Antenna device

Abstract

To provide an antenna device capable of performing highly accurate positioning in a wide range while reducing the number of antennas.SOLUTION: The antenna device includes a first antenna, a plurality of second antennas arranged at an equal distance from a predetermined point of the first antenna, and a control unit that performs control to execute three dimensional positioning of a target in a first range by using the first antenna and a first antenna pair including two second antennas and execute three dimensional positioning of a target in a second range at least partially different from the first range by using the first antenna and a second antenna pair including two second antennas at least one of which is different from the antennas included in the first antenna pair.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an antenna device for measuring the position of an object. [Background technology]

[0002] In recent years, communication systems that utilize location information for improved tracking and security have been developed using wireless communication using an extremely wide frequency band known as UWB (Ultra-Wide Band). Ultra-wideband signals, which extend over several hundred megahertz on the frequency axis, can be observed as pulse signals on the time axis, making it possible to identify location information using the time information of the transmission and reception of pulse signals. Location information can be expressed as coordinates on a two- or three-dimensional plane by preparing multiple antennas and calculating the path differences of pulse signals received by the multiple antennas.

[0003] Patent Document 1 discloses a method for controlling window glass or sunroofs of an automobile using a UWB system. In Patent Document 1, the UWB system is used as a pinch prevention function for electric power windows that reduces the occurrence of pinch incidents, and as a vehicle communication function via a user's mobile terminal or vehicle key. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-164404 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because the channel impulse response detects fluctuations in the propagation environment between antennas, it is not suitable for portable devices that are placed in unpredictable environments by users, and triangulation can, in principle, result in false positives if any of the selected antennas are out of line of sight. For this reason, in order to perform positioning over a wide area, it is necessary to deploy multiple antenna sets that combine multiple antennas to avoid out-of-line-of-sight situations, which poses a problem of increasing the number of antennas required.

[0006] Therefore, an object of the present invention is to provide a technology for performing highly accurate positioning over a wide range while reducing the number of antennas. [Means for solving the problem]

[0007] In order to achieve the above object, an antenna device according to one aspect of the present invention comprises: A first antenna; a plurality of second antennas spaced equidistant from a predetermined point on the first antenna; A control unit, performing three-dimensional positioning of an object in a first range using a first antenna pair formed by the first antenna and two of the second antennas; performing three-dimensional positioning of an object in a second range at least partially different from the first range, using a second antenna pair constituted by two second antennas, at least one of which is different from an antenna included in the first antenna pair, and the first antenna; a control unit that performs control as follows: The present invention is characterized by comprising: [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a technology for performing highly accurate positioning over a wide range while reducing the number of antennas. [Brief explanation of the drawings]

[0009] [Figure 1] 1A to 1C are diagrams illustrating the overall configuration of an antenna device according to an embodiment of the present invention. [Figure 2] 1A and 1B are diagrams illustrating the internal configuration of an antenna device according to this embodiment. [Figure 3] FIG. 1 is a diagram showing a communication range of an antenna device according to an embodiment of the present invention; [Figure 4] FIG. 1 is a diagram showing a 2D-AoA positioning range of the antenna device according to the present embodiment; [Figure 5] FIG. 1 is a diagram showing a 3D-AoA positioning range of the antenna device according to the present embodiment; [Figure 6] FIG. 10 is a diagram showing an example of processing executed by the antenna device according to the embodiment; [Figure 7] 1A to 1C are diagrams showing a first state of the antenna device according to the present embodiment. [Figure 8] 1A to 1C are diagrams showing a second state of the antenna device according to the present embodiment. [Figure 9] 10A to 10C are diagrams illustrating a third state of the antenna device according to the present embodiment. [Figure 10] 10A to 10C are diagrams illustrating the overall configuration of an antenna device according to a second embodiment. [Figure 11] FIG. 10 is a diagram showing an example of processing executed by the antenna device according to the second embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0011] First Embodiment The overall configuration of an antenna device 101 according to this embodiment will be described with reference to Figures 1(a) to 1(c). Figure 1(a) is a bird's-eye view of the antenna device 101 from the front direction, and Figure 1(b) is a perspective view of the antenna device 101 in the XZ plane from the front direction, showing only the main functions. Figure 1(c) is a cross-sectional view of the antenna device 101 taken along dotted line 111 in Figure 1(a).

[0012] The antenna device 101 according to this embodiment performs three-dimensional positioning, such as 3D-AoA (3-Dimension-Angle of Arrival), using multiple antennas to locate an object and grasp its relative positional relationship with the object. In the following description, the antenna device 101 is an imaging device equipped with an imaging unit, and is assumed to capture images of the object, a person carrying the object, a vehicle, etc. However, the antenna device 101 does not necessarily have to include an imaging unit. Furthermore, although not shown, signal processing circuits for images and video signals captured by the imaging unit of the antenna device 101 and audio signals acquired from a microphone, power supply functions such as a battery, and a drive system involving the operation of a motor, gears, etc. are included in the antenna device 101.

[0013] Antenna device 101 is composed of drive unit 102 and body unit 103, drive unit 102 and body unit 103 sharing rotation axis 110 which is a straight line passing vertically through the center, and are electrically connected by connection unit 104.

[0014] The drive unit 102 includes an imaging lens 105, a lens drive unit 106, and a first antenna 107 capable of communication compliant with the BLE (Bluetooth Low Energy) standard. The body 103 includes a control board 108, second antennas 109a to 109c for transmitting and receiving signals for UWB positioning, and second antennas 109d to 109f for receiving signals. In the following description, the second antennas 109a to 109c and 109d to 109f may be referred to as second antenna 109 without distinction.

[0015] The first antenna 107 is an antenna capable of transmitting and receiving electromagnetic waves in a horizontal plane (XY plane) in a direction in which the second antenna 109 can transmit and receive electromagnetic waves. In one example, the first antenna 107 is omnidirectional in the horizontal plane. In this case, the first antenna 107 is disposed so that a predetermined point, such as the center point of the first antenna 107, is located on the axis of rotation. In another example, the directivity of the first antenna 107 has a shape that is nearly spherical, and as an example, the first antenna 107 is an inverted-F antenna. However, any type of antenna may be used, such as a patch antenna, a monopole antenna, a dipole antenna, or a loop antenna. In the following description, in this embodiment, the first antenna 107 is described as being provided in the driving unit 102. However, the first antenna 107 may also be provided in the driving unit. The first antenna is capable of communication compliant with UWB communication and the BLE standard. In one example, the first antenna may also be used for communication compliant with other standards, such as the Wi-Fi standard.

[0016] The second antenna 109 is an antenna capable of transmitting electromagnetic waves in a direction away from the rotation axis 110 or receiving electromagnetic waves arriving in the direction of the rotation axis. In this embodiment, the second antenna 109 is described as being a patch antenna, but is not limited to this and may be another type of antenna, such as a waveguide antenna or an antenna with a reflector. In this embodiment, the second antenna 109 has directivity in the XY plane. In one example, the second antenna 109 is positioned so that the main beam with the highest gain is positioned in a direction perpendicular to the rotation axis 110. The second antenna 109 will be described as being capable of UWB communication, but may also be used for BLE-compliant communication or other communication.

[0017] In addition, although the present embodiment has been described assuming that UWB is used as the wideband communication for transmitting and receiving pulse signals, other wideband communication may be used. Similarly, although the present embodiment has been described assuming that BLE is used as the narrowband communication, other narrowband communication may be used.

[0018] A predetermined point, for example, a center point, of each second antenna 109 is disposed so as to be approximately equidistant from a predetermined point of first antenna 107, for example, a point where rotation axis 110 passes through first antenna 107. In one example, the predetermined points of the plurality of second antennas 109 are disposed on the side surface of a cylinder whose central axis is rotation axis 110. In addition, in one example, second antennas 109 are disposed so that the predetermined points of second antennas 109 are located on a circle on the same plane.

[0019] In this embodiment, three-dimensional positioning is performed using a first antenna pair of second antennas 109a and 109d, a second antenna pair of second antennas 109b and 109e, and a third antenna pair of second antennas 109c and 109f, as well as the first antenna 107. For this reason, predetermined points, for example, centers, of the first antenna pair, the second antenna pair, and the third antenna pair may be arranged so as to be approximately equidistant from a predetermined point of the first antenna 107, for example, a point where the rotation axis 110 passes through the first antenna 107. The antenna pair is intended to be used in combination with the first antenna 107 in three-dimensional positioning, which will be described later. For this reason, the directivities of the second antennas 109 included in the antenna pairs must at least partially overlap.

[0020] Note that when three or more second antennas 109 are used in combination with first antenna 107 in three-dimensional positioning, three or more of the second antennas 109 may be used as an antenna group. Also, one of the second antennas 109 may belong to multiple antenna pairs or antenna groups. For example, second antenna 109a may operate as a first antenna pair with second antenna 109d to perform three-dimensional positioning, and may also operate as a second antenna pair with second antenna 109f to perform three-dimensional positioning.

[0021] As shown in FIG. 1( c), second antennas 109a to 109c and second antennas 109d to 109f are arranged on the back side of control board 108 at 120-degree intervals around rotation axis 110. Furthermore, because first antenna 107 is arranged near rotation axis 110, second antenna 109 is arranged to surround rotation axis 110. In other words, second antenna 109 is arranged to be equidistant from rotation axis 110. In one example, antenna 109 is arranged to surround first antenna 107 when viewed in the direction of rotation axis 110. By arranging second antenna 109 in this manner, the range in which first antenna 107 has high gain and the range in which second antenna 109 has high gain can be overlapped. Furthermore, by arranging second antenna 109 so that the distance from first antenna 107 is equidistant, it is possible to prevent variation in the gain of first antenna 107 within the respective communication ranges of multiple antenna pairs. This makes it possible to prevent the second antenna 109 combined with the first antenna 107 from reducing the accuracy of three-dimensional positioning.

[0022] The first antenna pair including second antennas 109a and 109d is arranged so that the direction in which the gain is highest (main beam direction) faces the front direction of the antenna device 101 (downward in FIG. 1(a)). Similarly, the second antenna pair including second antennas 109b and 109e is arranged so that the main beam direction faces the right rear direction of the antenna device 101. Furthermore, the third antenna pair including second antennas 109c and 109f is arranged so that the main beam direction faces the left rear direction of the antenna device 101.

[0023] For example, the second antenna 109 is a patch antenna whose main beam direction is directed away from the rotation axis 110. This configuration enables two-dimensional positioning (2D-Angle of Arrival (2D-AoA)) within a range of ±60 degrees, i.e., 120 degrees, from the main beam direction in the XY plane. Therefore, by combining the first, second, and third antenna pairs, two-dimensional and three-dimensional positioning can be performed 360 degrees around the antenna device 101 in the XY plane. Since positioning accuracy depends on the angle swung left and right toward the main beam direction, the positioning angle may be adjusted depending on the required positioning accuracy. For example, antenna pairs may be densely arranged in directions where positioning accuracy is required, and sparsely arranged in directions where positioning accuracy is not required. Furthermore, if the installation environment of the antenna device 101 is fixed and positioning in a specific direction is not required, an angle at which the antennas are not arranged may be set.

[0024] In one example, in the XY plane, the antenna pair of antennas 109 are arranged so that predetermined points of the antenna pair, for example, the center points, are located at equal intervals on a circle centered on the first antenna 107. Note that in this embodiment, the circle centered on the first antenna 107 is on the XY plane, but is not limited to this. For example, if the first antenna 107 is arranged so as to have omnidirectionality on the XZ plane, the second antenna 109 may be arranged on a circle on the XZ plane.

[0025] 1(c), the second antenna 109 is illustrated as having three antenna pairs, but the number of antenna pairs is not limited to this. In addition, in this embodiment, the first antenna pair, the second antenna pair, and the third antenna pair each use a different second antenna 109. However, it is sufficient that at least one different second antenna 109 is used, and one second antenna 109 may be shared by multiple antenna pairs.

[0026] As shown by the arrow in Figure 1(a), the driver 102 rotates on the body 103 around the rotation axis 110, and the lens driver 106 moves vertically on the body 103 in the direction of the arrow in Figure 1(b), i.e., along the rotation axis 110. Therefore, by aligning the front direction of the imaging lens 105 of the imaging unit with the direction of the subject to be photographed during photography, it is possible to track the subject through a maximum of 360 degrees horizontally and 180 degrees vertically. Note that the lens driver 106 may alternatively or additionally be equipped with a mechanism for adjusting the elevation and depression angles of the imaging lens 105.

[0027] The connecting part 104 with a rotation mechanism not only physically connects the driving part 102 and the body part 103, but also has a rotary connector through which a signal line passes for electrical connection. Note that instead of a rotary connector, a through-hole may be provided through which the signal line can be passed. However, if rotation is limited by the excess length of the signal line, 360 degrees horizontal rotation may be achieved by switching the rotation direction left and right.

[0028] The control board 108 includes a processor and a memory, and operates as a control unit that executes control operations for the entire antenna device 101, including the positioning process described below with reference to Figures 6 and 11. The control board 108 also functions as a drive control unit that controls the rotation of the drive unit 102 along its rotation axis, and a lens drive unit that controls the position and angle of the imaging lens of the imaging unit in the up and down (Z-axis) direction.

[0029] 2(a) and 2(b) are diagrams showing the internal configuration of the antenna device 101 according to this embodiment. Fig. 2(a) is a perspective view of the body part 103 as seen from the direction along the rotation axis (Z-axis direction), and Fig. 2(b) is a perspective view as seen from the front direction of the antenna device 101 (Y-direction).

[0030] In addition to antenna 109, control board 108 includes UWB integrated circuit (IC) 201, control switches 202a to 202c, BLE IC 203, RF (Radio Frequency) line 204, UWB RF line 205, and control line 206. In the figure, solid lines indicate placement on the front side (surface) of control board 108, and dashed lines indicate placement on the back side (back side) or inside (inner layer) of control board 108, but this is not limitative and the placement can be changed as desired.

[0031] Here, the control switch 202a is a single-pole double-throw (SPDT) switch that connects either the UWB IC 201 or the BLE IC 203 to the RF line 204. At this time, the UWB IC 201 and the BLE IC 203 are connected by a control line 206, and the BLE IC 203 controls the control switch 202a via a control line (not shown) by synchronizing the transmission and reception timing of the BLE and UWB. In addition, the BLE IC 203 can transition the operation mode of the UWB IC 201 from a low power consumption state to an active state (hereinafter referred to as wake-up) via the control line 206.

[0032] The control switch 202 b is an SP3T (Single-Pole Triple-Throw) that connects one of the second antennas 109 a , 109 b , and 109 c to the UWB IC 201 via the UWB RF line 205 .

[0033] Similarly, control switch 202c is an SP3T that connects one of second antennas 109d, 109e, and 109f to UWB IC 201 via UWB RF line 205. At this time, UWB IC 201 controls control switches 202b and 202c via a control line (not shown).

[0034] RF line 204 is a wiring having an impedance of 50 ohms, such as a fine coaxial wire, that passes through connection portion 104, and connects first antenna 107 of antenna device 101 to control board 108. UWB RF line 205 is a wiring on or within a board having an impedance of 50 ohms, such as a microstrip line or coplanar line, on control board 108. On the other hand, UWB RF line 205 is also a wiring separated from the board having an impedance of 50 ohms, such as a fine coaxial wire, and connects second antennas 109a to 109f to any of control switches 202a to 202c.

[0035] The second antenna 109 is not limited to a rigid FR-4 PCB (Printed Circuit Board) but may be formed of an FPC (Flexible Printed Circuits) or an MID (Molded Interconnect Device). The connection between the second antenna 109 and the control board 108 is not limited to a fine coaxial wire but may be a stripline or the like. At least one of the second antennas 109 may not be a patch antenna but may be a monopole antenna or an inverted-F antenna.

[0036] FIG. 3 is a diagram showing the distance measurement range in the XY plane of the first antenna 107 of the antenna device 101 according to this embodiment.

[0037] The first antenna 107 is an antenna that can receive electromagnetic waves transmitted toward the antenna device 101 from a communication range 301 capable of communication using BLE or UWB, and can transmit electromagnetic waves from the antenna device 101 in the direction indicated by the communication range 301. The antenna device 101 can perform distance measurement within this communication range 301. In other words, the communication range 301 is the distance measurement range of the antenna device 101. Because the first antenna 107 is omnidirectional in the XY plane, FIG. 3 illustrates the communication range 301 as an area surrounding the entire periphery of the antenna device 101. A predetermined point, such as the center point of the first antenna 107, is located close to the exterior of the antenna device 101 and close to the axis of rotation. Here, if the antenna device 101 is made of metal or conductive resin, placing the first antenna 107 in an opening in the metal or conductive resin can avoid any effect on the antenna characteristics. Whether BLE communication or UWB communication is performed within the communication range 301 is exclusively selected by the control switch 202a. This makes it possible to calculate the distance to an object located within the communication range 301 of the first antenna 107 based on the received signal strength of a predetermined signal, such as a BLE or UWB beacon signal transmitted from the object.

[0038] FIG. 4 is a diagram showing a positioning range on the XY plane of 2D-AoA using the antenna pair of the second antenna 109 of the antenna device 101 according to this embodiment.

[0039] Specifically, in communication range 401, a first antenna pair of second antennas 109a and 109d can communicate using UWB, and in communication range 402, a second antenna group of second antennas 109b and 109e can communicate using UWB. Similarly, in communication range 403, a third antenna group of second antennas 109c and 109f can communicate using UWB. The control switches 202b and 202c exclusively select which of communication ranges 401, 402, and 403 will be used for communication. In any case, the distance and angle of an object can be calculated in two-dimensional coordinates using a two-dimensional positioning method such as 2D-AoA. Note that communication ranges 401, 402, and 403 may at least partially overlap. In this embodiment, the second antenna 109 performs two-dimensional positioning in the XY plane, but this is not limiting and two-dimensional positioning may be performed in any plane.

[0040] Furthermore, the antenna device 101 according to this embodiment has a plurality of antenna pairs. Therefore, in one example, the antenna device 101 may simultaneously perform two-dimensional positioning in a plurality of communication ranges 401 to 403. This allows two-dimensional positioning to be completed in a short time. In one example, the antenna device 101 may perform distance measurement using the first antenna 107, and when it detects based on the distance measurement result that an object exists within the communication range of the first antenna 107, perform two-dimensional positioning using the antenna pairs in the communication ranges 401 to 403.

[0041] FIG. 5 is a diagram showing a positioning range for three-dimensional positioning of the antenna device 101 according to this embodiment.

[0042] Specifically, in communication range 501, first antenna 107 and a second antenna pair of second antennas 109b and 109e are capable of UWB communication, and in this case, either first antenna 107 or second antenna 109b is used for both transmitting and receiving pulse signals. Adding first antenna 107 to the second antenna pair enables positioning in the vertical direction (Z-axis direction), making it possible to calculate the distance and angle of an object in three-dimensional coordinates using 3D-AoA. When the first antenna pair is selected, three-dimensional positioning of the object is performed in a range equivalent to communication range 401 in combination with first antenna 107. Similarly, when the third antenna pair is selected, three-dimensional positioning of the object is performed in a range equivalent to communication range 403 in combination with first antenna 107. In other words, communication ranges 401 to 403 are the positioning range of antenna 101.

[0043] In a use case in which the antenna device 101 captures an image of an object 701, the control board 108 controls the antenna device 101 to take one of the following first to third states in accordance with the trajectory 702 on which the object 701 moves.

[0044] First, the antenna device 101 performs ranging using BLE in a first state (S601 to S604 in FIG. 6). Next, the antenna device 101 performs two-dimensional positioning using 2D-AoA using UWB in a second state (S605 to S607 in FIG. 6). Finally, the antenna device 101 performs three-dimensional positioning using UWB in a third state (S608 to S609 in FIG. 6). Note that in the first state, the first antenna 107 is used to perform ranging. Also, in the second state, one antenna pair of the second antenna 109 is used to perform two-dimensional positioning. Also, in the third state, three-dimensional positioning is performed using one antenna pair of the first antenna 107 and the second antenna 109. Note that two-dimensional positioning or three-dimensional positioning may be performed multiple times while switching the antenna pair of the second antenna 109.

[0045] Fig. 6 is a control sequence showing an example of processing executed by the control board 108 of the antenna device 101 according to this embodiment. The processing in Fig. 6 is realized by the processor of the control board 108 executing a program stored in the memory of the control board 108. Naturally, the control board 108 can also execute other processing such as signal processing of an image or video signal captured by the antenna device 101, signal processing of an audio signal input from a microphone or the like, power management for a battery, and a data management and storage method for RAM, ROM, etc.

[0046] The target object 701 is equipped with wireless communication functions using BLE and UWB. In BLE, the target object 701 acts as a peripheral and intermittently transmits (polls) predetermined signals such as advertising packets. In UWB, the target object 701 acts as a tag. Here, because power consumption and detection probability are mutually exclusive, the target object 701 may dynamically change the interval at which it transmits advertising packets. Note that the target object 701 is assumed to be a human body carrying a portable accessory device (tag) equipped with BLE communication functions and UWB communication functions, but the human body may also be a drone, an automatic guided vehicle, a car, etc.

[0047] The antenna device 101 acts as a BLE central and measures distance based on polling from the target object 701 (S601). Specifically, the BLE IC 203 calculates the distance from the antenna device 101 to the target object 701 from the payload included in the advertisement packet received by the first antenna 107.

[0048] Based on the distance to the object 701, the antenna device 101 determines that the object 701 is close to the antenna device 101 if the distance is within a preset threshold (yes in S602), and connects to the object 701 via BLE communication (S603). The antenna device 101 also wakes up the UWB IC 201 (S604). Here, the BLE IC 203 hands over the address included in the advertisement packet of the object 701 connected via BLE to the UWB IC 201, thereby seamlessly establishing a connection via UWB (S605 and subsequent steps). Note that S602 may be performed multiple times, or thresholds may be set individually depending on the address of the object 701. Note that S603 is not essential, and S604 may also be performed based on the distance measurement result of S602.

[0049] When S601 to S604 are defined as a first state, Figures 7(a) to 7(c) show the configuration of the antenna device 101 in the first state. Figure 7(a) shows the ranging range of the antenna device 101 in the XY plane, Figure 7(b) is a perspective view of the antenna device 101 from the front direction (Y direction), and Figure 7(c) is a perspective view of the antenna device 101 as seen from above, with only the main functions excerpted. Note that components not used for ranging, such as the antenna 109 of the antenna device 101, are omitted.

[0050] 7(a) and 7(b), the BLE IC 203 is connected to the first antenna 107 via the RF line 204 by the control switch 202a. Here, as shown in FIG. 7(a), it is assumed that an object 701 is present within a communication range 301 in which BLE communication is possible. Therefore, as a result of the determination in S602, the antenna device 101 determines that the object 701 is located within the communication range 301 (yes in S602). Note that in FIG. 7(c), the lens driving unit 106 and the imaging lens 105 may be in any position, and may be facing forward (downward in the figure), which is their initial position, for example.

[0051] Next, the antenna device 101 operates as a UWB anchor and performs TWR (Two-Way Ranging) with the object 701, which operates as a UWB tag, to locate the object 701 (S605). Specifically, two-dimensional positioning is performed while sequentially or randomly switching between the first to third antenna pairs, and the distance and angle to the object 701 are calculated using each antenna pair. More precisely, the distance between the antenna device 101 and the object 701 is calculated using TWR, and the angle from the antenna device 101 to the object 701 in a two-dimensional plane is calculated using 2D-AoA. Here, if positioning results to the object 701 are obtained using multiple antenna groups, the positioning result of the antenna group with the closest distance is used (S606), and the antenna device 101 rotates the drive unit 102 toward the front of the closest antenna pair (S607). Note that the method for calculating the distance in two-dimensional positioning is not limited to TWR, and other methods may be used. Also, two-dimensional positioning methods such as SDS-TWR (Symmetrical Double-Sided TWR), TDoA (Time Difference of Arrival), and PDoA (Phase Difference of Arrival) may be combined arbitrarily. When two-dimensional positioning is performed using a positioning method such as PDoA in which the antenna device 101 receives a signal transmitted from the object 701, reception may be performed simultaneously using multiple antenna pairs, and two-dimensional positioning of the object may be performed in parallel using the multiple antenna pairs. This allows two-dimensional positioning using multiple antenna pairs to be completed in a short time.

[0052] If steps S605 to S607 are defined as the second state, Figures 8(a) to 8(c) show the second state of the antenna device 101 according to this embodiment. Figure 8(a) shows the positioning range of the antenna device 101 on the XY plane, Figure 8(b) shows a perspective view of the antenna device 101 from the front direction (Y direction), and Figure 8(c) is a top view of the imaging lens 105 of the antenna device 101, showing only the main components.

[0053] As shown in FIGS. 8(a) and 8(b), the UWB IC 201 is connected to the second antenna 109b via the UWB RF line 205 by the control switch 202b. Similarly, the UWB IC 201 is connected to the second antenna 109e via the UWB RF line 205 by the control switch 202c. It is assumed that the position of the object 701 is within the communication range 402 in which UWB communication is possible. Therefore, in S606, the antenna device 101 can determine that the object 701' is located within the communication range 402 of the second antenna pair based on the positioning result of the second antenna pair. Therefore, as shown in FIG. 8(c), the lens driver 106' and the imaging lens 105' are rotated 120 degrees from their initial positions and point in a rear-right direction (upper right direction in the figure). The rotation direction of the driver 102 may be counterclockwise instead of clockwise. The angle of rotation does not necessarily have to be 120 degrees, and may be set to follow the movement of the object 701 in real time, for example.

[0054] Finally, the antenna device 101, while remaining a UWB anchor, performs new positioning based on the TWR with the target object 701, which is a UWB tag (S608). Specifically, 3D-AoA is performed using the second antenna pair, the first antenna 107 and the second antenna 109, to calculate the distance and angle to the target object 701. Specifically, the distance is calculated using the TWR, and the angle in a three-dimensional plane is calculated using the 3D-AoA. The antenna device 101 rotates the lens driver 106 based on the positioning results. The antenna device 101 also has at least one of a drive mechanism that moves the imaging lens 105 along the Z axis and a mechanism that adjusts the elevation / depression angle of the imaging lens 105. These mechanisms enable the antenna device 101 to orient the front direction of the imaging lens 105 toward the target object 701. The antenna device 101 simply adjusts the front direction of the imaging lens 105 so that the target object 701 is included within the imaging range of the imaging unit.

[0055] If S608 to S609 are defined as a third state, Figures 9(a) to 9(c) show the third state of the antenna device 101 according to this embodiment. Figure 9(a) shows the positioning range of the antenna device 101, Figure 9(b) is a perspective view of the antenna device 101 from the front, and Figure 9(c) is a view of the antenna device 101 as seen from above, with only the main functions being excerpted.

[0056] 9(a) and (b), control switch 202a connects UWB IC 201 to first antenna 107 via RF line 204. However, first antenna 107 is used only for receiving in UWB. Control switch 202b connects UWB IC 201 to second antenna 109b via UWB RF line 205. Similarly, control switch 202c connects UWB IC 201 to second antenna 109e via UWB RF line 205. The position of object 701 is included in communication range 501 in which UWB communication is possible. Also, in FIG. 9(c), lens drive unit 106' remains facing in the rear right direction rotated 120 degrees from the initial position, and imaging lens 105" faces upward (upward in the figure).

[0057] The operations of the lens driving unit 106 and the imaging lens 105 may be linked to signal processing of the video signal. In particular, if the antenna device 101 has an AF (Auto Focus) function, it is conceivable that tracking of the target object 701 by signal processing of the video signal is given priority, and tracking using UWB is used as an auxiliary.

[0058] Furthermore, when there are multiple objects 701, the antenna device 101 may determine the object to track based on address information that is predetermined in association with a priority. Alternatively, the antenna device 101 may track the multiple objects 701 by distinguishing between them by using the median value of the positions at which the multiple objects 701 are located, adjusting the focal length of the imaging lens 105, or the like.

[0059] In addition, the relationship between peripheral and central in BLE and the relationship between anchor and tag in UWB can be interchanged.

[0060] In the third state, the first antenna 107 may be responsible for transmitting UWB advertising packets, and the second antenna 109b may be responsible for receiving them. In this case, the advertising packets transmitted by the first antenna 107 may be received by multiple antenna pairs. This makes it possible to determine the position of the object 701 based on the positioning results of multiple antenna pairs when the detection accuracy of the object 701 is likely to decrease, such as near the edge of the communication range of the antenna pair of antenna 109.

[0061] As shown in FIG. 5, by using the first antenna 107 in common and selecting the first to third antenna pairs, it is possible to use a small number of antennas to create a range equivalent to communication ranges 401 to 403, i.e., a positioning range on a three-dimensional plane that covers the entire periphery of antenna device 101. If the number of antenna pairs, equal to the number of divisions of the positioning range, is N, each antenna pair has two antennas, so antenna device 101 is configured with 2*N+1 antennas. However, by providing an angle at which antennas are not placed, the number may be less than 2*N+1. Reducing the number of antennas is synonymous with reducing the antenna mounting area, which can contribute to a smaller housing size for antenna device 101.

[0062] In addition, each antenna pair is given directionality, which increases the detection accuracy of advertising packets, making it possible to locate the target object with high accuracy.

[0063] As described above, the antenna device according to this embodiment can reduce the antenna mounting area while expanding the imaging area to 360 degrees horizontally and 180 degrees vertically. This makes it possible to realize an antenna device that can detect targets over a wide range with high accuracy while reducing the number of antennas.

[0064] Second Embodiment Figures 10(a) to 10(c) are diagrams showing the overall configuration of an antenna device 101 according to this embodiment. Note that the same components as those in the first embodiment are designated by the same reference numerals and some of the description will be omitted. Figure 10(a) is a bird's-eye view of the antenna device 101 from the front direction, and Figure 10(b) is a perspective view of the antenna device 101 from the front direction, and only the main functions are excerpted.

[0065] The antenna device 101 is composed of a drive unit 102 and a body unit 103. The drive unit 102 and body unit 103 share an axis (dotted line in the figure) that runs vertically through their centers and are electrically connected by a connection unit 104. The drive unit 102 includes an imaging lens 105 and a lens drive unit 106. The body unit 103 includes a control board 108, second antennas 1009a to 1009c that transmit and receive signals for UWB positioning, second antennas 1009d to 1009f that receive signals, and a first antenna 1010 that transmits and receives signals for Wi-Fi communication. In the following description, the second antennas 1009a to 1009f may be referred to as second antenna 1009 without distinction. The second antenna 1009 may have a similar configuration to that of the second antenna 109 described with reference to FIG. 1, except for the arrangement of the second antenna 109.

[0066] The first antenna 1010 is integrated as a wireless module (not shown) equipped with a wireless communication function using Wi-Fi (registered trademark), and the wireless module (not shown) is mounted on the board edge of the control board 108. Note that the first antenna 1010 may have only the antenna function, in which the RF function and the antenna function are configured separately within the wireless module (not shown) and then connected by a thin coaxial cable.

[0067] Here, the driver 102 moves laterally on the body 103 in the direction of the arrow in Figure 10(a), i.e., around the rotation axis, and the lens driver 106 moves vertically on the body 103 in the direction of the arrow in Figure 10(b), i.e., along the rotation axis. Figure 10(c) is a perspective view of the body 103 from the direction of the rotation axis, and shows only the main functions.

[0068] Antenna pairs including two patch antennas, second antenna 1009, are arranged on the rear side of control board 108 at 60-degree intervals around the rotation axis. The first antenna pair, consisting of second antennas 1009a and 1009d, is arranged so that its main beam faces the front of the antenna device (the Y direction in FIG. 1(a)). Similarly, the aperture of the second antenna pair, consisting of second antennas 1009b and 1009e, faces the right front, and the aperture of the third antenna pair, consisting of second antennas 1009c and 1009f, faces the left front. Therefore, by combining the first to third antenna pairs, positioning can be performed within a range of 240 degrees to the left and right of the front of antenna device 101 on the XY plane. That is, for example, if positioning does not need to be performed within a predetermined range, for example, a 120-degree range centered on the rear of antenna device 101 (-Y direction), second antenna 1009 is arranged so as not to overlap with the predetermined range. The predetermined range in which positioning does not need to be performed may partially overlap with the second antenna 1009. For example, in the example of Fig. 10, the range in which positioning is not performed may be a 180-degree range centered on the rear direction of the antenna device 101. This makes it possible to perform highly accurate positioning in the side directions (±X directions) of the antenna device 101, which are the ends of the range in which positioning is performed.

[0069] The first antenna 1010 is arranged to face the front direction (Y direction) of the antenna device 101, and exhibits strong directivity in the front direction of the antenna device 101. In this way, when the antenna device 101 is arranged on a wall surface or the like, an antenna pair does not need to be arranged behind the antenna device 101.

[0070] In a use case in which the antenna device 101 captures an image of an object 701, the antenna device 101 is controlled to take a first state and a third state in accordance with a trajectory 702 along which the object 701 moves.

[0071] First, in a first state, the antenna device 101 performs ranging by BLE using the first antenna 1010 (S1101 to S1105 in FIG. 11). Next, in a third state, the antenna device 101 performs positioning by 3D-AoA using UWB using an antenna pair including the first antenna 1010 and the second antenna 1009 (S1106 to S1108 in FIG. 11).

[0072] 11 shows a control sequence of the antenna device 101 according to the second embodiment. The object 701 has wireless communication functions using Wi-Fi and UWB, and in Wi-Fi, the object 701 acts as a client and receives beacon signals intermittently transmitted from the antenna device 101 (S1101). In UWB communication, the object 701 acts as a tag.

[0073] The antenna device 101 operates as a Wi-Fi access point, and after confirming that it has connected via Wi-Fi to the object 701 that has received the connection request (yes in S1102), it measures the distance based on a predetermined signal strength received from the object 701 (S1103). Specifically, a Wi-Fi IC (not shown) calculates the distance from the antenna device 101 to the object 701 based on the payload included in the packet received by the first antenna 1010. Here, because power consumption and discovery probability are mutually exclusive, the interval at which the object 701 transmits a beacon signal may be dynamically changed.

[0074] If the distance to the object 701 measured in S1103 is within a preset threshold, the antenna device 101 determines that the object 701 has approached the antenna device 101 (yes in S1104), and wakes up the UWB IC 201 (S1105). Here, the Wi-Fi IC (not shown) may hand over the address of the object 701 connected via Wi-Fi to the UWB IC 201. S1101 to S1105 are included in the first state.

[0075] It is also possible to reverse the relationship between clients and access points in Wi-Fi and the relationship between anchors and tags in UWB.

[0076] The antenna device 101 serves as a UWB anchor and performs two-way ranging (TWR) with the target object 701, which is a UWB tag, to determine its position (S1106). Specifically, the first antenna 1010 is combined with the first to third antenna pairs, and 3D-AoA is performed while sequentially or randomly switching between them, thereby calculating the distance and angle to the target object 701 using the first antenna 1010 and one of the antenna pairs. More precisely, the distance is determined by TWR, and the angle from the antenna device 101 to the target object in a three-dimensional plane is determined by 3D-AoA. The antenna device 101 rotates the driver 102 and the lens driver 106 based on the positioning result of the antenna pair closest to the target object 701 (S1107). As a result, the imaging lens 105 faces the target object 701 directly.

[0077] As described above, the antenna device of this embodiment measures the distance to an object, and if it determines that the object is located in the vicinity of the antenna device, it identifies the distance and direction to the object using three-dimensional positioning.

[0078] <Other embodiments> In the present embodiment, the antenna pair including the two second antennas 109 is described as being provided on the body 103 rather than on the drive unit 102 and not rotating in a horizontal plane. However, the antenna pair may be provided on the drive unit 102 and rotate in a horizontal plane. As a result, for example, when the direction from the antenna device 101 to the object 701 is determined as a result of two-dimensional positioning or three-dimensional positioning, the main lobe direction of one of the antenna pairs may be directed toward the object 701. This allows the object 701 to be located more accurately by performing three-dimensional positioning again. In this case, in S607, the main beam direction of the antenna pair having the main beam direction closest to the object 701 may be directed toward the object 701. Alternatively, a predetermined antenna pair having a main beam direction close to the imaging direction of the imaging lens 105, such as the first antenna pair in the case of FIG. 1(c), may be directed toward the object 701.

[0079] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0080] (Summary of the embodiment) The disclosure of this embodiment includes the following antenna device.

[0081] (Item 1) A first antenna; a plurality of second antennas spaced equidistant from a predetermined point on the first antenna; A control unit, performing three-dimensional positioning of an object in a first range using a first antenna pair formed by the first antenna and two of the second antennas; performing three-dimensional positioning of an object in a second range at least partially different from the first range, using a second antenna pair constituted by two second antennas, at least one of which is different from an antenna included in the first antenna pair, and the first antenna; a control unit that performs control as follows: An antenna device comprising:

[0082] (Item 2) 2. The antenna device according to item 1, wherein the plurality of second antennas are arranged on the side of a cylinder having a central axis that is a straight line passing through the predetermined point.

[0083] (Item 3) the control unit performs control to perform three-dimensional positioning of an object in a third range at least partially different from the first range and the second range, using a third antenna pair different from the first antenna pair and the second antenna pair and the first antenna; the two second antennas of the first antenna pair, the two second antennas of the second antenna pair, and the two second antennas of the third antenna pair are different from each other; The antenna device described in item 2 is characterized in that multiple antenna pairs are arranged so that the distance between the first antenna pair and the second antenna pair is equal to the distance between the second antenna pair and the third antenna pair.

[0084] (Item 4) The antenna device described in any one of items 1 to 3, characterized in that the control unit uses the first antenna to measure the distance to an object in a fourth range that includes the first range and the second range.

[0085] (Item 5) The control unit performing two-dimensional positioning using each of the first antenna pair and the second antenna pair of the second antenna; 5. The antenna device according to item 4, wherein it is determined whether to use the first antenna pair or the second antenna pair to perform three-dimensional positioning depending on the result of the two-dimensional positioning.

[0086] (Item 6) 6. The antenna device according to item 5, wherein the control unit determines whether or not to perform the two-dimensional positioning based on a distance measurement result using the first antenna.

[0087] (Item 7) 7. The antenna device according to item 5 or 6, wherein the control unit performs two-dimensional positioning using the first antenna pair and two-dimensional positioning using the second antenna pair in parallel.

[0088] (Item 8) A body portion and a drive unit that rotates along a rotation axis that penetrates the body unit; a drive control unit that controls the rotation of the drive unit; Furthermore, the first antenna is disposed so that the predetermined point is located on the rotation axis; 8. The antenna device according to claim 1, wherein the second antennas have a high gain in a direction away from the axis of rotation.

[0089] (Item 9) The driving unit is provided with an imaging lens, 9. The antenna device according to item 8, wherein the drive control unit directs the imaging lens toward the target object based on the result of the three-dimensional positioning.

[0090] (Item 10) the drive unit further includes a lens drive means for adjusting at least one of the vertical position and the elevation / depression angle of the imaging lens, 10. The antenna device according to item 9, wherein the lens driving means adjusts the front direction of the imaging lens to face the target object based on the result of the three-dimensional positioning.

[0091] (Item 11) a plurality of the second antennas are provided on the driving unit; the control unit performs two-dimensional positioning using each of the first antenna pair and the second antenna pair; The antenna device described in any one of items 8 to 10, characterized in that the drive control unit points the direction in which the gain of either the first antenna pair or the second antenna pair is higher toward the target object depending on the positioning result of the two-dimensional positioning.

[0092] (Item 12) 12. The antenna device according to any one of items 1 to 11, wherein the first antenna is omnidirectional in a predetermined plane.

[0093] (Item 13) Item 13. The antenna device according to item 12, wherein the second antennas are arranged so that when the directivities of the second antennas are superimposed, the result is omnidirectional in the predetermined plane.

[0094] (Item 14) 14. The antenna device according to any one of items 1 to 13, wherein the first antenna and any one of the plurality of second antennas are used for wideband communication.

[0095] (Item 15) 15. The antenna device according to any one of items 1 to 14, wherein the first antenna is also used for narrowband communication.

[0096] (Item 16) 16. The antenna device according to any one of items 1 to 15, wherein the second antenna is arranged so that the direction in which the gain of the second antenna is high does not overlap with the fifth range in which the three-dimensional positioning is not performed.

[0097] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0098] 101: Antenna device, 102: Drive unit, 103: Body unit, 104: Connection unit, 105: Imaging lens, 106: Lens drive unit, 107, 1010: First antenna, 108: Control board, 109, 1009: Second antenna, 201: UWB IC, 202: Control switch, 203: BLE IC, 204: RF line, 205: UWB RF line, 206: Control line, 301, 401, 402, 403, 501: Communication range, 701: Object, 702: Trajectory

Claims

1. A first antenna; a plurality of second antennas spaced equidistant from a predetermined point on the first antenna; A control unit, performing three-dimensional positioning of an object in a first range using a first antenna pair formed by the first antenna and two of the second antennas; performing three-dimensional positioning of an object in a second range at least partially different from the first range, using a second antenna pair constituted by two second antennas, at least one of which is different from an antenna included in the first antenna pair, and the first antenna; a control unit that performs control as follows: An antenna device comprising:

2. 2. The antenna device according to claim 1, wherein the second antennas are arranged on a side surface of a cylinder having a central axis that is a straight line passing through the predetermined point.

3. the control unit performs control to perform three-dimensional positioning of an object in a third range at least partially different from the first range and the second range, using a third antenna pair different from the first antenna pair and the second antenna pair and the first antenna; the two second antennas of the first antenna pair, the two second antennas of the second antenna pair, and the two second antennas of the third antenna pair are different from each other; 3. The antenna device according to claim 2, wherein the first pair of antennas, the second pair of antennas, and the third pair of antennas are arranged at equal intervals on a side surface of the cylinder.

4. The antenna device according to claim 1 , wherein the control unit uses the first antenna to measure the distance to an object in a fourth range that includes the first range and the second range.

5. The control unit performing two-dimensional positioning using each of the first antenna pair and the second antenna pair of the second antenna; 5. The antenna device according to claim 4, wherein whether to use the first antenna pair or the second antenna pair to perform three-dimensional positioning is determined depending on the result of the two-dimensional positioning.

6. The antenna device according to claim 5 , wherein the control unit determines whether or not to perform the two-dimensional positioning based on a result of distance measurement using the first antenna.

7. The antenna device according to claim 5 , wherein the control unit executes two-dimensional positioning using the first antenna pair and two-dimensional positioning using the second antenna pair in parallel.

8. A body portion and a drive unit that rotates along a rotation axis that penetrates the body unit; a drive control unit that controls the rotation of the drive unit; Furthermore, the first antenna is disposed so that the predetermined point is located on the rotation axis; 2. The antenna device according to claim 1, wherein the second antennas have a high gain in a direction away from the rotation axis.

9. The driving unit is provided with an imaging lens, The antenna device according to claim 8 , wherein the drive control unit directs the imaging lens toward the target object based on the result of the three-dimensional positioning.

10. the drive unit further includes a lens drive means for adjusting at least one of the vertical position and the elevation / depression angle of the imaging lens, 10. The antenna device according to claim 9, wherein the lens driving means adjusts the front direction of the imaging lens so as to face the target object based on the result of the three-dimensional positioning.

11. a plurality of the second antennas are provided on the driving unit; the control unit performs two-dimensional positioning using each of the first antenna pair and the second antenna pair; The antenna device according to claim 8, wherein the drive control unit directs either the first antenna pair or the second antenna pair in a direction in which a gain of the first antenna pair is higher toward the target object, depending on the positioning result of the two-dimensional positioning.

12. 2. The antenna device according to claim 1, wherein the first antenna is omnidirectional in a predetermined plane.

13. 13. The antenna device according to claim 12, wherein the second antennas are arranged so that when the directivities of the second antennas are superimposed, the result is omnidirectional in the predetermined plane.

14. 2. The antenna device according to claim 1, wherein the first antenna and any one of the plurality of second antennas are used for wideband communication.

15. 2. The antenna device according to claim 1, wherein the first antenna is also used for narrowband communication.

16. 2. The antenna device according to claim 1, wherein the second antenna is arranged so that a direction in which the gain of the second antenna is high does not overlap with a fifth range in which the three-dimensional positioning is not performed.

Images