Electronic devices with display-overlapping antennas

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.

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.

DETAILED DESCRIPTION

An electronic device such as electronic device10ofFIG.1may be provided with wireless circuitry that includes antennas. The antennas may be used to transmit and/or receive wireless radio-frequency signals.

Electronic device10may be a portable electronic device or other suitable electronic device. For example, electronic device10may 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. Device10may 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.

Device10may include a housing such as housing12. Housing12, 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 housing12may be formed from dielectric or other low-conductivity material (e.g., glass, ceramic, plastic, sapphire, etc.). In other situations, housing12or at least some of the structures that make up housing12may be formed from metal elements.

Device10may, if desired, have a display such as display14. Display14may be mounted on the front face of device10. Display14may be a touch screen that incorporates capacitive touch electrodes or may be insensitive to touch. The rear face of housing12(i.e., the face of device10opposing the front face of device10) may have a substantially planar housing wall such as rear housing wall12R (e.g., a planar housing wall). Rear housing wall12R may have slots that pass entirely through the rear housing wall and that therefore separate portions of housing12from each other. Rear housing wall12R may include conductive portions and/or dielectric portions. If desired, rear housing wall12R may include a planar metal layer covered by a thin layer or coating of dielectric such as glass, plastic, sapphire, or ceramic. Housing12may also have shallow grooves that do not pass entirely through housing12. The slots and grooves may be filled with plastic or other dielectric. If desired, portions of housing12that 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).

Housing12may include peripheral housing structures such as peripheral structures12W. Peripheral structures12W and rear housing wall12R may sometimes be referred to herein collectively as conductive structures of housing12. Peripheral structures12W may run around the periphery of device10and display14. In configurations in which device10and display14have a rectangular shape with four edges, peripheral structures12W may be implemented using peripheral housing structures that have a rectangular ring shape with four corresponding edges and that extend from rear housing wall12R to the front face of device10(as an example). Peripheral structures12W or part of peripheral structures12W may serve as a bezel for display14(e.g., a cosmetic trim that surrounds all four sides of display14and/or that helps hold display14to device10) if desired. Peripheral structures12W may, if desired, form sidewall structures for device10(e.g., by forming a metal band with vertical sidewalls, curved sidewalls, etc.).

Peripheral structures12W 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 sidewalls12W 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 sidewalls12W.

It is not necessary for conductive sidewalls12W to have a uniform cross-section. For example, the top portion of conductive sidewalls12W may, if desired, have an inwardly protruding lip that helps hold display14in place. The bottom portion of conductive sidewalls12W may also have an enlarged lip (e.g., in the plane of the rear surface of device10). Conductive sidewalls12W 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 sidewalls12W serve as a bezel for display14), conductive sidewalls12W may run around the lip of housing12(i.e., conductive sidewalls12W may cover only the edge of housing12that surrounds display14and not the rest of the sidewalls of housing12).

If desired, rear housing wall12R may be formed from a metal such as stainless steel or aluminum and may sometimes be referred to herein as conductive rear housing wall12R or conductive rear wall12R. Conductive rear housing wall12R may lie in a plane that is parallel to display14. In configurations for device10in which the rear housing wall is formed from metal, it may be desirable to form parts of conductive sidewalls12W as integral portions of the housing structures forming the conductive rear housing wall of housing12. For example, conductive rear housing wall12R of device10may be formed from a planar metal structure and portions of conductive sidewalls12W on the sides of housing12may be formed as flat or curved vertically extending integral metal portions of the planar metal structure (e.g., housing structures12R and12W 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 housing12. Conductive rear housing wall12R may have one or more, two or more, or three or more portions. Conductive sidewalls12W and/or the conductive rear housing wall12R may form one or more exterior surfaces of device10(e.g., surfaces that are visible to a user of device10) and/or may be implemented using internal structures that do not form exterior surfaces of device10(e.g., conductive housing structures that are not visible to a user of device10such 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 device10and/or serve to hide structures12W and/or12R from view of the user).

Display14may have an array of pixels that form an active area AA that displays images for a user of device10. 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.

Display14may 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 housing12. To block these structures from view by a user of device10, the underside of the display cover layer or other layers in display14that 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.

Display14may 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 device10. In another suitable arrangement, the display cover layer may cover substantially all of the front face of device10or only a portion of the front face of device10. 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 port8or a microphone port. Speaker port8may be omitted if desired. Openings may be formed in housing12to 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.

Display14may 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. Housing12may 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 housing12(i.e., a substantially rectangular sheet formed from one or more metal parts that is welded or otherwise connected between opposing sides of conductive sidewalls12W). The backplate may form an exterior rear surface of device10or 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 device10and/or serve to hide the backplate from view of the user. Device10may 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 device10, may extend under active area AA of display14, for example.

At ends (regions)16and20, openings may be formed within the conductive structures of device10(e.g., between conductive sidewalls12W and opposing conductive ground structures such as conductive portions of conductive rear housing wall12R, conductive traces on a printed circuit board, conductive electrical components in display14, 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 device10, if desired.

Conductive housing structures and other conductive structures in device10may serve as a ground plane for the antennas in device10. The openings in ends20and16may 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 ends20and16. If desired, the ground plane that is under active area AA of display14and/or other metal structures in device10may have portions that extend into parts of the ends of device10(e.g., the ground may extend towards the dielectric-filled openings in ends20and16), thereby narrowing the slots in ends20and16.

In general, device10may include any suitable number of antennas (e.g., one or more, two or more, three or more, four or more, etc.). The antennas in device10may be located at opposing first and second ends of an elongated device housing (e.g., at ends20and16of device10ofFIG.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 ofFIG.1is merely illustrative.

Portions of conductive sidewalls12W may be provided with peripheral gap structures. For example, conductive sidewalls12W may be provided with one or more gaps such as gaps18, as shown inFIG.1. The gaps in conductive sidewalls12W may be filled with dielectric such as polymer, ceramic, glass, air, other dielectric materials, or combinations of these materials. Gaps18may divide conductive sidewalls12W into one or more peripheral conductive segments. There may be, for example, two peripheral conductive segments in conductive sidewalls12W (e.g., in an arrangement with two of gaps18), three peripheral conductive segments (e.g., in an arrangement with three of gaps18), four peripheral conductive segments (e.g., in an arrangement with four of gaps18), six peripheral conductive segments (e.g., in an arrangement with six gaps18), etc. The segments of conductive sidewalls12W that are formed in this way may form parts of antennas in device10.

If desired, openings in housing12such as grooves that extend partway or completely through housing12may extend across the width of the rear wall of housing12and may penetrate through the rear wall of housing12to divide the rear wall into different portions. These grooves may also extend into conductive sidewalls12W and may form antenna slots, gaps18, and other structures in device10. 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, device10may 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 end16of device10. A lower antenna may, for example, be formed at lower end20of device10. 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 device10may be used to support any communications bands of interest. For example, device10may 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 device10with 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 device10that is covered by active area AA of display14. Increasing the size of active area AA may reduce the size of inactive area IA within device10. This may reduce the area of ends20and16that is available for forming antennas within device10. 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 device10(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 device10is shown inFIG.2. As shown inFIG.2, device10may include control circuitry24. Control circuitry24may include storage such as storage circuitry28. Storage circuitry28may 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 circuitry24may include processing circuitry such as processing circuitry26. Processing circuitry26may be used to control the operation of device10. Processing circuitry26may 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 circuitry24may be configured to perform operations in device10using hardware (e.g., dedicated hardware or circuitry), firmware, and/or software. Software code for performing operations in device10may be stored on storage circuitry28(e.g., storage circuitry28may 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 circuitry28may be executed by processing circuitry26.

Control circuitry24may be used to run software on device10such 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 circuitry24may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry24include 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.

Device10may include input-output circuitry30. Input-output circuitry30may include input-output devices32. Input-output devices32may be used to allow data to be supplied to device10and to allow data to be provided from device10to external devices. Input-output devices32may include user interface devices, data port devices, and other input-output components. For example, input-output devices32may 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 device10using wired or wireless connections (e.g., some of input-output devices32may be peripherals that are coupled to a main processing unit or other portion of device10via a wired or wireless link).

Input-output circuitry30may include wireless circuitry34to support wireless communications. Wireless circuitry34may include radio-frequency (RF) transceiver circuitry36formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas such as antenna40, transmission lines such as transmission line38, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). While control circuitry24is shown separately from wireless circuitry34in the example ofFIG.1for the sake of clarity, wireless circuitry34may include processing circuitry that forms a part of processing circuitry26and/or storage circuitry that forms a part of storage circuitry28of control circuitry24(e.g., portions of control circuitry24may be implemented on wireless circuitry34). As an example, control circuitry24(e.g., processing circuitry26) may include baseband processor circuitry or other control components that form a part of wireless circuitry34.

Radio-frequency transceiver circuitry36may 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 circuitry36may 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 circuitry36may 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 circuitry36may 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 circuitry34may include one or more antennas such as antenna40. In general, radio-frequency transceiver circuitry36may be configured to cover (handle) any suitable communications (frequency) bands of interest. Radio-frequency transceiver circuitry36may convey radio-frequency signals using antennas40(e.g., antennas40may convey the radio-frequency signals for radio-frequency transceiver circuitry36). 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). Antennas40may 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). Antennas40may 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 antennas40each 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 inFIG.2, radio-frequency transceiver circuitry36may be coupled to antenna feed42of antenna40using transmission line38. Antenna feed42may include a positive antenna feed terminal such as positive antenna feed terminal44and may include a ground antenna feed terminal such as ground antenna feed terminal46. Transmission line38may be formed from metal traces on a printed circuit, cables, or other conductive structures. Transmission line38may have a positive transmission line signal path such as path48that is coupled to positive antenna feed terminal44. Transmission line38may have a ground transmission line signal path such as path50that is coupled to ground antenna feed terminal46. Path48may sometimes be referred to herein as signal conductor48and path50may sometimes be referred to herein as ground conductor50.

Transmission line paths such as transmission line38may be used to route antenna signals within device10(e.g., to convey radio-frequency signals between radio-frequency transceiver circuitry36and antenna feed42of antenna40). Transmission lines in device10may 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 device10such as transmission line38may be integrated into rigid and/or flexible printed circuit boards. In one suitable arrangement, transmission lines such as transmission line38may also include transmission line conductors (e.g., signal conductors48and ground conductors50) 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 line38and/or circuits such as these may be incorporated into antenna40(e.g., to support antenna tuning, to support operation in desired frequency bands, etc.). During operation, control circuitry24may use radio-frequency transceiver circuitry36and antenna(s)40to transmit and/or receive data wirelessly. Control circuitry24may, for example, receive wireless local area network communications wirelessly using radio-frequency transceiver circuitry36and antenna(s)40and may transmit wireless local area network communications wirelessly using radio-frequency transceiver circuitry36and antenna(s)40.

Antennas such as antenna40may be formed using any suitable antenna types. For example, antennas in device10may 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 antennas40to adjust antenna performance. If desired, antenna40may be provided with a conductive cavity that backs the antenna resonating element of antenna40(e.g., antenna40may 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 circuitry36. Alternatively, a given antenna40may 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 antennas40. Antennas that are implemented using planar inverted-F antenna structures may sometimes be referred to herein as planar inverted-F antennas.FIG.3is a schematic diagram of inverted-F antenna structures that may be used to form antenna40. As shown inFIG.3, antenna40may include an antenna resonating element such as antenna resonating element52and an antenna ground such as antenna ground56. Antenna resonating element52may include a resonating element arm54(sometimes referred to herein as antenna resonating element arm54, radiating arm54, radiating element arm54, or arm54) that is shorted to antenna ground56by return path55. Antenna40may be fed by coupling a transmission line (e.g., transmission line38ofFIG.3) to positive antenna feed terminal44and ground antenna feed terminal46of antenna feed42. Positive antenna feed terminal44may be coupled to resonating element arm54and ground antenna feed terminal46may be coupled to antenna ground56. Return path55may be coupled between resonating element arm54and antenna ground56in parallel with antenna feed42.

The length of resonating element arm54may determine the response (e.g., resonant) frequency of the antenna. For example, the length of resonating element arm54may 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 antenna40(e.g., where the effective wavelength is equal to a free space wavelength multiplied by a constant value associated with the dielectric material surrounding antenna40). In the example ofFIG.3, antenna40includes only a single resonating element arm54. This is merely illustrative. If desired, antenna40may 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 arm54may 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 ground56(e.g., resonating element arm54may have a width measured into and out of the plane of the page ofFIG.3), such that resonating element arm54forms a planar resonating element arm. In these scenarios, the inverted-F antenna structures ofFIG.3form planar inverted-F antenna structures.

FIG.4is a top-down view of device10showing different regions of device10that can be used to form antennas40. As shown inFIG.4, device10may include display14. Display14may 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 structures62ofFIG.4(e.g., conductive display structures62may form the display module for display14). The display cover layer of display14is omitted from the example ofFIG.4for the sake of clarity.

As shown inFIG.4, conductive display structures62may be separated from conductive sidewalls12W of device10by slots (gaps)64. Slots64may, for example, define inactive area IA of display14(FIG.1). Conductive display structures62may include a conductive frame for the active components of display14, 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 display14, and/or other conductive structures in display14. If desired, conductive display structures62may include portions of the pixel circuitry, touch sensor circuitry, force sensor circuitry, and/or other components in the display module for display14. Conductive display structures62may laterally extend across active area AA ofFIG.1, for example. As active area AA of display14is maximized, the space within device10occupied by the display module and conductive display structures62is also maximized, thereby limiting the amount of space available within device10for forming antennas40.

Antennas40(FIG.2) may be formed at upper end16of device10if desired. For example, device10may include a first antenna40within region58of upper end16and may include a second antenna40within region60of upper end16. Regions58and60(e.g., antennas40) may additionally or alternatively be located at lower end20or elsewhere on device10if desired. In general, device10may include any desired number of antennas40formed within any desired number of regions such as regions58and60, at any desired locations around the periphery of device10. Conductive sidewalls12W may be used in forming antenna ground56(FIG.3) for the antennas40within regions58and60.

In practice, larger antenna volumes allow for greater antenna efficiency bandwidth. At the same time, larger slots64may increase the aperture size for the antennas, thereby increasing the overall antenna efficiency in radiating through slots64and the front face of device10. As the size of active area AA (FIG.1) increases, the size of slots64and thus the volume (e.g., aperture size) of the antennas decreases. Conductive display structures62may overlap and/or may be in close proximity to the antennas within regions58and60. As the size of slots64is relatively small, the antennas located within regions58and60may have resonating element arms that at least partially overlap conductive display structures62.

However, if care is not taken, conductive display structures62overlapping the antenna resonating element arms may undesirably block some of the radio-frequency signals conveyed by the antennas, particularly through display14. This can reduce the efficiency and bandwidth of the antennas through the front face of device10. In order to mitigate these effects, conductive display structures62may be coupled to ground (e.g., antenna ground56ofFIG.32) at one or more locations overlapping each antenna (e.g., within regions58and60ofFIG.4).

Conductive grounding structures such as grounding structures66may be used to couple conductive display structures62to conductive sidewalls12W at one or more locations within regions58and60(e.g., overlapping each antenna aperture). Grounding structures66may have a first terminal coupled to conductive sidewalls12W and a second terminal coupled to conductive display structures62(e.g., grounding structures66may bridge slot64and may overlap the antenna aperture for a corresponding antenna40). This may couple the portion of conductive display structures62adjacent to each antenna aperture to a ground potential (e.g., antenna ground56ofFIG.3), thereby allowing radio-frequency signals for the antennas to pass through display14without being substantially blocked by conductive display structures62.

Grounding structures66may overlap any desired locations within the antennas40of regions58and60. In the example ofFIG.4, a single grounding structure66couples conductive display structures62to conductive sidewalls12W within region58whereas two grounding structures66couple different locations on conductive display structures62to conductive sidewalls12W within region60. This is merely illustrative. Regions58and60may include any desired number of grounding structures66. Grounding structures66may 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.5is a cross-sectional side view of device10showing how a given antenna40may be formed within region60of device10(e.g., as taken along line AA′ ofFIG.4). This is merely illustrative and, in another suitable arrangement, the antenna ofFIG.5may be located within region58ofFIG.4or elsewhere in device10. As shown inFIG.5, display14may include display cover layer67overlapping conductive display structures62(e.g., conductive display structures62may be mounted to the inner surface of display cover layer67). Display cover layer67may be transparent and may be formed from any desired materials such as glass, plastic, or sapphire. Portions of display cover layer67may be provided with an opaque masking layer such as an ink layer if desired.

Display14may be mounted to conductive sidewalls12W, one of which is illustrated inFIG.5. Conductive sidewall12W may have an inwardly-protruding portion (extension)74that is sometimes referred to herein as ledge74or datum74. Ledge74may have a lateral surface that extends parallel to the inner surface of display cover layer67. Display14may be secured to conductive sidewall12W by coupling display cover layer67to ledge74using adhesive material.

Conductive display structures62may be separated from conductive rear housing wall12R by interior cavity68. Interior cavity68may be a conductive cavity having (conductive) edges defined by the conductive material in conductive rear housing wall12R and conductive display structures62. The lateral periphery of conductive display structures62may be separated from conductive sidewall12W by a corresponding slot64(e.g., inactive area IA ofFIG.1). The antenna resonating element52for antenna40may be mounted within interior cavity68(e.g., resonating element arm54may be located within interior cavity68).

Antenna feed42may be coupled between resonating element arm54and conductive rear housing wall12R (e.g., across a portion of interior cavity68). Positive antenna feed terminal44may be coupled to resonating element arm54whereas ground antenna feed terminal46is coupled to conductive rear housing wall12R. Conductive rear housing wall12R and conductive sidewall12W may form the antenna ground for antenna40(e.g., antenna ground56ofFIG.3). An inductor such as inductor70may couple an end of resonating element arm54to ground (e.g., conductive rear housing wall12R). Inductor70may form a return path for antenna resonating element52(e.g., return path55ofFIG.3). Resonating element arm54may extend from inductor70to an opposing tip76. Antenna feed42may be coupled to resonating element arm54between tip76and inductor70. Resonating element arm54may completely or partially overlap conductive display structures62such that some or all of antenna resonating element52is interposed within interior cavity68between conductive display structures62and conductive rear housing wall12R (e.g., tip76may overlap conductive display structures62or may overlap slot64).

If care is not taken, the presence of conductive display structures62may block antenna40from radiating through the front face of device10, thereby limiting the overall antenna efficiency for antenna40through the front face of device10. However, the presence of slot64may allow antenna40to convey radio-frequency signals78between interior cavity68and the free space exterior to device10(e.g., antenna40may transmit and/or receive radio-frequency signals78through slot64and display cover layer67). If desired, interior cavity68may form a conductive cavity-back for antenna40that helps to optimize the radiation pattern and efficiency for antenna40.

Resonating element arm54may extend across a lateral area that lies within the X-Y plane ofFIG.5(e.g., resonating element arm54may be a planar inverted-F antenna resonating element arm). In practice, the lateral area of resonating element arm54may extend parallel to the bottom surface of conductive display structures62. This may form a distributed capacitance such as distributed capacitance CA between resonating element arm54and conductive display structures62. At the same time, an additional distributed capacitance CB may be present between resonating element arm54and conductive rear housing wall12R. If care is not taken, distributed capacitance CA and/or distributed capacitance CB may undesirably detune the frequency response of antenna40(e.g., away from the frequency band of operation for antenna40).

In order to mitigate the effects of distributed capacitance CA on the frequency response of antenna40, an inductor such as inductor72may be coupled between conductive display structures62and conductive sidewall12W. In this way, inductor72may be used to form a corresponding grounding structure66for antenna40. The inductance of inductor72may be selected to cancel out the effects of distributed capacitance CA on antenna40. Similarly, the inductance of inductor70may be selected to mitigate the effects of distributed capacitance CB on the frequency response of antenna40. Inductors70and72may be formed from discrete components (e.g., discrete inductors such as surface mount inductors), segments of conductive material that exhibit a desired inductance, etc. Inductors70and/or72may include multiple inductors coupled in series and/or in parallel if desired. By compensating for the effects of distributed capacitances CA and CB, antenna40may convey radio-frequency signals78through slot64and display cover layer67with satisfactory antenna efficiency across the entire frequency band of operation for antenna40.

Grounding structure66may be coupled to ledge74of conductive sidewall12W if desired.FIG.6is a top down view showing how grounding structure66may be coupled to ledge74(e.g., taken in the direction of arrow80ofFIG.5). Display cover layer67ofFIG.5has been omitted fromFIG.6for the sake of clarity.

As shown inFIG.6, grounding structure66may include one or more strips of conductive adhesive82. Conductive adhesive82may be, for example, conductive tape having one or two adhesive sides (surfaces). Conductive adhesive82may have a first end coupled to conductive display structures62(FIG.5) and an opposing second end coupled to ledge74of conductive sidewall12W. If desired, the first end of conductive adhesive82may be coupled to a terminal of inductor72(FIG.5). In another suitable arrangement, conductive adhesive82may exhibit an inductance that is selected so that conductive adhesive82itself forms inductor72ofFIG.5. Conductive adhesive82(e.g., grounding structure66) may form a conductive path to ground from conductive display structures62(FIG.5). The second end of conductive adhesive82may help to secure (adhere) display cover layer67(FIG.5) to conductive sidewall12W. In this way, grounding structure66may optimize antenna efficiency and bandwidth through slot64for antenna40(FIG.5) and may compensate for distributed capacitance CA (FIG.5) while concurrently helping to attach display cover layer67and thus display14to conductive sidewall12W.

The second end of conductive adhesive82at ledge74may have one or more openings such as openings (gaps)84. Additional adhesive such as adhesive86may be coupled to ledge74within openings84. Adhesive86may be, for example, pressure-sensitive adhesive that is activated by pressing display cover layer67(FIG.5) onto conductive sidewall12W and/or by heating. Adhesive86may adhere the display cover layer to ledge74more strongly than conductive adhesive82. In this way, forming openings84in conductive adhesive82and filling openings84with adhesive86may help to increase the strength with which the display cover layer is secured to conductive sidewall12W.

FIG.7is a perspective view of antenna40within interior cavity68ofFIG.5. In the example ofFIG.7, display14and conductive sidewall12W ofFIG.5have been omitted for the sake of clarity. As shown inFIG.7, antenna40may be formed from conductive structures102layered onto an underlying antenna support structure such as dielectric substrate88. Dielectric substrate88may be formed from plastic, glass, ceramic, printed circuit board substrate, flexible printed circuit substrate, foam, or any other desired dielectric materials. Dielectric substrate88may be mounted to the interior surface of conductive rear housing wall12R.

Conductive structures102may include conductive traces, sheet metal, conductive foil, conductive tape, and/or other conductive structures that are layered over dielectric substrate88. A portion of conductive structures102may be formed on top surface98of dielectric substrate88. An additional portion of conductive structures102may also be formed on side surfaces92,94, and/or96of dielectric substrate88. If desired, portions of conductive structures102may also be layered onto conductive rear housing wall12R. The portions of conductive structures102on conductive rear housing wall12R may be soldered, welded, or otherwise placed into electrical contact with conductive rear housing wall12R. The portions of conductive structures102on conductive rear housing wall12R may serve to couple resonating element arm54to ground. As just one example, conductive structures102may include a single piece of conductive tape that is layered over top surface98, that runs down sidewalls92,94, and96, and that is folded onto conductive rear housing wall12R. As another example, the portion of conductive structures102on top surface98may be formed from conductive traces patterned onto top surface98whereas the remainder of conductive structures102is formed from conductive tape that couples the conductive traces to conductive rear housing wall12R (ground). These examples are merely illustrative.

Resonating element arm54of antenna40may be formed from the portion of conductive structures102on top surface98of dielectric substrate88. The return path for antenna40(e.g., return path55ofFIG.3) may be formed the portion of conductive structures102on sidewalls96,94, and/or92of dielectric substrate88. The amount of conductive material on sidewalls96,94, and/or92may be selected so that the conductive material on sidewalls96,94, and/or92exhibits the inductance of inductor70ofFIG.5(e.g., the portion of conductive structures102covering sidewalls96,94, and/or92may form inductor70ofFIG.5). The portions of dielectric substrate88that are not covered by conductive material (e.g., sidewall90and a portion of sidewall92) may form a radiating aperture108for resonating element arm54.

Antenna40may be fed using any desired feed structures. For example, antenna40may be fed using a coaxial feed, conductive feed vias extending through dielectric substrate88, or any other desired feed structures. In the example ofFIG.7, antenna40is indirectly fed using monopole feed element104. As shown inFIG.7, monopole feed element104may extend parallel to the width of tip76of resonating element arm54. Monopole feed element104may be coupled to signal conductor48ofFIG.2, for example. Antenna currents on monopole feed element104may excite corresponding antenna currents (e.g., in the frequency band of operation for antenna40) on resonating element arm54via near-field electromagnetic (e.g., capacitive) coupling106. The antenna currents excited on resonating element arm54may radiate radio-frequency signals78ofFIG.5. Similarly, received radio-frequency signals78may produce antenna currents on resonating element arm54, which are then received by monopole feed element104via near-field electromagnetic coupling106. Monopole feed element104may exhibit a relatively narrow profile (parallel to the Y-axis ofFIG.7) that allows monopole feed element104to fit within slot64(FIG.5) without requiring additional device volume to feed antenna40.

The example ofFIG.7is merely illustrative. Antenna40may be fed using any desired feed structures. Dielectric substrate88may have any desired shape having any desired number of planar and/or curved sides. Resonating element arm54may have any desired shape having any desired number of curved and/or straight edges. Conductive structures102may cover all of sidewall92and/or some of sidewall90of dielectric substrate88if desired. Conductive structures102may cover some, all, or none of sidewall96and/or some, all, or none of sidewall94if desired.

FIG.8is a cross-sectional side view of device10showing how a given antenna40may be formed within region58of device10(e.g., as taken along line BB′ ofFIG.4). This is merely illustrative and, in another suitable arrangement, the antenna ofFIG.8may be located within region60ofFIG.4or elsewhere in device10.

As shown inFIG.8, resonating element arm54for antenna40may be mounted within interior cavity68and may be coupled to conductive rear housing wall12R by inductor70. Inductor70may form the return path for antenna40and may have an inductance that compensates for detuning caused by the distributed capacitance between resonating element arm54and conductive rear housing wall12R (e.g., distributed capacitance CB ofFIG.5). A device component such as device component122may be interposed between a portion of resonating element arm54and conductive rear housing wall12R (e.g., at tip76). Device component122may include one of input-output devices32(FIG.2) or other components for device10. An example in which device component122is a speaker for device10is sometimes described herein as an example. In these scenarios, openings such as speaker port124may be formed in conductive sidewall12W. Speaker port124may allow sound emitted by device component122to pass to the exterior of device10. By co-locating device component122and antenna40, space consumption within device10may be minimized.

The example ofFIG.8shows a single grounding structure66coupled between conductive display structures62and conductive rear housing wall12R for the sake of clarity. In general, any desired number of grounding structures66may be coupled between conductive display structures62and conductive sidewall12W (e.g., across slot64) and/or between conductive display structures62and conductive rear housing wall12R. Grounding structure66may include an inductor such as inductor110. Inductor110may have an inductance that is selected to compensate for detuning caused by the distributed capacitance between resonating element arm54and conductive display structures62(e.g., distributed capacitance CA ofFIG.5). Inductor110may be formed from a discrete component, segments of conductive traces that exhibit a desired inductance, etc. Inductor110may include multiple discrete inductors coupled in series and/or in parallel if desired.

If care is not taken, the presence of device component122at tip76may undesirably limit the overall antenna efficiency and/or bandwidth for antenna40. In order to mitigate these effects, an inductive structure such as inductor112may be coupled between resonating element arm54and conductive rear housing wall12R. Inductor112may have a first terminal114coupled to resonating element arm54and a second terminal116coupled to conductive rear housing wall12R. First terminal114may be interposed on resonating element arm54between inductor70and tip76(e.g., between positive antenna feed terminal44and tip76). Second terminal116may be interposed on conductive rear housing wall12R between inductor70and conductive sidewall12W (e.g., between ground antenna feed terminal46and conductive sidewall12W). Inductor112may 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 inductor112in antenna40may establish multiple current loop paths on antenna40. For example, the antenna currents on antenna40(e.g., in the frequency band of operation for antenna40) may follow a first current loop path120from positive antenna feed terminal44, through a portion of resonating element arm54, through inductor70, and through a portion of conductive rear housing wall12R to ground antenna feed terminal46. At the same time, the antenna currents on antenna40(e.g., in the frequency band of operation for antenna40) may follow a second current loop path118from tip76, through a portion of resonating element arm54, through inductor112, and through a portion of conductive rear housing wall12R (e.g., around device component122). The antenna current on current loop paths120and the antenna current on current loop path118may each contribute to the radiative response (resonance) of antenna40in the frequency band of operation for antenna40. Distributing the antenna current in this way may help the antenna currents to bypass device component122, thereby maximizing antenna efficiency and bandwidth for antenna40in conveying radio-frequency signals78through slot64and display cover layer67, despite the fact that antenna40is co-located with device component122within interior cavity68.

FIG.9is a perspective view of antenna40and device component122ofFIG.8. In the example ofFIG.9, display14and conductive sidewall12W ofFIG.5have been omitted for the sake of clarity. As shown inFIG.9, dielectric substrate88may include a notch (e.g., at tip76of resonating element arm54) such as notch126that accommodates device component122. Notch126may sometimes be referred to herein as opening126. Device component122may be mounted to conductive rear housing wall12R within notch126.

The portion of conductive structures102on top surface98of dielectric substrate88may form resonating element arm54. The portion(s) of conductive structures102on sidewalls94,92, and/or96of dielectric substrate88may form the return path and inductor70(FIG.8) for antenna40. In the example ofFIG.9, conductive structures102only cover sidewall94whereas sidewalls92,96, and90are free from conductive material. This is merely illustrative. The portion(s) of conductive structures102on conductive rear housing wall12R may be soldered, welded, or otherwise placed into electrical contact with conductive rear housing wall12R. The portions of conductive structures102on conductive rear housing wall12R may serve to couple resonating element arm54to ground.

As shown inFIG.9, dielectric substrate88may have an additional sidewall128within notch126(e.g., notch126may have an open end at the side of device component122facing speaker port124ofFIG.8and may have an opposing closed end defined by additional sidewall128of dielectric substrate88). A portion of conductive structures102may run down sidewall128to couple resonating element arm54to conductive rear housing wall12R within notch126. Antenna currents may flow from tip76, through the portion of conductive structures102on top surface98, and down the portion of conductive structures102on sidewall128to conductive rear housing wall12R (e.g., along current loop path118). In this way, the portion of conductive structures102on sidewall128may form inductor112ofFIG.8. One or more discrete inductors may additionally or alternatively be used to form inductor112ofFIG.8. In other words, the portion of resonating element arm54extending from sidewall128(e.g., inductor112ofFIG.8) to tip76may laterally surround or extend along two opposing sides of device component122. At the same time, antenna currents may flow down the portion of conductive structures102on sidewall94to conductive rear housing wall12R (e.g., along current loop path120). Distributing the antenna current in this way may help the antenna currents to bypass device component122(e.g., within the frequency band of operation for antenna40), thereby maximizing antenna efficiency and bandwidth for antenna40despite the fact that antenna40is co-located with device component122.

The example ofFIG.9is merely illustrative. Antenna40may be fed using any desired feed structures. Dielectric substrate88may have any desired shape having any desired number of planar and/or curved sides. Resonating element arm54may have any desired shape having any desired number of curved and/or straight edges. Conductive structures102may cover some or all of sidewall94and some or all of sidewall128. Conductive structures102may cover some or all of sidewalls92,96, and/or90. Notch126may have any desired shape having any desired number of curved and/or straight sides (e.g., as defined by the form of device component122and dielectric substrate88).