PATENT DOCUMENT

Publication Number: US-11831090-B2
Application Number: US-202016903198-A
Country: US
Kind Code: B2

Title: Electronic devices with display-overlapping antennas

Abstract:
An electronic device may include a conductive housing with a rear wall and a sidewall. A display may be mounted to the sidewall and may include a conductive display structure separated from the sidewall by a slot. An antenna arm may be interposed between the conductive display structure and the rear wall. A first inductor may couple the conductive display structure to the housing and may compensate for a distributed capacitance between the antenna arm and the conductive display structure. A second inductor may couple the antenna arm to the rear wall and may compensate for a distributed capacitance between the antenna arm and the rear wall. A speaker may be co-located with the antenna. A third inductor may couple the antenna arm to the rear wall to allow antenna currents to bypass the speaker.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a conductive housing having a rear wall and a sidewall; 
 a display mounted to the sidewall, wherein the display comprises a conductive display structure and a display cover layer overlapping the conductive display structure, the conductive display structure being separated from the sidewall by a slot; 
 an antenna arm coupled to the rear wall, wherein the antenna arm is interposed between the rear wall and the conductive display structure, a portion of the antenna arm extending across an area overlaps a portion of the conductive display structure, and the overlapping portions of the antenna arm and the conductive display structure exhibit a distributed capacitance, the antenna arm being configured to radiate through the slot and the display cover layer; and 
 an inductor coupled between the conductive display structure and the conductive housing, wherein the inductor is configured to compensate for the distributed capacitance between the overlapping portions of the antenna arm and the conductive display structure. 
 
     
     
       2. The electronic device of  claim 1 , further comprising:
 an additional inductor coupled between the antenna arm and the rear wall, wherein the additional inductor is configured to compensate for an additional distributed capacitance between the antenna arm and the rear wall. 
 
     
     
       3. The electronic device of  claim 2 , further comprising:
 a dielectric substrate mounted to the rear wall, wherein the antenna arm is on the dielectric substrate; and 
 a conductive structure layered on the dielectric substrate, wherein the conductive structure is configured to form the antenna arm and the additional inductor. 
 
     
     
       4. The electronic device of  claim 3 , wherein the dielectric substrate has a notch, the conductive structure having a portion that is coupled to the rear wall within the notch. 
     
     
       5. The electronic device of  claim 4 , further comprising:
 a speaker mounted to the rear wall within the notch. 
 
     
     
       6. The electronic device of  claim 4 , further comprising:
 an antenna feed coupled to the antenna arm at a point between the notch and the additional inductor, wherein a first segment of the antenna arm from the antenna feed to the additional inductor, the additional inductor, and a first portion of the rear wall form a first current loop path, and wherein a second segment of the antenna arm from a tip of the antenna arm to the portion of the conductive structure, the portion of the conductive structure, and a second portion of the rear wall form a second current loop path, the first and second current loop paths being configured to contribute to a radiative response of the antenna arm. 
 
     
     
       7. The electronic device of  claim 3 , wherein the dielectric substrate has first, second, third, fourth, and fifth sides, the conductive structure has a first portion on the first side that forms the antenna arm, the conductive structure has a second portion on at least some of the second, third, and fourth sides, the second portion forms the additional inductor, and the fifth side and a portion of the fourth side form an aperture for the antenna arm that is not covered by the conductive structure. 
     
     
       8. The electronic device of  claim 7 , wherein the conductive structure comprises conductive tape. 
     
     
       9. The electronic device of  claim 1 , wherein the inductor couples the conductive display structure to the sidewall across the slot. 
     
     
       10. The electronic device of  claim 9 , further comprising:
 conductive tape that couples an end of the inductor to a ledge of the sidewall, wherein the conductive tape is configured to adhere the display cover layer to the sidewall. 
 
     
     
       11. The electronic device of  claim 10 , wherein the conductive tape comprises at least one gap, the electronic device further comprising:
 adhesive on the ledge within the at least one gap, wherein the adhesive is configured to adhere the display cover layer to the sidewall. 
 
     
     
       12. The electronic device of  claim 1 , wherein the inductor couples the conductive display structure to the rear wall. 
     
     
       13. The electronic device of  claim 1 , wherein an entirety of the antenna arm is interposed between the conductive display structure and the rear wall. 
     
     
       14. The electronic device of  claim 1 , further comprising:
 a monopole feed element configured to feed the antenna arm via near-field electromagnetic coupling. 
 
     
     
       15. An electronic device comprising:
 a display having a conductive display structure and a display cover layer overlapping the conductive display structure; 
 a conductive housing wall; 
 a conductive sidewall extending from the conductive housing wall to the display cover layer, wherein a periphery of the conductive display structure is separated from the conductive sidewall by a slot; 
 an interior cavity having opposing edges defined by the conductive display structure and the conductive housing wall; 
 a dielectric substrate mounted to the conductive housing wall within the interior cavity; and 
 a planar inverted-F antenna formed from conductive structures on the dielectric substrate, wherein a first portion of the conductive structures on a top surface of the dielectric substrate is disposed between the conductive display structure and the conductive housing wall, a second portion of the conductive structures on a side surface of the dielectric substrate extends from the first portion of the conductive structures to the conductive housing wall, and the planar inverted-F antenna is configured to convey radio-frequency signals through the slot and the display cover layer. 
 
     
     
       16. The electronic device of  claim 15  further comprising:
 an inductor that couples the conductive display structure to the conductive sidewall across the slot. 
 
     
     
       17. The electronic device of  claim 15 , wherein the first portion of the conductive structures forms a resonating element arm and the second portion of the conductive structures forms a return path for the planar inverted-F antenna that couples the resonating element arm to the conductive housing wall. 
     
     
       18. The electronic device of  claim 15 , wherein the second portion of the conductive structures forms an inductor, the first portion of the conductive structures forms a resonating element arm that extends from the inductor to a tip, and the tip is interposed between the conductive display structure and the conductive housing wall. 
     
     
       19. An electronic device comprising:
 a display having a conductive display structure and a display cover layer overlapping the conductive display structure; 
 a conductive housing wall; 
 a conductive sidewall extending from the conductive housing wall to the display cover layer; 
 an antenna resonating element arm interposed between the conductive display structure and the conductive housing wall; 
 an antenna feed coupled to the antenna resonating element arm and the conductive housing wall; 
 a first inductor that couples an end of the antenna resonating element arm to the conductive housing wall, wherein the first inductor is separated from the antenna feed by a first portion of the antenna resonating element arm and the antenna resonating element arm has a tip opposite the end; 
 a second inductor that couples the antenna resonating element arm to the conductive housing wall, wherein the second inductor is separated from the tip by a second portion of the antenna resonating element arm; and 
 a speaker mounted to the conductive housing wall, wherein the second portion of the antenna resonating element arm extends along two opposing sides of the speaker. 
 
     
     
       20. The electronic device of  claim 19 , wherein a periphery of the conductive display structure is separated from the conductive sidewall by a slot, the first portion of the antenna resonating element arm, the first inductor, and a first portion of the conductive housing wall form a first current loop path, the second portion of the antenna resonating element arm, the second inductor, and a second portion of the conductive housing wall form a second current loop path, and the first and second current loop paths are configured to radiate radio-frequency signals through the slot and the display cover layer.

Description:
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. 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. 
     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 with satisfactory efficiency bandwidth. 
     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 a housing, a display, and wireless circuitry. The wireless circuitry may include one or more antennas. The housing may include a conductive sidewall and a conductive rear wall. The display may include a conductive display structure and a display cover layer overlapping the conductive display structure. The display may be mounted to the conductive sidewall. A periphery of the conductive display structure may be separated from the conductive sidewall by a slot. The conductive display structure and the conductive rear wall may define opposing edges of an interior cavity of the device. 
     A dielectric substrate may be mounted to the conductive rear wall within the interior cavity. A planar inverted-F antenna may be formed from a conductive structure layered over the dielectric substrate. An entirety of the planar inverted-F antenna may be interposed between the conductive display structure and the conductive rear wall, if desired. The antenna may have an antenna arm formed on a top surface of the dielectric substrate. A first inductor may be coupled between the conductive display structure and the housing. The first inductor may compensate for detuning of the antenna by a distributed capacitance between the antenna arm and the conductive display structure. The antenna arm may be coupled to the conductive rear wall by a second inductor. The second inductor may compensate for detuning of the antenna by a distributed capacitance between the antenna arm and the conductive rear housing wall. The antenna may radiate through the slot and the display cover layer. 
     If desired, the antenna may include a third inductor that couples the antenna arm to the conductive rear housing wall. A first portion of the antenna arm, the second inductor, and a first portion of the conductive rear housing wall may form a first current loop path for the antenna. A second portion of the antenna arm, the third inductor, and a second portion of the conductive rear housing wall may form a second current loop path for the antenna. The first and second current loop paths may contribute to the radiative response of the antenna. A device component such as a speaker may be co-located with the antenna. The speaker may be mounted within a notch in the dielectric substrate. The second portion of the antenna arm may extend along opposing sides of the speaker. The second and third inductors and the antenna arm may be formed from respective portions of the conductive structure layered over the dielectric substrate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an illustrative electronic device in accordance with some embodiments. 
         FIG.  2    is a schematic diagram of illustrative circuitry in an electronic device in accordance with some embodiments. 
         FIG.  3    is a schematic diagram of illustrative inverted-F antenna structures in accordance with some embodiments. 
         FIG.  4    is a top-down view of an illustrative electronic device having multiple antennas at different locations around a display in accordance with an embodiment. 
         FIG.  5    is a cross-sectional side view of an illustrative antenna having a resonating element arm between a conductive display module and a conductive rear housing wall in accordance with some embodiments. 
         FIG.  6    is a top-down view of illustrative grounding structures having openings to accommodate adhesive for securing a display cover layer to a housing wall in accordance with some embodiments. 
         FIG.  7    is a perspective view of an illustrative antenna of the type shown in  FIG.  5    having a monopole feed element in accordance with some embodiments. 
         FIG.  8    is a cross-sectional side view of an illustrative antenna having multiple current loop paths to accommodate a device component in accordance with some embodiments. 
         FIG.  9    is a perspective view of an illustrative antenna of the type shown in  FIG.  8    in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     An electronic device such as electronic device  10  of  FIG.  1    may be provided with wireless circuitry that includes antennas. The antennas may be used to transmit and/or receive wireless radio-frequency signals. 
     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 handheld device such as a cellular telephone, a media player, or other small portable device. Device  10  may also be a set-top box, a desktop computer, a display into which a computer or other processing circuitry has been integrated, a display without an integrated computer, a wireless access point, wireless base station, an electronic device incorporated into a kiosk, building, or vehicle, 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 (e.g., glass, ceramic, plastic, sapphire, etc.). 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 be mounted on the front face of device  10 . Display  14  may be a touch screen that incorporates capacitive touch electrodes or may be insensitive to touch. The rear face of housing  12  (i.e., the face of device  10  opposing the front face of device  10 ) may have a substantially planar housing wall such as rear housing wall  12 R (e.g., a planar housing wall). Rear housing wall  12 R may have slots that pass entirely through the rear housing wall and that therefore separate portions of housing  12  from each other. Rear housing wall  12 R may include conductive portions and/or dielectric portions. If desired, rear housing wall  12 R may include a planar metal layer covered by a thin layer or coating of dielectric such as glass, plastic, sapphire, or ceramic. Housing  12  may also have shallow grooves that do not pass entirely through housing  12 . The slots and grooves may be filled with plastic or other dielectric. If desired, portions of housing  12  that have been separated from each other (e.g., by a through slot) may be joined by internal conductive structures (e.g., sheet metal or other metal members that bridge the slot). 
     Housing  12  may include peripheral housing structures such as peripheral structures  12 W. Peripheral structures  12 W and rear housing wall  12 R may sometimes be referred to herein collectively as conductive structures of housing  12 . Peripheral structures  12 W may run around the periphery of device  10  and display  14 . In configurations in which device  10  and display  14  have a rectangular shape with four edges, peripheral structures  12 W may be implemented using peripheral housing structures that have a rectangular ring shape with four corresponding edges and that extend from rear housing wall  12 R to the front face of device  10  (as an example). Peripheral structures  12 W or part of peripheral structures  12 W may serve as a bezel for display  14  (e.g., a cosmetic trim that surrounds all four sides of display  14  and/or that helps hold display  14  to device  10 ) if desired. Peripheral structures  12 W may, if desired, form sidewall structures for device  10  (e.g., by forming a metal band with vertical sidewalls, curved sidewalls, etc.). 
     Peripheral structures  12 W may be formed of a conductive material such as metal and may therefore sometimes be referred to as conductive sidewalls, peripheral conductive housing structures, conductive housing structures, peripheral metal structures, peripheral conductive sidewalls, peripheral conductive sidewall structures, conductive housing sidewalls, peripheral conductive housing sidewalls, sidewalls, sidewall structures, or a peripheral conductive housing member (as examples). Conductive sidewalls  12 W may be formed from a metal such as stainless steel, aluminum, or other suitable materials. One, two, or more than two separate structures may be used in forming conductive sidewalls  12 W. 
     It is not necessary for conductive sidewalls  12 W to have a uniform cross-section. For example, the top portion of conductive sidewalls  12 W may, if desired, have an inwardly protruding lip that helps hold display  14  in place. The bottom portion of conductive sidewalls  12 W may also have an enlarged lip (e.g., in the plane of the rear surface of device  10 ). Conductive sidewalls  12 W may have substantially straight vertical sidewalls, may have sidewalls that are curved, or may have other suitable shapes. In some configurations (e.g., when conductive sidewalls  12 W serve as a bezel for display  14 ), conductive sidewalls  12 W may run around the lip of housing  12  (i.e., conductive sidewalls  12 W may cover only the edge of housing  12  that surrounds display  14  and not the rest of the sidewalls of housing  12 ). 
     If desired, rear housing wall  12 R may be formed from a metal such as stainless steel or aluminum and may sometimes be referred to herein as conductive rear housing wall  12 R or conductive rear wall  12 R. Conductive rear housing wall  12 R may lie in a plane that is parallel to display  14 . In configurations for device  10  in which the rear housing wall is formed from metal, it may be desirable to form parts of conductive sidewalls  12 W as integral portions of the housing structures forming the conductive rear housing wall of housing  12 . For example, conductive rear housing wall  12 R of device  10  may be formed from a planar metal structure and portions of conductive sidewalls  12 W on the sides of housing  12  may be formed as flat or curved vertically extending integral metal portions of the planar metal structure (e.g., housing structures  12 R and  12 W may be formed from a continuous piece of metal in a unibody configuration). Housing structures such as these may, if desired, be machined from a block of metal and/or may include multiple metal pieces that are assembled together to form housing  12 . Conductive rear housing wall  12 R may have one or more, two or more, or three or more portions. Conductive sidewalls  12 W and/or the conductive rear housing wall  12 R may form one or more exterior surfaces of device  10  (e.g., surfaces that are visible to a user of device  10 ) and/or may be implemented using internal structures that do not form exterior surfaces of device  10  (e.g., conductive housing structures that are not visible to a user of device  10  such as conductive structures that are covered with layers such as thin cosmetic layers, protective coatings, and/or other coating layers that may include dielectric materials such as glass, ceramic, plastic, or other structures that form the exterior surfaces of device  10  and/or serve to hide structures  12 W and/or  12 R from view of the user). 
     Display  14  may have an array of pixels that form an active area AA that displays images for a user of device  10 . For example, active area AA may include an array of display pixels. The array of pixels may be formed from liquid crystal display (LCD) components, an array of electrophoretic pixels, an array of plasma display pixels, an array of organic light-emitting diode display pixels or other light-emitting diode pixels, an array of electrowetting display pixels, or display pixels based on other display technologies. If desired, active area AA may include touch sensors such as touch sensor capacitive electrodes, force sensors, or other sensors for gathering a user input. 
     Display  14  may have an inactive border region that runs along one or more of the edges of active area AA. Inactive area IA may be free of pixels for displaying images and may overlap circuitry and other internal device structures in housing  12 . To block these structures from view by a user of device  10 , the underside of the display cover layer or other layers in display  14  that overlap inactive area IA may be coated with an opaque masking layer in inactive area IA. The opaque masking layer may have any suitable color. 
     Display  14  may be protected using a display cover layer such as a layer of transparent glass, clear plastic, transparent ceramic, sapphire, or other transparent crystalline material, or other transparent layer(s). The display cover layer may have a planar shape, a convex curved profile, a shape with planar and curved portions, a layout that includes a planar main area surrounded on one or more edges with a portion that is bent out of the plane of the planar main area, or other suitable shapes. The display cover layer may cover the entire front face of device  10 . In another suitable arrangement, the display cover layer may cover substantially all of the front face of device  10  or only a portion of the front face of device  10 . Openings may be formed in the display cover layer. For example, an opening may be formed in the display cover layer to accommodate a button. An opening may also be formed in the display cover layer to accommodate ports such as speaker port  8  or a microphone port. Speaker port  8  may be omitted if desired. Openings may be formed in housing  12  to form communications ports (e.g., an audio jack port, a digital data port, etc.) and/or audio ports for audio components such as a speaker and/or a microphone if desired. 
     Display  14  may include a display module having conductive structures such as an array of capacitive electrodes for a touch sensor, conductive lines for addressing pixels, driver circuits, etc. Housing  12  may include internal conductive structures such as metal frame members and a planar conductive housing member (sometimes referred to as a backplate) that spans the walls of housing  12  (i.e., a substantially rectangular sheet formed from one or more metal parts that is welded or otherwise connected between opposing sides of conductive sidewalls  12 W). The backplate may form an exterior rear surface of device  10  or may be covered by layers such as thin cosmetic layers, protective coatings, and/or other coatings that may include dielectric materials such as glass, ceramic, plastic, or other structures that form the exterior surfaces of device  10  and/or serve to hide the backplate from view of the user. Device  10  may also include conductive structures such as printed circuit boards, components mounted on printed circuit boards, and other internal conductive structures. These conductive structures, which may be used in forming a ground plane in device  10 , may extend under active area AA of display  14 , for example. 
     At ends (regions)  16  and  20 , openings may be formed within the conductive structures of device  10  (e.g., between conductive sidewalls  12 W and opposing conductive ground structures such as conductive portions of conductive rear housing wall  12 R, conductive traces on a printed circuit board, conductive electrical components in display  14 , etc.). These openings, which may sometimes be referred to as gaps, may be filled with air, plastic, and/or other dielectrics and may be used in forming slot antenna resonating elements for one or more antennas in device  10 , if desired. 
     Conductive housing structures and other conductive structures in device  10  may serve as a ground plane for the antennas in device  10 . The openings in ends  20  and  16  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 from the ground plane, may contribute to the performance of a parasitic antenna resonating element, or may otherwise serve as part of antenna structures formed in ends  20  and  16 . If desired, the ground plane that is under active area AA of display  14  and/or other metal structures in device  10  may have portions that extend into parts of the ends of device  10  (e.g., the ground may extend towards the dielectric-filled openings in ends  20  and  16 ), thereby narrowing the slots in ends  20  and  16 . 
     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 (e.g., at ends  20  and  16  of device  10  of  FIG.  1   ), 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 these locations. The arrangement of  FIG.  1    is merely illustrative. 
     Portions of conductive sidewalls  12 W may be provided with peripheral gap structures. For example, conductive sidewalls  12 W may be provided with one or more gaps such as gaps  18 , as shown in  FIG.  1   . The gaps in conductive sidewalls  12 W may be filled with dielectric such as polymer, ceramic, glass, air, other dielectric materials, or combinations of these materials. Gaps  18  may divide conductive sidewalls  12 W into one or more peripheral conductive segments. There may be, for example, two peripheral conductive segments in conductive sidewalls  12 W (e.g., in an arrangement with two of gaps  18 ), three peripheral conductive segments (e.g., in an arrangement with three of gaps  18 ), four peripheral conductive segments (e.g., in an arrangement with four of gaps  18 ), six peripheral conductive segments (e.g., in an arrangement with six gaps  18 ), etc. The segments of conductive sidewalls  12 W that are formed in this way may form parts of antennas in device  10 . 
     If desired, openings in housing  12  such as grooves that extend partway or completely through housing  12  may extend across the width of the rear wall of housing  12  and may penetrate through the rear wall of housing  12  to divide the rear wall into different portions. These grooves may also extend into conductive sidewalls  12 W and may form antenna slots, gaps  18 , and other structures in device  10 . Polymer or other dielectric may fill these grooves and other housing openings. In some situations, housing openings that form antenna slots and other structures may be filled with a dielectric such as air. 
     In a typical scenario, device  10  may have one or more upper antennas and one or more lower antennas (as an example). An upper antenna may, for example, be formed at upper end  16  of device  10 . A lower antenna may, for example, be formed at lower end  20  of device  10 . 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 local area network communications, voice and data cellular telephone communications, global positioning system (GPS) communications or other satellite navigation system communications, Bluetooth® communications, near-field communications, etc. 
     In order to provide an end user of device  10  with as large of a display as possible (e.g., to maximize an area of the device used for displaying media, running applications, etc.), it may be desirable to increase the amount of area at the front face of device  10  that is covered by active area AA of display  14 . Increasing the size of active area AA may reduce the size of inactive area IA within device  10 . This may reduce the area of ends  20  and  16  that is available for forming antennas within device  10 . In general, antennas that are provided with larger operating volumes or spaces may have higher bandwidth efficiency than antennas that are provided with smaller operating volumes or spaces. If care is not taken, increasing the size of active area AA may reduce the operating space available to the antennas, which can undesirably inhibit the efficiency bandwidth of the antennas (e.g., such that the antennas no longer exhibit satisfactory radio-frequency performance). It would therefore be desirable to be able to provide antennas that occupy a small amount of space within device  10  (e.g., to allow for as large of a display active area AA as possible) while still allowing the antennas to operate with optimal efficiency bandwidth. 
     A schematic diagram of illustrative components that may be used in device  10  is shown in  FIG.  2   . As shown in  FIG.  2   , device  10  may include control circuitry  24 . Control circuitry  24  may include storage such as storage circuitry  28 . Storage circuitry  28  may include 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. 
     Control circuitry  24  may include processing circuitry such as processing circuitry  26 . Processing circuitry  26  may be used to control the operation of device  10 . Processing circuitry  26  may include on one or more microprocessors, microcontrollers, digital signal processors, host processors, baseband processor integrated circuits, application specific integrated circuits, central processing units (CPUs), etc. Control circuitry  24  may be configured to perform operations in device  10  using hardware (e.g., dedicated hardware or circuitry), firmware, and/or software. Software code for performing operations in device  10  may be stored on storage circuitry  28  (e.g., storage circuitry  28  may include non-transitory (tangible) computer readable storage media that stores the software code). The software code may sometimes be referred to as program instructions, software, data, instructions, or code. Software code stored on storage circuitry  28  may be executed by processing circuitry  26 . 
     Control circuitry  24  may be used to run software on device  10  such as satellite navigation applications, 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, control circuitry  24  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  24  include internet protocols, wireless local area network (WLAN) protocols (e.g., IEEE 802.11 protocols—sometimes referred to as Wi-Fi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol or other wireless personal area network (WPAN) protocols, IEEE 802.11ad protocols, cellular telephone protocols, MIMO protocols, antenna diversity protocols, satellite navigation system protocols (e.g., global positioning system (GPS) protocols, global navigation satellite system (GLONASS) protocols, etc.), or any other desired communications protocols. Each communications protocol may be associated with a corresponding radio access technology (RAT) that specifies the physical connection methodology used in implementing the protocol. 
     Device  10  may include input-output circuitry  30 . Input-output circuitry  30  may include input-output devices  32 . Input-output devices  32  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 devices  32  may include user interface devices, data port devices, and other input-output components. For example, input-output devices  32  may include touch sensors, displays (e.g., touch-sensitive displays), light-emitting components such as displays without touch sensor capabilities, buttons (mechanical, capacitive, optical, etc.), scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, audio jacks and other audio port components, digital data port devices, motion sensors (accelerometers, gyroscopes, and/or compasses that detect motion), capacitance sensors, proximity sensors, magnetic sensors, force sensors (e.g., force sensors coupled to a display to detect pressure applied to the display), etc. In some configurations, keyboards, headphones, displays, pointing devices such as trackpads, mice, and joysticks, and other input-output devices may be coupled to device  10  using wired or wireless connections (e.g., some of input-output devices  32  may be peripherals that are coupled to a main processing unit or other portion of device  10  via a wired or wireless link). 
     Input-output circuitry  30  may include wireless circuitry  34  to support wireless communications. Wireless circuitry  34  may include radio-frequency (RF) transceiver circuitry  36  formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas such as antenna  40 , transmission lines such as transmission line  38 , and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). While control circuitry  24  is shown separately from wireless circuitry  34  in the example of  FIG.  1    for the sake of clarity, wireless circuitry  34  may include processing circuitry that forms a part of processing circuitry  26  and/or storage circuitry that forms a part of storage circuitry  28  of control circuitry  24  (e.g., portions of control circuitry  24  may be implemented on wireless circuitry  34 ). As an example, control circuitry  24  (e.g., processing circuitry  26 ) may include baseband processor circuitry or other control components that form a part of wireless circuitry  34 . 
     Radio-frequency transceiver circuitry  36  may include wireless local area network transceiver circuitry that handles 2.4 GHz and 5 GHz bands for Wi-Fi® (IEEE 802.11) or other WLAN communications bands. Radio-frequency transceiver circuitry  36  may include wireless personal area network transceiver circuitry that handles the 2.4 GHz Bluetooth® communications band or other WPAN communications bands. If desired, radio-frequency transceiver circuitry  36  may handle other bands such as cellular telephone bands, near-field communications bands (e.g., at 13.56 MHz), millimeter or centimeter wave bands (e.g., communications at 10-300 GHz), and/or other communications bands. If desired, radio-frequency transceiver circuitry  36  may also include ultra-wideband (UWB) transceiver circuitry that supports communications using the IEEE 802.15.4 protocol and/or other ultra-wideband communications protocols. Communications bands may sometimes be referred to herein as frequency bands or simply as “bands” and may span corresponding ranges of frequencies. 
     Wireless circuitry  34  may include one or more antennas such as antenna  40 . In general, radio-frequency transceiver circuitry  36  may be configured to cover (handle) any suitable communications (frequency) bands of interest. Radio-frequency transceiver circuitry  36  may convey radio-frequency signals using antennas  40  (e.g., antennas  40  may convey the radio-frequency signals for radio-frequency transceiver circuitry  36 ). The term “convey radio-frequency signals” as used herein means the transmission and/or reception of the radio-frequency signals (e.g., for performing unidirectional and/or bidirectional wireless communications with external wireless communications equipment). Antennas  40  may transmit the radio-frequency signals by radiating the radio-frequency signals into free space (or to freespace through intervening device structures such as a dielectric cover layer). Antennas  40  may additionally or alternatively receive the radio-frequency signals from free space (e.g., through intervening devices structures such as a dielectric cover layer). The transmission and reception of radio-frequency signals by antennas  40  each involve the excitation or resonance of antenna currents on an antenna resonating element in the antenna by the radio-frequency signals within the frequency band(s) of operation of the antenna. 
     As shown in  FIG.  2   , radio-frequency transceiver circuitry  36  may be coupled to antenna feed  42  of antenna  40  using transmission line  38 . Antenna feed  42  may include a positive antenna feed terminal such as positive antenna feed terminal  44  and may include a ground antenna feed terminal such as ground antenna feed terminal  46 . Transmission line  38  may be formed from metal traces on a printed circuit, cables, or other conductive structures. Transmission line  38  may have a positive transmission line signal path such as path  48  that is coupled to positive antenna feed terminal  44 . Transmission line  38  may have a ground transmission line signal path such as path  50  that is coupled to ground antenna feed terminal  46 . Path  48  may sometimes be referred to herein as signal conductor  48  and path  50  may sometimes be referred to herein as ground conductor  50 . 
     Transmission line paths such as transmission line  38  may be used to route antenna signals within device  10  (e.g., to convey radio-frequency signals between radio-frequency transceiver circuitry  36  and antenna feed  42  of antenna  40 ). Transmission lines in device  10  may include coaxial cables, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, transmission lines formed from combinations of transmission lines of these types, etc. Transmission lines in device  10  such as transmission line  38  may be integrated into rigid and/or flexible printed circuit boards. In one suitable arrangement, transmission lines such as transmission line  38  may also include transmission line conductors (e.g., signal conductors  48  and ground conductors  50 ) integrated within multilayer laminated structures (e.g., layers of a conductive material such as copper and a dielectric material such as a resin that are laminated together without intervening adhesive). The multilayer laminated structures may, if desired, be folded or bent in multiple dimensions (e.g., two or three dimensions) and may maintain a bent or folded shape after bending (e.g., the multilayer laminated structures may be folded into a particular three-dimensional shape to route around other device components and may be rigid enough to hold its shape after folding without being held in place by stiffeners or other structures). All of the multiple layers of the laminated structures may be batch laminated together (e.g., in a single pressing process) without adhesive (e.g., as opposed to performing multiple pressing processes to laminate multiple layers together with adhesive). 
     Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be interposed within the paths formed using transmission lines such as transmission line  38  and/or circuits such as these may be incorporated into antenna  40  (e.g., to support antenna tuning, to support operation in desired frequency bands, etc.). During operation, control circuitry  24  may use radio-frequency transceiver circuitry  36  and antenna(s)  40  to transmit and/or receive data wirelessly. Control circuitry  24  may, for example, receive wireless local area network communications wirelessly using radio-frequency transceiver circuitry  36  and antenna(s)  40  and may transmit wireless local area network communications wirelessly using radio-frequency transceiver circuitry  36  and antenna(s)  40 . 
     Antennas such as antenna  40  may be formed using any suitable antenna types. For example, antennas in device  10  may include antennas with resonating elements that are formed from loop antenna structures, patch antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, helical antenna structures, monopole antenna structures, strip antenna structures, dipole antenna structures, hybrids of these designs, etc. Parasitic elements may be included in antennas  40  to adjust antenna performance. If desired, antenna  40  may be provided with a conductive cavity that backs the antenna resonating element of antenna  40  (e.g., antenna  40  may be a cavity-backed antenna such as a cavity-backed slot antenna). 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 antenna. In some configurations, different antennas may be used in handling different bands for radio-frequency transceiver circuitry  36 . Alternatively, a given antenna  40  may cover one or more bands. 
     In one suitable arrangement that is sometimes described herein as an example, planar inverted-F antenna structures may be used for implementing antennas  40 . Antennas that are implemented using planar inverted-F antenna structures may sometimes be referred to herein as planar inverted-F antennas.  FIG.  3    is a schematic diagram of inverted-F antenna structures that may be used to form antenna  40 . As shown in  FIG.  3   , antenna  40  may include an antenna resonating element such as antenna resonating element  52  and an antenna ground such as antenna ground  56 . Antenna resonating element  52  may include a resonating element arm  54  (sometimes referred to herein as antenna resonating element arm  54 , radiating arm  54 , radiating element arm  54 , or arm  54 ) that is shorted to antenna ground  56  by return path  55 . Antenna  40  may be fed by coupling a transmission line (e.g., transmission line  38  of  FIG.  3   ) to positive antenna feed terminal  44  and ground antenna feed terminal  46  of antenna feed  42 . Positive antenna feed terminal  44  may be coupled to resonating element arm  54  and ground antenna feed terminal  46  may be coupled to antenna ground  56 . Return path  55  may be coupled between resonating element arm  54  and antenna ground  56  in parallel with antenna feed  42 . 
     The length of resonating element arm  54  may determine the response (e.g., resonant) frequency of the antenna. For example, the length of resonating element arm  54  may be approximately equal to (e.g., within 15% of) one-quarter of an effective wavelength corresponding to a frequency in the frequency band of operation of antenna  40  (e.g., where the effective wavelength is equal to a free space wavelength multiplied by a constant value associated with the dielectric material surrounding antenna  40 ). In the example of  FIG.  3   , antenna  40  includes only a single resonating element arm  54 . This is merely illustrative. If desired, antenna  40  may include any desired number of resonating element arms or branches having any desired shapes and following any desired paths (e.g., for conveying signals in multiple frequency bands). Resonating element arm  54  may be formed using a conductive structure (e.g., a conductive trace or patch, sheet metal, conductive foil, etc.) that extends across a surface (e.g., a planar lateral area) above antenna ground  56  (e.g., resonating element arm  54  may have a width measured into and out of the plane of the page of  FIG.  3   ), such that resonating element arm  54  forms a planar resonating element arm. In these scenarios, the inverted-F antenna structures of  FIG.  3    form planar inverted-F antenna structures. 
       FIG.  4    is a top-down view of device  10  showing different regions of device  10  that can be used to form antennas  40 . As shown in  FIG.  4   , device  10  may include display  14 . Display  14  may have a display module that is covered by a transparent display cover layer. The display module may emit light (e.g., images) through the display cover layer and/or may receive touch and/or force sensor input through the display cover layer. The display cover layer may be formed from glass, sapphire, plastic, or other materials. The display module may include stacked dielectric layers having pixel circuitry, touch sensor electrodes, force sensor circuitry, and/or other active components associated with emitting light and/or receiving input through the display cover layer. The display module may include conductive display structures such as conductive display structures  62  of  FIG.  4    (e.g., conductive display structures  62  may form the display module for display  14 ). The display cover layer of display  14  is omitted from the example of  FIG.  4    for the sake of clarity. 
     As shown in  FIG.  4   , conductive display structures  62  may be separated from conductive sidewalls  12 W of device  10  by slots (gaps)  64 . Slots  64  may, for example, define inactive area IA of display  14  ( FIG.  1   ). Conductive display structures  62  may include a conductive frame for the active components of display  14 , conductive layers in the display module (e.g., a conductive backplate for the display module or conductive layers embedded within the dielectric layers of the display module), conductive shielding structures, ground layers in display  14 , and/or other conductive structures in display  14 . If desired, conductive display structures  62  may include portions of the pixel circuitry, touch sensor circuitry, force sensor circuitry, and/or other components in the display module for display  14 . Conductive display structures  62  may laterally extend across active area AA of  FIG.  1   , for example. As active area AA of display  14  is maximized, the space within device  10  occupied by the display module and conductive display structures  62  is also maximized, thereby limiting the amount of space available within device  10  for forming antennas  40 . 
     Antennas  40  ( FIG.  2   ) may be formed at upper end  16  of device  10  if desired. For example, device  10  may include a first antenna  40  within region  58  of upper end  16  and may include a second antenna  40  within region  60  of upper end  16 . Regions  58  and  60  (e.g., antennas  40 ) may additionally or alternatively be located at lower end  20  or elsewhere on device  10  if desired. In general, device  10  may include any desired number of antennas  40  formed within any desired number of regions such as regions  58  and  60 , at any desired locations around the periphery of device  10 . Conductive sidewalls  12 W may be used in forming antenna ground  56  ( FIG.  3   ) for the antennas  40  within regions  58  and  60 . 
     In practice, larger antenna volumes allow for greater antenna efficiency bandwidth. At the same time, larger slots  64  may increase the aperture size for the antennas, thereby increasing the overall antenna efficiency in radiating through slots  64  and the front face of device  10 . As the size of active area AA ( FIG.  1   ) increases, the size of slots  64  and thus the volume (e.g., aperture size) of the antennas decreases. Conductive display structures  62  may overlap and/or may be in close proximity to the antennas within regions  58  and  60 . As the size of slots  64  is relatively small, the antennas located within regions  58  and  60  may have resonating element arms that at least partially overlap conductive display structures  62 . 
     However, if care is not taken, conductive display structures  62  overlapping the antenna resonating element arms may undesirably block some of the radio-frequency signals conveyed by the antennas, particularly through display  14 . This can reduce the efficiency and bandwidth of the antennas through the front face of device  10 . In order to mitigate these effects, conductive display structures  62  may be coupled to ground (e.g., antenna ground  56  of  FIG.  32   ) at one or more locations overlapping each antenna (e.g., within regions  58  and  60  of  FIG.  4   ). 
     Conductive grounding structures such as grounding structures  66  may be used to couple conductive display structures  62  to conductive sidewalls  12 W at one or more locations within regions  58  and  60  (e.g., overlapping each antenna aperture). Grounding structures  66  may have a first terminal coupled to conductive sidewalls  12 W and a second terminal coupled to conductive display structures  62  (e.g., grounding structures  66  may bridge slot  64  and may overlap the antenna aperture for a corresponding antenna  40 ). This may couple the portion of conductive display structures  62  adjacent to each antenna aperture to a ground potential (e.g., antenna ground  56  of  FIG.  3   ), thereby allowing radio-frequency signals for the antennas to pass through display  14  without being substantially blocked by conductive display structures  62 . 
     Grounding structures  66  may overlap any desired locations within the antennas  40  of regions  58  and  60 . In the example of  FIG.  4   , a single grounding structure  66  couples conductive display structures  62  to conductive sidewalls  12 W within region  58  whereas two grounding structures  66  couple different locations on conductive display structures  62  to conductive sidewalls  12 W within region  60 . This is merely illustrative. Regions  58  and  60  may include any desired number of grounding structures  66 . Grounding structures  66  may each include conductive wire, sheet metal, conductive foam, conductive adhesive, conductive fabric structures such as air loop gaskets, welds, solder, conductive screws, conductive springs, conductive pins, conductive tape, conductive portions of other device components such as conductive portions of a device switch (e.g., a volume or ringer switch), conductive portions of a camera module or camera bracket, conductive portions of a sensor module or sensor bracket, conductive portions of a speaker or speaker bracket, and/or any other desired conductive structures. 
       FIG.  5    is a cross-sectional side view of device  10  showing how a given antenna  40  may be formed within region  60  of device  10  (e.g., as taken along line AA′ of  FIG.  4   ). This is merely illustrative and, in another suitable arrangement, the antenna of  FIG.  5    may be located within region  58  of  FIG.  4    or elsewhere in device  10 . As shown in  FIG.  5   , display  14  may include display cover layer  67  overlapping conductive display structures  62  (e.g., conductive display structures  62  may be mounted to the inner surface of display cover layer  67 ). Display cover layer  67  may be transparent and may be formed from any desired materials such as glass, plastic, or sapphire. Portions of display cover layer  67  may be provided with an opaque masking layer such as an ink layer if desired. 
     Display  14  may be mounted to conductive sidewalls  12 W, one of which is illustrated in  FIG.  5   . Conductive sidewall  12 W may have an inwardly-protruding portion (extension)  74  that is sometimes referred to herein as ledge  74  or datum  74 . Ledge  74  may have a lateral surface that extends parallel to the inner surface of display cover layer  67 . Display  14  may be secured to conductive sidewall  12 W by coupling display cover layer  67  to ledge  74  using adhesive material. 
     Conductive display structures  62  may be separated from conductive rear housing wall  12 R by interior cavity  68 . Interior cavity  68  may be a conductive cavity having (conductive) edges defined by the conductive material in conductive rear housing wall  12 R and conductive display structures  62 . The lateral periphery of conductive display structures  62  may be separated from conductive sidewall  12 W by a corresponding slot  64  (e.g., inactive area IA of  FIG.  1   ). The antenna resonating element  52  for antenna  40  may be mounted within interior cavity  68  (e.g., resonating element arm  54  may be located within interior cavity  68 ). 
     Antenna feed  42  may be coupled between resonating element arm  54  and conductive rear housing wall  12 R (e.g., across a portion of interior cavity  68 ). Positive antenna feed terminal  44  may be coupled to resonating element arm  54  whereas ground antenna feed terminal  46  is coupled to conductive rear housing wall  12 R. Conductive rear housing wall  12 R and conductive sidewall  12 W may form the antenna ground for antenna  40  (e.g., antenna ground  56  of  FIG.  3   ). An inductor such as inductor  70  may couple an end of resonating element arm  54  to ground (e.g., conductive rear housing wall  12 R). Inductor  70  may form a return path for antenna resonating element  52  (e.g., return path  55  of  FIG.  3   ). Resonating element arm  54  may extend from inductor  70  to an opposing tip  76 . Antenna feed  42  may be coupled to resonating element arm  54  between tip  76  and inductor  70 . Resonating element arm  54  may completely or partially overlap conductive display structures  62  such that some or all of antenna resonating element  52  is interposed within interior cavity  68  between conductive display structures  62  and conductive rear housing wall  12 R (e.g., tip  76  may overlap conductive display structures  62  or may overlap slot  64 ). 
     If care is not taken, the presence of conductive display structures  62  may block antenna  40  from radiating through the front face of device  10 , thereby limiting the overall antenna efficiency for antenna  40  through the front face of device  10 . However, the presence of slot  64  may allow antenna  40  to convey radio-frequency signals  78  between interior cavity  68  and the free space exterior to device  10  (e.g., antenna  40  may transmit and/or receive radio-frequency signals  78  through slot  64  and display cover layer  67 ). If desired, interior cavity  68  may form a conductive cavity-back for antenna  40  that helps to optimize the radiation pattern and efficiency for antenna  40 . 
     Resonating element arm  54  may extend across a lateral area that lies within the X-Y plane of  FIG.  5    (e.g., resonating element arm  54  may be a planar inverted-F antenna resonating element arm). In practice, the lateral area of resonating element arm  54  may extend parallel to the bottom surface of conductive display structures  62 . This may form a distributed capacitance such as distributed capacitance CA between resonating element arm  54  and conductive display structures  62 . At the same time, an additional distributed capacitance CB may be present between resonating element arm  54  and conductive rear housing wall  12 R. If care is not taken, distributed capacitance CA and/or distributed capacitance CB may undesirably detune the frequency response of antenna  40  (e.g., away from the frequency band of operation for antenna  40 ). 
     In order to mitigate the effects of distributed capacitance CA on the frequency response of antenna  40 , an inductor such as inductor  72  may be coupled between conductive display structures  62  and conductive sidewall  12 W. In this way, inductor  72  may be used to form a corresponding grounding structure  66  for antenna  40 . The inductance of inductor  72  may be selected to cancel out the effects of distributed capacitance CA on antenna  40 . Similarly, the inductance of inductor  70  may be selected to mitigate the effects of distributed capacitance CB on the frequency response of antenna  40 . Inductors  70  and  72  may be formed from discrete components (e.g., discrete inductors such as surface mount inductors), segments of conductive material that exhibit a desired inductance, etc. Inductors  70  and/or  72  may include multiple inductors coupled in series and/or in parallel if desired. By compensating for the effects of distributed capacitances CA and CB, antenna  40  may convey radio-frequency signals  78  through slot  64  and display cover layer  67  with satisfactory antenna efficiency across the entire frequency band of operation for antenna  40 . 
     Grounding structure  66  may be coupled to ledge  74  of conductive sidewall  12 W if desired.  FIG.  6    is a top down view showing how grounding structure  66  may be coupled to ledge  74  (e.g., taken in the direction of arrow  80  of  FIG.  5   ). Display cover layer  67  of  FIG.  5    has been omitted from  FIG.  6    for the sake of clarity. 
     As shown in  FIG.  6   , grounding structure  66  may include one or more strips of conductive adhesive  82 . Conductive adhesive  82  may be, for example, conductive tape having one or two adhesive sides (surfaces). Conductive adhesive  82  may have a first end coupled to conductive display structures  62  ( FIG.  5   ) and an opposing second end coupled to ledge  74  of conductive sidewall  12 W. If desired, the first end of conductive adhesive  82  may be coupled to a terminal of inductor  72  ( FIG.  5   ). In another suitable arrangement, conductive adhesive  82  may exhibit an inductance that is selected so that conductive adhesive  82  itself forms inductor  72  of  FIG.  5   . Conductive adhesive  82  (e.g., grounding structure  66 ) may form a conductive path to ground from conductive display structures  62  ( FIG.  5   ). The second end of conductive adhesive  82  may help to secure (adhere) display cover layer  67  ( FIG.  5   ) to conductive sidewall  12 W. In this way, grounding structure  66  may optimize antenna efficiency and bandwidth through slot  64  for antenna  40  ( FIG.  5   ) and may compensate for distributed capacitance CA ( FIG.  5   ) while concurrently helping to attach display cover layer  67  and thus display  14  to conductive sidewall  12 W. 
     The second end of conductive adhesive  82  at ledge  74  may have one or more openings such as openings (gaps)  84 . Additional adhesive such as adhesive  86  may be coupled to ledge  74  within openings  84 . Adhesive  86  may be, for example, pressure-sensitive adhesive that is activated by pressing display cover layer  67  ( FIG.  5   ) onto conductive sidewall  12 W and/or by heating. Adhesive  86  may adhere the display cover layer to ledge  74  more strongly than conductive adhesive  82 . In this way, forming openings  84  in conductive adhesive  82  and filling openings  84  with adhesive  86  may help to increase the strength with which the display cover layer is secured to conductive sidewall  12 W. 
       FIG.  7    is a perspective view of antenna  40  within interior cavity  68  of  FIG.  5   . In the example of  FIG.  7   , display  14  and conductive sidewall  12 W of  FIG.  5    have been omitted for the sake of clarity. As shown in  FIG.  7   , antenna  40  may be formed from conductive structures  102  layered onto an underlying antenna support structure such as dielectric substrate  88 . Dielectric substrate  88  may be formed from plastic, glass, ceramic, printed circuit board substrate, flexible printed circuit substrate, foam, or any other desired dielectric materials. Dielectric substrate  88  may be mounted to the interior surface of conductive rear housing wall  12 R. 
     Conductive structures  102  may include conductive traces, sheet metal, conductive foil, conductive tape, and/or other conductive structures that are layered over dielectric substrate  88 . A portion of conductive structures  102  may be formed on top surface  98  of dielectric substrate  88 . An additional portion of conductive structures  102  may also be formed on side surfaces  92 ,  94 , and/or  96  of dielectric substrate  88 . If desired, portions of conductive structures  102  may also be layered onto conductive rear housing wall  12 R. The portions of conductive structures  102  on conductive rear housing wall  12 R may be soldered, welded, or otherwise placed into electrical contact with conductive rear housing wall  12 R. The portions of conductive structures  102  on conductive rear housing wall  12 R may serve to couple resonating element arm  54  to ground. As just one example, conductive structures  102  may include a single piece of conductive tape that is layered over top surface  98 , that runs down sidewalls  92 ,  94 , and  96 , and that is folded onto conductive rear housing wall  12 R. As another example, the portion of conductive structures  102  on top surface  98  may be formed from conductive traces patterned onto top surface  98  whereas the remainder of conductive structures  102  is formed from conductive tape that couples the conductive traces to conductive rear housing wall  12 R (ground). These examples are merely illustrative. 
     Resonating element arm  54  of antenna  40  may be formed from the portion of conductive structures  102  on top surface  98  of dielectric substrate  88 . The return path for antenna  40  (e.g., return path  55  of  FIG.  3   ) may be formed the portion of conductive structures  102  on sidewalls  96 ,  94 , and/or  92  of dielectric substrate  88 . The amount of conductive material on sidewalls  96 ,  94 , and/or  92  may be selected so that the conductive material on sidewalls  96 ,  94 , and/or  92  exhibits the inductance of inductor  70  of  FIG.  5    (e.g., the portion of conductive structures  102  covering sidewalls  96 ,  94 , and/or  92  may form inductor  70  of  FIG.  5   ). The portions of dielectric substrate  88  that are not covered by conductive material (e.g., sidewall  90  and a portion of sidewall  92 ) may form a radiating aperture  108  for resonating element arm  54 . 
     Antenna  40  may be fed using any desired feed structures. For example, antenna  40  may be fed using a coaxial feed, conductive feed vias extending through dielectric substrate  88 , or any other desired feed structures. In the example of  FIG.  7   , antenna  40  is indirectly fed using monopole feed element  104 . As shown in  FIG.  7   , monopole feed element  104  may extend parallel to the width of tip  76  of resonating element arm  54 . Monopole feed element  104  may be coupled to signal conductor  48  of  FIG.  2   , for example. Antenna currents on monopole feed element  104  may excite corresponding antenna currents (e.g., in the frequency band of operation for antenna  40 ) on resonating element arm  54  via near-field electromagnetic (e.g., capacitive) coupling  106 . The antenna currents excited on resonating element arm  54  may radiate radio-frequency signals  78  of  FIG.  5   . Similarly, received radio-frequency signals  78  may produce antenna currents on resonating element arm  54 , which are then received by monopole feed element  104  via near-field electromagnetic coupling  106 . Monopole feed element  104  may exhibit a relatively narrow profile (parallel to the Y-axis of  FIG.  7   ) that allows monopole feed element  104  to fit within slot  64  ( FIG.  5   ) without requiring additional device volume to feed antenna  40 . 
     The example of  FIG.  7    is merely illustrative. Antenna  40  may be fed using any desired feed structures. Dielectric substrate  88  may have any desired shape having any desired number of planar and/or curved sides. Resonating element arm  54  may have any desired shape having any desired number of curved and/or straight edges. Conductive structures  102  may cover all of sidewall  92  and/or some of sidewall  90  of dielectric substrate  88  if desired. Conductive structures  102  may cover some, all, or none of sidewall  96  and/or some, all, or none of sidewall  94  if desired. 
       FIG.  8    is a cross-sectional side view of device  10  showing how a given antenna  40  may be formed within region  58  of device  10  (e.g., as taken along line BB′ of  FIG.  4   ). This is merely illustrative and, in another suitable arrangement, the antenna of  FIG.  8    may be located within region  60  of  FIG.  4    or elsewhere in device  10 . 
     As shown in  FIG.  8   , resonating element arm  54  for antenna  40  may be mounted within interior cavity  68  and may be coupled to conductive rear housing wall  12 R by inductor  70 . Inductor  70  may form the return path for antenna  40  and may have an inductance that compensates for detuning caused by the distributed capacitance between resonating element arm  54  and conductive rear housing wall  12 R (e.g., distributed capacitance CB of  FIG.  5   ). A device component such as device component  122  may be interposed between a portion of resonating element arm  54  and conductive rear housing wall  12 R (e.g., at tip  76 ). Device component  122  may include one of input-output devices  32  ( FIG.  2   ) or other components for device  10 . An example in which device component  122  is a speaker for device  10  is sometimes described herein as an example. In these scenarios, openings such as speaker port  124  may be formed in conductive sidewall  12 W. Speaker port  124  may allow sound emitted by device component  122  to pass to the exterior of device  10 . By co-locating device component  122  and antenna  40 , space consumption within device  10  may be minimized. 
     The example of  FIG.  8    shows a single grounding structure  66  coupled between conductive display structures  62  and conductive rear housing wall  12 R for the sake of clarity. In general, any desired number of grounding structures  66  may be coupled between conductive display structures  62  and conductive sidewall  12 W (e.g., across slot  64 ) and/or between conductive display structures  62  and conductive rear housing wall  12 R. Grounding structure  66  may include an inductor such as inductor  110 . Inductor  110  may have an inductance that is selected to compensate for detuning caused by the distributed capacitance between resonating element arm  54  and conductive display structures  62  (e.g., distributed capacitance CA of  FIG.  5   ). Inductor  110  may be formed from a discrete component, segments of conductive traces that exhibit a desired inductance, etc. Inductor  110  may include multiple discrete inductors coupled in series and/or in parallel if desired. 
     If care is not taken, the presence of device component  122  at tip  76  may undesirably limit the overall antenna efficiency and/or bandwidth for antenna  40 . In order to mitigate these effects, an inductive structure such as inductor  112  may be coupled between resonating element arm  54  and conductive rear housing wall  12 R. Inductor  112  may have a first terminal  114  coupled to resonating element arm  54  and a second terminal  116  coupled to conductive rear housing wall  12 R. First terminal  114  may be interposed on resonating element arm  54  between inductor  70  and tip  76  (e.g., between positive antenna feed terminal  44  and tip  76 ). Second terminal  116  may be interposed on conductive rear housing wall  12 R between inductor  70  and conductive sidewall  12 W (e.g., between ground antenna feed terminal  46  and conductive sidewall  12 W). Inductor  112  may be formed from a discrete inductor or from any other desired conductive structures (e.g., conductive traces, sheet metal, conductive foil, conductive tape, etc.). 
     Including an additional inductor such as inductor  112  in antenna  40  may establish multiple current loop paths on antenna  40 . For example, the antenna currents on antenna  40  (e.g., in the frequency band of operation for antenna  40 ) may follow a first current loop path  120  from positive antenna feed terminal  44 , through a portion of resonating element arm  54 , through inductor  70 , and through a portion of conductive rear housing wall  12 R to ground antenna feed terminal  46 . At the same time, the antenna currents on antenna  40  (e.g., in the frequency band of operation for antenna  40 ) may follow a second current loop path  118  from tip  76 , through a portion of resonating element arm  54 , through inductor  112 , and through a portion of conductive rear housing wall  12 R (e.g., around device component  122 ). The antenna current on current loop paths  120  and the antenna current on current loop path  118  may each contribute to the radiative response (resonance) of antenna  40  in the frequency band of operation for antenna  40 . Distributing the antenna current in this way may help the antenna currents to bypass device component  122 , thereby maximizing antenna efficiency and bandwidth for antenna  40  in conveying radio-frequency signals  78  through slot  64  and display cover layer  67 , despite the fact that antenna  40  is co-located with device component  122  within interior cavity  68 . 
       FIG.  9    is a perspective view of antenna  40  and device component  122  of  FIG.  8   . In the example of  FIG.  9   , display  14  and conductive sidewall  12 W of  FIG.  5    have been omitted for the sake of clarity. As shown in  FIG.  9   , dielectric substrate  88  may include a notch (e.g., at tip  76  of resonating element arm  54 ) such as notch  126  that accommodates device component  122 . Notch  126  may sometimes be referred to herein as opening  126 . Device component  122  may be mounted to conductive rear housing wall  12 R within notch  126 . 
     The portion of conductive structures  102  on top surface  98  of dielectric substrate  88  may form resonating element arm  54 . The portion(s) of conductive structures  102  on sidewalls  94 ,  92 , and/or  96  of dielectric substrate  88  may form the return path and inductor  70  ( FIG.  8   ) for antenna  40 . In the example of  FIG.  9   , conductive structures  102  only cover sidewall  94  whereas sidewalls  92 ,  96 , and  90  are free from conductive material. This is merely illustrative. The portion(s) of conductive structures  102  on conductive rear housing wall  12 R may be soldered, welded, or otherwise placed into electrical contact with conductive rear housing wall  12 R. The portions of conductive structures  102  on conductive rear housing wall  12 R may serve to couple resonating element arm  54  to ground. 
     As shown in  FIG.  9   , dielectric substrate  88  may have an additional sidewall  128  within notch  126  (e.g., notch  126  may have an open end at the side of device component  122  facing speaker port  124  of  FIG.  8    and may have an opposing closed end defined by additional sidewall  128  of dielectric substrate  88 ). A portion of conductive structures  102  may run down sidewall  128  to couple resonating element arm  54  to conductive rear housing wall  12 R within notch  126 . Antenna currents may flow from tip  76 , through the portion of conductive structures  102  on top surface  98 , and down the portion of conductive structures  102  on sidewall  128  to conductive rear housing wall  12 R (e.g., along current loop path  118 ). In this way, the portion of conductive structures  102  on sidewall  128  may form inductor  112  of  FIG.  8   . One or more discrete inductors may additionally or alternatively be used to form inductor  112  of  FIG.  8   . In other words, the portion of resonating element arm  54  extending from sidewall  128  (e.g., inductor  112  of  FIG.  8   ) to tip  76  may laterally surround or extend along two opposing sides of device component  122 . At the same time, antenna currents may flow down the portion of conductive structures  102  on sidewall  94  to conductive rear housing wall  12 R (e.g., along current loop path  120 ). Distributing the antenna current in this way may help the antenna currents to bypass device component  122  (e.g., within the frequency band of operation for antenna  40 ), thereby maximizing antenna efficiency and bandwidth for antenna  40  despite the fact that antenna  40  is co-located with device component  122 . 
     The example of  FIG.  9    is merely illustrative. Antenna  40  may be fed using any desired feed structures. Dielectric substrate  88  may have any desired shape having any desired number of planar and/or curved sides. Resonating element arm  54  may have any desired shape having any desired number of curved and/or straight edges. Conductive structures  102  may cover some or all of sidewall  94  and some or all of sidewall  128 . Conductive structures  102  may cover some or all of sidewalls  92 ,  96 , and/or  90 . Notch  126  may have any desired shape having any desired number of curved and/or straight sides (e.g., as defined by the form of device component  122  and dielectric substrate  88 ). 
     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: 20200616
Publication Date: 20231128
Grant Date: 20231128
Priority Date: 20200616
Inventors: HASNAT, FORHAD
Garrido Lopez, David
RAJAGOPALAN, HARISH
ASKARIAN AMIRI, MIKAL
GOMEZ ANGULO, RODNEY A.
ZHANG, LU
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q9/40", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q13/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/40", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q13/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q13/22", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 78825994