Wireless communication device

Abstract

To realize a wireless communication device that can guarantee the signal quality more fairly to communication partner devices that exist in various directions.SOLUTION: A wireless communication device includes a beamforming antenna, and a beamformer that sets a beam pattern of the beamforming antenna according to an antenna weight vector selected from the beam table. The beam table is a beam table in which the peak directions of the array factors corresponding to the respective antenna weight vectors are non-uniformly distributed in the angular space.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a wireless communication device equipped with a beamforming antenna. [Background technology]

[0002] In order to increase the capacity of wireless communication, the frequency band used is becoming wider and higher in frequency. For example, the millimeter wave band (a frequency band with a frequency of 30 GHz or more and 300 GHz or less) is specified as EHF (Extremely High Frequency) by the ITU (International Telecommunication Union), and the development of wireless communication devices using this band is progressing rapidly. In particular, the 60 GHz band, which overlaps with the oxygen absorption band, has a large propagation loss (and as a result, the propagation distance is short), and is therefore considered an unlicensed frequency band for short-distance communication in many countries. For this reason, the use of the 60 GHz band is being considered in, for example, small cells linked to mobile communication networks, wireless access networks of wireless Internet service providers, or wireless backhaul links such as wireless base stations, wireless relay stations, and public wireless LAN communication access points. In these applications, it is expected that a communication capacity of several Gbps will be realized between wireless communication devices separated by tens to hundreds of meters.

[0003] In wireless communication devices using the millimeter wave band, beam antennas with high gain and sharp directionality are usually used. In particular, in wireless communication devices in which it is assumed that the communication partner device is a mobile terminal or that P2MP (Point To MultiPoint) communication is performed with multiple communication partner devices, beamforming antennas capable of controlling beam patterns are used. In wireless communication devices equipped with beamforming antennas, a configuration is adopted in which the beam pattern of the beamforming antenna is changed according to the direction in which the communication partner device is located. A wireless communication device conforming to IEEE802.11ad is an example of a wireless communication device in which such a configuration is adopted.

[0004] A beamforming antenna is composed of multiple antenna elements. During transmission, a transmission signal split by a splitter has its amplitude and phase adjusted by an amplitude adjuster and a variable phase shifter, and is then input to each antenna element. During reception, a reception signal output from each antenna element has its phase and amplitude adjusted by a variable phase shifter and an amplitude adjuster, and is then combined by a combiner. A wireless communication device equipped with a beamforming antenna controls the beam pattern of the beamforming antenna by controlling the gain of the amplitude adjuster and the phase shift amount of the variable phase shifter corresponding to each antenna element.

[0005] A wireless communication device equipped with a beamforming antenna has a beam table composed of a plurality of antenna weight vectors. Here, the antenna weight vector refers to a vector representing the gain of an amplitude adjuster and the phase shift amount of a variable phase shifter corresponding to each antenna element. When a beamforming antenna is composed of n antenna elements, the antenna weight vector is given by, for example, an n-dimensional complex vector or a 2n-dimensional real vector.

[0006] A wireless communication device equipped with a beamforming antenna sets the gain of an amplitude adjuster and the phase shift amount of a variable phase shifter by referring to an antenna weight vector selected from a beam table. By changing the antenna weight vector selected from the beam table from a first antenna weight vector to a second antenna weight vector, the beam pattern of the beamforming antenna can be changed from a first beam pattern corresponding to the first antenna weight vector to a second beam pattern corresponding to the second antenna weight vector. The beam pattern of a beamforming antenna calculated only from the antenna weight vector is called an array factor. The beam pattern of a beamforming antenna is calculated by multiplying the array factor by the beam pattern of the antenna element.

[0007] Patent Document 1 discloses a technique for updating a beam table. This technique can be applied to a wireless communication device that complies with IEEE802.11ad. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent No. 9,318,805 Summary of the Invention [Problem to be solved by the invention]

[0009] In conventional wireless communication devices, a beam table is used in which the peak directions of the array factors corresponding to each antenna weight vector are uniformly distributed (equally spaced) in the angle space. For this reason, it is difficult to fairly guarantee the signal quality to communication partner devices that exist in various directions. The reason for this will be explained below with reference to a specific example.

[0010] As an example, consider a beam table consisting of 31 antenna weight vectors, designed according to the following guidelines: (1) Assume a beamforming antenna consisting of 16 antenna elements (assuming planar patch antennas) equally spaced (assuming 1 / 2 wavelength spacing) on ​​the same straight line on the same plane. (2) The direction perpendicular to this plane is set to 90°, and 31 target directions are uniformly distributed in directions from 30° to 150°. In other words, the angular intervals of the target directions are uniformly set to (150°-30°) / (31-1)=4°. (3) As the antenna weight vector corresponding to each target direction, select an antenna weight vector that maximizes the gain of the array factor in the target direction from among the antenna weight vectors whose peak directions of the array factors match the target directions with a predetermined accuracy. Below is a list of the peak directions of the array factors of each array antenna weight vector in the beam table designed in this way, and the angular intervals between adjacent peak directions. [Table 1]

[0011] Fig. 7 is a graph (displayed in polar coordinates) showing the array factor corresponding to each antenna weight vector constituting the beam table designed as described above. Fig. 8 is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) showing the envelope of the array factor shown in Fig. 7. Fig. 9 is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) in which the valleys of the array factor shown in Fig. 7 (the minimum points of the envelope shown in Fig. 8) are picked up and plotted. Fig. 10 is a graph (displayed in orthogonal coordinates with the vertical axis representing beam half-width and the horizontal axis representing peak direction) in which the beam half-width of each array factor shown in Fig. 7 is plotted. In addition, when calculating the array factor, the frequency used was set to 60.48 GHz, and the digitization of the variable phase shifter was set to 8 bits (256 steps).

[0012] According to the graph shown in FIG. 8, it can be seen that there exists a direction where the array factor is at a valley, that is, a direction where the gain is inevitably reduced even if the beam pattern of the beamforming antenna is set to a beam pattern corresponding to any antenna weight vector. Also, according to the graph shown in FIG. 9, it can be seen that the gain at the valley of the array factor varies in a range from about 11.5 dB to 11.9 dB, and the fluctuation width is about 0.4 dB. The valley of the array factor where the gain is minimum appears near the 90° direction, which is a direction perpendicular to the plane on which the antenna elements are arranged, and the gain drop at the valley (the difference from the target peak gain of 12 dB) reaches 0.5 dB. Also, according to the graph shown in FIG. 10, it can be seen that the peak direction of the array factor where the beam half width is minimum appears near the 90° direction, which is a direction perpendicular to the plane on which the antenna elements are arranged, just like the valley of the array factor where the gain is minimum.

[0013] The large fluctuation in gain at the valley of the array factor means that the guaranteed radio wave quality varies greatly depending on the direction in which the communication partner device is located. In other words, this means that an unfair situation occurs in which high signal quality can be guaranteed for communication partner devices located in the vicinity of a certain direction (30° and 150° in the above example), while high radio wave quality cannot be guaranteed for communication partner devices located in another direction (near the 90° direction in the above example).

[0014] In addition, when the communication partner device is a mobile terminal, even if the above-mentioned unfairness occurs, the communication partner device is unlikely to suffer serious disadvantages. This is because the communication partner device is unlikely to continue to exist in a direction where a significant drop in gain is unavoidable. On the other hand, when the communication partner device is a fixed terminal, the communication partner device is likely to suffer serious disadvantages if the above-mentioned unfairness occurs. This is because a communication partner device that has once been installed in a direction where a significant drop in gain is unavoidable is likely to continue to exist in that direction thereafter. In addition, examples of disadvantages suffered by the communication partner device include a decrease in communication speed due to a decrease in radio wave quality, which may occur in a wireless communication device that switches MCS (Modulation and Coding Scheme) depending on radio wave quality.

[0015] One aspect of the present invention has been made in consideration of the above circumstances, and provides a wireless communication device that can guarantee signal quality more fairly for communication partner devices that exist in various directions. [Means for solving the problem]

[0016] A wireless communication device according to one embodiment of the present invention comprises a beamforming antenna and a beamformer that sets a beam pattern of the beamforming antenna in accordance with an antenna weight vector selected from a beam table, the beam table being a beam table in which peak directions of array factors corresponding to each antenna weight vector are distributed non-uniformly in angle space. Effect of the Invention

[0017] According to one aspect of the present invention, by using a beam table in which the peak directions of the array factors corresponding to each antenna weight vector are distributed non-uniformly in angle space, it is possible to realize a wireless communication device that can more fairly guarantee signal quality to communication partner devices located in various directions. [Brief description of the drawings]

[0018] [Figure 1]1 is a diagram showing a configuration of a wireless communication system according to an embodiment of the present invention; [Diagram 2] 2 is a block diagram showing a configuration of a first wireless communication device included in the wireless communication system shown in FIG. [Diagram 3] 3 is a graph (shown in polar coordinates) showing array factors corresponding to each antenna weight vector constituting a beam table used by the first wireless communication device shown in FIG. 2. [Figure 4] 4 is a graph showing an envelope of the array factor shown in FIG. 3 (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction). [Diagram 5] This is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) in which the valleys of the array factor shown in FIG. 3 (the minimum points of the envelope shown in FIG. 4) are picked up and plotted. [Figure 6] 4 is a graph plotting the beam half-width of the array factor shown in FIG. 3 (displayed in orthogonal coordinates with the beam half-width on the vertical axis and the peak direction on the horizontal axis). [Figure 7] 1 is a graph (shown in polar coordinates) showing array factors corresponding to each antenna weight vector constituting a beam table used by a conventional wireless communication device. [Figure 8] 8 is a graph showing an envelope of the array factor shown in FIG. 7 (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction). [Figure 9] 8 is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) in which valleys of the array factor shown in FIG. 7 (minimal points of the envelope shown in FIG. 8) are picked up and plotted. [Figure 10] 8 is a graph plotting the beam half-width of the array factor shown in FIG. 7 (displayed in orthogonal coordinates with the beam half-width on the vertical axis and the peak direction on the horizontal axis). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] (Wireless communication systems) The configuration of a wireless communication system S according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing the configuration of the wireless communication system S.

[0020] As shown in FIG. 1, the wireless communication system S includes a first wireless communication device 1 (an example of a "wireless communication device" in the claims) and a second wireless communication device 2 (an example of a "communication partner device" in the claims).

[0021] The first wireless communication device 1 is a wireless communication device connected to an upstream network. As an example, the first wireless communication device 1 is a wireless communication device managed by a wireless Internet service provider. In this case, the first wireless communication device 1 is connected to the Internet (an example of an upstream network) via a provider network, for example. For the connection between the first wireless communication device 1 and the provider network, an optical fiber line, a wireless communication line, or the like is used.

[0022] The second wireless communication device 2 is a wireless communication device connected to a downstream network. As an example, the second wireless communication device 2 is a wireless communication device managed by a user who has a contract with a service provider. In this case, the second wireless communication device 2 is connected to, for example, a local area network (an example of a downstream network) in the user's home.

[0023] 1 illustrates an example in which there is one second wireless communication device 2, but the present invention is not limited to this. For example, there may be two or more second wireless communication devices 2. In this case, each of the two or more second wireless communication devices 2 performs wireless communication with one first wireless communication device 1.

[0024] The first wireless communication device 1 and the second wireless communication device 2 each include a beamforming antenna. The first wireless communication device 1 identifies the direction in which the second wireless communication device 2 exists during the beamforming process, and selects a beam pattern corresponding to the identified direction as a beam pattern of the beamforming antenna included in the first wireless communication device 1. Similarly, the second wireless communication device 2 identifies the direction in which the first wireless communication device 1 exists during the beamforming process, and selects a beam pattern corresponding to the identified direction as a beam pattern of the beamforming antenna included in the second wireless communication device 2. After that, the first wireless communication device 1 and the second wireless communication device 2 each perform wireless communication according to an MCS (Modulation and Coding Scheme) corresponding to the signal quality. For example, when the signal quality is good, high-speed wireless communication is performed, and when the signal quality is poor, low-speed wireless communication is performed.

[0025] The wireless communication system S according to this embodiment is characterized by the beam patterns that the first wireless communication device 1 can select as beam patterns of a beam forming antenna used for wireless communication with the second wireless communication device 2. The beam patterns that the first wireless communication device 1 can select as beam patterns of a beam forming antenna used for wireless communication with the second wireless communication device 2 will be described later with reference to different drawings.

[0026] The first wireless communication device 1 is not limited to a wireless communication device installed by a service provider. Similarly, the second wireless communication device 2 is not limited to a wireless communication device installed by a user who has a contract with a service provider. For example, the first wireless communication device 1 and the second wireless communication device 2 may be wireless communication devices installed by an organization such as a company or a public institution.

[0027] (Configuration of the first wireless communication device) The configuration of the first wireless communication device 1 included in the wireless communication system S will be described with reference to Fig. 2. Fig. 2 is a block diagram showing the configuration of the first wireless communication device 1.

[0028] As shown in FIG. 2, the first wireless communication device 1 includes a BBIC (Base Band Integrated Circuit) 11, an RFIC (Radio Frequency Integrated Circuit) 12, a beamforming antenna 13, a network interface 14, a control system 15, and a power supply unit 16.

[0029] The BBIC 11 is an integrated circuit that processes a BB (Base Band) signal. The RFIC 12 is an integrated circuit that processes an RF (Radio Frequency) signal. The beam forming antenna 13 is an antenna that can set a beam pattern according to an antenna weight vector, and is used for wireless communication with the second wireless communication device 2. In this embodiment, a phased array antenna composed of a plurality of antenna elements is used as the beam forming antenna 13. The network interface 14 is an interface for connecting the wireless communication device 1 to an upstream network. The control system 15 mediates communication between the upstream network connected to the first wireless communication device 1 and the downstream network connected to the second wireless communication device 2 by controlling the BBIC 11 and the RFIC 12. The control system 15 controls the BBIC 11 and the RFIC 12 by referring to various databases according to a given program. The power supply unit 16 supplies power obtained from an external source to each part of the first wireless communication device 1.

[0030] The RFIC 12 includes a LUT (Look Up Table) 121 and a beamformer 122. The LUT 121 stores an antenna weight vector transferred from a storage 151, which will be described later. The beamformer 122 sets a beam pattern of the beamforming antenna 13 according to the antenna weight vector stored in the LUT 121. The beamformer 122 is configured, for example, with an amplitude adjuster in which a gain is set according to the antenna weight vector, and a variable phase shifter in which a phase shift amount is set.

[0031] The control system 15 includes a storage 151. A plurality of antenna weight vectors are stored in the storage 151. As the storage 151, for example, a storage medium such as a hard disk drive (HDD), a solid state drive (SSD), or a flash memory can be used. A non-volatile storage area built in an application specific integrated circuit (ASIC) or a system on a chip (SoC) functioning as the control system 15 may be used as the storage 151. The control system 15 selects one antenna weight vector from the plurality of antenna weight vectors stored in the storage 151, and transfers the selected antenna weight vector to the above-mentioned LUT 121.

[0032] In the following description, a beam pattern corresponding to a certain antenna weight vector refers to a beam pattern of the beamforming antenna 13 obtained when the gain of the amplitude adjuster and the phase shift amount of the variable phase shifter constituting the beamformer 122 are set according to the antenna weight vector. Also, an array factor corresponding to a certain antenna weight vector refers to a beam pattern corresponding to the antenna weight vector when each antenna element is omnidirectional. The beam pattern corresponding to a certain antenna weight vector is calculated by multiplying the array factor corresponding to the antenna weight vector by the beam pattern of each antenna element.

[0033] (Beam table stored in storage) The storage 151 included in the first wireless communication device 1 stores a beam table BT composed of a plurality of antenna weight vectors. The peak directions of the array factors corresponding to the antenna weight vectors constituting the beam table BT are distributed non-uniformly in the angle space (not arranged at equal intervals). As an example, the difference between two adjacent peak directions in the angle space for the array factors corresponding to the antenna weight vectors constituting the beam table BT changes according to the angle difference with the direction perpendicular to the plane on which the antenna elements constituting the beamforming antenna 13 are arranged.

[0034] In the wireless communication device 1 according to this embodiment, the peak directions of the array factors corresponding to the antenna weight vectors constituting the beam table BT are distributed so that they are densest in a direction perpendicular to the plane on which the antenna elements constituting the beam forming antenna 13 are arranged, and are gradually sparser as they move away from that direction. In other words, the peak directions are distributed so that they are densest in a direction in which the beam half-width of the array factors corresponding to the antenna weight vectors constituting the beam table BT is smallest, and are gradually sparser as they move away from that direction. Note that the peak direction being densest in a certain direction is equivalent to the difference between two peak directions adjacent to each other in angle space being smallest in that direction, and the peak direction being gradually sparse is equivalent to the difference between two peak directions adjacent to each other in angle space being gradually larger.

[0035] The first wireless communication device 1 uses such a beam table BT when the direction in which the second wireless communication device 2 exists is not specified. For example, the wireless communication device 1 compatible with IEEE802.11ad uses such a standard beam table SBT in the Sector level sweep (SLS) phase or the Beam Refinement Protocol (BRP) phase, which are performed in a state in which the direction in which the second wireless communication device 2 exists is not specified. At this time, the control system 15 transfers the antenna weight vectors constituting the beam table BT stored in the storage 151 to the LUT 121 of the RFIC 12. Then, the beam former 122 of the RFIC 12 sets the beam pattern of the beam forming antenna 13 according to the antenna weight vectors transferred to the LUT 121 of the RFIC 12.

[0036] As an example, a beam table BT consisting of 31 antenna weight vectors is considered, which is designed according to the following guidelines. (1) A beam forming antenna 13 consisting of 16 antenna elements (assuming planar patch antennas) arranged at equal intervals (assuming 1 / 2 wavelength intervals) on the same straight line on the same plane is assumed, and directions from 30° to 150° are covered, with the direction perpendicular to this plane being the 90° direction. At this time, 31 target directions are distributed non-uniformly so that the gain at the valley of the array factor corresponding to each antenna weight vector is constant. In detail, when 31 target directions are distributed uniformly, the design result of the angle interval of the target directions is uniformly (150°-30°) / (31-1)=4°. Compared with the design result in the case of this uniform distribution, the angle interval of the target directions is adjusted to be wider for directions where the gain at the valley of the array factor is large, and the angle interval of the target directions is adjusted to be narrower for directions where the gain at the valley of the array factor is small, to distribute the target directions. (2) As the antenna weight vector corresponding to each target direction, select the antenna weight vector that maximizes the gain of the array factor in the target direction from among the antenna weight vectors whose array factor peak directions match the target direction with a predetermined accuracy. (3) Examine the design results, and redesign by readjusting the distribution of the target directions until the difference in gain at the valley of the array factor corresponding to each antenna weight vector becomes sufficiently small. Table 2 shows a list of the array factor peak directions of each array antenna weight vector designed in this way and the angle interval between adjacent peak directions. [Table 2]

[0037] FIG. 3 is a graph (displayed in polar coordinates) showing the array factor corresponding to each antenna weight vector constituting the beam table BT designed as above. FIG. 4 is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) showing the envelope of the array factor shown in FIG. 3. FIG. 5 is a graph (displayed in orthogonal coordinates with the vertical axis representing gain and the horizontal axis representing direction) in which the valleys of the array factor shown in FIG. 3 (the minimum points of the envelope shown in FIG. 4) are picked up and plotted. FIG. 6 is a graph (displayed in orthogonal coordinates with the vertical axis representing beam half-width and the horizontal axis representing peak direction) in which the beam half-width of each array factor shown in FIG. 3 is plotted. In addition, when calculating the array factor, the frequency used was set to 60.48 GHz, and the digitization of the variable phase shifter was set to 8 bits (256 steps).

[0038] As shown in Table 2, the peak directions of the array factors corresponding to the antenna weight vectors constituting the beam table BT are distributed most densely in the 90° direction, which is a direction perpendicular to the plane in which the antenna elements constituting the beamforming antenna 13 are arranged, and are distributed so as to become gradually sparser as they move away from that direction. The angle interval of the peak directions near the 90° direction where the peak directions are distributed most densely is 3.3°, and the angle interval of the peak directions near the 30° direction and the 150° direction where the peak directions are distributed most sparsely is 6.0°.

[0039] Comparing the graph shown in FIG. 5 with the graph shown in FIG. 9, the following can be seen. That is, when the conventional beam table is used, the gain at the valley of the array factor fluctuates in the range from about 11.5 dB to 11.9 dB, and the fluctuation range is about 0.4 dB. In contrast, when the beam table BT of this embodiment is used, the gain at the valley of the array factor fluctuates in the range from 11.65 dB to 11.67 dB, and the fluctuation range is 0.02 dB. That is, by using the beam table BT of this embodiment, the fluctuation range of the gain at the valley of the array factor can be reduced. In fact, when the beam table BT of this embodiment is used, the fluctuation range of the gain at the valley of the array factor is negligibly small compared to the gain at the valley of the array factor, and the gain at the valley of the array factor is approximately constant.

[0040] Therefore, according to the first wireless communication device 1 of this embodiment, it is possible to guarantee signal quality more fairly to the second wireless communication devices 2 that exist in various directions.

[0041] If the antenna elements constituting the beamforming antenna 13 are arranged along the x-axis of a Cartesian coordinate system in the xy plane, the 0° direction is the positive x-axis direction, the 90° direction is the positive z-axis direction, the 180° direction is the negative x-axis direction, and the 270° direction is the negative z-axis direction. In this case, the array factor is symmetrical with respect to the xy plane. For this reason, plots from the 180° direction to the 360° direction are omitted in the above-mentioned graph.

[0042] In this embodiment, the beam table BT is stored in the storage 151, but the present invention is not limited to this. The beam table 151 may be stored in a non-volatile storage area built into an ASIC (Application Specific Integrated Circuit) or SoC (System On a Chip) that functions as the control system 15.

[0043] A wireless communication device according to a first aspect of the present invention comprises a beamforming antenna and a beamformer that sets a beam pattern of the beamforming antenna in accordance with an antenna weight vector selected from a beam table, the beam table being a beam table in which peak directions of array factors corresponding to each antenna weight vector are distributed non-uniformly in angle space.

[0044] A wireless communication device according to a second aspect of the present invention may, in addition to the configuration of the wireless communication device according to the first aspect of the present invention, adopt a configuration in which, for the peak directions of the array factors corresponding to each antenna weight vector constituting the beam table, the difference between two adjacent peak directions in angle space changes depending on the difference from the direction perpendicular to the plane in which the antenna elements constituting the beamforming antenna are arranged.

[0045] In a wireless communication device according to a third aspect of the present invention, in addition to the configuration of the wireless communication device according to the second aspect of the present invention, a configuration may be adopted in which, for the peak directions of the array factors corresponding to each antenna weight vector constituting the beam table, the difference between two adjacent peak directions in angle space is minimum in the vicinity of a direction perpendicular to the plane.

[0046] In a wireless communication device according to a fourth aspect of the present invention, in addition to the configuration of the wireless communication device according to the third aspect of the present invention, a configuration may be adopted in which, for the peak directions of the array factors corresponding to each antenna weight vector constituting the beam table, the difference between two adjacent peak directions in angle space gradually increases as the direction moves away from the direction perpendicular to the plane.

[0047] A wireless communication device according to a fifth aspect of the present invention may, in addition to the configuration of the wireless communication device according to the first aspect of the present invention, be configured such that the distribution of peak directions of array factors corresponding to each antenna weight vector constituting the beam table is most dense near the direction in which the beam half-width of the array factor is smallest.

[0048] A wireless communication device according to a sixth aspect of the present invention may adopt, in addition to the configuration of the wireless communication device according to the first aspect of the present invention, a configuration in which the distribution of the peak direction of the array factor corresponding to each antenna weight vector constituting the beam table is set so that the gain at the valley of the array factor is constant.

[0049] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0050] S... Wireless communication system 1... First wireless communication device (wireless communication device) 11... BBIC 12... RFIC 121... LUT 122... Beamformer 13... Beamforming antenna 14... Network interface 15... Control system 151... Storage 16... Power supply unit 2... Second wireless communication device (communication partner device)

Claims

1. A beamforming antenna, a beamformer that sets a beam pattern of the beamforming antenna according to an antenna weight vector selected from a beam table; the beam table is a beam table in which peak directions of array factors corresponding to each antenna weight vector are distributed non-uniformly in an angle space; a difference between two adjacent peak directions of an array factor corresponding to each antenna weight vector constituting the beam table in an angle space varies according to a difference from a direction perpendicular to a plane on which antenna elements constituting the beamforming antenna are arranged; The difference between the two peak directions is smallest in the vicinity of a direction perpendicular to the plane, and gradually increases as the difference moves away from the direction perpendicular to the plane. Wireless communication device.

2. The distribution of the peak directions of the array factors corresponding to the antenna weight vectors constituting the beam table is densest in the vicinity of the direction in which the beam half width of the array factor is smallest. The wireless communication device of claim 1 .

3. A beamforming antenna; a beamformer that sets a beam pattern of the beamforming antenna according to an antenna weight vector selected from a beam table; the beam table is a beam table in which peak directions of array factors corresponding to each antenna weight vector are distributed non-uniformly in an angle space; A distribution of a peak direction of an array factor corresponding to each antenna weight vector constituting the beam table is set so that a gain at a valley of the array factor is constant. Wireless communication device.

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