern that exhibits the maximum gain in the positive X-axis direction. On the other hand, as shown in FIG. 4(b), the antenna device 100 has, as the directivity in the horizontal plane, sector characteristics of a beam pattern that exhibits the maximum gain in the positive X-axis direction.

As described above, in the embodiment shown in FIGS. 1 to 4, the antenna device 100 adjusts the element length of the parasitic element 20 according to the directivity of the antenna device 100 using the plurality of adjusters 30, thereby directivity can be controlled to omni or sector characteristics. The antenna device 100 does not require electronically controlled power supply except when the setting unit 40 operates to adjust the element length of the parasitic element 20 . Therefore, the antenna device 100 can control the directivity in the horizontal plane at a lower cost than the conventional one.

Although the antenna device 100 has a plurality of adjustment units 30 as shown in FIG. 2, it may have any one adjustment unit 30 . For example, when the antenna device 100 has the adjustment unit 30(1) shown in FIG. , the position of the antenna element 10 is set by rotating the adjusting section 30(1). As a result, the antenna apparatus 100 can operate one adjusting section 30(1) as the adjusting sections 30(2) to 30(4), and can be miniaturized.

Further, when the setting unit 40 rotates the adjustment unit 30, the adjustment unit 30 includes three metal members 31 for operating the three parasitic elements 20 as reflectors, and one parasitic element 20 as a reflector. One metal member 31 when operating as a parasitic element 20 and two metal members 31 when operating two parasitic elements 20 as reflectors may be arranged on the frame FR2. Then, the setting unit 40 rotates and sets the adjustment unit 30 to the center of the antenna element 10 at a rotation angle corresponding to the directivity of the antenna device 100 based on a control instruction from the computer device of the base station. Thereby, the antenna device 100 can operate one to three parasitic elements 20 among the four parasitic elements 20 as reflectors. When two parasitic elements 20 are operated as reflectors, the adjusting unit 30 includes two metal members 31 when using two adjacent parasitic elements 20 as reflectors, and the antenna element 10. Two metal members 31 are arranged on the frame FR2 when the two opposing parasitic elements 20 are used as reflectors.

FIG. 5 shows another embodiment of the antenna device. Elements having the same or similar functions as those described with reference to FIG. 1 are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

The antenna device 100A shown in FIG. 5 is arranged, for example, in a base station, receives electromagnetic waves transmitted from mobile communication terminals such as smartphones and tablet terminals, and transmits electromagnetic waves of signals including data to the mobile communication terminals. do. The antenna device 100A has an antenna element 10, four parasitic elements 20a (20a(1)-20a(4)), adjustment sections 30a and 30b, a setting section 40a and a coupling section 50. FIG.

The parasitic element 20a is a cylindrical metal member such as copper, and similarly to the parasitic element 20 shown in FIG. They are arranged on the circumference at equal intervals so as to float from the XY plane. That is, the positions of the parasitic elements 20a(1) to 20a(4) are (R, 0), (0, R), (-R, 0) and (0,-R). The radius R is set to a distance equal to or greater than one-eighth the free-space wavelength that can reduce the influence of mutual coupling with the antenna element 10 . Also, a plurality of parasitic elements 20a other than four may be arranged. The antenna element 10 and the parasitic element 20a operate as an antenna section.

Of the four parasitic elements 20a shown in FIG. 5, the adjustment unit 30a includes a metal member 31 for adjusting the element length of the parasitic element 20a that operates as a reflector of the antenna element 10, and a parasitic element that operates as a director. It has a metal member 32 for adjusting the element length of the feeding element 20a and a frame FR2 on which the metal members 31 and 32 are arranged. The adjusting section 30a is arranged below the parasitic element 20a.

In addition, the adjustment unit 30b includes a metal member 60 for adjusting the element length of the parasitic element 20a operated as a reflector of the antenna element 10 among the four parasitic elements 20a shown in FIG. It has a metal member 61 for adjusting the element length of the parasitic element 20a to be driven, and a frame FR3 on which the metal members 60, 61 are arranged. The adjusting section 30b is arranged above the parasitic element 20a. In FIG. 5, for example, in order to operate the parasitic elements 20a(2) to 20a(4) as reflectors, metal members 31 are provided at respective positions of the parasitic elements 20a(2) to 20a(4). 30a, and the metal member 60 is placed on the frame FR3 of the adjusting portion 30b. In addition, in order to operate the parasitic element 20a(1) as a wave director, the metal member 32 is arranged on the frame FR2 of the adjusting section 30a at the position of the parasitic element 20a(1), and the metal member 61 is arranged on the adjusting section 30b. is placed in the frame FR3 of

Here, when operating as a wave director, the total element length of the parasitic element 20a, the metal member 32, and the metal member 61 is 0.4 wavelength in the free space wavelength (for example, when the frequency of the electromagnetic wave is 5 GHz, it is about 24 mm), the lengths of the parasitic element 20a and the metal members 32 and 61 are adjusted. Further, when operating as a reflector, the total element length of the parasitic element 20a, the metal member 31, and the metal member 60 is 0.58 wavelength in the free space wavelength (about 32 mm when the frequency of the electromagnetic wave is 5 GHz). , the lengths of the parasitic element 20a and the metal members 31 and 60 are adjusted. The lengths of the parasitic elements 20a are appropriately determined to have the same length according to the communication environment in which the base station is installed, the location at which the base station is installed, and the like. In addition, the length of each of the metal members 31-32 and 60-61 is appropriately determined according to the directivity of the antenna device 100A, the communication environment in which the base station is installed, the location where the base station is installed, and the like. is preferred. The lengths of the metal members 31-32 and 60-61 of the adjusting portions 30a and 30b will be explained with reference to FIG.

The setting unit 40a is a driving device including a motor and the like, and adjusts the position of the antenna element 10 as a center according to the directivity of the antenna device 100A based on the control instruction of the computer device or the like included in the base station. , 30b are set. The operation of the setting unit 40a will be described with reference to FIG.

FIG. 6 shows an example of the adjustment units 30a and 30b included in the antenna device 100A shown in FIG. FIG. 6 shows adjusting sections 30a and 30b when the directivity of the antenna device 100A shown in FIG. 5 is the sector characteristic. The adjustment units 30a and 30b shown in FIG. 6 have (2N+1) combinations (N is a positive integer) in order to control the directivity in the vertical plane as well as the directivity in the horizontal plane.

For example, the adjusters 30a(N) and 30b(N) show the case where the antenna device 100A has the directivity of the sector characteristics shown in FIG. On the other hand, the adjustment units 30a(m) and 30b(m) control the directivity of the vertical plane of the antenna device 100A so that it is directed in the negative Z-axis direction compared to the directivity shown in FIG. m is an integer from -N to (N-1)). That is, the adjusters 30a(m) and 30b(m) move the director and the reflector including the parasitic element 20a to the positive Z direction by moving amounts corresponding to the lengths of the metal members 31-32 and 60-61. By moving in the axial direction, the directivity of the vertical plane of the antenna device 100A is moved in the negative Z-axis direction. Then, the adjustment units 30a(-N) and 30b(-N) move the director and reflector including the parasitic element 20a in the positive Z-axis direction by the maximum amount of movement with respect to the antenna element 10. , the directivity of the vertical plane of the antenna device 100A is oriented in the negative Z-axis direction at the maximum angle.

The lengths of the metal members 31-32 and 60-61 of the adjusting portions 30a(m) and 30b(m) are, for example, 0.02 to 0.42 wavelengths (when the frequency of the electromagnetic wave is 5 GHz, about 1 mm to about 25 mm.

Each of the (2N+1) pairs of adjustment units 30a and 30b is arranged, for example, on a turntable or the like, and the setting unit 40a sets one pair according to the directivity of the antenna device 100A based on a control instruction from the computer device of the base station. select the adjustment units 30a and 30b. The setting unit 40a installs the selected pair of adjusting units 30a and 30b respectively below and above the parasitic element 20a. Then, the setting unit 40a rotates and sets the installed adjustment units 30a and 30b around the position of the antenna element 10 at a rotation angle corresponding to the directivity of the antenna device 100A.

FIG. 6 shows the adjustment units 30a and 30b when the directivity of the antenna device 100A is the sector characteristic, but when the directivity of the antenna device 100A is the omni characteristic, one parasitic element 20a is used as a reflector. It is preferable to have adjustment units 30a and 30b for operating and for operating the two parasitic elements 20a as reflectors.

FIG. 7 shows an example of directivity of the antenna device 100A shown in FIG. 7, for example, the adjustment units 30a and 30b that provide a movement amount of 10 mm in the positive Z-axis direction are set in the antenna device 100A, the parasitic element 20a(1) operates as a director, and the parasitic element 20a (2)-20a(4) operates as a reflector to show the result of a simulation in which the directivity of the horizontal plane of the antenna device 100 becomes a positive sector characteristic in the X-axis direction. In addition, in the simulation of FIG. 7, the frequency of the electromagnetic wave is assumed to be 5 GHz.

FIG. 7(a) shows the directivity in the vertical plane with a broken line, and FIG. 7(b) shows the directivity in the horizontal plane with a broken line. As shown in FIG. 7(a), the parasitic element 20a of the antenna device 100A moves 10 mm in the positive Z-axis direction, so that compared to the case of FIG. (approximately 10 degrees) in the direction of the negative Z-axis as the directivity of the vertical plane. That is, the antenna device 100A can control the directivity in the vertical plane by arranging the adjustment units 30a and 30b. On the other hand, as shown in FIG. 7(b), the antenna device 100A has sector characteristics similar to those in FIG. 4(b) in the horizontal plane.

Moreover, the antenna device 100A can control the directivity in the vertical plane as well as the directivity in the horizontal plane by using the adjustment units 30a and 30b when the directivity is the omni characteristic, as in the case of FIG.

As described above, in the embodiments shown in FIGS. 5 to 7, the antenna device 100A adjusts the element length of the parasitic element 20a according to the directivity of the antenna device 100A using the plurality of adjusters 30a and 30b. , the directivity in the horizontal plane can be controlled to omni or sector characteristics. The antenna device 100A does not require electronically controlled power supply except when the setting unit 40a operates to adjust the element length of the parasitic element 20a. Therefore, the antenna device 100A can control the directivity in the horizontal plane at a lower cost than in the related art. Further, the antenna device 100A uses the adjustment units 30a and 30b to move the director and the reflector in the Z-axis direction, thereby controlling the directivity in the horizontal plane to the omni characteristic or the sector characteristic, and the directivity in the vertical plane. Directivity can be controlled.

FIG. 8 shows another embodiment of the antenna device. Elements having the same or similar functions as the elements described in FIG. 5 are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

The antenna device 100B shown in FIG. 8 is arranged in a base station, for example, similarly to the antenna device 100A shown in FIG. It transmits electromagnetic waves of signals containing data to the mobile communication terminal. Antenna device 100B has antenna element 10, four parasitic elements 20a (20a(1)-20a(4)), adjustment sections 30a and 30b, setting section 40a, coupling section 50, and control device 200. FIG.

The control device 200 is a computer device having an arithmetic processing unit such as a processor and a storage unit such as a memory. For example, based on a control instruction from the base station, the control device 200 controls each element of the antenna device 100B by causing the arithmetic processing section to execute a program stored in the storage section.

FIG. 9 shows an example of the control device 200 shown in FIG. As shown in FIG. 9 , the control device 200 has a receiving section 210 , a measuring section 220 , a control section 230 and a storage section 240 .

The receiving unit 210 receives, for example, the electromagnetic wave signal received by the antenna element 10 from the mobile communication terminal via the coupling unit 50 .

Measuring section 220 measures the received power of the signal received by receiving section 210 . The measurement unit 220 also acquires position information indicating the position of the mobile communication terminal added to the received signal. Then, for example, the measurement unit 220 stores the reception power and location information of the mobile communication terminal, and the identification information indicating the mobile communication terminal together with the directivity information indicating the directivity set in the antenna device 100B, and the storage unit 240. , and stored in the measurement table MT.

Control unit 230 is a processor or the like, and operates by executing a program stored in storage unit 240 . For example, when setting the directivity of the antenna device 100B, the control unit 230 sequentially sets a plurality of predetermined directivities to the antenna device 100B. Control section 230 causes measurement section 220 to measure the received power of the signal from the mobile communication terminal in each directivity, and stores the measured received power in measurement table MT. Then, control section 230 refers to measurement table MT to determine the directivity of antenna device 100B. The control unit 230 outputs a control instruction to set the determined directivity to the setting unit 40a. Operation of the control unit 230 will be described with reference to FIG.

The storage unit 240 is a memory or the like, and stores a program executed by a processor or the like, a measurement table MT, or the like. The measurement table MT will be described with reference to FIG.

FIG. 10 shows an example of the measurement table MT shown in FIG. The measurement table MT includes a directivity area RA for storing horizontal directivity, a movement amount area RB for storing the amount of movement, and a terminal area R1- for storing the received power and position of each of the N mobile communication terminals. RN.

The directivity area RA stores "omni characteristics" indicating the directivity of the horizontal plane set in the antenna device 100B by the control unit 230, and "sector 1", "sector M", etc., which are M sector characteristics. . For example, when the control unit 230 refers to the measurement table MT and selects “omni characteristics” from the directivity area RA, the control unit 230 outputs a control instruction to set the directivity of the antenna device 100B to the omni characteristics to the setting unit 40a. do. Further, when "sector 1" is selected from the directivity area RA, the control section 230 outputs a control instruction to set the directivity of the antenna device 100B to the sector characteristics of the "sector 1" to the setting section 40a.

In the movement amount area RB, the amount of movement in the Z-axis direction of the adjustment units 30a and 30b set in the antenna device 100B by the control unit 230 is stored for each directivity stored in the directivity area RA. In the movement amount area RB shown in FIG. 10, for example, the movement amount is stored at a predetermined interval such as 5 mm, with values ranging from 0 mm to 30 mm. Then, the control unit 230 refers to the measurement table MT, selects the directivity of the horizontal plane from the directivity area RA, selects the movement amount from the movement amount area RB, and selects the adjustment unit 30a having the selected movement amount. 30b is output to the setting unit 40a.

Terminal areas RC1-RCN store the received power and position of signals from each of the N mobile communication terminals measured by measuring section 220 in each directivity of directivity area RA set in antenna device 100B. be done. Note that each of the N mobile communication terminals may remain at the same position while the directivity of the antenna device 100B is sequentially changed, and one mobile communication terminal may have one antenna device 100B with one directivity. While set to one, it may move to each of the N positions. Moreover, the mobile communication terminal may be a mobile communication terminal of a general user, or may be a communication terminal of a carrier that is used for measurement and registered in advance.

FIG. 11 shows an example of directivity setting processing in the antenna device 100B shown in FIG. The processing shown in FIG. 11 may be executed when the antenna device 100B is provided in the base station, or may be executed at predetermined intervals such as one year.

In step S100, the control unit 230, for example, refers to the measurement table MT shown in FIG. Set to 100B. A plurality of directivities obtained by combining the directivity area RA and the movement amount area RB is an example of a plurality of first directivities.

At step S110, the measurement unit 220 measures the reception power of the signals received from each of the N mobile communication terminals via the antenna device 100B having the directivity set at step S100. Then, measuring section 220 outputs the received power and location information of the mobile communication terminal and the identification information indicating the mobile communication terminal to storage section 240 together with the directivity information indicating the directivity set in antenna device 100B. and store it in the measurement table MT.

In step S120, control unit 230 determines whether or not there is a next directivity to be set in antenna device 100B among a plurality of directivities obtained by combining directivity area RA and movement amount area RB. If there is the next directivity, the processing of the antenna device 100B proceeds to step S100. On the other hand, when there is no next directivity, that is, when all of the multiple directivities are set in the antenna device 100B, the processing of the antenna device 100B proceeds to step S130.

At step S130, the control unit 230 refers to the measurement table MT stored in the storage unit 240 and determines the directivity of the antenna device 100B. For example, the control unit 230 acquires the received power of a communication terminal of a communication carrier registered in advance in the measurement table MT. Then, the control unit 230 extracts from the directivity area RA and the movement amount area RB, the directivity and the amount of movement in the horizontal plane when the received power reaches the maximum value in the communication terminal of the communication carrier. Control unit 230 determines the extracted directivity and movement amount as the directivity to be set for antenna device 100B.

Note that the control unit 230 may extract the directivity and the amount of movement in the horizontal plane when the received power shows the minimum value in the communication terminal of the communication carrier from the directivity area RA and the amount of movement area RB. As a result, the control unit 230 can reduce the influence of interference and the like on other adjacent base stations, and improve communication quality.

In step S140, control unit 230 outputs a control instruction for setting the determined directivity to setting unit 40a. Then, the setting unit 40a selects the adjustment units 30a and 30b that have been instructed to be controlled, and installs the selected adjustment units 30a and 30b in the lower and upper portions of the antenna device 100B. The setting unit 40a rotates and sets the adjustment units 30a and 30b around the position of the antenna element 10 at a rotation angle corresponding to the directivity that is instructed to be controlled.

Then, the antenna device 100B ends the setting process.

Note that the control device 200 may also perform the setting process shown in FIG. 11 for the antenna device 100 shown in FIG. 1, as in the case of the antenna device 100B.

Also, although the control device 200 determines the directivity of the antenna device 100B based on the received power of the signals from the plurality of mobile communication terminals received via the antenna device 100B, the present invention is not limited to this. For example, if the base station supports IEEE802. When wirelessly communicating with a mobile communication terminal based on a standard such as ax, a cell identifier indicating which base station cell the mobile communication terminal is located in is added to a signal from the mobile communication terminal. In this case, the control device 200 may generate a table storing the received power in each directivity for each cell identifier instead of the mobile communication terminal. Then, the control device 200 uses the generated table, for example, to determine the directivity of the antenna device 100B that maximizes or minimizes the received power for the cell identifier added to the signal of the communication terminal of the pre-registered communication carrier. may decide. As a result, the control device 200 can reduce the influence of interference and the like on other adjacent base stations, and improve communication quality.

As described above, in the embodiments shown in FIGS. 8 to 11, the antenna device 100B adjusts the element length of the parasitic element 20a according to the directivity of the antenna device 100B using the plurality of adjusters 30a and 30b. , the directivity in the horizontal plane can be controlled to omni or sector characteristics. The antenna device 100B does not require electronically controlled power supply except when the setting unit 40a operates to adjust the element length of the parasitic element 20a. Therefore, the antenna device 100B can control the directivity in the horizontal plane at a lower cost than the conventional one. Further, the antenna device 100B uses the adjustment units 30a and 30b to move the director and the reflector in the Z-axis direction, thereby controlling the directivity in the horizontal plane to the omni characteristic or the sector characteristic, and the directivity in the vertical plane. Directivity can be controlled.

From the detailed description above, the features and advantages of the embodiments will become apparent. It is intended that the claims cover the features and advantages of such embodiments without departing from their spirit and scope. In addition, any improvements and modifications will readily occur to those skilled in the art. Accordingly, the scope of inventive embodiments is not intended to be limited to what has been described above, and suitable modifications and equivalents within the disclosed scope of the embodiments may be relied upon.

10... Antenna elements; 20(1)-20(4), 20a(1)-20a(4)... Parasitic elements; 30(1)-30(4), 30a(-N)-30a(N), 30b(-N)-30b(N) Adjusting unit; 31, 32, 60, 61 Metal member; 40, 40a Setting unit; 50 Coupling unit; 100, 100A, 100B Antenna device; 210 -- Receiving section; 220 -- Measuring section; 230 -- Control section; 240 -- Storage section; FR1, FR2, FR3 -- Frame;

Claims (6)

antenna elements arranged on a predetermined plane so as to extend in a direction perpendicular to the plane ; an antenna unit comprising a plurality of parasitic elements arranged to extend in the vertical direction ;
a first adjustment unit arranged on either one of the upper part and the lower part of the antenna unit and adjusting the length of each of the plurality of parasitic elements;
A setting unit that sets the first adjustment unit according to the directivity of the antenna unit ,
The first adjustment unit includes one or more metal members arranged at ends of one or more of the plurality of parasitic elements,
The setting unit sets the first adjustment unit so that the metal member is arranged at an end of one of the plurality of parasitic elements that is operated as a reflector, according to the directivity. Antenna device characterized by: In the antenna device according to claim 1,
comprising a plurality of the first adjustment units ,
The setting unit selects one of the plurality of first adjustment units according to the directivity , and sets the selected first adjustment unit. . In the antenna device according to claim 1 or 2 ,
The antenna device, wherein the setting section rotates the first adjustment section around a position where the antenna element is arranged to set the directivity according to the directivity. antenna elements arranged on a predetermined plane so as to extend in a direction perpendicular to the plane; an antenna unit comprising a plurality of parasitic elements arranged to extend in the vertical direction;
a plurality of first adjusters disposed on either one of the upper portion and the lower portion of the antenna portion for adjusting the length of each of the plurality of parasitic elements;
A plurality of second adjusting sections arranged on either the upper or lower side of the antenna section where the first adjusting section is not arranged, and adjusting the length of each of the plurality of parasitic elements together with the first adjusting section. When,
a setting unit that sets the first adjustment unit and the second adjustment unit according to the directivity of the antenna unit;
with
each of the first adjustment unit and the second adjustment unit includes one or more metal members arranged at ends of one or more of the plurality of parasitic elements,
The setting unit selects one set of the first adjustment unit and the second adjustment unit according to the directivity from among the plurality of first adjustment units and the plurality of second adjustment units, An antenna device, wherein the first adjustment section and the second adjustment section are set by rotating around a position where the antenna element is arranged according to the directivity . In the antenna device according to any one of claims 1 to 4,
a receiving unit that receives an electromagnetic wave signal from each of a plurality of communication terminals via the antenna element;
a measurement unit that measures the reception power of each of the received signals of the plurality of communication terminals;
sequentially setting the directivity to each of the plurality of first directivities, and based on the received power measured by the measuring unit in each of the plurality of set first directivities, the plurality of and a control unit that determines the first directivity to be set in the antenna unit among the first directivities, and controls the setting unit to achieve the determined first directivity. Device. In the antenna device according to any one of claims 1 to 4,
a receiving unit that receives an electromagnetic wave signal from each of a plurality of communication terminals via the antenna element;
a measurement unit that measures the reception power of each of the received signals of the plurality of communication terminals;
sequentially setting the directivity to each of a plurality of first directivities, and the received power measured by the measuring unit in each of the plurality of set first directivities, and the plurality of communication terminals; and a cell identifier indicating a cell in which the communication terminal is located, which is included in each of the signals, the first directivity to be set in the antenna unit among the plurality of first directivities is determined and determined An antenna device, further comprising: a control section that controls the setting section so as to achieve the first directivity.

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