Wireless communication apparatus and wireless communication system

Abstract

To provide a radio communication device and a radio communication system capable of providing an appropriate service according to a communication partner while suppressing introduction cost.SOLUTION: The wireless communication system 1 includes a wireless communication apparatus 10 and a plurality of wireless devices 20. A radio communication device 10 includes a phased array antenna 11 having a beam forming function, and a control unit 12 that controls a direction of a beam of the phased array antenna 11 and performs control to provide a service according to the direction of the beam of the phased array antenna 11. For example, the wireless communication device 10 is installed in a platform, the wireless device 20 is installed in a train that enters the platform, and the wireless communication device 10 provides a service of displaying, on a monitor provided in the train that enters a track of the platform, an image of the track of the platform that the train enters.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wireless communication device and a wireless communication system. [Background technology]

[0002] A technology has been known in the past that supports the operation of a rolling stock set by presenting an image of the platform to the driver of the rolling stock set. This technology uses a wireless communication system that transmits images captured by a camera installed on the platform to the rolling stock set, receives the transmitted images, and outputs and displays them on a liquid crystal display device installed in the driver's seat of the rolling stock set. For details of such wireless communication systems, see, for example, Patent Documents 1 and 2 listed below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-40544 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-255782 Summary of the Invention [Problem to be solved by the invention]

[0004] However, due to timetable disruptions or maintenance, the relationship between track numbers and entering rolling stock formations is often forced to change. For this reason, in the above-mentioned wireless communication system, it is preferable that the identification settings for communication (e.g., the center frequency and SSID (Service Set Identifier) ​​during wireless communication) be set to the same settings for all rolling stock formations. Therefore, in conventional wireless communication systems, in order to provide appropriate images of rolling stock formations entering the platform track numbers, a separate detection system is required to detect rolling stock formations entering the platform track numbers, which poses a problem of high implementation costs.

[0005] The present invention has been made in view of the above circumstances, and aims to provide a wireless communication device and a wireless communication system that can provide appropriate services according to the communication partner while keeping down the introduction cost. [Means for solving the problem]

[0006] In order to solve the above problems, a wireless communication device (10) according to a first aspect of the present invention includes a phased array antenna (11) having a beamforming function, and a control unit (12) that controls the direction of the beam of the phased array antenna and performs control to provide a service according to the direction of the beam of the phased array antenna.

[0007] A wireless communication device according to a first aspect of the present invention includes a phased array antenna with a beamforming function and a control unit. The control unit controls the beam direction of the phased array antenna according to the position of a wireless device with which the device is communicating, and controls the provision of services according to the beam direction of the phased array antenna. This makes it possible to reduce implementation costs and provide appropriate services according to the communication party.

[0008] Furthermore, a wireless communication device according to a second aspect of the present invention is a wireless communication device according to the first aspect of the present invention, further comprising a beam table (BT) in which first information indicating the beam direction of the phased array antenna is associated with second information regarding the service to be provided, and the control unit controls the beam direction of the phased array antenna using the beam table, and controls the provision of a service according to the controlled beam direction based on the second information associated with the first information indicating the controlled beam direction.

[0009] Furthermore, a wireless communication device according to a third aspect of the present invention is a wireless communication device according to the second aspect of the present invention, which is provided with a plurality of ports (P1, P2) for inputting and / or outputting data according to the service provided, wherein the second information is identification information for identifying the ports, and the control unit controls the data input and output at the ports identified by the identification information associated with the first information indicating the controlled beam direction so that the data is transmitted and received in the direction of the controlled beam.

[0010] Furthermore, a wireless communication device according to a fourth aspect of the present invention is a wireless communication device according to any one of the first to third aspects of the present invention, wherein the beam direction of the phased array antenna is a direction in which a main lobe of the radiation pattern of the phased array antenna appears.

[0011] Furthermore, a wireless communication device according to a fifth aspect of the present invention is a wireless communication device according to any one of the first to fourth aspects of the present invention, in which the control unit controls the beam direction of the phased array antenna so as to maximize the received power of the other device with which wireless communication is performed.

[0012] A wireless communication system (1 to 3) according to a first aspect of the present invention includes a wireless communication device according to any one of the first to fifth aspects of the present invention, and a plurality of wireless devices (20) that communicate wirelessly with the wireless communication device.

[0013] Furthermore, a wireless communication system according to a second aspect of the present invention is a wireless communication system according to the first aspect of the present invention, in which the wireless communication device is installed on a platform (HM), and the wireless equipment is installed on a rolling stock (TR) entering the platform.

[0014] Furthermore, in a wireless communication system according to a third aspect of the present invention, in the wireless communication system according to the second aspect of the present invention, the control unit of the wireless communication device controls the direction of the beam of the phased array antenna so as to enable wireless communication with the wireless equipment installed in the rolling stock set entering a different track on the platform.

[0015] Furthermore, a wireless communication system according to a fourth aspect of the present invention is the wireless communication system according to the second or third aspect of the present invention, in which the wireless communication device provides a service of transmitting an image of the platform corresponding to the platform track number of the rolling stock entering the platform to the rolling stock formation, and the wireless equipment receives the image transmitted from the wireless communication device and outputs it to a display device (40) installed on the rolling stock formation for display. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide an appropriate service according to the communication partner while suppressing the introduction cost. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a block diagram showing a wireless communication system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing an example of a beam table used in the first embodiment of the present invention. [Figure 3] FIG. 2 is a diagram showing an example of a beam formed in the wireless communication system according to the first embodiment of the present invention. [Figure 4] FIG. 10 is a block diagram showing a wireless communication system according to a second embodiment of the present invention. [Figure 5] 10 is a timing chart illustrating the operation of the wireless communication system according to the second embodiment of the present invention. [Figure 6] FIG. 10 is a block diagram showing a wireless communication system according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, a wireless communication device and a wireless communication system according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0019] [First embodiment] Fig. 1 is a block diagram showing a wireless communication system according to a first embodiment of the present invention. As shown in Fig. 1, the wireless communication system 1 of this embodiment includes a wireless communication device 10 and multiple wireless devices 20, and is a system capable of point-to-multipoint communication between the wireless communication device 10 and the multiple wireless devices 20. Such a wireless communication system 1 can provide services according to the wireless devices 20 by wirelessly communicating between the wireless communication device 10 and the multiple wireless devices 20.

[0020] The wireless communication system 1 performs wireless communication using high-frequency signals such as microwaves, quasi-millimeter waves, and millimeter waves. The wireless communication system 1 also performs wireless communication in accordance with the wireless communication standard IEEE802.11ad, for example. The wireless communication device 10 corresponds to a base station device that manages connections, and corresponds to, for example, an AP (Access Point) and a PCP (PBSS Control Point) defined in the wireless communication standard IEEE802.11. The multiple wireless devices 20 correspond to wireless terminals connected to the base station device, and correspond to, for example, STA (STAtion) defined in the wireless communication standard IEEE802.11. Note that, although FIG. 1 shows two wireless devices 20a and 20b as the multiple wireless devices 20, the number of wireless devices 20 is not limited to two. The number of wireless devices 20 may be three or more.

[0021] The wireless communication device 10 includes a phased array antenna 11 and a control unit 12, and provides services according to the direction of the beam BM of the phased array antenna 11. Examples of the services provided by the wireless communication device 10 include providing voice, images, text, graphics, and various other data suitable for the wireless device 20. Note that the services provided by the wireless communication device 10 are not limited to providing the various types of data described above, and may be any service.

[0022] The phased array antenna 11 is an antenna that includes a plurality of antenna elements (not shown) and can freely change its beam pattern (antenna directivity). In other words, the phased array antenna 11 is an antenna that has a beamforming function. The phased array antenna 11 realizes the beamforming function by adjusting at least one of the intensity and phase of signals (transmitted signals) supplied to the plurality of antenna elements or signals (received signals) supplied from the plurality of antenna elements.

[0023] The phased array antenna 11 can form any beam pattern by adjusting the intensity and phase. In this embodiment, for ease of understanding, it is assumed that two beams BM shown in FIG. 1 are formed as the beam pattern of the phased array antenna 11. The direction of the formed beam BM is the direction in which the main lobe of the radiation pattern of the phased array antenna 11 appears. Of the two beams BM, one beam BM1 is directed toward the wireless device 20a, and the other beam BM2 is directed toward the wireless device 20b.

[0024] 1, in this embodiment, the angle of the beam BM emitted from the wireless communication device 10 to the right in the drawing is set to 0°. An angle turning right (clockwise) from this angle (0°) is set to positive, and an angle turning left (counterclockwise) is set to negative. Therefore, the beam BM1 directed toward the wireless device 20a is represented by a negative angle, and the beam BM2 directed toward the wireless device 20b is represented by a positive angle.

[0025] The control unit 12 controls the direction of the beam of the phased array antenna 11 and also controls the provision of services according to the direction of the beam of the phased array antenna 11. Here, the control unit 12 controls the direction of the beam BM of the phased array antenna 11 so as to maximize the received power of the wireless device 20 performing wireless communication. In the example shown in Fig. 1, the control unit 12 controls the direction of the beam BM1 so as to maximize the received power of the wireless device 20a, and controls the direction of the beam BM2 so as to maximize the received power of the wireless device 20b.

[0026] After controlling the direction of the beam BM of the phased array antenna 11, the control unit 12 performs control to provide a service according to the direction of the beam BM of the phased array antenna 11. Specifically, the control unit 12 performs control using a beam table BT in which information indicating the direction of the beam BM of the phased array antenna 11 (first information) is associated with information relating to the service to be provided (second information).

[0027] 2 is a diagram showing an example of a beam table used in the first embodiment of the present invention. As shown in Fig. 2, the beam table BT is a table in which beam sectors (first information), beam directions (first information), and data (second information) are associated with each other.

[0028] The beam sector is information that identifies the beam formed by the phased array antenna 11, and stores, for example, an integer (number) in the range of 0 to 63. The beam direction is information that indicates the direction of the beam BM of the phased array antenna 11, and stores, for example, any angle in the range of -90° to +90°. Note that since there is a one-to-one correspondence between the beam sector and the beam direction, once the beam sector is identified, the beam direction is identified.

[0029] The data is information indicating the data to be used depending on the service to be provided, and for example, data A indicating that the data is to be used in service A, data B indicating that the data is to be used in service B, etc. are stored. If no service is provided, "none" is stored.

[0030] In the example shown in Figure 2, when the beam sector is 10, -35° is stored as the beam direction, and when the beam sector is 25, -10° is stored as the beam direction. When the beam sector is 40, 10° is stored as the beam direction, and when the beam sector is 55, 35° is stored as the beam direction. Note that in the example shown in Figure 2, when the beam sector is other than 10, 25, 40, or 55, the correspondence between the beam sector and the beam direction is not shown.

[0031] In the example shown in Fig. 2, when the beam sector is 10 to 25 (when the beam direction is -35° to -10°), data A is stored as the data. When the beam sector is 40 to 55 (when the beam direction is 10° to 35°), data B is stored as the data. Note that in the example shown in Fig. 2, when the beam sector is 0 to 9, 26 to 39, or 56 to 63, "none" is stored as the data.

[0032] The control unit 12 controls the direction of the beam BM of the phased array antenna 11 using the beam table BT shown in Fig. 2. After controlling the direction of the beam BM of the phased array antenna 11, the control unit 12 performs control to provide a service according to the direction of the controlled beam BM based on data associated with the beam sector that specifies the direction of the beam BM.

[0033] For example, assume that the wireless device 20a is located at a position defined by an angle of -10° relative to the wireless communication device 10, and the wireless device 20b is located at a position defined by an angle of 10° relative to the wireless communication device 10. When the control unit 12 controls the direction of the beam BM of the phased array antenna 11 to a direction specified by the beam sector 25, the control unit 12 performs control to provide data A to the wireless device 20a located in that direction. When the control unit 12 controls the direction of the beam BM of the phased array antenna 11 to a direction specified by the beam sector 40, the control unit 12 performs control to provide data B to the wireless device 20b located in that direction.

[0034] The wireless device 20 is a device that performs wireless communication with the wireless communication device 10. The wireless device 20 may be any device that is capable of wireless communication with the wireless communication device 10. The wireless device 20 includes an antenna and a control unit that controls wireless communication performed with the wireless communication device 10. The antenna included in the wireless device 20 may be any antenna such as a directional antenna or an omnidirectional antenna. Furthermore, the wireless device 20 may include a phased array antenna, similar to the wireless communication device 10.

[0035] The wireless device 20 may be fixedly disposed or movably disposed. When the wireless device 20 is fixedly disposed, the direction of the beam BM formed by the phased array antenna 11 of the wireless communication device 10 does not change. On the other hand, when the wireless device 20 is movably disposed, the direction of the beam BM formed by the phased array antenna 11 of the wireless communication device 10 changes depending on the position of the wireless device 20.

[0036] Here, it is preferable that the wireless device 20 is at least twice the half-width of the beam BM formed by the phased array antenna 11 provided in the wireless communication device 10 in terms of the angular direction relative to the wireless communication device 10. For example, it is preferable that the angle formed between a line passing through the wireless communication device 10 and the wireless device 20a and a line passing through the wireless communication device 10 and the wireless device 20b is at least twice the half-width of the beam BM. This is to prevent unintended data communication.

[0037] 3 is a diagram showing an example of a beam formed in the wireless communication system according to the first embodiment of the present invention. As described above, the direction of the beam BM formed by the phased array antenna 11 is the direction in which the main lobe of the radiation pattern of the phased array antenna 11 appears. The half-width of the beam BM is the angle of the beam BM at the point where the intensity of the beam BM drops by 3 dB from the maximum value of the main lobe.

[0038] Furthermore, when the wireless device 20 is movably disposed, it is preferable to set the movable range of the beam BM formed by the phased array antenna 11 of the wireless communication device 10 to the minimum according to the movable range of the wireless device 20. This is to prevent erroneous detection of the optimal transmission beam sector caused by multipath due to unintended reflections.

[0039] In the example shown in Fig. 2, the movable range of the beam BM is limited to a beam sector range of 10 to 25 (beam direction -35° to -10°) and a beam sector range of 40 to 55 (beam direction 10° to 35°). The movable range of the beam BM may be restricted by the beam sector or by other methods. For example, the movable range of the beam BM may be restricted by adjusting the amount of phase shift set in a phase shifter (not shown) provided corresponding to each of the multiple antenna elements provided in the phased array antenna 11 so that the beam BM is formed only in a specific direction.

[0040] In the above configuration, when the wireless communication device 10 is powered on, the control unit 12 first controls the phased array antenna 11 by referring to the beam table BT shown in FIG. 2 to sequentially change the direction of the beam BM. Then, the control unit 12 controls the direction of the beam BM of the phased array antenna 11 so as to maximize the received power of the wireless device 20 performing wireless communication. In the example shown in FIG. 2, the control unit 12 controls the direction of the beam BM1 so as to maximize the received power of the wireless device 20a, and controls the direction of the beam BM2 so as to maximize the received power of the wireless device 20b. For example, the control unit 12 controls the direction of the beam BM1 to the direction (-10°) specified by the beam sector 25, and controls the direction of the beam BM2 to the direction (10°) specified by the beam sector 40.

[0041] Next, the control unit 12 refers to the beam table BT shown in Fig. 2 and performs control to provide a service according to the direction of the controlled beam BM. For example, the control unit 12 refers to the beam table BT and provides data A corresponding to the direction (-10°) specified by the beam sector 25 to the wireless device 20a located in that direction. Also, the control unit 12 refers to the beam table BT and provides data B corresponding to the direction (10°) specified by the beam sector 40 to the wireless device 20b located in that direction. In this way, a service according to the beam direction of the phased array antenna 11 is provided.

[0042] As described above, in this embodiment, the wireless communication device 10 includes the phased array antenna 11 with a beamforming function and the control unit 12. The control unit 12 controls the direction of the beam BM of the phased array antenna 11 according to the position of the wireless device 20 with which the device is communicating, and performs control to provide a service according to the direction of the beam BM of the phased array antenna 11. This makes it possible to reduce implementation costs and provide an appropriate service according to the device with which the device is communicating.

[0043] Second Embodiment Fig. 4 is a block diagram showing a wireless communication system according to a second embodiment of the present invention. The basic configuration of the wireless communication system 2 of this embodiment is similar to that of the wireless communication system 1 of the first embodiment. Therefore, in Fig. 4, the same components as those shown in Fig. 1 are denoted by the same reference numerals. The wireless communication system 2 of this embodiment is applied to a monitoring system that monitors platform HMs at train stations and the like.

[0044] 4, the wireless communication system 2 of this embodiment includes a wireless communication device 10 and a plurality of wireless devices 20, as well as a plurality of image transmission systems 30 and a plurality of monitors 40 (display devices). The wireless communication device 10 and the plurality of image transmission systems 30 are installed on a station platform HM, and the plurality of wireless devices 20 and monitors 40 are installed on a plurality of electric trains TR (car formations).

[0045] The image transmission system 30 includes a group of cameras 31 and an image synthesizer 32, and images captured by the group of cameras 31 are synthesized by the image synthesizer 32 and transmitted to the wireless communication device 10. In the example shown in FIG. 4, an image transmission system 30a that captures an image of one track number of the platform HM (hereinafter referred to as "track number 1") and an image transmission system 30b that captures an image of the other track number of the platform HM (hereinafter referred to as "track number 2") are provided. Note that, although FIG. 4 shows two image transmission systems 30a and 30b as the multiple image transmission systems 30, the number of image transmission systems 30 is not limited to two. The number of image transmission systems 30 may be three or more.

[0046] The image transmission system 30a includes a camera group 31a and an image composition device 32a. The camera group 31a includes multiple cameras connected by a cable CB1. The multiple cameras included in the camera group 31a are arranged along the platform HM on the track side of the platform HM (along the direction in which the train TR enters the tracks). In other words, the multiple cameras included in the camera group 31a are arranged so as to capture images at different positions on the track side of the platform HM. The image composition device 32a composes (encodes) the images captured by the multiple cameras included in the camera group 31a and transmitted via the cable CB1. The image composition device 32a is connected to port P1 of the wireless communication device 10 and outputs the composed image to the wireless communication device 10.

[0047] The image transmission system 30b includes a camera group 31b and an image composition device 32b. The camera group 31b includes multiple cameras connected by a cable CB2. The multiple cameras included in the camera group 31b are arranged along the platform HM on the second track side of the platform HM (along the direction in which the train TR enters the platform). In other words, the multiple cameras included in the camera group 31b are arranged so as to capture images at different positions on the second track side of the platform HM. The image composition device 32b composes (encodes) the images captured by the multiple cameras included in the camera group 31b and transmitted via the cable CB2. The image composition device 32b is connected to port P2 of the wireless communication device 10 and outputs the composed image to the wireless communication device 10.

[0048] The wireless communication device 10 controls the beam BM1 formed by the phased array antenna 11 so that it is directed toward the wireless device 20a installed on the train TR1 entering track 1 (or the train TR1 departing track 1).The wireless communication device 10 then provides a service of transmitting an image input to the port P1 toward the wireless device 20a located in the direction of the beam BM1.

[0049] In this manner, in this embodiment, port P1 of the wireless communication device 10 is associated with beam BM1 transmitted toward wireless device 20a. That is, in this embodiment, information indicating that data A is data input from port P1 is stored in beam table BT shown in Fig. 2. For example, identification information for identifying port P1 is stored as data A in beam table BT shown in Fig. 2.

[0050] Furthermore, the wireless communication device 10 controls the beam BM2 formed by the phased array antenna 11 so that it is directed toward the wireless device 20b provided on the train TR2 entering track 2 (or the train TR2 departing from track 2).Then, the wireless communication device 10 provides a service of transmitting an image input to the port P2 toward the wireless device 20b located in the direction of the beam BM2.

[0051] In this manner, in this embodiment, port P2 of the wireless communication device 10 is associated with beam BM2 transmitted toward wireless device 20b. That is, in this embodiment, information indicating that data B is data input from port P2 is stored in beam table BT shown in Fig. 2. For example, identification information for identifying port P2 is stored as data B in beam table BT shown in Fig. 2.

[0052] The monitor 40 is equipped with a display device such as a liquid crystal display device, and decodes and displays images received by and output from the wireless device 20. The monitor 40 is installed, for example, in the driver's seat of the train TR. In the example shown in FIG. 4, a monitor 40a is installed on the train TR1 that enters the first track of the platform HM, and a monitor 40b is installed on the train TR2 that enters the second track of the platform HM. Note that although FIG. 4 shows two monitors 40a and 40b as the multiple monitors 40, the number of monitors 40 is not limited to two. The monitor 40 may be installed on all trains TR that are scheduled to enter the platform HM, for example.

[0053] 5 is a timing chart for explaining the operation of the wireless communication system according to the second embodiment of the present invention. For simplicity of explanation, the operation will be explained by taking as an example the case where train TR1 enters platform HM on platform 1 and train TR2 enters platform HM on platform 2 at the same time.

[0054] The wireless communication device 10 broadcasts a beacon at regular time intervals (step S11). When train TR1 enters track one of platform HM and train TR2 enters track two of platform HM, the beacon transmitted from the wireless communication device 10 is received by the wireless device 20a provided on train TR1 and the wireless device 20b provided on train TR2. Upon receiving the beacon, the wireless device 20a and the wireless device 20b confirm the SSID and the like and then transmit an association request to the wireless communication device 10 (step S12).

[0055] When the wireless communication device 10 receives the association requests transmitted from the wireless device 20a and the wireless device 20b, the wireless communication device 10 transmits an ACK (ACKnowledgement) to each of the wireless device 20a and the wireless device 20b (step S13), thereby establishing associations between the wireless communication device 10 and the wireless device 20a and the wireless device 20b.

[0056] Once the association is established, a search for a transmission beam sector is performed between the wireless communication device 10 and the wireless devices 20a and 20b (step S14). For example, if the wireless devices 20a and 20b are also provided with phased array antennas, the wireless communication device 10, the wireless devices 20a and 20b are in a quasi-omnidirectional state during reception and search for a transmission beam sector.

[0057] When the search for the transmission beam sector is completed, the search for the optimal transmission / reception beam sector is performed between the wireless communication device 10 and the wireless devices 20a and 20b (step S15). Specifically, the receiving side is set to the beamforming mode, and a process of searching for the optimal beam sector (beam direction) for transmission and reception is performed.

[0058] The optimal beam sector is a beam sector that maximizes the received power on the wireless devices 20a and 20b side, and is a state in which the transmission and reception beam directions (directions in which the main lobes appear) of the wireless communication device 10 and the wireless devices 20a and 20b are directly opposite to each other. When the optimal transmission and reception beam sector is found, for example, as shown in Fig. 4, the beam BM1 is directed toward the wireless device 20a installed on the train TR1, and the beam BM2 is directed toward the wireless device 20b installed on the train TR2.

[0059] The position of the wireless device 20a changes according to the movement of the train TR1, and the position of the wireless device 20b changes according to the movement of the train TR2. Therefore, the search for the optimal transmitting and receiving beam sector continues at least until the trains TR1 and TR2 stop.

[0060] When the optimal transmitting / receiving beam sector is found, the wireless communication device 10 refers to the beam table BT and transmits data corresponding to the found optimal beam sector as a data frame to each of the wireless devices 20a and 20b (step S16). Specifically, the wireless communication device 10 transmits an image input to port P1 identified by identification information corresponding to the beam sector of beam BM1 (an image output from the image transmission system 30a) toward the wireless device 20a located in the direction of beam BM1. Also, the wireless communication device 10 transmits an image input to port P2 identified by identification information corresponding to the beam sector of beam BM2 (an image output from the image transmission system 30b) toward the wireless device 20b located in the direction of beam BM2.

[0061] When the wireless devices 20a and 20b receive the data frame transmitted from the wireless communication device 10, they transmit an ACK (step S17). Then, the wireless devices 20a and 20b output the received image data to the monitors 40a and 40b, respectively (step S18). As a result, images captured by the camera group 31a of the image transmission system 30a are displayed on the monitor 40a provided on the train TR1, and images captured by the camera group 31b of the image transmission system 30b are displayed on the monitor 40b provided on the train TR2.

[0062] As described above, in this embodiment, the wireless communication device 10 is installed on the platform HM, and the wireless devices 20a and 20b that communicate wirelessly with the wireless communication device 10 are installed on the trains TR1 and TR2, respectively. The wireless communication device 10 controls the direction of the beam BM1 according to the position of the wireless device 20a, and transmits an image captured by the image transmission system 30a (an image of platform HM where train TR1 is entering) to the wireless device 20a, which then displays the image on the monitor 40a. The wireless communication device 10 also controls the direction of the beam BM2 according to the position of the wireless device 20b, and transmits an image captured by the image transmission system 30b (an image of platform HM where train TR2 is entering) to the wireless device 20b, which then displays the image on the monitor 40b.

[0063] In this way, in this embodiment, an image of the platform number of the platform HM into which the train TR is entering can be displayed on the monitor 40 provided on the train TR entering the platform HM, without providing a separate detection system for detecting the train entering the platform HM. In other words, in this embodiment as well, it is possible to provide an appropriate service according to the communication partner while keeping implementation costs down.

[0064] In this embodiment, at the position where the association request is transmitted as shown in FIG. 5, the angle formed by the line passing through the wireless communication device 10 and the wireless device 20a and the line passing through the wireless communication device 10 and the wireless device 20b is preferably at least twice the half-width of the beam BM. This is to prevent unintended data communication. Furthermore, it is preferable to minimize the movable range of the beams BM1 and BM2 formed by the phased array antenna 11 of the wireless communication device 10 according to the movable range of the wireless device 20 installed on the train TR. This is to prevent erroneous detection of the optimal transmission beam sector caused by multipath due to unintended reflections.

[0065] Furthermore, means for detecting the location from which the association request is transmitted may include speed information from the train TR during a stopping operation (slowing down), distance information to the stopping location, GPS (Global Positioning System) signals, etc. The wireless device 10 and the wireless equipment 20 start an association request when they detect the above-mentioned location using these signals.

[0066] Third Embodiment Fig. 6 is a block diagram showing a wireless communication system according to a third embodiment of the present invention. The wireless communication system 3 of this embodiment is basically the same as the wireless communication system 2 of the second embodiment. For this reason, in Fig. 6, the same components as those shown in Fig. 4 are denoted by the same reference numerals. The wireless communication system 3 of this embodiment realizes point-to-multipoint communication between the wireless communication device 10 and wireless devices 20a and 20b by using a VLAN (Virtual Local Area Network), for example, using an L2 bridge.

[0067] 6, the image transmission systems 30a and 30b are connected to ports P1 and P2, respectively, of the wireless communication device 10 via, for example, Ethernet (registered trademark). Also, the monitors 40a and 40b are connected to wireless devices 20a and 20b, respectively, via, for example, Ethernet (registered trademark).

[0068] The wireless communication device 10 includes tag processing units 13a and 13b and a wireless interface unit 14. The tag processing unit 13a is provided between a port P1 and the wireless interface unit 14, and performs tag processing on data (frames) exchanged between the port P1 and the wireless interface unit 14. The tag processing unit 13b is provided between a port P2 and the wireless interface unit 14, and performs tag processing on data (frames) exchanged between the port P2 and the wireless interface unit 14.

[0069] Specifically, the tag processing unit 13a performs a process of inserting a VLAN tag (identifier) ​​into a frame traveling from port P1 to the wireless interface unit 14. The tag processing unit 13a also performs a process of removing a VLAN tag inserted into a frame traveling from the wireless interface unit 14 to port P1. The tag processing unit 13b performs a process of inserting a VLAN tag into a frame traveling from port P2 to the wireless interface unit 14. The tag processing unit 13b also performs a process of removing a VLAN tag inserted into a frame traveling from the wireless interface unit 14 to port P2.

[0070] The VLAN tag processed by tag processing unit 13a (hereinafter referred to as "first VLAN tag") is different from the VLAN tag processed by tag processing unit 13b (hereinafter referred to as "second VLAN tag"). For example, the first VLAN tag is an identifier with a value of "1", and the second VLAN tag is an identifier with a value of "2". In this embodiment, in beam table BT shown in FIG. 2, the first VLAN tag is stored as data A, and the second VLAN tag is stored as data B.

[0071] In this way, in this embodiment, beam sectors and VLAN tags are associated in the beam table BT. Also, when the wireless communication device 10 and the wireless devices 20a and 20b associate with each other, they each acquire the address of the communication partner. The address of the communication partner is a MAC address (Media Access Control address). Therefore, in this embodiment, beam sectors, MAC addresses, and VLAN tags are associated with each other.

[0072] Specifically, the beam sector of beam BM1 (see FIG. 4), the MAC address of wireless interface unit 21a, and the first VLAN tag are associated with each other. Also, the beam sector of beam BM2 (see FIG. 4), the MAC address of wireless interface unit 21b, and the second VLAN tag are associated with each other. In FIG. 6, the MAC address of wireless interface unit 14 is indicated by A0, the MAC address of wireless interface unit 21a is indicated by A1, and the MAC address of wireless interface unit 21b is indicated by A2.

[0073] The wireless interface unit 14 controls the transmission of frames output from the tag processing units 13a and 13b by referring to the beam table BT and the correspondence between MAC addresses. Specifically, the wireless interface unit 14 refers to the beam sector to be transmitted to the wireless interface unit 21a identified by the MAC address. If the referenced beam sector is a value within the range of 10 to 25 shown in FIG. 2, the wireless interface unit 14 controls the transmission so that the frame with the first VLAN tag inserted is transmitted to the wireless interface unit 21a identified by the MAC address. If the referenced beam sector is a value within the range of 40 to 55 shown in FIG. 2, the wireless interface unit 14 controls the transmission so that the frame with the second VLAN tag inserted is transmitted to the wireless interface unit 21a identified by the MAC address.

[0074] Furthermore, the wireless interface unit 14 refers to the beam sector to be transmitted to the wireless interface unit 22b identified by the MAC address. If the referenced beam sector is a value within the range of 10 to 25 shown in Fig. 2, transmission control is performed so that the frame with the first VLAN tag inserted is transmitted to the wireless interface unit 21b identified by the MAC address. If the referenced beam sector is a value within the range of 40 to 55 shown in Fig. 2, transmission control is performed so that the frame with the second VLAN tag inserted is transmitted to the wireless interface unit 21b identified by the MAC address. Note that in the wireless communication device 10, similar to the second embodiment, the directions of the beams BM1 and BM2 are also separately controlled by referring to the beam table BT.

[0075] In this way, similar to the second embodiment, an image captured by the image transmission system 30a is transmitted to the wireless device 20a and displayed on the monitor 40a, and an image captured by the image transmission system 30b is transmitted to the wireless device 20b and displayed on the monitor 40b.

[0076] As described above, in this embodiment, as in the second embodiment, the wireless communication device 10 is installed on the platform HM, and the wireless devices 20a and 20b that communicate wirelessly with the wireless communication device 10 are installed on the trains TR1 and TR2, respectively. The wireless communication device 10 controls the direction of the beam BM1 according to the position of the wireless device 20a, and transmits an image captured by the image transmission system 30a (an image of platform HM where train TR1 is entering) to the wireless device 20a, which then displays the image on the monitor 40a. The wireless communication device 10 also controls the direction of the beam BM2 according to the position of the wireless device 20b, and transmits an image captured by the image transmission system 30b (an image of platform HM where train TR2 is entering) to the wireless device 20b, which then displays the image on the monitor 40b.

[0077] In this way, also in this embodiment, an image of the platform number of the platform HM into which the train TR is entering can be displayed on the monitor 40 provided on the train TR entering the platform HM without providing a separate detection system for detecting the train entering the platform HM. In other words, also in this embodiment, it is possible to provide an appropriate service according to the communication partner while keeping implementation costs down.

[0078] Although the wireless communication device and the wireless communication system according to the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be freely modified within the scope of the present invention. For example, the service provided in the second and third embodiments displays an image of the platform number of the platform HM into which the train TR enters on the monitor 40 provided on the train TR entering the platform number of the platform HM. However, conversely, a service may be provided in which an image of the train TR entering the platform number of the platform HM (for example, an image of the interior of the train TR) is displayed on the monitor provided on each platform HM. [Explanation of symbols]

[0079] 1 to 3...wireless communication system, 10...wireless communication device, 11...phased array antenna, 12...control unit, 20...wireless equipment, 40...monitor, HM...platform, P1, P2...port, BT...beam table, TR...train

Claims

1. a phased array antenna having a beamforming function; a control unit that controls a beam direction of the phased array antenna and controls the provision of a service according to the beam direction of the phased array antenna; A wireless communication device comprising:

2. a beam table in which first information indicating a beam direction of the phased array antenna and second information relating to a service to be provided are associated with each other; The control unit controls a beam direction of the phased array antenna using the beam table, and performs control to provide a service according to the controlled beam direction based on the second information associated with the first information indicating the controlled beam direction. The wireless communication device according to claim 1 .

3. The system has a plurality of ports for inputting and / or outputting data according to the service provided, the second information is identification information for identifying the port, The control unit controls data input / output to / from the port identified by the identification information associated with the first information indicating the controlled beam direction so that the data is transmitted / received in the direction of the controlled beam.

3. The wireless communication device according to claim 2.

4. The wireless communication device according to claim 1 , wherein the beam direction of the phased array antenna is a direction in which a main lobe of a radiation pattern of the phased array antenna appears.

5. The wireless communication device according to claim 1 , wherein the control unit controls the beam direction of the phased array antenna so as to maximize the received power of a counterpart device with which wireless communication is performed.

6. A wireless communication device according to any one of claims 1 to 5; a plurality of wireless devices that wirelessly communicate with the wireless communication device; A wireless communication system comprising:

7. the wireless communication device is installed in a home; The wireless device is installed in a train formation entering the platform.

7. The wireless communication system according to claim 6.

8. 8. The wireless communication system according to claim 7, wherein the control unit of the wireless communication device controls a direction of a beam of the phased array antenna so as to enable wireless communication with the wireless equipment installed in the rolling stock formation entering a different track of the platform.

9. the wireless communication device provides a service of transmitting, to a rolling stock formation entering the platform, an image of the platform corresponding to the track number of the platform into which the rolling stock formation will enter; The wireless device receives the image transmitted from the wireless communication device and outputs it to a display device installed in the rolling stock set for display.

8. The wireless communication system according to claim 7.

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