Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/30—Arrangements for providing operation on different wavebands
  • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
  • H01Q5/342—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes
  • H01Q5/357—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes using a single feed point
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/12—Supports; Mounting means
  • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
  • H01Q1/2291—Supports; Mounting means by structural association with other equipment or articles used in bluetooth or WI-FI devices of Wireless Local Area Networks [WLAN]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/12—Supports; Mounting means
  • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
  • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
  • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
  • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/48—Earthing means; Earth screens; Counterpoises
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/50—Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/10—Resonant antennas
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/20—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements characterised by the operating wavebands
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/30—Arrangements for providing operation on different wavebands
  • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
  • H01Q5/314—Individual or coupled radiating elements, each element being fed in an unspecified way using frequency dependent circuits or components, e.g. trap circuits or capacitors
  • H01Q5/328—Individual or coupled radiating elements, each element being fed in an unspecified way using frequency dependent circuits or components, e.g. trap circuits or capacitors between a radiating element and ground
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
  • H01Q5/50—Feeding or matching arrangements for broad-band or multi-band operation
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
  • H01Q9/04—Resonant antennas
  • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
  • H01Q9/0421—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with a shorting wall or a shorting pin at one end of the element
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
  • H01Q9/04—Resonant antennas
  • H01Q9/30—Resonant antennas with feed to end of elongated active element, e.g. unipole
  • H01Q9/42—Resonant antennas with feed to end of elongated active element, e.g. unipole with folded element, the folded parts being spaced apart a small fraction of the operating wavelength
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q13/00—Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
  • H01Q13/10—Resonant slot antennas

Definitions

• the invention relates to an antenna for transmitting or receiving radio signals, which antenna can be implemented on a printed circuit board.
• An electronic device that is set up to communicate via a wireless communication network typically comprises at least one antenna for receiving and / or transmitting radio signals.
• the electronic device can be set up to receive or transmit radio signals over a large number of different frequency bands, in particular over two different frequency bands or frequency ranges.
• the device can comprise a multi-band antenna, in particular a dual-band antenna.
• Exemplary dual band antennas can e.g. for the frequency bands 2.4 - 2.5 GHz and 5.1 - 5.8 GHz, i.e. for WLAN (Wireless Local Area Network).
• Antennas typically require a reference ground or reference plane for their function.
• the size and shape of such a reference ground typically have a significant influence on the function and radiation characteristics of an antenna.
• an antenna should be used as a circuit card structure or as a metal structure (e.g. as a stamped and bent part) in circuit cards of different sizes.
• the differently sized circuit boards represent differently developed reference grounds for an antenna.
• plastic in the vicinity of the antenna e.g. due to a housing
• a new antenna tuning is typically required for each printed circuit board geometry and / or application. Such antenna tuning can be achieved by changing the antenna structure and / or by using a so-called “matching circuit”.
• the present document is concerned with the technical task of providing a (dual-band) antenna that can be integrated in an efficient manner (in particular without the need for dedicated antenna tuning) on printed circuit boards of different designs.
• the task is solved by the independent claim.
• Advantageous embodiments are described, inter alia, in the dependent claims.
• a circuit board antenna is described.
• the circuit board antenna described in this document can be implemented in an efficient manner on circuit boards of different dimensions and / or in different environments or applications.
• a printed circuit board typically comprises an electrically conductive (first) outer layer (e.g. a front layer) and an electrically conductive further (second) outer layer (e.g. a lower layer).
• the one or more layers can be electrically isolated from one another by one or more dielectric layers.
• the layers can be an electrically conductive material,
• the electrically conductive material can be removed from the respective layer at least in some areas, in particular in order to form a free space between an antenna structure and a reference area.
• the circuit board antenna comprises an electrically conductive antenna structure on the (first) outer layer of the circuit board.
• the antenna structure can have an elongated shape (e.g. like a dipole antenna).
• the antenna structure can form an inverted-F antenna.
• the antenna structure can have a first
• the antenna structure can be designed to form a first antenna for a first frequency range around the first resonance frequency.
• the first frequency range can in particular comprise 5.1-5.8 GHz or
• the circuit board antenna has an electrically conductive reference area on the outer layer.
• the reference area can be connected in an electrically conductive manner to a ground or to the ground of the printed circuit board.
• the reference area can be designed to form a reference ground for the antenna structure, so that the printed circuit board antenna is independent of a size of the reference ground.
• the printed circuit board antenna has an electrically conductive feed line to the antenna structure.
• the feed line can be substantially perpendicular to the
• Radio signal can be decoupled via the feed line.
• a radio signal to be transmitted by the antenna structure can be fed into the antenna structure via the feed line.
• the reference area can be designed to partially or completely enclose the antenna structure apart from an insulating feed recess for the feed line and apart from an insulating web recess.
• the web recess on a side facing away from the feed line can
• the reference area can thus be divided into (possibly exactly) two parts by the two recesses, i.e. into a first sub-reference area and into a second sub-reference area.
• the reference area in particular the first partial reference area, can have a reference area web on the side of the antenna structure facing away from the feed line.
• the reference area web can be connected to the first sub-reference area in an electrically conductive manner.
• the reference area web can form a resonator capacitively coupled to the antenna structure with a second resonance frequency.
• the reference area web can have an elongated shape (and thus form a dipole antenna, for example).
• the reference area bar can be designed to form a second antenna for a second frequency range around the second resonance frequency.
• the second frequency range can in particular comprise 2.4-2.5 GHz or correspond to this frequency interval.
• a dual-band antenna is thus described which, by providing a reference area and an additional reference area web, can be used in a reliable manner in different installation environments and / or on different types of printed circuit boards.
• the antenna structure can be constructed essentially rectangular.
• the antenna structure can have an electrically conductive rectangle (for providing the antenna function).
• the length of the antenna structure running perpendicular to the feed line can be greater than the width of the antenna structure running parallel to the feed line. Furthermore, the long edge of the
• Reference area ridge parallel to that along the length of the antenna structure extending longitudinal edge of the antenna structure.
• Reference area web and the antenna structure are effected.
• the reference region web and the antenna structure can be capacitively coupled to one another via an electrically insulating free space arranged between the longitudinal edge of the antenna structure and the longitudinal edge of the reference region web.
• the free space between the longitudinal edge of the antenna structure and the longitudinal edge of the reference area web can have a width of F * 2.2 mm ⁇ 10%, where F is any real-valued scaling factor, with
• the antenna structure can be a certain length along the longitudinal edge of the
• the length of the antenna structure depending on the first resonance frequency.
• the adjustment of the length of the antenna structure depending on the first resonance frequency.
• Antenna structure can typically be used to set the first resonance frequency.
• the length of the antenna structure F * 11.4 mm ⁇ 10%.
• the width of the antenna structure is F * 2.4 mm ⁇ 10%.
• the reference region bar has a certain length along a longitudinal edge of the reference region bar, the length of the reference region bar typically depending on the second resonance frequency.
• the adjustment of the length of the reference area web can be used to adjust the second resonance frequency.
• the length of the reference area web can be used to adjust the second resonance frequency.
• the antenna structure can be connected in an electrically conductive manner to the reference area, in particular to the second partial reference area of the reference area, via an electrically conductive antenna structure web (also referred to as a short-circuit web).
• the antenna structure web can run parallel to the feed line.
• the antenna structure web can be a substantially larger one, parallel to the feed line running length as (running perpendicular to the feed line) width, in particular by a factor of 10 or more.
• the feed line and / or the antenna structure web typically run perpendicular to a longitudinal direction or longitudinal edge of the antenna structure. Furthermore, the
• Antenna structure web can be arranged at one end and / or on a transverse edge of the antenna structure (in particular at the end or on the transverse edge which faces the second partial reference area).
• the antenna structure in particular at the end or on the transverse edge which faces the second partial reference area.
• the antenna structure web has a width of F * 0.9mm ⁇ 10%. Furthermore, the
• Antenna structure web in particular an edge of the antenna structure web facing the feed line
• the impedance of the antenna structure can be set in an efficient and precise manner. Furthermore, the required size of the antenna structure can be reduced. Furthermore, electrostatic discharges can be reliably kept away from the transmitting / receiving electronics of the described antenna via the (short-circuit) web to the reference area, in particular to the second partial reference area.
• the reference area can be subdivided into a first partial reference area and into a second partial reference area by the feed recess and the web recess.
• the subdivision can be such that the first sub-reference area and the second sub-reference area are not directly electrically conductively coupled to one another on the outer layer (but possibly only indirectly via a
• the second partial reference area can have an L-shape.
• the first partial reference area can have an L-shape (possibly with respect to the feed line) arranged in a mirror-inverted manner to the second partial reference area, on which the L-shape is additionally parallel to a leg of the L-shape running perpendicular to the feed line
• Reference area web is arranged.
• the first partial reference area and the second partial reference area can thus (apart from the additional reference area web) have the same shape and / or the same dimensions, and possibly mirror images in Be arranged with respect to the feed line.
• an antenna can be provided which can be used in a particularly flexible manner in different constellations.
• a leg of the first partial reference area and / or the second partial reference area extending parallel to the feed line each has a length (running parallel to the feed line) of F * 7.4 mm ⁇ 10% (starting from a the antenna structure facing longitudinal edge of the
• the longitudinal edge of the antenna structure facing the reference area is at a distance of F * 1.3 mm ⁇ 10% from the longitudinal edge of the leg of the first partial reference area and / or the second partial reference area that runs perpendicular to the feed line.
• the circuit board antenna can comprise an electrically conductive further outer layer of the circuit board. Furthermore, the circuit board antenna can comprise an electrically conductive further reference area on the further outer layer. The reference area (the (first) outer layer) can cover one or more
• Vias can be electrically conductively connected to the further reference area (the further outer layer).
• the reference area can have a U-shape without the reference area web and without the feed recess (which is composed of the two L-shaped sub-reference areas mentioned above).
• the antenna structure can be enclosed on three sides by the U-shape of the reference area.
• the reference area web can enclose at least part of the fourth side of the antenna structure (and run parallel to it).
• the further reference area can also have a U-shape.
• the U-shape of the further reference area and the U-shape of the reference area can be dimensioned identically and / or arranged directly one above the other.
• An antenna that can be replaced in a particularly flexible manner can thus be provided.
• the (first) outer layer and / or the further (second) outer layer are typically each formed by an electrically conductive layer, in particular by a copper layer, of a circuit board.
• the outer layer and the further outer layer are typically isolated from one another by at least one dielectric layer.
• a printed circuit board can have at least one electrically conductive intermediate layer (e.g. a copper layer) which is arranged between the outer layer and the further outer layer.
• the intermediate layer preferably has in a region of the antenna structure and / or the reference region web (as well as the
• the intermediate layer in a region of the reference region can be connected in an electrically conductive manner to the reference region via one or more vias. So can also with a circuit board with one or more
• a household appliance in particular a household appliance, which comprises a communication unit for wireless communication (in particular via WLAN), the communication unit having the printed circuit board antenna described in this document.
• FIG. 1a shows the upper or (first) outer layer of a printed circuit board with an antenna
• FIG. 1 b shows the lower layer or the second or further outer layer of a circuit board
• FIGS. 1c and 1d are cross sections through circuit boards, each with an antenna
• FIGS. 2a and 2b show exemplary dimensions of an antenna
• FIG. 3 exemplary frequency curves of antennas of different dimensions.
• the present document is concerned with the provision of a (dual-band) antenna which can be integrated in an efficient manner on differently dimensioned and / or designed circuit boards and / or in different environments.
• the (dual-band) antenna should be designed in particular for WLAN radio communication in the frequency bands at 2.4 GHz and 5 GHz.
• FIGS. 1 a and 1 b show an exemplary antenna 100 which is integrated on a circuit board 101.
• FIG. 1 a shows the (electrically conductive) upper layer 110 of the circuit board 101
• FIG. 1 b shows the (electrically conductive) lower layer 120 of the circuit board.
• one or more dielectric layers 130 and optionally one or more (electrically conductive) intermediate layers 150 are located between the upper layer 110 and the lower layer 120.
• the electrically conductive layers 110, 120, 150 can have a layer made of metal, in particular copper. The metal can be removed (e.g. etched away) in partial areas of the layers 110, 120, 150 in order to form different electrically conductive partial areas within a layer 110, 120, 150, the partial areas being electrically isolated from one another.
• the upper layer 110 has an electrically conductive antenna structure 113 which is insulated from an electrically conductive reference area 111, 141 via an (electrically non-conductive) free space 112.
• the reference area 111, 141 at least partially encloses the antenna structure 113.
• the reference area 111, 141 enclosing the antenna structure 113 is interrupted at a first point in order to form a free space or recess 117 through which an electrically conductive feed line 115 can be led to the antenna structure 113.
• the reference region 111, 141 has a second recess 142 in order to form a reference region web 143 running parallel to the antenna structure 113.
• the reference area 111, 141 is thus divided into two sub-reference areas, in particular a first sub-reference area 111 and a second sub-reference area 141.
• the reference area web 143 is connected in an electrically conductive manner to the first partial reference area 111.
• the antenna structure 113 has a rectangular shape.
• the antenna structure 113 can be used to transmit or receive signals in a specific first frequency range (approximately 5.1-5.8 GHz).
• the antenna structure 113 can form a 1/4 radiator for a specific first frequency range through the overall length 205 of the antenna structure 113.
• the free space 112 between the antenna structure 113 and the reference area bar 143 of the reference area 111, 141, and / or the reference area bar 143 itself can be used as a (slot) antenna for a further (second) frequency range (approximately 2.4-2 , 5 GHz) can be used.
• the free space 112 and in particular the reference area bar 143 can have a certain length 208 so that the free space 112 and / or the reference area bar 143 form a 1/4 radiator for a further (second) frequency range.
• the antenna structure 113 can be connected in an electrically conductive manner to the reference area 111, 141, in particular to the second partial reference area 141, via an electrically conductive antenna structure web (in particular via a short-circuit web) 116.
• the electrically conductive antenna structure web 116 can be arranged at one end of the antenna structure 113, in particular at the narrowest transverse edge of the antenna structure 113.
• the antenna structure 113 can thus form a (planar) inverted-F antenna.
• the impedance of the antenna structure 113 can be trimmed to a desired value (e.g. 50 ohms) via the distance 206 between the web 116 and the feed point or the feed line 115.
• electrostatic discharges can largely be kept away from the transmit / receive electronics of the antenna 100 via this short-circuit web 116.
• FIG. 1b shows the lower layer 120 of the printed circuit board 101.
• the lower layer 120 is at least partially constructed identically to the upper layer 110.
• the lower layer 120 in the example shown has a reference region 121 which is identical (apart from the first recess 117 and apart from the web 143) ok
• the reference area 121 has a U-shape, with a base 124 running parallel to the rectangular antenna structure 113 and two legs 123.
• the reference region 111 of the upper layer 110 can be connected in an electrically conductive manner to the reference region 121 of the lower layer 120 via one or more vias or plated-through holes 114.
• the vias or plated-through holes 114 are shown as points in FIGS. 1a and 1b. The exact position of the one or more vias or plated-through holes 114 can vary depending on the via technology.
• FIGS. 1c and 1d show exemplary cross-sections through exemplary printed circuit boards 101 with an antenna structure 113.
• a printed circuit board 101 has a dielectric and / or electrically insulating layer 130 between two electrically conductive layers 110, 120.
• the circuit board 101 has (at least) one electrically conductive intermediate layer 150 between the upper layer 110 and the lower layer 120, which is separated from the upper layer 110 and the lower layer 120 by a dielectric layer 130 is separated.
• FIG. 1d illustrates the area 141 in which the antenna structure 113 shown in FIG. 1a, including the free space 112, are arranged.
• This region 151 of an intermediate layer 150 is typically to be cut out so that the intermediate layer 150 does not have any electrically conductive material (in particular no copper) in this region 151.
• the remaining region 152 of an intermediate layer 150 can be electrically conductively connected to the reference region 111, 121 of the upper layer 110 and the lower layer 120 via the vias or plated-through holes 114.
• FIGS. 2a and 2b show different dimensions of the antenna 100 from FIGS. 1a and 1b.
• FIGS. 2a and 2b show different dimensions of the antenna 100 from FIGS. 1a and 1b.
• FIGS. 2a and 2b show different dimensions of the antenna 100 from FIGS. 1a and 1b.
• FIGS. 2a and 2b show different dimensions of the antenna 100 from FIGS. 1a and 1b.
• Antenna structure web 116 facing the free space 112, edge of a leg of the second partial reference region 141;
• this distance 212 typically corresponds to the distance 210;
• the depth 213 of the legs 123 of the reference area 121 of the lower layer 120 (starting from the edge of the base 124 of the reference area 121 facing the free space 122); this depth 213 typically corresponds to the distance 204.
• the circuit board 101 may e.g. have a strength or thickness of 1, 5mm.
• Any copper intermediate layer 150 preferably has a rectangular cutout 151 with a size of 7.7 mm ⁇ 22 mm.
• the intermediate layer 150 can be connected to the reference regions 111, 141, 121 of the outer layers 110, 120 via external vias 114.
• the above Values can fluctuate by up to ⁇ 10% (especially around the
• the values can be scaled with a common factor F if necessary.
• the circuit board antenna 100 can be arranged on a circuit board 101 with a size of 49 mm ⁇ 43 mm. In this case, several of the
• circuit board antennas 100 described, e.g. One antenna 100 each on a long edge and on a short edge of the circuit board 101.
• the individual antennas 100 can be adapted and / or optimized to the position within the circuit board 101 (for example by adapting the above values of an antenna 100 in a range of ⁇ 10%).
• a planar printed circuit board antenna structure 113 is thus described which is surrounded or respectively surrounded by the reference ground (i.e. by a reference area 111, 121, 141).
• the reference areas 111, 121, 141 can be coupled to ground in an electrically conductive manner.
• the properties of the antenna 100 are independent of the size of the reference ground of a circuit board 101.
• the antenna 100 can be installed in an efficient manner in circuit cards 101 of different sizes and / or in different environments without the
• Antenna structure 113 and / or a “matching circuit” must be changed. As a result, a module approval for the antenna 100 described can be used for various overall devices regardless of the specific installation situation.
• the antenna 100 described can be an expanded form of a planar inverted F antenna (PIFA, for English: Planar Inverted F-Shaped Antenna) (formed by the antenna structure 113).
• PIFA planar inverted F antenna
• the antenna 110 has a
• the additional resonator can thereby via the gap (i.e. the free space 112) between the rectangle 118 of the inverted-F antenna 113 and the
• Reference area web 143 are capacitively excited by the inverted-F antenna 113.
• This capacitive coupling is preferably designed to be relatively weak, whereby the
• Resonances of the inverted-F antenna 113 and of the reference area bar 153 become relatively broadband.
• the radiation behavior of the antenna 100 is relatively little if the resonance frequencies shift (e.g. due to plastic (e.g. the housing of a device) in the vicinity of the antenna 100, or due to manufacturing tolerances).
• the quality of the antenna 100 is therefore relatively insensitive to manufacturing tolerances.
• the antenna 100 can be operated in different installation situations without having to shift the resonances by adapting the structure of the antenna 100 or by using a “matching circuit”. The antenna 100 can thus be approved independently of the
• Installation situation can be used for various overall devices.
• FIG. 3 shows exemplary frequency responses 301, 302, 303 of different antennas.
• a resonance frequency in the frequency range 2.4-2.5 GHz can be seen for all antennas.
• Two of the antennas (frequency responses 301, 302) also have a resonance frequency in the frequency range 5.1-5.8 GHz. It can be seen that the antennas with the two resonance frequencies in the respective Frequency ranges are broader than the antenna, which has only one resonance frequency. This enables flexible use of the dual-band antennas.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Details Of Aerials (AREA)

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• 2019
  • 2019-04-17 DE DE102019205556.7A patent/DE102019205556A1/de active Pending
• 2020
  • 2020-04-02 WO PCT/EP2020/059388 patent/WO2020212153A1/de unknown
  • 2020-04-02 US US17/441,548 patent/US11881636B2/en active Active
  • 2020-04-02 CN CN202080029279.XA patent/CN113711437B/zh active Active
  • 2020-04-02 EP EP20743963.9A patent/EP3956944A1/de active Pending

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