Antenna structure and radar device

Abstract

An antenna structure according to the present disclosure comprises: an antenna base board; a reception antenna unit and a transmission antenna unit disposed on a first surface of the antenna base board; a mounting component disposed on a second surface on the back side of the first surface of the antenna base board; a shield case disposed on the second surface so as to cover the mounting component; and a noise countermeasure sheet disposed on one surface of the shield case.

Description

Antenna structure and radar device

[0001] This specification discloses an antenna structure and a radar device.

[0002] Conventionally, a radar device has been proposed that includes, for example, a substrate, a high-frequency IC attached to the substrate, a shield case that houses the high-frequency IC, and a radio wave absorbing and heat-dissipating gel that covers at least a portion of the high-frequency IC and is in contact with the shield case (see, for example, Patent Document 1). In this radar device, the shield case has a convex portion that protrudes toward the high-frequency IC at the portion facing the high-frequency IC, and the radio wave absorbing and heat-dissipating gel is in contact with the convex portion, thereby enabling heat generated by the high-frequency IC to be dissipated and floor noise caused by the high-frequency IC to be suppressed.

[0003] Japanese Patent Application Laid-Open No. 2021-12083

[0004] However, although the above-mentioned radar device is said to be able to suppress floor noise, this is still not sufficient, and there has been a demand for a device that can achieve both detection accuracy and noise countermeasures at a higher level.

[0005] The present disclosure has been made in consideration of such problems, and has as its main object to provide an antenna structure and a radar device that can achieve better noise countermeasures while maintaining detection accuracy.

[0006] The antenna structure and radar device disclosed in this specification employ the following means to achieve the above-mentioned main object.

[0007] The antenna structure of the present disclosure comprises an antenna substrate, a transmitting antenna section and a receiving antenna section disposed on a first surface of the antenna substrate, mounted components disposed on a second surface behind the first surface of the antenna substrate, a shielding case disposed on the second surface so as to cover the mounted components, and a noise reduction sheet disposed on one surface of the shielding case.

[0008] In this antenna structure, a mounted component covered with a shielding case and a noise suppression sheet is disposed on the second surface of the antenna substrate, thereby achieving more effective noise suppression. Furthermore, since the antenna is located on the first surface of the antenna substrate, detection accuracy is maintained. This antenna structure achieves more effective noise suppression while maintaining detection accuracy. Here, the noise suppression sheet may be, for example, a material made of flexible resin blended with a magnetic material such as ferrite.

[0009] 1 is a schematic explanatory diagram showing an example of a work system 10. FIG. 1 is a schematic explanatory diagram showing an example of a radar device 20. FIG. 1 is a schematic explanatory diagram showing an example of a substrate arranged in a housing case 21. FIG. 2 is a perspective view showing an example of a first surface 41 of an antenna structure 40. FIG. 3 is a perspective view showing an example of a second surface 42 of an antenna structure 40. FIG. 4 is a perspective view showing an example of a shielding case 50. FIG. 5 is a schematic explanatory diagram showing an example of an EMC cover 30. FIG. 6 is an explanatory diagram showing the relationship between the wavelength λn of noise and the wavelength λs of radio waves and an opening.

[0010] An embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating an example of a work system 10. FIG. 2 is a schematic diagram illustrating an example of a radar device 20. FIG. 3 is a schematic diagram illustrating an example of a control board 35 and an antenna board 43 disposed in a housing case 21, with FIG. 3A being an assembly diagram of the control board 35 and FIG. 3B being an assembly diagram of the antenna board 43. FIG. 4 is a perspective view illustrating an example of a first surface 41 of an antenna structure 40. FIG. 5 is a perspective view illustrating an example of a second surface 42 of the antenna structure 40. FIG. 6 is a perspective view illustrating an example of a shielding case 50. FIG. 7 is a schematic diagram illustrating an example of an EMC cover 30. FIG. 8 is a diagram illustrating the relationship between the wavelength λn of noise and the wavelength λs of radio waves and an opening, with FIG. 8A being an explanatory diagram of a plate-like member 131 without an opening and FIG. 8B being an explanatory diagram of a plate-like member 31 with an opening.

[0011] The work system 10 includes a plurality of arm robots 12 that perform predetermined tasks on workpieces (workpieces W) and a control device 15 that controls the arm robots 12. The arm robots 12 are configured as devices that perform predetermined tasks on the workpieces W. Examples of the workpieces W include various parts, such as mechanical parts, electrical parts, electronic parts, and chemical parts, as well as food, bio, and biological products. Examples of predetermined tasks include moving tasks for collecting, moving, and placing workpieces from a collection position to a placement position, assembling parts, processing tasks for machining, applying viscous materials, heating, chemical and / or physical processing, and inspection tasks. Examples of assembly tasks include fastening fasteners such as screws and bolts, inserting connectors, routing wiring, fitting parts, attaching components, and holding down workpieces. Examples of processing tasks include grinding, cutting, deformation, connecting, and joining. Examples of viscous materials include adhesives, solder paste, and grease. Examples of inspection work include work to inspect the results of one or more of the above-mentioned work operations, and may involve work to move the workpiece W. The control device 15 is a computer that controls the entire arm robot 12 included in the work system 10. The arm robot 12 is provided with a radar device 20 as a safety sensor that detects surrounding objects. In the work system 10, when the radar device 20 detects an object around the arm robot 12, the control device 15 switches the operation of the arm robot 12 to low-speed operation or stops the arm robot 12 depending on the distance, for example.

[0012] The radar device 20 is a radio wave sensor that detects objects present in a detection area A by transmitting and receiving radio waves. As shown in FIG. 2 , the radar device 20 includes a housing case 21, a housing cover 22, an EMC housing 25, an EMC cover 30, a control board 35, and an antenna structure 40. The housing case 21 houses the components of the radar device 20. The housing case 21 is made of a material that is transparent to radio waves, has a box shape with an opening, and houses the EMC housing 25. The housing case 21 serves as an antenna surface for radio waves, and is therefore made of a resin that is transparent to radio waves. As shown in FIG. 3A , the housing case 21 houses the EMC housing 25 that houses the control board 35. Furthermore, as shown in FIG. 3B , the antenna structure 40 is housed on top of the control board 35. The housing cover 22 is a lid member disposed at the opening of the housing case 21 and closes the opening. The housing cover 22 is made of a material that transmits radio waves because it serves as the antenna surface for radio waves. A grommet 23 for drawing out wiring to the outside is provided on the side of the housing case 21. A USB cover 24 is removably attached to the side of the housing case 21 at a location where a USB connector is connected from the outside.

[0013] The control board 35 is electrically connected to the antenna board 43, and controls the setting of radio wave transmission and reception parameters, the start and end of sensing, and processes signals obtained by the antenna board 43. The control board 35 includes a board main body 36 and a connector 37. The board main body 36 is a plate-shaped member, and various control components are mounted on its first and second surfaces. The connector 37 is disposed on the first surface of the board main body 36, and is connected to a connector 54 disposed on the second surface 42 of the antenna board 43.

[0014] The antenna structure 40 is a structure including an antenna unit 46 that transmits and receives radio waves. As shown in FIGS. 4 to 6 , the antenna structure 40 includes an antenna substrate 43, an antenna unit 46, a shielding case 50, mounted components 53, and a connector 54. The antenna substrate 43 is a flat base material having a first surface 41 and a second surface 42 on the rear side thereof. As shown in FIG. 4 , the antenna unit 46 and a noise reduction sheet 48 are disposed on the first surface 41 of the antenna substrate 43. The antenna unit 46 includes a transmitting antenna unit 44 and a receiving antenna unit 45. The transmitting antenna unit 44 is a device that transmits radio waves. The transmitting antenna unit 44 may be configured with multiple antennas arranged in a planar configuration. The receiving antenna unit 45 is a device that receives radio waves. The receiving antenna unit 45 may be configured with multiple antennas arranged in a planar configuration. The size and number of antennas are selected appropriately depending on the performance required of the radar device 20. The noise countermeasure sheet 48 is a member disposed in an area of ​​the first surface 41 other than the transmitting antenna unit 44 and the receiving antenna unit 45. The noise countermeasure sheet 48 is a member that enhances noise resistance so that the radar device 20 can operate normally even when exposed to external noise. The noise countermeasure sheet 48 may be a member made of, for example, a flexible resin mixed with a magnetic material such as ferrite. The noise countermeasure sheet 48 can further reduce noise penetration into the EMC housing 25 and the effect of noise on the antenna unit 46.

[0015] As shown in FIGS. 5 and 6 , a shield case 50, a noise countermeasure sheet 51, a radio wave absorbing sheet 52, mounted components 53, and a connector 54 are disposed on the second surface 42 of the antenna substrate 43. The shield case 50 is disposed on the second surface 42 so as to cover the mounted components 53 disposed on the second surface 42. The shield case 50 is a metal member that blocks electromagnetic noise by providing EMC protection for the mounted components 53. The shield case 50 includes a rectangular flat plate portion 55 and a standing wall portion 56 formed on the outer periphery of the flat plate portion 55, and has an internal space. The mounted components 53 are housed in this internal space. The shield case 50 is electrically connected to ground. The noise countermeasure sheet 51 is a rectangular sheet disposed on the outer side of the flat plate portion 55, which is one surface of the shield case 50. The noise countermeasure sheet 51 is a member that enhances noise resistance so that the radar device 20 can operate normally even when subjected to external noise, for example. The noise countermeasure sheet 51 may be, for example, a flexible resin mixed with a magnetic material such as ferrite. The noise countermeasure sheet 51 can further reduce noise penetration into the shielding case 50 and the impact of noise on the mounted components 53. The noise countermeasure sheet 51 may be the same material as the noise countermeasure sheet 48, or a different material, but it is preferable that they are the same material. As shown in FIG. 6 , the radio wave absorbing sheet 52 is a sheet disposed inside the flat plate portion 55 of the shielding case 50. The radio wave absorbing sheet 52 is disposed on the back surface of the flat plate portion 55 to which the noise countermeasure sheet 51 is attached. The radio wave absorbing sheet 52 may be disposed on the internal space side of the shielding case 50 and may be a material that absorbs noise radio waves output by the radar device 20. The radio wave absorbing sheet 52 may be, for example, a material containing a magnetic material such as ferrite. The mounted components 53 are components disposed on the second surface 42 of the antenna board 43, which is located on the back side of the first surface 41. This mounted component 53 may be, for example, a radio wave control IC, and controls the transmitting antenna section 44 and the receiving antenna section 45 on the first surface 41 of the antenna board 43 .The antenna board 43 is disposed within the EMC housing 25 and the EMC cover 30 to provide countermeasures against noise radio waves, and the mounted components 53 are further protected against noise radio waves by a shielding case 50, a noise countermeasure sheet 51, and a radio wave absorbing sheet 52. The connector 54 is a member connected to the control board 35 that controls the antenna unit 46, and is disposed outside the shielding case 50 on the second surface 42. The connector 54 is connected to the mounted components 53 via wiring, and electrically connects the control board 35 and the mounted components 53.

[0016] The EMC housing 25 is a member that houses the control board 35 and the antenna structure 40. The EMC housing 25 is a metal member, such as aluminum, that blocks electromagnetic noise as an EMC countermeasure and is provided inside the radar device 20. The EMC housing 25 has a bottom surface 26 that is disposed on the bottom surface of the housing case 21 and a vertical wall portion 27 connected to the bottom surface 26. The radar device 20 has a dual structure that includes the EMC housing 25 that houses the control board 35 and the antenna structure 40 and the housing case 21 that houses the EMC housing 25. The EMC cover 30 is a metal member made of the same material as the EMC housing 25 that blocks electromagnetic noise as an EMC countermeasure and is disposed inside the housing cover 22. The EMC cover 30 is made of a plate-shaped member 31 and is a lid member that is disposed over an opening of the EMC housing 25. The EMC cover 30 has a transmitting opening 32 formed at a position corresponding to the transmitting antenna section 44 of the plate-like member 31, and a receiving opening 33 formed at a position corresponding to the receiving antenna section 45. The EMC housing 25 and the EMC cover 30 are fixed via a conductive packing 28 to ensure electrical continuity. The conductive packing 28 abuts against the edge of the opening of the EMC housing 25 and also abuts against the edge of the back side of the EMC cover 30. The EMC housing 25 and the EMC cover 30 are connected to ground.

[0017] The transmitting aperture 32 is an opening provided in the plate-like member 31, through which radio waves from the antenna unit 46 are transmitted. As shown in FIG. 7 , the transmitting aperture 32 is larger than the transmitting antenna unit 44, and the size of one side is determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. For example, when the frequency fs of the radio waves transmitted and received by the antenna unit 46 is higher than the frequency fn of the noise to be removed, the size of one side of the transmitting aperture 32 may be smaller than the wavelength λn of the noise to be removed and larger than the wavelength λs of the radio waves to be transmitted and received. The size of one side of the transmitting aperture 32 may be smaller than half the wavelength λn of the noise to be removed and greater than twice the wavelength λs of the radio waves to be transmitted and received. Furthermore, when the frequency fs [Hz] of the radio waves transmitted and received by the antenna unit 46 is defined as, the frequency fn [Hz] of the noise to be removed is defined as, and c is the speed of light, the height Ht [mm] and width Wt [mm] of the transmitting aperture 32 may be expressed by the following equations (1) and (2). In this case, the relationship in equation (5) is satisfied, where c = fλ. A transmitting aperture 32 that satisfies this relationship can further suppress the attenuation of the transmitted and received radio waves and reduce noise radio waves.

[0018] The receiving aperture 33 is an opening provided in the plate-like member 31, through which radio waves from the antenna unit 46 are received. The receiving aperture 33 is larger than the receiving antenna unit 45, and the size of one side is determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. For example, when the frequency fs of the transmitted and received radio waves is greater than the frequency fn of the noise to be removed, the size of one side of the receiving aperture 33 may be smaller than the wavelength λn of the noise to be removed and larger than the wavelength λs of the transmitted and received radio waves. The size of one side of the receiving aperture 33 may be less than half the wavelength λn of the noise to be removed and greater than twice the wavelength λs of the transmitted and received radio waves. Furthermore, when the frequency fs [Hz] of the radio waves transmitted and received by the antenna unit 46 is the frequency fn [Hz] of the noise to be removed, and c is the speed of light, the height Hr [mm] and width Wr [mm] of the receiving aperture 33 may be expressed by the following equations (3) and (4): At this time, it is assumed that the relationship of formula (5) is satisfied. The receiving aperture 33 that satisfies this relationship can further suppress the reduction of the transmitted and received radio waves, and can reduce noise radio waves.

[0019]

[0020] Noise suppression measures for electrical devices are important for maintaining the safety and performance of the device. In particular, noise suppression is essential for safety sensors, where detection accuracy is important. Conventional electrical devices often use electromagnetic shields that cover the entire circuit board with a metal plate, as shown in FIG. 8A . However, when using a metal plate-shaped member 131, for example, transmitted radio waves from a radio wave sensor can be immediately reflected by the electromagnetic shield and received by the receiving antenna, generating noise that significantly affects signal strength at close range. In this radar device 20, to achieve both sensor signal strength and noise suppression, an electromagnetic shield structure is used ( FIG. 8B ) using a plate-shaped member 31 with an opening sized to take into account the wavelength λs used and the wavelength λn of the noise to be removed. For example, in one example of the radar device 20, if the frequency fs of the radio waves transmitted and received by the antenna unit 46 is 60 GHz, the wavelength λs of the transmitted and received waves is 5 mm, the frequency fn appearing as noise is 80 to 1000 MHz, and the wavelength λn of the noise is 300 to 3700 mm, then the height Ht and width Wt, and the height Hr and width Wr, will both be in the range of 10 mm to 150 mm. Within this range, the transmitted and received radio waves can be further prevented from being reflected by the electromagnetic wave shield, thereby reducing noise radio waves.

[0021] Next, the operation of the work system 10 configured as described above according to this embodiment, particularly the object detection process around the arm robot 12, will be described. The radar device 20 is activated after the work system 10 is started, transmits radio waves from the transmitting antenna unit 44, and receives reflected radio waves from the receiving antenna unit 45. The radar device 20 detects the position and distance of external objects by transmitting and receiving radio waves via the antenna unit 46. Radar devices generally detect objects by transmitting radio waves, and therefore are designed to easily transmit radio waves. This structure also makes it easy to receive radio waves, which can lead to malfunctions when unwanted radio waves are irradiated from outside. The simplest way to block external radio waves is to shield the antenna with metal, but this also blocks the radio waves emitted by the antenna itself. Furthermore, the presence of metal near the antenna can increase short-range clutter, leading to reduced radar performance. The thicker the metal, the greater the short-range clutter. In this radar device 20, components other than the antenna unit 46 are mounted on the back side of the antenna board 43, and a shielding case 50 made of thin sheet metal is disposed to cover them. A noise suppression sheet 51 is attached to the flat portion 55 of the shielding case 50, thereby enhancing the noise resistance of the thin sheet metal. Furthermore, in the radar device 20, a radio wave absorbing sheet 52 is attached to the inside of the shielding case 50, thereby further minimizing degradation of radar performance. Furthermore, in the radar device 20, a metal EMC housing 25 and an EMC cover 30 are disposed between the housing case 21 and the housing cover 22 and the antenna board 43 as EMC countermeasures. The EMC cover 30 also has a transmission opening 32 and a reception opening 33 to allow radio waves from the antenna unit 46 to pass through. A noise suppression sheet 48 is also disposed on the first surface 41 of the antenna board 43. Mounted components 53 such as a radio wave control IC are disposed on the second surface 42 on the rear side of the antenna substrate 43, and a metal shield case 50 and a noise suppression sheet 51 are provided as EMC countermeasures. In addition, a radio wave absorbing sheet 52 is provided inside the shield case 50, which can suppress radio waves that have leaked from the antenna section 46 to the rear side.The housing case 21 is made of a resin material for radio wave transparency and lightweight design, but the interior of the case is covered with a metal EMC enclosure 25 for EMC protection. Furthermore, when the frequency (GHz) of the radio waves to be transmitted and received is higher than the frequency band (MHz) for EMC protection, the EMC cover 30 is provided with a transmission opening 32 and a reception opening 33 as windows that utilize the difference in wavelength to sufficiently exceed the wavelength λs (several mm) of the transmitted and received radio waves but are smaller than the wavelength λn (several hundred mm) of the noise for EMC protection. This allows the EMC cover 30 to transmit the transmitted and received radio waves while blocking the noise. In this way, the radar device 20 can prevent malfunctions caused by external radio waves while minimizing degradation of radar performance.

[0022] Here, the correspondence between the components of this embodiment and the components of the present invention will be clarified. The antenna structure 40 of this embodiment corresponds to an example of an antenna structure of the present disclosure, the transmitting antenna section 44 corresponds to an example of a transmitting antenna section, the receiving antenna section 45 corresponds to an example of a receiving antenna section, the mounted component 53 corresponds to an example of a mounted component, the shielding case 50 corresponds to an example of a shielding case, and the noise countermeasure sheet 51 corresponds to an example of a noise countermeasure sheet. Furthermore, the radar device 20 corresponds to an example of a radar device, the control board 35 corresponds to an example of a control board, the EMC housing 25 corresponds to an example of an EMC housing, the EMC cover 30 corresponds to an example of an EMC cover, the transmitting opening 32 corresponds to an example of a transmitting opening, the receiving opening 33 corresponds to an example of a receiving opening, the containing case 21 corresponds to an example of a case, and the containing cover 22 corresponds to an example of a cover.

[0023] The antenna structure 40 of the embodiment described above includes an antenna substrate 43, a transmitting antenna section 44 and a receiving antenna section 45 disposed on the first surface 41 of the antenna substrate 43, mounted components 53 disposed on the second surface 42 behind the first surface 41 of the antenna substrate 43, a shield case 50 disposed on the second surface 42 to cover the mounted components 53, and a noise control sheet 51 disposed on one surface of the shield case 50. In this antenna structure 40, the mounted components 53 covered by the shield case 50 and the noise control sheet 51 are disposed on the second surface 42 of the antenna substrate 43, thereby achieving higher noise control. Furthermore, since the antenna section 46 is located on the first surface 41 of the antenna substrate 43, detection accuracy is maintained. In this antenna structure 40, higher noise control can be achieved while maintaining detection accuracy.

[0024] Furthermore, the shielding case 50 has a radio wave absorbing sheet 52 disposed inside thereof, which further reduces the influence of noise entering from the outside on the mounted components 53. Furthermore, the shielding case 50 is electrically connected to ground, which stabilizes the reference voltage of the electronic circuit and further reduces the influence of noise. Furthermore, the antenna board 43 has a noise suppression sheet 48 disposed on the first surface 41 in an area other than the transmitting antenna unit 44 and the receiving antenna unit 45. This antenna structure 40 also provides more effective noise suppression on the first surface 41. The antenna board 43 has a connector 54 disposed on the second surface 42, outside the shielding case 50, which is connected to the control board 35 that processes signals obtained by the transmitting antenna unit 44 and the receiving antenna unit 45. In this antenna structure 40, the connector 54 is located outside the shielding case 50 and can be electrically connected to the control board 35.

[0025] The radar device 20 also includes the above-described antenna structure 40, a control board 35 electrically connected to the antenna board 43, an EMC housing 25 that houses the antenna structure 40 and the control board 35, an EMC cover 30 that has a transmission opening 32 formed at a position corresponding to the transmitting antenna unit 44 and a reception opening 33 formed at a position corresponding to the receiving antenna unit 45 and is disposed on the EMC housing 25, a housing case 21 that is transparent to radio waves and houses the EMC housing 25, and a housing cover 22 that is transparent to radio waves and is disposed on the housing case 21. In this radar device 20, by covering the antenna structure 40 and the control board 35 with the EMC housing 25 and the EMC cover 30, better noise countermeasures can be achieved. In addition, in this radar device 20, by providing openings such as the transmission opening 32 and the reception opening 33 in the EMC cover 30, radio waves other than noise can be transmitted, thereby maintaining detection accuracy. The EMC housing 25 and the EMC cover 30 are fixed via a conductive packing 28 for electrical continuity. In this radar device 20, better noise countermeasures can be achieved by establishing electrical continuity between the EMC housing 25 and the EMC cover 30. Furthermore, since the EMC housing 25 and the EMC cover 30 are made of metal and the housing case 21 and the housing cover 22 are made of resin, the radar device 20 can achieve better noise countermeasures by using the metal EMC housing 25 and the EMC cover 30, and can be provided with strength and radio wave permeability by using the resin housing case 21 and the housing cover 22.

[0026] The radar device 20 also includes the antenna structure 40 described above, and an EMC cover 30 disposed in the EMC housing 25. The EMC cover 30 has a transmitting aperture 32 formed at a position corresponding to the transmitting antenna unit 44 and a receiving aperture 33 formed at a position corresponding to the receiving antenna unit 45. The transmitting aperture 32 is larger than the transmitting antenna unit 44 and has a side size determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. The receiving aperture 33 is larger than the receiving antenna unit 45 and has a side size determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. In this radar device 20, the EMC cover 30 is disposed adjacent to the antenna structure 40, thereby achieving more effective noise countermeasures. In addition, the radar device 20 can transmit and receive radio waves by providing an aperture at a position corresponding to the antenna unit 46. Furthermore, in this radar device 20, apertures such as the transmission aperture 32 and the reception aperture 33 are provided with sizes that take into account the wavelength λs of the transmitted and received signals and the wavelength λn of the noise to be removed, thereby enabling better noise countermeasures while maintaining detection accuracy. Furthermore, in the radar device 20, the frequency fs of the transmitted and received radio waves may be greater than the frequency fn of the noise to be removed, and the transmission aperture 32 and the reception aperture 33 may have a side size that is smaller than the wavelength λn of the noise to be removed and larger than the wavelength λs of the transmitted and received radio waves. In this radar device 20, apertures are provided with sizes that take into account the wavelengths of the transmitted and received signals and the wavelength of the noise to be removed, thereby enabling better noise countermeasures while maintaining detection accuracy. Furthermore, in the radar device 20, the transmission aperture 32 and the reception aperture 33 have a side size that is less than half the wavelength λn of the noise to be removed and greater than twice the wavelength λs of the transmitted and received radio waves. In this radar device 20, apertures with a more appropriate size that takes into account the wavelength of the noise to be removed may be provided, thereby enabling better noise countermeasures. Furthermore, in this radar device 20, an aperture of a more suitable size is provided in consideration of the wavelength λs for transmission and reception, so that higher detection accuracy can be maintained.

[0027] It goes without saying that the present disclosure is not limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present disclosure.

[0028] For example, in the above-described embodiment, the radar device 20 is used in the work system 10, but the present invention is not limited to this, as long as the system uses the radar device 20 that transmits and receives radio waves. In this system, too, by using the antenna structure 40, it is possible to achieve better noise countermeasures while maintaining detection accuracy.

[0029] In the above-described embodiment, the radio wave absorbing sheet 52 is disposed inside the shielding case 50, but this is not particularly limited, and the radio wave absorbing sheet 52 may be omitted. In the antenna structure 40, disposing the radio wave absorbing sheet 52 on the shielding case 50 is preferable as a noise countermeasure. Similarly, in the antenna structure 40, the noise countermeasure sheet 48 is disposed on the first surface 41 of the antenna substrate 43, but this is not particularly limited, and the noise countermeasure sheet 48 may be omitted. In the antenna structure 40, disposing the noise countermeasure sheet 48 on the antenna substrate 43 is preferable as a noise countermeasure.

[0030] In the above-described embodiment, the connector 54 connected to the control board 35 is disposed on the second surface 42 of the antenna board 43, but this is not particularly limited, and the connector 54 may be omitted. Also, in the above-described embodiment, the radar device 20 includes the control board 35 in addition to the antenna structure 40, but this is not particularly limited, and the function of the control board 35 may be provided in the antenna structure 40, and the control board 35 may be omitted.

[0031] In the above-described embodiment, the antenna structure 40 has the mounted components 53 disposed on the second surface 42 and includes the shield case 50 and the noise control sheet 51, but is not limited to this, and the antenna structure 40 may omit the shield case 50 and the noise control sheet 51 as long as it includes the antenna section 46, or the mounted components 53 may not be disposed on the second surface 42. If the radar device 20 also includes the EMC housing 25 and the EMC cover 30, it is possible to achieve higher noise control measures while maintaining detection accuracy.

[0032] In the above-described embodiment, the EMC housing 25 and the EMC cover 30 are disposed via the conductive packing 28, but this is not particularly limited. In this case, the EMC housing 25 and the EMC cover 30 do not need to be electrically connected to the ground.

[0033] In the above-described embodiment, the transmitting aperture 32 is larger than the transmitting antenna unit 44 and has a side size determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. However, this is not limited to this, and the transmitting aperture 32 may have a size that is not based on the relationship between the wavelength λn of the noise and the wavelength λs of the radio waves to be transmitted and received. Furthermore, the receiving aperture 33 is larger than the receiving antenna unit 45 and has a side size determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received. However, this is not limited to this, and the receiving aperture 33 may have a size that is not based on the relationship between the wavelength λn of the noise and the wavelength λs of the radio waves to be transmitted and received. In this radar device 20, if the mounted components 53 are disposed on the second surface 42 of the antenna structure 40 and a shield case 50 is provided, or if the EMC housing 25 and EMC cover 30 are provided, better noise countermeasures can be achieved while maintaining detection accuracy.

[0034] In the above-described embodiment, the transmitting aperture 32 and the receiving aperture 33 have a side size in the range of ½ or less the wavelength λn of the noise to be removed and at least twice the wavelength λs of the radio waves to be transmitted and received. However, this is not particularly limited, and any suitable range may be adopted. For example, the transmitting aperture 32 and the receiving aperture 33 may have a side size in the range of ⅓ or less the wavelength λn of the noise to be removed and at least three times the wavelength λs of the radio waves to be transmitted and received, or in the range of ¼ or less the wavelength λn of the noise to be removed and at least four times the wavelength λs of the radio waves to be transmitted and received. In this radar device 20, the aperture size can be more appropriately adjusted to achieve better noise countermeasures while maintaining detection accuracy.

[0035] In the above-described embodiment, the present disclosure has been described as a radar device 20 having an antenna structure 40, but is not limited to this. For example, the present disclosure may be a radar device 20 having an antenna substrate 43, an EMC housing 25, and an EMC cover 30, or may be a radar device 20 having an antenna substrate 43 and an EMC cover 30 having a transmitting opening 32 and a receiving opening 33.

[0036] Here, the control device and information processing device of the present disclosure may be configured as follows: For example, a radar device of the present disclosure includes: an antenna structure having an antenna substrate on a first surface of which a transmitting antenna section and a receiving antenna section are arranged, an EMC housing that houses the antenna structure, an EMC cover that has a transmitting opening formed at a position corresponding to the transmitting antenna section and a receiving opening formed at a position corresponding to the receiving antenna section and is arranged on the EMC housing, a case that is transparent to radio waves and that houses the EMC housing, and a cover that is transparent to radio waves and is arranged on the case.

[0037] In this radar device, the antenna structure and control board are covered with an EMC housing and an EMC cover, which provides better noise countermeasures. Also, in this radar device, by providing an opening in the EMC cover, radio waves other than noise can pass through, thereby maintaining detection accuracy.

[0038] Alternatively, the radar device of the present disclosure may include an antenna structure having an antenna substrate on a first surface of which a transmitting antenna section and a receiving antenna section are arranged, and an EMC cover arranged on the EMC housing, the EMC cover having a transmitting opening formed at a position corresponding to the transmitting antenna section and a receiving opening formed at a position corresponding to the receiving antenna section, wherein the transmitting opening is larger than the size of the transmitting antenna section and the size of one side is determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received, and the receiving opening is larger than the size of the receiving antenna section and the size of one side is determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received.

[0039] In this radar device, an EMC cover is disposed adjacent to the antenna structure, providing more effective noise countermeasures. Furthermore, in this radar device, an opening is provided at a position corresponding to the antenna, allowing for transmission and reception of radio waves. Furthermore, in this radar device, the opening is sized in consideration of the wavelengths of the transmitted and received signals and the wavelength of the noise to be removed, providing more effective noise countermeasures while maintaining detection accuracy.

[0040] This specification also discloses the technical idea of ​​changing "the antenna structure according to claim 1 or 2" to "the antenna structure according to any one of claims 1 to 3" in claim 4 as originally filed, the technical idea of ​​changing "the antenna structure according to claim 1 or 2" to "the antenna structure according to any one of claims 1 to 4" in claim 5 as originally filed, the technical idea of ​​changing "the antenna structure according to claim 1" to "the antenna structure according to any one of claims 1 to 5" in claim 6 as originally filed, the technical idea of ​​changing "the radar device according to claim 6 or 7" to "the radar device according to any one of claims 6 to 8" in claim 9 as originally filed, the technical idea of ​​changing "the antenna structure according to claim 1" to "the antenna structure according to any one of claims 1 to 5" in claim 10 as originally filed, and the technical idea of ​​changing "the radar device according to claim 10 or 11" to "the radar device according to any one of claims 10 to 12" in claim 13 as originally filed.

[0041] The present disclosure is applicable to technical fields using detection sensors.

[0042] 10 Work system, 12 Arm robot, 15 Control device, 20 Radar device, 21 Storage case, 22 Storage cover, 23 Grommet, 24 USB cover, 25 EMC housing, 26 Bottom surface, 27 Standing wall portion, 28 Conductive packing, 30 EMC cover, 31 Board body, 32 Transmission opening, 33 Reception opening, 35 Control board, 36 Board body, 37 Connector, 40 Antenna structure, 41 First surface, 42 Second surface, 43 Antenna board, 44 Transmission antenna portion, 45 Reception antenna portion, 46 Antenna portion, 48 Noise countermeasure sheet, 50 Shield case, 51 Noise countermeasure sheet, 52 Radio wave absorbing sheet, 53 Mounted component, 54 Connector, 55 Flat plate portion, 56 Standing wall portion, A Detection area, λn Noise wavelength, λs Radio wave wavelength, Ht, Hr Height, Wt, Wr Width, W Work.

Claims

1. An antenna structure comprising: an antenna board; a transmitting antenna section and a receiving antenna section arranged on a first surface of the antenna board; mounted components arranged on a second surface behind the first surface of the antenna board; a shielding case arranged on the second surface so as to cover the mounted components; and a noise suppression sheet arranged on one surface of the shielding case.

2. The antenna structure according to claim 1, wherein the shielding case has an electromagnetic wave absorbing sheet disposed on the inside thereof.

3. The antenna structure according to claim 1 or 2, wherein the shielding case is electrically connected to ground.

4. The antenna structure according to claim 1 or 2, wherein a noise suppression sheet is disposed on the area of ​​the first surface of the antenna substrate other than the transmitting antenna section and the receiving antenna section.

5. The antenna structure according to claim 1 or 2, wherein a connector to which a control board is electrically connected is disposed on the outside of the shield case on the second surface of the antenna board.

6. A radar device comprising: an antenna structure as claimed in claim 1; an EMC housing for accommodating said antenna structure; an EMC cover arranged on said EMC housing, said EMC cover having a transmitting opening formed at a position corresponding to said transmitting antenna section and a receiving opening formed at a position corresponding to said receiving antenna section; a case that is transparent to radio waves and accommodates said EMC housing; and a cover that is transparent to radio waves and arranged on said case.

7. A radar device comprising: an antenna structure having an antenna substrate having a transmitting antenna section and a receiving antenna section disposed on a first surface thereof; an EMC housing for accommodating said antenna structure; an EMC cover disposed on said EMC housing and having a transmitting opening formed at a position corresponding to said transmitting antenna section and a receiving opening formed at a position corresponding to said receiving antenna section; a case that is transparent to radio waves and accommodates said EMC housing; and a cover that is transparent to radio waves and disposed on said case.

8. The radar device according to claim 6 or 7, wherein the EMC housing and the EMC cover are fixed to each other via a conductive packing so as to be electrically conductive.

9. The radar device according to claim 6 or 7, wherein the EMC housing and the EMC cover are made of metal, and the case and the cover are made of resin.

10. A radar device comprising: the antenna structure according to claim 1; and an EMC cover disposed on the EMC housing, the EMC cover having a transmitting opening formed at a position corresponding to the transmitting antenna section and a receiving opening formed at a position corresponding to the receiving antenna section, the transmitting opening being larger than the size of the transmitting antenna section and having a size of one side determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received; and the receiving opening being larger than the size of the receiving antenna section and having a size of one side determined based on the relationship between the wavelength λn of the noise to be removed and the wavelength λs of the radio waves to be transmitted and received.

11. A radar device comprising: an antenna structure having an antenna substrate having a transmitting antenna section and a receiving antenna section disposed on a first surface thereof; and an EMC cover disposed on the EMC housing, the EMC cover having a transmitting opening formed at a position corresponding to the transmitting antenna section and a receiving opening formed at a position corresponding to the receiving antenna section, wherein the transmitting opening is larger than the size of the transmitting antenna section and the size of one side is determined based on the relationship between the wavelength λn of noise to be removed and the wavelength λs of radio waves to be transmitted and received; and the receiving opening is larger than the size of the receiving antenna section and the size of one side is determined based on the relationship between the wavelength λn of noise to be removed and the wavelength λs of radio waves to be transmitted and received.

12. A radar device as described in claim 10 or 11, wherein the frequency of the transmitted and received radio waves is greater than the frequency of the noise to be removed, and the size of one side of the transmitting aperture and the receiving aperture is in a range smaller than the wavelength λn of the noise to be removed and larger than the wavelength λs of the transmitted and received radio waves.

13. A radar device as described in claim 10 or 11, wherein the size of one side of the transmitting aperture and the receiving aperture is in the range of less than 1 / 2 the wavelength λn of the noise to be removed and more than twice the wavelength λs of the radio wave to be transmitted and received.

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