PATENT DOCUMENT

Publication Number: US-9997828-B2
Application Number: US-201615071795-A
Country: US
Kind Code: B2

Title: Electronic device with shared antenna structures and balun

Abstract:
An electronic device may be provided with shared antenna structures that can be used to form both a near-field-communications antenna such as a loop antenna and a non-near-field communications antenna such as an inverted-F antenna. The antenna structures may include conductive structures such as metal traces on printed circuits or other dielectric substrates, internal metal housing structures, or other conductive electronic device housing structures. A main resonating element arm may be separated from an antenna ground by an opening. A non-near-field communications antenna return path and antenna feed path may span the opening. A balun may have first and second electromagnetically coupled inductors. The second inductor may have terminals coupled across differential signal terminals in a near-field communications transceiver. The first inductor may form part of the near-field communications loop antenna.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 an antenna having a resonating element arm, an antenna ground, an antenna feed path, and an antenna return path coupled between the resonating element arm and the antenna ground; 
 non-near-field communications transceiver circuitry coupled to the antenna that handles non-near-field communications using the antenna; 
 near-field communications transceiver circuitry coupled to the antenna, wherein the near-field communications circuitry handles near-field communications using a loop antenna that includes at least part of the return path of the antenna; and 
 an inductor coupled between the near-field communications transceiver circuitry and the resonating element arm. 
 
     
     
       2. The electronic device defined in  claim 1 , further comprising:
 a balun that couples the near-field communications circuitry to the antenna. 
 
     
     
       3. The electronic device defined in  claim 1 , wherein the antenna comprises an inverted-F antenna. 
     
     
       4. The electronic device defined in  claim 1 , wherein the non-near-field communications circuitry handles non-near-field communications in a cellular telephone communications band using the antenna. 
     
     
       5. The electronic device defined in  claim 1 , wherein the non-near-field communications circuitry handles communications at frequencies greater than 700 MHz. 
     
     
       6. The electronic device defined in  claim 1 , wherein the loop antenna further includes a portion of the resonating element arm. 
     
     
       7. The electronic device defined in  claim 1 , wherein the loop antenna further includes a portion of the antenna feed path. 
     
     
       8. An electronic device, comprising:
 an inverted-F antenna having an antenna resonating element, an antenna ground, an antenna feed path, and an antenna return path coupled between the resonating element arm and the antenna ground; 
 wireless communications circuitry coupled to the inverted-F antenna that transmits and receives wireless signals in a frequency band using the inverted-F antenna; 
 wireless circuitry that receives wireless signals at a frequency that is below the frequency band using a loop antenna that includes at least part of the inverted-F antenna; and 
 an inductor coupled between the antenna resonating element and the wireless circuitry. 
 
     
     
       9. The electronic device defined in  claim 8 , wherein the loop antenna includes at least part of the antenna return path of the inverted-F antenna. 
     
     
       10. The electronic device defined in  claim 8 , wherein the loop antenna includes at least part of the antenna resonating element of the inverted-F antenna. 
     
     
       11. The electronic device defined in  claim 8 , wherein the loop antenna includes at least part of the antenna feed path of the inverted-F antenna. 
     
     
       12. The electronic device defined in  claim 8 , wherein the frequency band includes frequencies that are greater than or equal to 700 MHz. 
     
     
       13. The electronic device defined in  claim 12 , wherein the frequency is less than 700 MHz. 
     
     
       14. The electronic device defined in  claim 8 , wherein the wireless communications circuitry comprises cellular telephone transceiver circuitry that transmits and receives wireless signals in a cellular telephone communications band. 
     
     
       15. An electronic device, comprising:
 first wireless transceiver circuitry that transmits and receives first wireless signals in a frequency band; 
 second wireless transceiver circuitry that receives second wireless signals at a frequency that is lower than the frequency band; 
 an inverted-F antenna that transmits and receives the first wireless signals for the first wireless transceiver circuitry; and 
 a loop antenna that includes a portion of the inverted-F antenna and that receives the second wireless signals for the second wireless transceiver circuitry, wherein the loop antenna comprises an inductor coupled between the portion of the inverted-F antenna and the second wireless transceiver circuitry. 
 
     
     
       16. The electronic device defined in  claim 15 , further comprising:
 power management circuitry coupled to the second wireless circuitry. 
 
     
     
       17. The electronic device defined in  claim 15 , wherein the first wireless circuitry comprises cellular telephone transceiver circuitry that transmits and receives the first wireless signals in a cellular telephone communications band that includes frequencies greater than 700 MHz. 
     
     
       18. The electronic device defined in  claim 15 , wherein the first wireless circuitry comprises wireless local area network transceiver circuitry that transmits and receives the first wireless signals in a wireless local area network communications band that includes frequencies greater than 700 MHz. 
     
     
       19. The electronic device defined in  claim 15 , wherein the loop antenna includes at least a portion of a return path of the inverted-F antenna. 
     
     
       20. The electronic device defined in  claim 1 , wherein the loop antenna includes an additional path having an additional inductor thereon and the additional path couples the resonating element arm to the antenna ground via the additional inductor.

Description:
This application is a continuation of U.S. patent application Ser. No. 14/195,130, filed Mar. 3, 2014. This application claims the benefit of and claims priority to U.S. patent application Ser. No. 14/195,130, filed Mar. 3, 2014, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates to electronic devices, and more particularly, to antennas for electronic devices with wireless communications circuitry. 
     Electronic devices such as portable computers and cellular telephones are often provided with wireless communications capabilities. For example, electronic devices may use long-range wireless communications circuitry such as cellular telephone circuitry to communicate using cellular telephone bands. Electronic devices may use short-range wireless communications circuitry such as wireless local area network communications circuitry to handle communications with nearby equipment. Electronic devices may also be provided with satellite navigation system receivers and other wireless circuitry such as near-field communications circuitry. Near-field communications schemes involve electromagnetically coupled communications over short distances, typically 20 cm or less. 
     To satisfy consumer demand for small form factor wireless devices, manufacturers are continually striving to implement wireless communications circuitry such as antenna components using compact structures. At the same time, there is a desire for wireless devices to cover a growing number of communications bands. For example, it may be desirable for a wireless device to cover a near-field communications band while simultaneously covering additional non-near-field (far field) bands such cellular telephone bands, wireless local area network bands, and satellite navigation system bands. 
     Because antennas have the potential to interfere with each other and with components in a wireless device, care must be taken when incorporating antennas into an electronic device. Moreover, care must be taken to ensure that the antennas and wireless circuitry in a device are able to exhibit satisfactory performance over a range of operating frequencies. 
     It would therefore be desirable to be able to provide improved wireless communications circuitry for wireless electronic devices. 
     SUMMARY 
     An electronic device may be provided with antenna structures that form both a near-field-communications antenna such as a loop antenna and a non-near-field communications antenna such as an inverted-F antenna. A non-near-field communications circuit such as a cellular telephone transceiver, wireless local area network transceiver, or other non-near-field communications transceiver may wirelessly communicate using the non-near-field communications antenna. A near-field communications transceiver may wirelessly communicate using the near-field communications antenna. By sharing portions of the antenna structures between the non-near-field communications antenna and the near-field communications antenna, space in the electronic device may be conserved. 
     The antenna structures may include conductive structures such as metal traces on printed circuits or other dielectric substrates, internal metal housing structures, or conductive peripheral electronic device housing structures. A main resonating element arm may be separated from an antenna ground by an opening. A non-near-field communications antenna return path and antenna feed path may span the opening. The main resonating element arm, the return path, the feed path, and the antenna ground may form a non-near-field communications antenna such as an inverted-F antenna. The non-near-field communications transceiver may be coupled to the antenna feed path of the inverted-F antenna. 
     A balun may have first and second electromagnetically coupled inductors. The second inductor may have terminals coupled across differential signal terminals in a near-field communications transceiver. The first inductor may form part of the near-field communications loop antenna, so that the balun couples the non-near-field communications transceiver to the loop antenna. The loop antenna may include portions of the antenna ground, portions of the antenna resonating element arm in the non-near-field communications antenna, portions of the antenna return path in the non-near-field communications antenna, portions of the antenna feed in the non-near-field communications antenna, portions of an antenna tuning path in the non-near-field communications antenna, or other signal paths in the antenna structures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment. 
         FIG. 3  is a diagram of a system in which antenna structures in an electronic device are being used to wirelessly communicate with external electrical equipment using near-field communications and non-near-field communications in accordance with an embodiment. 
         FIG. 4  is a diagram of an illustrative electronic device with antenna structures in accordance with an embodiment. 
         FIG. 5  is a diagram of an electronic device having antenna structures that can be used to handle both non-near-field communications and near-field communications and that include a balun coupled to an antenna return path with a signal path that runs parallel to a peripheral conductive housing member in accordance with an embodiment. 
         FIG. 6  is a diagram of an electronic device having antenna structures that can be used to handle both non-near-field communications and near-field communications and that include a balun coupled to a conductive peripheral electronic device housing structure in the antenna structures in accordance with an embodiment. 
         FIG. 7  is a diagram of an electronic device having antenna structures that can be used to handle both non-near-field communications and near-field communications and that include a balun coupled to an antenna return path in accordance with an embodiment. 
         FIG. 8  is a diagram of an electronic device having antenna structures that can be used to handle both non-near-field communications and near-field communications and that include a balun coupled to an antenna feed path in accordance with an embodiment. 
         FIG. 9  is a diagram of an electronic device having antenna structures that can be used to handle both non-near-field communications and near-field communications and that include a balun coupled to an antenna tuning path in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with wireless circuitry. The wireless circuitry may include near-field communications circuitry. For example, a near-field communications transmitter-receiver (“transceiver”) may use a near-field communications antenna to transmit and receive near-field electromagnetic signals at a frequency such as 13.56 MHz. Near-field communications schemes involve near-field electromagnetic coupling between near-field antennas that are separated by a relatively small distance (e.g., 20 cm or less). The near-field communications antennas may be loop antennas. The wireless circuitry may also include cellular network transceiver circuitry, wireless local area network transceiver circuitry, satellite navigation system circuitry, or other non-near-field communications circuitry. The non-near-field communications circuitry can use an antenna to handle radio-frequency signals at frequencies of 700 MHz to 2700 MHz, 5 GHz, or other suitable frequencies. 
     To conserve space within an electronic device, a near-field communications antenna and a non-near-field communications antenna can be formed from shared antenna structures. For example, conductive electronic device housing structures, metal traces on printed circuits and other substrates, and other conductive structures in an electronic device may be configured to serve both as a non-near-field antenna and as a near-field antenna. 
       FIG. 1  is a perspective view of an illustrative electronic device of the type that may be provided with wireless circuitry having antenna structures that are shared between near-field communications circuitry and non-near-field communications circuitry. The wireless communications circuitry may be used to support wireless communications in multiple wireless communications bands. The wireless communications circuitry may include antenna structures that include loop antennas, inverted-F antennas, strip antennas, planar inverted-F antennas, slot antennas, hybrid antennas that include antenna structures of more than one type, or other suitable antennas. 
     Antenna structures may, if desired, be formed from conductive electronic device structures. The conductive electronic device structures may include conductive housing structures. The housing structures may include a peripheral conductive member or other conductive peripheral electronic device housing structures running around the periphery of an electronic device. The peripheral conductive housing structures may serve as a bezel for a planar structure such as a display and/or may form vertical sidewalls for the device. 
     The antenna structures may be configured to handle both near-field communications (e.g., communications in a near-field communications band such as a 13.56 MHz band or other near-field communications band) and non-near-field communications (sometimes referred to as far field communications) such as cellular telephone communications, wireless local area network communications, and satellite navigation system communications. Near-field communications typically involve communication distances of less than about 20 cm and involve magnetic (electromagnetic) near-field coupling between near-field antennas such as loop antennas. Far field communications typically involved communication distances of multiple meters or miles. 
     Electronic device  10  may be a portable electronic device or other suitable electronic device. For example, electronic device  10  may be a laptop computer, a tablet computer, a somewhat smaller device such as a wrist-watch device, pendant device, headphone device, earpiece device, or other wearable or miniature device, a cellular telephone, or a media player. Device  10  may also be a television, a set-top box, a desktop computer, a computer monitor into which a computer has been integrated, a television, a computer monitor, or other suitable electronic equipment. 
     Device  10  may include a housing such as housing  12 . Housing  12 , which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of these materials. In some situations, parts of housing  12  may be formed from dielectric or other low-conductivity material. In other situations, housing  12  or at least some of the structures that make up housing  12  may be formed from metal elements. 
     Device  10  may, if desired, have a display such as display  14 . Display  14  may, for example, be a touch screen that incorporates capacitive touch electrodes. Display  14  may include image pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, or other suitable image pixel structures. A display cover layer such as a cover glass layer or a layer of clear plastic may cover the surface of display  14 . Buttons such as button  19  may pass through openings in the display cover layer or other outer layer in display  14 . The cover glass may also have other openings such as an opening for speaker port  26 . 
     Housing  12  may include peripheral conductive housing structures  16  such as a metal member or other conductive member. Peripheral conductive housing structures  16  may run around the periphery of device  10  and display  14 . In configurations in which device  10  and display  14  have rectangular shapes, peripheral conductive housing structures  16  may have a rectangular ring shape (as an example). Peripheral conductive housing structures  16  or part of peripheral conductive housing structures  16  may serve as a bezel for display  14  (e.g., a cosmetic trim that surrounds all four sides of display  14  and/or helps hold display  14  to device  10 ). Peripheral conductive housing structures  16  may also, if desired, form sidewall structures for device  10  (e.g., by forming a band with vertical sidewalls, by forming a band with rounded sidewalls, etc.). If desired, peripheral conductive housing structures  16  such as housing sidewalls may be formed as integral portions of a metal rear housing wall for device  10  (i.e., the rear surface and edges of housing  12  may be formed from a conductive material such as metal). 
     Peripheral conductive housing structures  16  may include a peripheral conductive member such as a peripheral metal member, a peripheral metal housing band, or other peripheral conductive housing member, may include a metal display bezel, may include metal housing sidewalls, or may include other peripheral conductive housing structures. Peripheral conductive housing structures  16  (e.g., a metal member) may be formed from a metal such as stainless steel, aluminum, or other suitable materials. One, two, three, or more than three separate structures may be used in forming a peripheral conductive housing member or metal sidewalls may be separated into one, two, three, or more than three sidewall segments. 
     It is not necessary for peripheral conductive housing structures  16  to have a uniform cross-section. For example, the top (front face) portion of peripheral conductive housing structures  16  may, if desired, have an inwardly protruding lip that helps hold display  14  in place. If desired, the bottom portion of peripheral conductive housing structures  16  may also have an enlarged lip (e.g., in the plane of the rear surface of device  10 ). In the example of  FIG. 1 , structures  16  have substantially straight vertical sidewalls. This is merely illustrative. Sidewalls in housing  12  may be curved or may have any other suitable shape. In some configurations (e.g., when structures  16  serve as a bezel for display  14 ), structures  16  may run around the lip of housing  12  (i.e., structures  16  may cover only the edge of housing  12  that surrounds display  14  and not the rear edge of housing  12  of the sidewalls of housing  12 ). 
     Display  14  may include conductive structures such as an array of capacitive touch sensor electrodes, conductive lines for addressing display pixel elements, driver circuits, etc. Housing  12  may include internal structures such as metal frame members, a planar sheet metal housing structure (sometimes referred to as a midplate) that spans the walls of housing  12  (i.e., a substantially rectangular member that is welded or otherwise connected between opposing sides of structures  16 ), printed circuit boards, and other internal conductive structures. These conductive structures may be located in the center of housing  12  under display  14  (as an example). 
     In regions  22  and  20 , openings (gaps) may be formed within the conductive structures of device  10  (e.g., between peripheral conductive housing structures  16  and opposing conductive structures that may form an antenna ground such as conductive housing structures, a conductive ground plane associated with a printed circuit board, and conductive electrical components in device  10 ). These openings may be filled with air, plastic, and other dielectrics. Conductive housing structures and other conductive structures in device  10  may serve as a ground plane for antennas in device  10 . The openings in regions  20  and  22  may serve as slots in open or closed slot antennas, may serve as a central dielectric region that is surrounded by a conductive path of materials in a loop antenna, may serve as a space that separates an antenna resonating element such as a strip antenna resonating element or an inverted-F antenna resonating element arm from the ground plane, or may otherwise serve as part of antenna structures formed in regions  20  and  22 . 
     In general, device  10  may include any suitable number of antennas (e.g., one or more, two or more, three or more, four or more, etc.). The antennas in device  10  may be located at opposing first and second ends of an elongated device housing, along one or more edges of a device housing, in the center of a device housing, in other suitable locations, or in one or more of such locations. The arrangement of  FIG. 1  is merely illustrative. 
     Portions of peripheral conductive housing structures  16  may be provided with gap structures. For example, peripheral conductive housing structures  16  may be provided with one or more gaps such as gaps  18 , as shown in  FIG. 1 . The gaps may be filled with dielectric such as polymer, ceramic, glass, air, other dielectric materials, or combinations of these materials. Gaps  18  may divide peripheral conductive housing structures  16  into one or more peripheral conductive housing structure (member) segments. There may be, for example, two segments of a peripheral conductive housing member or other peripheral conductive housing structures  16  (e.g., in an arrangement with two gaps), three segments (e.g., in an arrangement with three gaps), four segments (e.g., in an arrangement with four gaps, etc.). The segments of the peripheral conductive housing member or other peripheral conductive housing structures that are formed in this way may form parts of antennas in device  10 . 
     If desired, device  10  may have upper and lower antennas (as an example). An upper antenna may, for example, be formed at the upper end of device  10  in region  22 . A lower antenna may, for example, be formed at the lower end of device  10  in region  20 . The antennas may be used separately to cover identical communications bands, overlapping communications bands, or separate communications bands. The antennas may be used to implement an antenna diversity scheme or a multiple-input-multiple-output (MIMO) antenna scheme. 
     Antennas in device  10  may be used to support any communications bands of interest. For example, device  10  may include antenna structures for supporting non-near-field-communications such as local area network communications, voice and data cellular telephone communications, global positioning system (GPS) communications or other satellite navigation system communications, Bluetooth® communications, etc. Device  10  may use at least part of the same antenna structures for supporting near-field communications (e.g., communications at 13.56 MHz). 
     A schematic diagram of an illustrative configuration that may be used for electronic device  10  is shown in  FIG. 2 . As shown in  FIG. 2 , electronic device  10  may include control circuitry such as storage and processing circuitry  28 . Storage and processing circuitry  28  may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in storage and processing circuitry  28  may be used to control the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio codec chips, application specific integrated circuits, etc. 
     Storage and processing circuitry  28  may be used to run software on device  10 , such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, storage and processing circuitry  28  may be used in implementing communications protocols. Communications protocols that may be implemented using storage and processing circuitry  28  include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol, cellular telephone protocols, near-field communications protocols, etc. 
     Circuitry  28  may be configured to implement control algorithms that control the use of antennas in device  10 . For example, circuitry  28  may perform signal quality monitoring operations, sensor monitoring operations, and other data gathering operations and may, in response to the gathered data and information on which communications hands are to be used in device  10 , control which antenna structures within device  10  are being used to receive and process data and/or may adjust one or more switches, tunable elements, or other adjustable circuits in device  10  to adjust antenna performance. As an example, circuitry  28  may control which of two or more antennas is being used to receive incoming radio-frequency signals, may control which of two or more antennas is being used to transmit radio-frequency signals, may control the process of routing incoming data streams over two or more antennas in device  10  in parallel, may tune an antenna to cover a desired communications band, may perform time-division multiplexing operations to share antenna structures between near-field and non-near-field communications circuitry, etc. In performing these control operations, circuitry  28  may open and close switches, may turn on and off receivers and transmitters, may adjust impedance matching circuits, may configure switches in front-end-module (FEM) radio-frequency circuits that are interposed between radio-frequency transceiver circuitry and antenna structures (e.g., filtering and switching circuits used for impedance matching and signal routing), may adjust switches, tunable circuits, and other adjustable circuit elements that are formed as part of an antenna or that are coupled to an antenna or a signal path associated with an antenna, and may otherwise control and adjust the components of device  10 . 
     Input-output circuitry  30  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output circuitry  30  may include input-output devices  32 . Input-output devices  32  may include touch screens, buttons, joysticks, click wheels, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors, light-emitting diodes and other status indicators, data ports, etc. A user can control the operation of device  10  by supplying commands through input-output devices  32  and may receive status information and other output from device  10  using the output resources of input-output devices  32 . 
     Wireless communications circuitry  34  may include radio-frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Wireless communications circuitry  34  may include satellite navigation system receiver circuitry such as Global Positioning System (GPS) receiver circuitry  35  (e.g., for receiving satellite positioning signals at 1575 MHz) or satellite navigation system receiver circuitry associated with other satellite navigation systems. 
     Wireless local area network transceiver circuitry  36  in wireless communications circuitry  34  may handle 2.4 GHz and 5 GHz bands for WiFi® (IEEE 802.11) communications and may handle the 2.4 GHz Bluetooth® communications band. 
     Circuitry  34  may use cellular telephone transceiver circuitry  38  for handling wireless communications in cellular telephone bands such as bands in frequency ranges of about 700 MHz to about 2700 MHz or bands at higher or lower frequencies. 
     Wireless communications circuitry  34  may include near-field communications circuitry  42 . Near-field communications circuitry  42  may handle near-field communications at frequencies such as the near-field communications frequency of 13.56 MHz or other near-field communications frequencies of interest. 
     Circuitry  44  such as satellite navigation system receiver circuitry  35 , wireless local area network transceiver circuitry  36 , and cellular telephone transceiver circuitry  38  that does not involve near-field communications may sometimes be referred to as non-near-field communications circuitry or far field communications circuitry. 
     Antenna structures  40  may be shared by non-near-field communications circuitry  44  and near-field communications circuitry  42 . 
     If desired, communications circuitry  34  may include circuitry for other short-range and long-range wireless links. For example, wireless communications circuitry  34  may include wireless circuitry for receiving radio and television signals, paging circuits, etc. In near-field communications, wireless signals are typically conveyed over distances of less than 20 cm. In WiFi® and Bluetooth® links and other short-range wireless links, wireless signals are typically used to convey data over tens or hundreds of feet. In cellular telephone links and other long-range links, wireless signals are typically used to convey data over thousands of feet or miles. 
     Wireless communications circuitry  34  may include antenna structures  40 . Antenna structures  40  may include one or more antennas. Antennas structures  40  may be formed using any suitable antenna types. For example, antenna structures  40  may include antennas with resonating elements that are formed from loop antenna structures, patch antenna structures, inverted-F antenna structures, closed and open slot antenna structures, planar inverted-F antenna structures, helical antenna structures, strip antennas, monopoles, dipoles, hybrids of these designs, etc. Different types of antennas may be used for different bands and combinations of bands. For example, one type of antenna may be used in forming a local wireless link antenna and another type of antenna may be used in forming a remote wireless link. 
     To accommodate near-field communications within the potentially tight confines of device housing  12 , antenna structures  40  may be shared between non-near-field communications circuitry  44  and near-field communications circuitry  42 . When, for example, it is desired to transmit and receive cellular telephone signals or other non-near-field communications, antenna structures  40  may be used by cellular telephone transceiver circuitry  38  or other non-near-field transceiver circuitry  44 . When it is desired to transmit and receive near-field communications signals, antenna structures  40  may be used by near-field communications circuitry  42 . 
       FIG. 3  is a schematic diagram showing how antenna structures  40  may be shared by near-field communications circuitry  42  and non-near-field communications circuitry  44 . As shown in  FIG. 3 , electronic device  10  includes control circuitry  28  and input-output devices  32 . Control circuitry  28  may use input-output devices  32  to provide output to a user and to receive input. Control circuitry  28  may use wireless transceiver circuitry  50  and antenna structures  40  to communicate with external equipment over one or more wireless communications bands including bands for non-near-field communications and near-field communications. 
     Near-field communications circuitry  42  and non-near-field communications circuitry  44  may be coupled to antenna structures  40 . Near-field communications circuitry  42  (e.g., a near-field communications transceiver) uses antenna structures  40  to communicate with external near-field communications equipment  58  over near-field communications link  64 . Non-near-field communications circuitry such as radio-frequency transceiver circuitry  44  uses antenna structures  40  to communicate with a cellular telephone network, a wireless local area network, or other far field (non-near-field) wireless network equipment  54  over non-near-field communications wireless link  56 . 
     External equipment such as external equipment  58  may communicate with near-field communications circuitry  42  via magnetic induction. Equipment  58  may include a loop antenna such as loop antenna  62  that is controlled by control circuitry  60 . Loop antenna  62  and a loop antenna formed from antenna structures  40  may be electromagnetically coupled to support near-field wireless communications when loop antenna  62  and the loop antenna in structures  40  are within an appropriately close distance of each other such as 20 cm or less, as indicated by near-field communications signals  64  of  FIG. 3 . 
     Device  10  may use near-field communications circuitry  42  and antenna structures  40  (e.g., the near-field communications loop antenna portion of antenna structures  40 ) to communicate with external near-field communications equipment  58  using passive or active communications. In passive communications, device  10  may use near-field communications circuitry  42  and antenna structures  40  to modulate electromagnetic signals  64  from equipment  58 . In active communications, near-field communications circuitry  42  and antenna structures  40  may transmit radio-frequency electromagnetic signals  64  to external equipment  58 . 
     To provide antenna structures  40  with the ability to cover communications frequencies of interest, antenna structures  40  may be provided with circuitry such as filter circuitry (e.g., one or more passive filters and/or one or more tunable filter circuits). Discrete components such as capacitors, inductors, and resistors may be incorporated into the filter circuitry. Capacitive structures, inductive structures, and resistive structures may also be formed from patterned metal structures (e.g., part of an antenna). 
     If desired, antenna structures  40  may be provided with adjustable circuits such as tunable circuitry  52 . Tunable circuitry  52  may be controlled by control signals from control circuitry  28 . For example, control circuitry  28  may supply control signals to tunable circuitry  52  via control path  66  during operation of device  10  whenever it is desired to tune antenna structures  40  to cover a desired communications band (e.g., a desired non-near-field communications band). Paths  68  may be used to convey data between control circuitry  28  and transceiver circuitry  50 . 
     Passive filter circuitry in antenna structures  40  may help antenna structures  40  exhibit antenna resonances in communications bands of interest (e.g., passive filter circuitry in antenna structures  40  may short together different portions of antenna structures  40  and/or may form open circuits or pathways of other impedances between different portions of antenna structures  40  to ensure that desired antenna resonances are produced). 
     Transceiver circuitry  50  may be coupled to antenna structures  40  by signal paths such as signal paths  70  and  72 . Signal paths  70  and  72  may include transmission lines, portions of conductive housing structures, ground plane structures, traces on printed circuits, or other conductive paths. 
     Impedance matching circuitry formed from components such as inductors, resistors, and capacitors may be used in matching the impedance of antenna structures  40  to the impedance of transmission line structures coupled to antenna structures  40 . Filter circuitry may also be provided in the transmission line structures and/or antenna structures  40 . Matching network components may be provided as discrete components (e.g., surface mount technology components) or may be formed from housing structures, printed circuit board structures, traces on plastic supports, etc. Components such as these may also be used in forming passive filter circuitry in antenna structures  40  and tunable circuitry  52  in antenna structures  40 . 
     A transmission line may be coupled between transceiver  44  and antenna feed structures associated with antenna structures  40 . As an example, antenna structures  40  may form a non-near-field communications antenna such as an inverted-F antenna having an antenna feed with a positive antenna feed terminal and a ground antenna feed terminal. A positive transmission line conductor may be coupled to the positive antenna feed terminal and a ground transmission line conductor may be coupled to the ground antenna feed terminal. Other types of antenna feed arrangements may be used to couple non-near-field communications transceiver  44  to antenna structures  40  if desired. 
     Near-field communications circuitry  42  may be coupled to antenna structures  40  using a balun. Near-field communications circuitry  42  may have a differential output. The balun may convert differential output (signals referenced to each other) from circuitry  42  to single-ended signals (signals referenced to ground) for feeding the near-field communications antenna formed from antenna structures  40 . 
     Tunable circuitry  52  may be formed from one or more tunable circuits such as circuits based on capacitors, resistors, inductors, and switches. Tunable circuitry  52  and filter circuitry in antenna structures  40  may be implemented using discrete components mounted to a printed circuit such as a rigid printed circuit board (e.g., a printed circuit board formed from glass-filled epoxy) or a flexible printed circuit formed from a sheet of polyimide or a layer of other flexible polymer, a plastic carrier, a glass carrier, a ceramic carrier, or other dielectric substrate. During operation of device  10 , control circuitry  28  may issue commands on path  66  to adjust switches, variable components, and other adjustable circuitry in tunable circuitry  52 , thereby tuning antenna structures  40 . If desired, tunable circuitry  52  may include one or more inductors. A switch circuit may be used to selectively switch a desired number of the inductors into use. By varying the inductance of tunable circuitry  52  in this way, antenna structures  40  can be tuned to cover desired communications bands. Tunable circuitry  52  may also include one or more capacitors that are selectively switched into use with a switching circuit to tune antenna structures  40 . Capacitance adjustments and inductance adjustments may be made using a tunable circuit with adjustable capacitors and inductors and/or separately adjustable capacitor circuits and inductor circuits may be used in tuning antenna structures  40 . 
     Antenna structures  40  may be used in forming a non-near-field antenna based on inverted-F antenna design or antenna structures with other designs. An illustrative configuration for electronic device  10  that incorporates inverted-F antenna structures  40  is shown in  FIG. 4 . As shown in  FIG. 4 , antenna structures  40  may include inverted-F antenna resonating element  76  and antenna ground  88 . Antenna ground  88  may be formed from ground traces on a flexible printed circuit, ground traces on a rigid printed circuit board, metal traces on other dielectric carriers, portions of an electronic device housing such as a metal midplate structure or internal frame structures, conductive structures such as metal portions of electrical components in device  10 , or other conductive structures. Inverted-F antenna resonating element  76  may be formed from a segment of peripheral conductive housing structures  16  (e.g., a segment of a metal band or other metal member that surrounds display  14 , etc.), other metal housing structures, metal portions of electronic components in device  10 , metal traces on printed circuit substrates, plastic carriers, or other dielectric substrates, or other conductive structures. 
     Antenna resonating element  76  may include main antenna resonating element arm  78  (e.g., a segment of peripheral conductive housing structures  16  between respective peripheral conductive housing structure gaps such as gaps  18 - 1  and  18 - 2 ). Main antenna resonating element arm  78  may have one or more branches. For example, arm  78  may have a low band arm LB for producing a low communications band resonance and a high band arm HB for producing a high communications band resonance. Tip portion  94  of high band branch HB may be separated by gap  18 - 2  from ground plane  88  and may have an associated capacitance C 2 . Tip portion  92  of low band branch LB may be separated by gap  18 - 1  from ground plane  88  and may have associated capacitance C 1 . The size and shapes of the metal structures adjoining gaps  18 - 1  and  18 - 2  may be configured to adjust the values of C 1  and C 2  and thereby adjust antenna performance. If desired, optional inductors may span gaps  18 - 1  and  18 - 2  (e.g., to adjust antenna frequency response and/or provide a current path for forming a near-field communications loop antenna). 
     Arm  78  may be separated from ground plane  88  by a dielectric-filled opening such as gap  90 . Gap  90  may contain plastic, glass, ceramic, air, or other dielectric materials. Non-near-field communications antenna return path  80  in the non-near-field communications antenna of antenna structures  40  may bridge gap  90 . Non-near-field communications antenna feed path  82  may bridge gap  90  in parallel with return path  80 . Antenna feed terminals such as positive antenna feed terminal  84  and ground antenna feed terminal  86  may form a non-near-field communications antenna feed within antenna feed path  82 . The conductive structures of antenna return path  80  and antenna feed path  82  may be formed from metal traces on printed circuits, metal traces on plastic carriers, conductive housing structures, or other conductive structures in device  10 . 
     Impedance matching circuitry, filter circuitry, and tuning circuitry  52  of  FIG. 3  may be interposed in paths that bridge gap  90  such as path  80 , feed path  82 , or one or more parallel tuning paths, may bridge gaps such as gaps  18 - 1  and  18 - 2  at the tips of main antenna resonating element arm  78  of antenna resonating element  76 , may be formed in other portions of antenna resonating element  76  and/or may be incorporated into ground structures such as antenna ground  88 . 
     To support near-field communications in device  10 , device  10  preferably includes a near-field communications antenna. Space can be conserved by using some or all of antenna structures  40  both as a cellular telephone antenna or other non-near-field-communications antenna and as a near-field communications antenna. As an example, a near-field communications antenna for device  10  (e.g., an antenna that is used by near-field communications circuitry  42  of  FIG. 2  to support communications with external equipment  58  over link  64 ) may be formed using portions of the antenna structures of  FIG. 4  such as portions of antenna resonating element  76  and antenna ground  88 . By sharing conductive antenna structures between both near-field and non-near-field antennas, duplicative conductive structures can be minimized and antenna volume can be conserved within device  10 . 
     An illustrative configuration that may be used in device  10  to allow antenna structures  40  to serve both as a near-field communications antenna and a non-near-field communications antenna is shown in  FIG. 5 . In the illustrative configuration of  FIG. 5 , antenna structures  40  include antenna resonating element  76  and antenna ground  88 . Antenna resonating element arm  78  of antenna resonating element  76  is separated from antenna ground  88  by gap  90 . Path  80  spans gap  90  in parallel with antenna feed path  82 . Positive antenna feed terminal  84  and ground antenna feed terminal  86  form an antenna feed that is coupled to non-near-field communications circuitry  44  (e.g., a non-near-field communications transceiver such as a cellular telephone transceiver, wireless local area network transceiver, etc.). Ground antenna feed terminal  86  is coupled to antenna ground  88 . Circuits such as impedance matching circuit  102  and filter  100  may, if desired, be incorporated into antenna structures  40  (e.g., in antenna feed path  82  or elsewhere in structures  40 ). When it is desired to transmit and/or receive non-near-field communications signals with antenna structures  40 , antenna resonating element arm  78 , antenna return path  80 , antenna feed path  82 , and antenna ground  88  (and, if desired, other structures) serve as a non-near-field communications antenna (i.e., an inverted-F antenna) that is used by non-near-field communications circuitry  44 . 
     Near-field communications circuitry  42  (e.g., a near-field communications transceiver operating at 13.56 MHz or other suitable near-field communications frequency) may be coupled to antenna structures  40  using balun  108 . Near-field communications circuitry  42  may have a ground terminal  120  that is coupled to antenna ground  88 . Terminals  116  and  118  of circuitry  42  form a pair of differential signal terminals. The differential signal terminals are coupled to balun  108 . 
     Balun  108  may contain coupled inductors  114  and  112 . Inductors  114  and  112  may be coupled by near-field electromagnetic coupling (i.e., inductors  114  and  112  form a transformer and are magnetically coupled). Inductor  114  may have a first terminal coupled to positive terminal  116  (+V) of near-field communications circuit  42  and may have a second terminal coupled to negative terminal  118  (−V) of near-field communications circuit  42 . Inductor  112  may have a first terminal such as terminal  110  that is coupled to antenna ground  88 . Inductor  112  may also have a second terminal such as terminal  122  that couples inductor  112  to optional matching circuit  106  and inductor  104 . Matching circuit  106  may be used for impedance matching. Inductor  104  may be used to help tune the performance of antenna structures  40  when used as a near-field communications antenna. Conductive path  98  (e.g., a path that runs parallel to arm  78  and/or that includes portions of arm  78 ) is used to couple inductor  104  to node  96  on antenna return path  80 . 
     During operation of near-field communications circuit  42 , differential signals across terminals  116  and  118  are transmitted and received by a near-field communications antenna formed from a signal path that includes inductor  112 , circuits  106  and  104 , path  98 , return path  80 , and antenna ground  88 . The signal path forms a loop supporting antenna currents. Accordingly, the near-field communications antenna of  FIG. 5  is sometimes referred to as a loop antenna. During near-field communications, the loop antenna carries loop currents, as illustrated by loop current  124 . The loop currents are associated with near-field electromagnetic signals (see, e.g., wireless signals  64  of  FIG. 3 ). Balun  108  serves as a differential-to-single-ended converter that converts differential signals appearing across differential terminals  116  and  118  to single-ended loop current signals  124  flowing through the near-field communications antenna in antenna structures  40  (i.e., the loop formed from balun inductor  112 , optional matching circuit  106  and optional filter circuit  100 , path  98 , return path  80 , and antenna ground  88 ). 
     As the example of  FIG. 5  demonstrates, portions of antenna structures  40  such as return path  80  and portions of antenna ground  88  and other structures  40  can be shared between a non-near-field communications antenna (e.g., an inverted-F antenna) and a near-field communications antenna (e.g., a loop antenna), thereby helping to minimize antenna volume for device  10 . 
     Another illustrative configuration for antenna structures  40  that allows antenna structures  40  to serve both as a non-near-field communications antenna such as an inverted-F antenna and as a near-field communications antenna such as a loop antenna is shown in  FIG. 6 . In the illustrative arrangement of  FIG. 6 , non-near-field communications circuitry  44  is coupled to antenna feed terminals  84  and  86  in antenna feed path  82  of an inverted-F antenna that is formed from antenna resonating element  76  and antenna ground  88 . This allows antenna structures  40  to serve as a non-near-field communications antenna when it is desired to transmit and receive non-near-field communications signals with circuitry  44 . Near-field communications circuitry  42  is coupled to antenna structures  40  using balun  108 . Balun  108  includes inductors  114  and  112 . Inductor  114  is connected to a pair of differential signal terminals in circuit  42 . Terminal  110  of inductor  112  is coupled to antenna ground  88 . Inductor  112  also has an opposing terminal coupled to node  128 . Capacitor  136  or other circuitry for tuning the response of antenna structures  40  may be coupled between node  128  and terminal  130 . Terminal  130  may be connected to antenna ground  88 . Inductor  132  or other circuitry for tuning the response of antenna structures  40  may be coupled between node  128  and terminal  134  on antenna resonating element arm  78 . Antenna resonating element arm  78  may be formed from a segment of peripheral conductive housing structures  16 . When operated in a near-field communications mode using near-field communications circuitry  42 , antenna structures  40  of  FIG. 6  form a loop antenna that handles near-field communications signals such as loop current  124 . The loop antenna is formed from a loop-shaped signal path that includes balun inductor  112 , inductor  132 , the segment of arm  78  between terminal  134  and return path  80  (e.g., the segment of peripheral conductive housing structures  16  between terminal  134  and return path  80 ), return path  80 , and antenna ground  88 . 
     In the illustrative configuration of  FIG. 7 , balun  108  is used to couple near-field communications circuit  42  to antenna structures  40  in non-near-field communications antenna return path  80 . As shown in  FIG. 7 , balun  108  includes inductor  114 , which is coupled across the differential signal terminals of near-field communications circuitry  42  and includes inductor  112 , which is interposed within return path  80  and is electromagnetically coupled to inductor  114 . Inductor  140  has a first terminal coupled to antenna resonating element arm  78  (e.g., peripheral conductive housing structures  16 ) at node  142  and a second terminal coupled to antenna ground  88  at node  144 . Inductor  140  spans gap  18 - 1 . At non-near-field communications frequencies, the impedance of inductor  140  is high (i.e., inductor  140  forms an open circuit). At lower frequencies such as those associated with near-field communications, inductor  140  forms a short circuit that electrically couples nodes  142  and  144 . 
     When it is desired to transmit and/or receive near-field communications signals with antenna structures  40  using near-field communications circuitry  42 , loop currents such loop current  124  flow through a near-field communications loop antenna that is formed from inductor  112 , return path  80 , the portion of arm  78  between return path  80  and node  142 , inductor  140  spanning gap  18 - 1 , and a portion of antenna ground  88 . When it is desired to transmit and/or receive non-near-field communications signals with antenna structures  40  using non-near-field communications circuitry  44 , structures  40  can be feed using terminals  84  and  86  in non-near-field communications antenna feed path  82 . 
       FIG. 8  is a diagram of electronic device  10  showing an illustrative configuration that may be used for antenna structures  40  in which balun  108  couples near-field communications circuitry  42  to feed path  82 . As shown in  FIG. 8 , antenna resonating element  76  for a non-near-field communications antenna such as an inverted-F antenna may be formed from antenna resonating element arm  78 , non-near-field communications antenna return path  80 , and non-near-field communications antenna feed path  82 . Non-near-field communications circuitry  44  may be coupled to an antenna feed formed from positive antenna feed terminal  84  and ground antenna feed terminal  86  in antenna feed path  82 . 
     Balun  108  of  FIG. 8  may include inductor  114 , which is coupled across a pair of differential signal terminals (+V, −V) in near-field communications circuitry  42 . Balun  108  may also include inductor  112 . Inductors  112  and  114  may be electromagnetically coupled. As shown in  FIG. 8 , inductor  112  of balun  108  may be interposed within antenna feed path  82 . In particular, inductor  112  may span antenna feed terminals  84  and  86 . A first terminal of inductor  112  may be coupled to positive antenna feed terminal  84  and a second terminal of inductor  112  may be coupled to ground antenna feed terminal  86 . 
     At relatively high non-near-field communications frequencies (e.g., at cellular frequencies, wireless local area network frequencies, etc.), the impedance of inductor  112  will be high and will form an open circuit between terminals  84  and  86 . This allows antenna structures  40  to serve as a non-near-field communications antenna (i.e., an inverted-F antenna formed from resonating element  76  and antenna ground  88 ) for handling wireless communications associated with non-near-field communications circuitry  44 . At lower frequencies such as those associated with near-field communications frequencies, the impedance of inductor  112  will be low, forming a short circuit between terminals  84  and  86 . This allows structures  40  to form a near-field communications loop antenna for handling near-field communications signals transmitted and/or received using near-field communications circuitry  42 . The loop antenna may support loop currents such as loop currents  124 A and/or  126 A. For example, a loop antenna may be formed by inductor  112 , antenna feed path  82 , portions of arm  78 , return path  80 , and antenna ground  88  to support loop currents  124 A and/or a loop antenna may be formed by inductor  112 , antenna feed path  82 , portions of arm  78 , optional inductor  140  spanning gap  18 - 1 , and antenna ground  88 . 
     If desired, balun  108  may be used to couple near-field communications circuitry  42  to antenna structures  40  using portions of an antenna tuning path such as antenna tuning path  150  of  FIG. 9 . In the illustrative configuration of  FIG. 9 , antenna structures  40  include antenna resonating element  76  and antenna ground  88 . Non-near-field communications circuitry  44  is coupled to terminals  84  and  86  in antenna feed path  82 . Near-field communications circuitry  42  is coupled to antenna structures  40  using balun  108 . Balun  108  has an inductor such as inductor  114  that has terminals coupled across a pair of differential signal terminals in near-field communications circuit  42 . Balun  108  also has an inductor such as inductor  112  that is electromagnetically coupled to inductor  114 . In the example of  FIG. 9 , inductor  112  has a first terminal coupled to antenna ground  88  and a second terminal coupled to tunable circuit  152  in antenna tuning path  150 . 
     During operation in non-near-field communications mode, antenna structures  40  form an inverted-F antenna using inverted-F antenna resonating element  76  and antenna ground  88 . Path  80  forms an inverted-F antenna return path between main resonating element arm  78  of inverted-F antenna resonating element  76  and antenna ground  88 . Antenna feed path  82  is coupled in parallel with return path  80  across gap  90 . Antenna tuning path  150  includes tunable circuit  152  (e.g., tunable inductors, capacitors, etc.). Tunable circuitry  152  may be tuned by control circuitry  28  to adjust the performance of the inverted-F antenna in real time (e.g., to tune the resonances of the inverted-F antenna to cover communications bands of interest). In the example of  FIG. 9 , antenna tuning path  150  is coupled across gap  90  in parallel with return path  80  and feed path  82 . This is merely illustrative. Tunable circuitry  152  may be incorporated elsewhere within antenna structures  40 , if desired. 
     During operation in near-field communications mode, antenna structures  40  form a loop antenna for supporting near-field communications signals. The loop antenna may be formed from tuning path  150  (i.e., inductor  112  and tunable circuitry  152 ), resonating element arm  78 , return path  80 , and antenna ground  88 , as illustrated by loop current path  124 A and/or may be formed from tuning path  150  (i.e., inductor  112  and tunable circuitry  152 ), arm  78 , inductor  140  spanning gap  18 - 1 , and antenna ground  88 , as illustrated by loop current path  124 B. A loop antenna may also be formed from tuning path  150  (i.e., inductor  112  and tunable circuitry  152 ), arm  78 , feed path  82 , and antenna ground  88  (e.g., by incorporating an inductor into path  82  across terminals  84  and  86 , as described in connection with  FIG. 8 ). Other configurations for antenna structures  40  may also be used that support the formation of a non-near-field communications antenna that is coupled to non-near-field communications circuitry  44  at non-near-field communications antenna feed terminals  84  and  86  and that support the formation of a near-field communications loop antenna that is coupled to near-field communications circuitry  42  by balun  108 . The configurations of  FIGS. 5, 6, 7, 8, and 9  are merely illustrative. Moreover, additional circuit components (e.g., fixed and/or tunable capacitors and inductors, etc.) may be interposed in antenna structures  40  if desired. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20160316
Publication Date: 20180612
Grant Date: 20180612
Priority Date: 20140303
Inventors: OUYANG, Yuehui
DARNELL, DEAN F.
AYALA VAZQUEZ, ENRIQUE
TONG, ERICA J.
HU, HONGFEI
MOW, MATTHEW A.
PASCOLINI, MATTIA
TSAI, MING-JU
JIN, NANBO
SCHLUB, ROBERT W.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/371", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/48", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/35", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/0081", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q21/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/247", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q21/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/371", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/35", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/247", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/371", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/35", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/48", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B5/26", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B5/26", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 52444632