PATENT DOCUMENT

Publication Number: US-12062858-B2
Application Number: US-202217849501-A
Country: US
Kind Code: B2

Title: Electronic device with switchable antenna loop path

Abstract:
An electronic device may be provided with peripheral conductive housing structures having first and second segments. The device may include an antenna having a resonating arm formed from the first segment, an antenna ground, and a tuning element. The tuning element may have first, second, and third terminals. The first terminal may be coupled to the second segment. The antenna may have a switchable loop path that includes a first path from the second terminal to the first segment, a second path from first segment to a first point on the antenna ground, a portion of the antenna ground from the first point to a second point, and a third path from the second point to the third terminal. The tuning element may selectively activate the switchable loop path to boost performance of the antenna in a frequency band between 3300 MHz and 5000 MHz when needed.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 ground structures; 
 peripheral conductive housing structures having a first segment and a second segment separated from the first segment by a dielectric-filled gap, the first and second segments being separated from the ground structures by a slot; 
 an antenna feed terminal on the first segment; 
 a tuning element having a first terminal coupled to the second segment and having a second terminal and a third terminal; 
 a first conductive path that couples the second terminal to a first point on the first segment across the dielectric-filled gap; 
 a second conductive path that couples the first point to a second point on the ground structures across the slot; and 
 a third conductive path that couples the third terminal to a third point on the ground structures across the slot, the third point being separate from the second point. 
 
     
     
       2. The electronic device of  claim 1 , further comprising:
 a flexible printed circuit that runs along the second segment, the tuning element being mounted to the flexible printed circuit. 
 
     
     
       3. The electronic device of  claim 2 , further comprising conductive traces on the flexible printed circuit and coupled to the tuning element. 
     
     
       4. The electronic device of  claim 1 , wherein the tuning element comprises a single-pole three-throw (SP3T) switch. 
     
     
       5. The electronic device of  claim 1 , wherein the tuning element has a first state in which the first terminal is coupled to the third terminal. 
     
     
       6. The electronic device of  claim 5 , wherein the tuning element has a second state in which the first terminal is decoupled from the third terminal. 
     
     
       7. The electronic device of  claim 1 , wherein the slot has an extended portion extending beyond the dielectric-filled gap, the third conductive path being coupled across the extended portion of the slot. 
     
     
       8. The electronic device of  claim 1 , wherein antenna currents flowing through the first conductive path, the second conductive path, a portion of the ground structures extending between the second and third points, and from the third terminal to the first terminal are configured to radiate radio-frequency signals at a frequency between 3300 MHz and 5000 MHz. 
     
     
       9. The electronic device of  claim 1 , further comprising:
 a display mounted to the peripheral conductive housing structures and having conductive display structures; 
 a rear housing wall opposite the display and having a conductive support plate; 
 a mid-chassis between the display and the conductive support plate; and 
 conductive interconnect structures that couple the conductive display structures to the mid-chassis and that couple the mid-chassis to the conductive support plate, wherein the ground structures comprise the conductive display structures, the conductive support plate, the mid-chassis, and the conductive interconnect structures. 
 
     
     
       10. An electronic device comprising:
 peripheral conductive housing structures having a dielectric-filled gap that divides the peripheral conductive housing structures into a first segment and a second segment; and 
 an antenna having
 an antenna ground separated from the first and second segments by a slot, 
 a resonating element arm formed from the first segment, and 
 a switchable loop path that includes a first conductive path coupled across the dielectric-filled gap, a second conductive path coupled across the slot, a third conductive path coupled across the slot, and a portion of the antenna ground extending from the second conductive path to the third conductive path. 
 
 
     
     
       11. The electronic device of  claim 10 , wherein the second conductive path is coupled between the first segment and the antenna ground and the third conductive path is coupled between the second segment and the antenna ground. 
     
     
       12. The electronic device of  claim 11 , wherein the first conductive path is coupled to a first point on the first segment, the second conductive path is coupled between the first point and a second point on the antenna ground, and the third conductive path is coupled between the second segment and a third point on the antenna ground. 
     
     
       13. The electronic device of  claim 10 , further comprising:
 a switchable component having a first terminal coupled to the second segment, a second terminal coupled to the first conductive path, and a third terminal coupled to the third conductive path. 
 
     
     
       14. The electronic device of  claim 13 , wherein the switchable component has a first state and a second state, the switchable loop path contributing more to a radiative response of the antenna in the first state than in the second state. 
     
     
       15. The electronic device of  claim 13 , further comprising:
 a printed circuit running along the second segment, wherein the switchable component is surface-mounted to the printed circuit. 
 
     
     
       16. The electronic device of  claim 13 , wherein the switchable loop path extends from the third terminal to the second segment through the first terminal. 
     
     
       17. An antenna comprising:
 an antenna ground; 
 a resonating element arm; 
 a feed terminal coupled to the resonating element arm; 
 a conductive structure separated from the resonating element arm by a gap; 
 a tuning element having a first terminal, a second terminal, and a third terminal, the first terminal being coupled to the conductive structure; 
 a first conductive path that couples the first terminal to the resonating element arm; 
 a second conductive path that couples the resonating element arm to the antenna ground; and 
 a third conductive path that couples the antenna ground to the third terminal. 
 
     
     
       18. The antenna of  claim 17 , wherein the second conductive path is coupled to a first point on the antenna ground and the third conductive path is coupled to a second point on the antenna ground that is separated from the first point. 
     
     
       19. The antenna of  claim 17 , wherein the first conductive path is coupled to a point on the resonating element arm and the second conductive path is coupled to the point on the resonating element arm. 
     
     
       20. The antenna of  claim 17 , wherein the tuning element comprises a single-pole three-throw (SP3T) switch.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications capabilities. 
     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 and with satisfactory efficiency bandwidth. 
     SUMMARY 
     An electronic device may be provided with wireless circuitry and a housing having peripheral conductive housing structures. A dielectric gap may divide the peripheral conductive housing structures into first and second segments. The first and second segments may be separated from an antenna ground by a slot. 
     The wireless circuitry may include an antenna. The antenna may have a resonating element arm formed from the first segment. The antenna may have a tuning element. The tuning element may have first, second, and third terminals. The first terminal may be coupled to the second segment. The antenna may have a switchable loop path. The switchable loop path may include a first conductive path extending from the second terminal to a first point on the first segment across the gap. The switchable loop path may include a second conductive path extending from the first point to a second point on the antenna ground across the slot. The switchable loop path may include a portion of the antenna ground extending from the second point to a third point on the antenna ground. The switchable loop path may include a third conductive path extending from the third point to the third terminal across the slot. The switchable loop path may extend from the third terminal to the second segment through the first terminal. The tuning element may be controlled to selectively activate the switchable loop path to boost performance of the antenna in a frequency band between 3300 MHz and 5000 MHz. 
    
    
     
       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 wireless circuitry in accordance with some embodiments. 
         FIG.  4    is a cross-sectional side view of an electronic device having housing structures that may be used in forming antenna structures in accordance with some embodiments. 
         FIG.  5    is a top interior view of the lower end of an illustrative electronic device having peripheral conductive housing structures with dielectric gaps for forming one or more antenna resonating elements in accordance with some embodiments. 
         FIG.  6    is a rear interior view of the lower end of an illustrative electronic device having an antenna with a switchable loop path in accordance with some embodiments. 
         FIG.  7    is a plot showing how an illustrative antenna of the type shown in  FIG.  6    may use a switchable loop path to optimize performance in a given frequency band 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. 
     Device  10  may be a portable electronic device or other suitable electronic device. For example, 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, headset 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, a 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 (e.g., a dielectric cover layer). 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 materials. 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. Conductive portions of peripheral structures  12 W and conductive portions of 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). In other words, device  10  may have a length (e.g., measured parallel to the Y-axis), a width that is less than the length (e.g., measured parallel to the X-axis), and a height (e.g., measured parallel to the Z-axis) that is less than the width. 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 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). Peripheral conductive housing structures  12 W may be formed from a metal such as stainless steel, aluminum, alloys, or other suitable materials. One, two, or more than two separate structures may be used in forming peripheral conductive housing structures  12 W. 
     It is not necessary for peripheral conductive housing structures  12 W to have a uniform cross-section. For example, the top portion of peripheral conductive housing structures  12 W may, if desired, have an inwardly protruding ledge that helps hold display  14  in place. The bottom portion of peripheral conductive housing structures  12 W may also have an enlarged lip (e.g., in the plane of the rear surface of device  10 ). Peripheral conductive housing structures  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 peripheral conductive housing structures  12 W serve as a bezel for display  14 ), peripheral conductive housing structures  12 W may run around the lip of housing  12  (i.e., peripheral conductive housing structures  12 W may cover only the edge of housing  12  that surrounds display  14  and not the rest of the sidewalls of housing  12 ). 
     Rear housing wall  12 R may lie in a plane that is parallel to display  14 . In configurations for device  10  in which some or all of rear housing wall  12 R is formed from metal, it may be desirable to form parts of peripheral conductive housing structures  12 W as integral portions of the housing structures forming rear housing wall  12 R. For example, rear housing wall  12 R of device  10  may include a planar metal structure and portions of peripheral conductive housing structures  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 . Rear housing wall  12 R may have one or more, two or more, or three or more portions. Peripheral conductive housing structures  12 W and/or conductive portions of 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/cover 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 peripheral conductive housing structures  12 W and/or conductive portions of rear housing wall  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 of display  14  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. Inactive area IA may include a recessed region such as notch  24  that extends into active area AA. Active area AA may, for example, be defined by the lateral area of a display module for display  14  (e.g., a display module that includes pixel circuitry, touch sensor circuitry, etc.). The display module may have a recess or notch in upper region  20  of device  10  that is free from active display circuitry (i.e., that forms notch  24  of inactive area IA). Notch  24  may be a substantially rectangular region that is surrounded (defined) on three sides by active area AA and on a fourth side by peripheral conductive housing structures  12 W. 
     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  16  in notch  24  or a microphone port. 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 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 conductive support plate or backplate) that spans the walls of housing  12  (e.g., a substantially rectangular sheet formed from one or more metal parts that is welded or otherwise connected between opposing sides of peripheral conductive housing structures  12 W). The conductive support plate may form an exterior rear surface of device  10  or may be covered by a dielectric cover layer such as a thin cosmetic layer, protective coating, 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 conductive support plate from view of the user (e.g., the conductive support plate may form part of rear housing wall  12 R). 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. 
     In regions  22  and  20 , openings may be formed within the conductive structures of device  10  (e.g., between peripheral conductive housing structures  12 W and opposing conductive ground structures such as conductive portions of 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 regions  22  and  20  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 regions  22  and  20 . 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 regions  22  and  20 ), thereby narrowing the slots in regions  22  and  20 . Region  22  may sometimes be referred to herein as lower region  22  or lower end  22  of device  10 . Region  20  may sometimes be referred to herein as upper region  20  or upper end  20  of device  10 . 
     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 lower region  22  and/or upper region  20  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 peripheral conductive housing structures  12 W may be provided with peripheral gap structures. For example, peripheral conductive housing structures  12 W may be provided with one or more dielectric-filled gaps such as gaps  18 , as shown in  FIG.  1   . The gaps in peripheral conductive housing structures  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 peripheral conductive housing structures  12 W into one or more peripheral conductive segments. The conductive segments that are formed in this way may form parts of antennas in device  10  if desired. Other dielectric openings may be formed in peripheral conductive housing structures  12 W (e.g., dielectric openings other than gaps  18 ) and may serve as dielectric antenna windows for antennas mounted within the interior of device  10 . Antennas within device  10  may be aligned with the dielectric antenna windows for conveying radio-frequency signals through peripheral conductive housing structures  12 W. Antennas within device  10  may also be aligned with inactive area IA of display  14  for conveying radio-frequency signals through display  14 . 
     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 behind display  14  that is available for antennas within device  10 . For example, active area AA of display  14  may include conductive structures that serve to block radio-frequency signals handled by antennas mounted behind active area AA from radiating through the front face of device  10 . 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 communicate with wireless equipment external to device  10  with satisfactory efficiency bandwidth. 
     In a typical scenario, device  10  may have one or more upper antennas and one or more lower antennas. An upper antenna may, for example, be formed in upper region  20  of device  10 . A lower antenna may, for example, be formed in lower region  22  of device  10 . Additional antennas may be formed along the edges of housing  12  extending between regions  20  and  22  if desired. 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. Other antennas for covering any other desired frequencies may also be mounted at any desired locations within the interior of device  10 . The example of  FIG.  1    is merely illustrative. If desired, housing  12  may have other shapes (e.g., a square shape, cylindrical shape, spherical shape, combinations of these and/or different shapes, etc.). 
     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  38 . Control circuitry  38  may include storage such as storage circuitry  30 . Storage circuitry  30  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  38  may include processing circuitry such as processing circuitry  32 . Processing circuitry  32  may be used to control the operation of device  10 . Processing circuitry  32  may include on one or more microprocessors, microcontrollers, digital signal processors, host processors, baseband processor integrated circuits, application specific integrated circuits, graphics processing units, central processing units (CPUs), etc. Control circuitry  38  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  30  (e.g., storage circuitry  30  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  30  may be executed by processing circuitry  32 . 
     Control circuitry  38  may be used to run software on device  10  such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, control circuitry  38  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  38  include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol or other WPAN protocols, IEEE 802.11ad protocols, cellular telephone protocols, MIMO protocols, antenna diversity protocols, satellite navigation system protocols, antenna-based spatial ranging protocols (e.g., radio detection and ranging (RADAR) protocols or other desired range detection protocols for signals conveyed at millimeter and centimeter wave frequencies), etc. Each communication 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  26 . Input-output circuitry  26  may include input-output devices  28 . Input-output devices  28  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  28  may include user interface devices, data port devices, sensors, and other input-output components. For example, input-output devices may include touch screens, displays without touch sensor capabilities, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, gyroscopes, accelerometers or other components that can detect motion and device orientation relative to the Earth, capacitance sensors, proximity sensors (e.g., a capacitive proximity sensor and/or an infrared proximity sensor), magnetic sensors, and other sensors and input-output components. 
     Input-output circuitry  26  may include wireless circuitry such as wireless circuitry  34  for wirelessly conveying radio-frequency signals. While control circuitry  38  is shown separately from wireless circuitry  34  in the example of  FIG.  2    for the sake of clarity, wireless circuitry  34  may include processing circuitry that forms a part of processing circuitry  32  and/or storage circuitry that forms a part of storage circuitry  30  of control circuitry  38  (e.g., portions of control circuitry  38  may be implemented on wireless circuitry  34 ). As an example, control circuitry  38  may include baseband processor circuitry or other control components that form a part of wireless circuitry  34 . 
     Wireless circuitry  34  may include radio-frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas, transmission lines, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Wireless circuitry  34  may include radio-frequency transceiver circuitry  36  for handling transmission and/or reception of radio-frequency signals within corresponding frequency bands at radio frequencies (sometimes referred to herein as communications bands or simply as “bands”). The frequency bands handled by radio-frequency transceiver circuitry  36  may include wireless local area network (WLAN) frequency bands (e.g., Wi-Fi® (IEEE 802.11) or other WLAN communications bands) such as a 2.4 GHz WLAN band (e.g., from 2400 to 2480 MHz), a 5 GHz WLAN band (e.g., from 5180 to 5825 MHz), a Wi-Fi® 6E band (e.g., from 5925-7125 MHz), and/or other Wi-Fi® bands (e.g., from 1875-5160 MHz), wireless personal area network (WPAN) frequency bands such as the 2.4 GHz Bluetooth® band or other WPAN communications bands, cellular telephone communications bands such as a cellular low band (LB) (e.g., 600 to 960 MHz), a cellular low-midband (LMB) (e.g., 1400 to 1550 MHz), a cellular midband (MB) (e.g., from 1700 to 2200 MHz), a cellular high band (HB) (e.g., from 2300 to 2700 MHz), a cellular ultra-high band (UHB) (e.g., from 3300 to 5000 MHz, or other cellular communications bands between about 600 MHz and about 5000 MHz), 3G bands, 4G LTE bands, 3GPP 5G New Radio Frequency Range 1 (FR1) bands below 10 GHz, 3GPP 5G New Radio (NR) Frequency Range 2 (FR2) bands between 20 and 60 GHz, other centimeter or millimeter wave frequency bands between 10-300 GHz, near-field communications frequency bands (e.g., at 13.56 MHz), satellite navigation frequency bands such as the Global Positioning System (GPS) L1 band (e.g., at 1575 MHz), L2 band (e.g., at 1228 MHz), L3 band (e.g., at 1381 MHz), L4 band (e.g., at 1380 MHz), and/or L5 band (e.g., at 1176 MHz), a Global Navigation Satellite System (GLONASS) band, a BeiDou Navigation Satellite System (BDS) band, ultra-wideband (UWB) frequency bands that operate under the IEEE 802.15.4 protocol and/or other ultra-wideband communications protocols (e.g., a first UWB communications band at 6.5 GHz and/or a second UWB communications band at 8.0 GHz), communications bands under the family of 3GPP wireless communications standards, communications bands under the IEEE 802.XX family of standards, satellite communications bands such as an L-band, S-band (e.g., from 2-4 GHz), C-band (e.g., from 4-8 GHz), X-band, Ku-band (e.g., from 12-18 GHz), Ka-band (e.g., from 26-40 GHz), etc., industrial, scientific, and medical (ISM) bands such as an ISM band between around 900 MHz and 950 MHz or other ISM bands below or above 1 GHz, one or more unlicensed bands, one or more bands reserved for emergency and/or public services, and/or any other desired frequency bands of interest. Wireless circuitry  34  may also be used to perform spatial ranging operations if desired. 
     The UWB communications handled by radio-frequency transceiver circuitry  36  may be based on an impulse radio signaling scheme that uses band-limited data pulses. Radio-frequency signals in the UWB frequency band may have any desired bandwidths such as bandwidths between 499 MHz and 1331 MHz, bandwidths greater than 500 MHz, etc. The presence of lower frequencies in the baseband may sometimes allow ultra-wideband signals to penetrate through objects such as walls. In an IEEE 802.15.4 system, for example, a pair of electronic devices may exchange wireless time stamped messages. Time stamps in the messages may be analyzed to determine the time of flight of the messages and thereby determine the distance (range) between the devices and/or an angle between the devices (e.g., an angle of arrival of incoming radio-frequency signals). 
     Radio-frequency transceiver circuitry  36  may include respective transceivers (e.g., transceiver integrated circuits or chips) that handle each of these frequency bands or any desired number of transceivers that handle two or more of these frequency bands. In scenarios where different transceivers are coupled to the same antenna, filter circuitry (e.g., duplexer circuitry, diplexer circuitry, low pass filter circuitry, high pass filter circuitry, band pass filter circuitry, band stop filter circuitry, etc.), switching circuitry, multiplexing circuitry, or any other desired circuitry may be used to isolate radio-frequency signals conveyed by each transceiver over the same antenna (e.g., filtering circuitry or multiplexing circuitry may be interposed on a radio-frequency transmission line shared by the transceivers). Radio-frequency transceiver circuitry  36  may include one or more integrated circuits (chips), integrated circuit packages (e.g., multiple integrated circuits mounted on a common printed circuit in a system-in-package device, one or more integrated circuits mounted on different substrates, etc.), power amplifier circuitry, up-conversion circuitry, down-conversion circuitry, low-noise input amplifiers, passive radio-frequency components, switching circuitry, transmission line structures, and other circuitry for handling radio-frequency signals and/or for converting signals between radio-frequencies, intermediate frequencies, and/or baseband frequencies. 
     In general, radio-frequency transceiver circuitry  36  may cover (handle) any desired frequency bands of interest. As shown in  FIG.  2   , wireless circuitry  34  may include antennas  40 . Radio-frequency transceiver circuitry  36  may convey radio-frequency signals using one or more antennas  40  (e.g., antennas  40  may convey the radio-frequency signals for the transceiver circuitry). 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 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. 
     Antennas  40  in wireless circuitry  34  may be formed using any suitable antenna types. For example, antennas  40  may include antennas with resonating elements that are formed from stacked patch antenna structures, loop antenna structures, patch antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, waveguide structures, monopole antenna structures, dipole antenna structures, helical antenna structures, Yagi (Yagi-Uda) antenna structures, hybrids of these designs, etc. If desired, antennas  40  may include antennas with dielectric resonating elements such as dielectric resonator antennas. If desired, one or more of antennas  40  may be cavity-backed antennas. Two or more antennas  40  may be arranged in a phased antenna array if desired (e.g., for conveying centimeter and/or millimeter wave signals within a signal beam formed in a desired beam pointing direction that may be steered/adjusted over time). Different types of antennas may be used for different bands and combinations of bands. 
       FIG.  3    is a schematic diagram showing how a given antenna  40  may be fed by radio-frequency transceiver circuitry  36 . As shown in  FIG.  3   , antenna  40  may have a corresponding antenna feed  50 . Antenna  40  may include an antenna resonating (radiating) element and an antenna ground. Antenna feed  50  may include a positive antenna feed terminal  52  coupled to the antenna resonating element and a ground antenna feed terminal  44  coupled to the antenna ground. 
     Radio-frequency transceiver circuitry  36  may be coupled to antenna feed  50  using a radio-frequency transmission line path  42  (sometimes referred to herein as transmission line path  42 ). Transmission line path  42  may include a signal conductor such as signal conductor  46  (e.g., a positive signal conductor). Transmission line path  42  may include a ground conductor such as ground conductor  48 . Ground conductor  48  may be coupled to ground antenna feed terminal  44  of antenna feed  50 . Signal conductor  46  may be coupled to positive antenna feed terminal  52  of antenna feed  50 . 
     Transmission line path  42  may include one or more radio-frequency transmission lines. The radio-frequency transmission line(s) in transmission line path  42  may include stripline transmission lines (sometimes referred to herein simply as striplines), coaxial cables, coaxial probes realized by metalized vias, microstrip transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, waveguide structures, combinations of these, etc. Multiple types of radio-frequency transmission line may be used to form transmission line path  42 . Filter circuitry, switching circuitry, impedance matching circuitry, phase shifter circuitry, amplifier circuitry, and/or other circuitry may be interposed on transmission line path  42 , if desired. One or more antenna tuning components for adjusting the frequency response of antenna  40  in one or more bands may be interposed on transmission line path  42  and/or may be integrated within antenna  40  (e.g., coupled between the antenna ground and the antenna resonating element of antenna  40 , coupled between different portions of the antenna resonating element of antenna  40 , etc.). 
     If desired, one or more of the radio-frequency transmission lines in transmission line path  42  may be integrated into ceramic substrates, rigid printed circuit boards, and/or flexible printed circuits. In one suitable arrangement, the radio-frequency transmission lines may be 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) that may be folded or bent in multiple dimensions (e.g., two or three dimensions) and that 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 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). 
     If desired, conductive electronic device structures such as conductive portions of housing  12  ( FIG.  1   ) may be used to form at least part of one or more of the antennas  40  in device  10 .  FIG.  4    is a cross-sectional side view of device  10 , showing illustrative conductive electronic device structures that may be used in forming one or more of the antennas  40  in device  10 . 
     As shown in  FIG.  4   , peripheral conductive housing structures  12 W may extend around the lateral periphery of device  10  (e.g., as measured in the X-Y plane of  FIG.  1   ). Peripheral conductive housing structures  12 W may extend from rear housing wall  12 R (e.g., at the rear face of device  10 ) to display  14  (e.g., at the front face of device  10 ). In other words, peripheral conductive housing structures  12 W may form conductive sidewalls for device  10 , a first of which is shown in the cross-sectional side view of  FIG.  4    (e.g., a given sidewall that runs along an edge of device  10  and that extends across the width or length of device  10 ). 
     Display  14  may have a display module such as display module  62  (sometimes referred to as a display panel). Display module  62  may include pixel circuitry, touch sensor circuitry, force sensor circuitry, and/or any other desired circuitry for forming active area AA of display  14 . Display  14  may include a dielectric cover layer such as display cover layer  64  that overlaps display module  62 . Display cover layer  64  may include plastic, glass, sapphire, ceramic, and/or any other desired dielectric materials. Display module  62  may emit image light and may receive sensor input (e.g., touch and/or force sensor input) through display cover layer  64 . Display cover layer  64  and display  14  may be mounted to peripheral conductive housing structures  12 W. The lateral area of display  14  that does not overlap display module  62  may form inactive area IA of display  14 . 
     As shown in  FIG.  4   , rear housing wall  12 R may be mounted to peripheral conductive housing structures  12 W (e.g., opposite display  14 ). Rear housing wall  12 R may include a conductive layer such as conductive support plate  58 . Conductive support plate  58  may extend across an entirety of the width of device  10  (e.g., between the left and right edges of device  10  as shown in  FIG.  1   ). Conductive support plate  58  may be formed from an integral portion of peripheral conductive housing structures  12 W that extends across the width of device  10  or may include a separate housing structure attached, coupled, or affixed to peripheral conductive housing structures  12 W. 
     If desired, rear housing wall  12 R may include a dielectric cover layer such as dielectric cover layer  56 . Dielectric cover layer  56  may include glass, plastic, sapphire, ceramic, one or more dielectric coatings, or other dielectric materials. Dielectric cover layer  56  may be layered under conductive support plate  58  (e.g., conductive support plate  58  may be coupled to an interior surface of dielectric cover layer  56 ). If desired, dielectric cover layer  56  may extend across an entirety of the width of device  10  and/or an entirety of the length of device  10 . Dielectric cover layer  56  may overlap slot  60 . If desired, dielectric cover layer  56  be provided with pigmentation and/or an opaque masking layer (e.g., an ink layer) that helps to hide the interior of device  10  from view. In another suitable arrangement, dielectric cover layer  56  may be omitted and slot  60  may be filled with a solid dielectric material. 
     The housing for device  10  may also include one or more additional conductive support plates interposed between display  14  and rear housing wall  12 R. For example, the housing for device  10  may include a conductive support plate such as mid-chassis  65  (sometimes referred to herein as conductive support plate  65 ). Mid-chassis  65  may be vertically interposed between rear housing wall  12 R and display  14  (e.g., conductive support plate  58  may be located at a first distance from display  14  whereas mid-chassis  65  is located at a second distance that is less than the first distance from display  14 ). Mid-chassis  65  may extend across an entirety of the width of device  10  (e.g., between the left and right edges of device  10  as shown in  FIG.  1   ). Mid-chassis may be formed from an integral portion of peripheral conductive housing structures  12 W that extends across the width of device  10  or may include a separate housing structure attached, coupled, or affixed to peripheral conductive housing structures  12 W. One or more components may be supported by mid-chassis  65  (e.g., logic boards such as a main logic board, a battery, etc.) and/or mid-chassis  65  may contribute to the mechanical strength of device  10 . Mid-chassis may be formed from metal (e.g., stainless steel, aluminum, etc.). 
     Conductive support plate  58 , mid-chassis  65 , and/or display module  62  may have an edge  54  that is separated from peripheral conductive housing structures  12 W by dielectric-filled slot  60  (sometimes referred to herein as opening  60 , gap  60 , or aperture  60 ). Slot  60  may be filled with air, plastic, ceramic, or other dielectric materials. Conductive housing structures such as conductive support plate  58 , mid-chassis  65 , conductive portions of display module  62 , and/or peripheral conductive housing structures  12 W (e.g., the portion of peripheral conductive housing structures  12 W opposite conductive support plate  58 , mid-chassis  65 , and display module  62  at slot  60 ) may be used to form antenna structures for one or more of the antennas  40  in device  10 . For example, peripheral conductive housing structures  12 W may form an antenna resonating element arm (e.g., an inverted-F antenna resonating element arm) for one or more of the antennas  40  in device  10 . Mid-chassis  65 , conductive support plate  58 , and/or display module  62  may be used to form the corresponding antenna ground for one or more of the antennas  40  in device  10  and/or to form one or more edges of slot antenna resonating elements (e.g., slot antenna resonating elements formed from slot  60 ) for the antennas  40  in device  10 . One or more conductive interconnect structures  63  may electrically couple mid-chassis  65  to conductive support plate  58  and/or one or more conductive interconnect structures  63  may electrically couple mid-chassis  65  to conductive structures in display module  62  (sometimes referred to herein as conductive display structures) so that each of these elements form part of the antenna ground. The conductive display structures may include a conductive frame, bracket, or support for display module  62 , shielding layers in display module  62 , ground traces in display module  62 , etc. 
     Conductive interconnect structures  63  may serve to ground mid-chassis  65  to conductive support plate  58  and/or display module  62  (e.g., to ground conductive support plate  58  to the conductive display structures through mid-chassis  65 ). Put differently, conductive interconnect structures  63  may hold the conductive display structures, mid-chassis  65 , and/or conductive support plate  58  to a common ground or reference potential (e.g., as a system ground for device  10  that is used to form part of the antenna ground). Conductive interconnect structures  63  may therefore sometimes be referred to herein as grounding structures  63 , grounding interconnect structures  63 , or vertical grounding structures  63 . Conductive interconnect structures  63  may include conductive traces, conductive pins, conductive springs, conductive prongs, conductive brackets, conductive screws, conductive clips, conductive tape, conductive wires, conductive traces, conductive foam, conductive adhesive, solder, welds, metal members (e.g., sheet metal members), contact pads, conductive vias, conductive portions of one or more components mounted to mid-chassis  65  and/or conductive support plate  58 , and/or any other desired conductive interconnect structures. 
     If desired, device  10  may include multiple slots  60  and peripheral conductive housing structures  12 W may include multiple dielectric gaps that divide the peripheral conductive housing structures into segments (e.g., dielectric gaps  18  of  FIG.  1   ).  FIG.  5    is a top interior view showing how the lower end of device  10  (e.g., within region  22  of  FIG.  1   ) may include a slot  60  and may include multiple dielectric gaps that divide the peripheral conductive housing structures into segments for forming multiple antennas. Display  14  and other internal components have been removed from the view shown in  FIG.  5    for the sake of clarity. 
     As shown in  FIG.  5   , peripheral conductive housing structures  12 W may include a first conductive sidewall at the left edge of device  10 , a second conductive sidewall at the top edge of device  10  (not shown in  FIG.  5   ), a third conductive sidewall at the right edge of device  10 , and a fourth conductive sidewall at the bottom edge of device  10  (e.g., in an example where device  10  has a substantially rectangular lateral shape). Peripheral conductive housing structures  12 W may be segmented by dielectric-filled gaps  18  such as a first gap  18 - 1 , a second gap  18 - 2 , and a third gap  18 - 3 . Gaps  18 - 1 ,  18 - 2 , and  18 - 3  may be filled with plastic, ceramic, sapphire, glass, epoxy, or other dielectric materials. The dielectric material in the gaps may lie flush with peripheral conductive housing structures  12 W at the exterior surface of device  10  if desired. 
     Gap  18 - 1  may divide the first conductive sidewall to separate segment  66  of peripheral conductive housing structures  12 W from segment  68  of peripheral conductive housing structures  12 W. Gap  18 - 2  may divide the third conductive sidewall to separate segment  72  from segment of peripheral conductive housing structures  12 W. Gap  18 - 3  may divide the fourth conductive sidewall to separate segment  68  from segment  70  of peripheral conductive housing structures  12 W. In this example, segment  68  forms the bottom-left corner of device  10  (e.g., segment  68  may have a bend at the corner) and is formed from the first and fourth conductive sidewalls of peripheral conductive housing structures  12 W (e.g., in lower region  22  of  FIG.  1   ). Segment  70  forms the bottom-right corner of device  10  (e.g., segment  70  may have a bend at the corner) and is formed from the third and fourth conductive sidewalls of peripheral conductive housing structures  12 W (e.g., in lower region  22  of  FIG.  1   ). 
     Device  10  may include ground structures  78  (e.g., structures that form part of the antenna ground for one or more of the antennas in device  10 ). Ground structures  78  may include one or more metal layers such conductive support plate  58  ( FIG.  4   ), mid-chassis  65  ( FIG.  4   ), conductive display structures, conductive interconnect structures  63  ( FIG.  4   ), conductive traces on a printed circuit board, conductive portions of one or more components in device  10 , etc. Ground structures  78  may extend between opposing sidewalls of peripheral conductive housing structures  12 W. For example, ground structures  78  may extend from segment  66  to segment  72  of peripheral conductive housing structures  12 W (e.g., across the width of device  10 , parallel to the X-axis of  FIG.  5   ). Ground structures  78  may be welded or otherwise affixed to segments  66  and  72 . In another suitable arrangement, some or all of ground structures  78 , segment  66 , and segment  72  may be formed from a single, integral (continuous) piece of machined metal (e.g., in a unibody configuration). Ground structures  78  may include a ground extension  74  that protrudes into slot  60  and that may, if desired, bridge slot  60  and couple the ground structures to the peripheral conductive housing structures. Ground extension  74  may be formed from a data connector for device  10 . Device  10  may have a longitudinal axis  76  that bisects the width of device  10  and that runs parallel to the length of device  10  (e.g., parallel to the Y-axis). 
     As shown in  FIG.  5   , slot  60  may separate ground structures  78  from segments  68  and  70  of peripheral conductive housing structures  12 W (e.g., the upper edge of slot  60  may be defined by ground structures  78  whereas the lower edge of slot  60  is defined by segments  68  and  70 ). Slot  60  may have an elongated shape extending from a first end at gap  18 - 1  to an opposing second end at gap  18 - 2  (e.g., slot  60  may span the width of device  10 ). Slot  60  may be filled with air, plastic, glass, sapphire, epoxy, ceramic, or other dielectric material. Slot  60  may be continuous with gaps  18 - 1 ,  18 - 2 , and  18 - 3  in peripheral conductive housing structures  12 W if desired (e.g., a single piece of dielectric material may be used to fill both slot  60  and gaps  18 - 1 ,  18 - 2 , and  18 - 3 ). 
     Ground structures  78 , segment  66 , segment  68 , segment  70 , and portions of slot  60  may be used in forming multiple antennas  40  in the lower region of device  10  (sometimes referred to herein as lower antennas). For example, device  10  may include a first antenna  40 - 1  having an antenna resonating (radiating) element formed from segment  68  and having an antenna ground formed from ground structures  78 , device  10  may include a second antenna  40 - 2  having an antenna resonating element formed from segment  70  and having an antenna ground formed from ground structures  78 , may have a third antenna  40 - 3  having a slot antenna resonating element formed from a portion of slot  60  between segment  66  and ground structures  78 , and may have a fourth antenna  40 - 4  having a slot antenna resonating element formed from a portion of slot  60  between segment  72  and ground structures  78 . Antennas  40 - 1  and  40 - 2  may be, for example, inverted-F antennas having a return path that couples the respective resonating element arms to the antenna ground. Antennas  40 - 1 ,  40 - 2 ,  40 - 3 , and  40 - 4  may convey radio-frequency signals in one or more frequency bands. For example, antennas  40 - 1  and  40 - 2  may convey radio-frequency signals in at least the cellular low band, the cellular midband, and the cellular high band. This may allow antennas  40 - 1  and  40 - 2  to perform MIMO communications in one or more of these bands, thereby maximizing data throughput. 
     Antenna  40 - 1  may occupy a much smaller volume in device  10  than antenna  40 - 2 . It can therefore be difficult for antenna  40 - 1  to cover all frequencies of one or more frequency bands of interest with satisfactory antenna efficiency. If desired, antenna  40 - 1  may include a switchable loop path that helps to configure antenna  40 - 1  to cover all frequencies of one or more frequency bands of interest with satisfactory antenna efficiency.  FIG.  6    is an interior rear view showing how antenna  40 - 1  may include a switchable loop path (e.g., with dielectric cover layer  56  of  FIG.  4    removed). 
     As shown in  FIG.  6   , antenna  40 - 1  may have an antenna resonating element arm formed from segment  68  of peripheral conductive housing structures  12 W. Segment  68  may, for example, form an inverted-F antenna resonating element arm for antenna  40 - 1 . Antenna  40 - 1  may be fed using an antenna feed (e.g., antenna feed  50  of  FIG.  3   ) coupled across slot  60 . The antenna feed may have positive antenna feed terminal  52  coupled to segment  68  of peripheral conductive housing structures  12 W. In some implementations, positive antenna feed terminal  52  may also be switchably coupled to a point on segment  66  to directly feed segment  66 . More than one positive antenna feed terminal  52  may be coupled to different points on segment  68  if desired (e.g., positive antenna feed terminals coupled to different respective radio-frequency transmission line paths). If desired, antenna  40 - 1  may have one or more return paths and/or antenna tuning components (e.g., switchable capacitors, inductors, etc.) coupled between segment  68  and ground structures  78 . 
     Slot  60  may include a vertical portion that extends parallel to longitudinal axis  76  (FIG. and beyond gap  18 - 2 . As shown in  FIG.  6   , slot  60  may include an extended (elongated) portion  80 . Extended portion  80  of slot  60  may extend between segment  66  and ground structures  78  (e.g., segment  66  and ground structures  78  may define opposing edges of extended portion  126 ), parallel to longitudinal axis (the Y-axis in  FIG.  6   ). Extended portion  80  of slot  60  may have an open end at gap  18 - 2  and an opposing closed end  82  formed from ground structures  78 . Extended portion  80  of slot  60  may sometimes be referred to herein simply as slot  80 . Slot  80  may contribute to the frequency response of antenna  40 - 1 . 
     To selectively boost the frequencies covered by antenna  40 - 1 , antenna  40 - 1  may include a switchable loop path. As shown in  FIG.  6   , antenna  40 - 1  may include an antenna tuning element  88  that is used to form the switchable loop path. Tuning element  88  may be mounted to an underlying substrate such as flexible printed circuit  84 . Tuning element  88  may, for example, be surface-mounted to flexible printed circuit  84  (e.g., using solder) as a surface-mount technology (SMT) component. Tuning element  88  may sometimes be referred to herein as antenna tuning element  88 , tuning circuit  88 , tuning component  88 , switchable component  88 , switching circuitry  88 , or simply as tuner  88 . 
     Flexible printed circuit  84  may run along the interior surface of segment  66  (e.g., under a ledge or datum of segment  66 ). Flexible printed circuit  84  may include conductive traces  86 . Tuning element  88  may be interposed along or otherwise coupled to conductive traces  86 . Conductive traces  86  may include ground traces, control traces, and/or signal traces. The signal traces may convey radio-frequency signals for a corresponding radio-frequency transmission line path. The ground traces may be coupled to the antenna ground for antenna  40 - 1  (e.g., ground structures  78 ). The control traces may include one or more control paths that convey control signals for tuning element  88  (e.g., from control circuitry  38  of  FIG.  2   ). The control signals may adjust the tuning state of tuning element  88  (e.g., between two or more tuning states). 
     Tuning element  88  may have a first terminal (port) T 1 , a second terminal (port) T 2 , and a third terminal (port) T 3 . Tuning element  88  may include one or more inductors, resistors, capacitors, and/or switches coupled between conductive traces  86  and/or terminals T 1 , T 2 , and/or T 3  in any desired manner. The control signals provided over the control trace(s) in conductive traces  86  may dynamically change, adjust, or switch the tuning state of element  88  by controlling the switch(es) in tuning element  88  (e.g., to couple different complex impedances between any combination of terminals T 1 - 3  and/or conductive traces  86 ). The control signals may also adjust the inductance of one or more tunable inductors and/or adjust the capacitance of one or more tunable capacitors (e.g., varactors) in tuning element  88 . 
     As shown in  FIG.  6   , terminal T 2  of tuning element  88  may be coupled to point  94  on segment  66  of peripheral conductive housing structures  12 W. Point  94  may be located at or adjacent to gap  18 - 2  (e.g., on knuckle  90  of segment  66 ). Terminal T 3  of tuning element  88  may be coupled to point  96  on segment  68  over conductive path  100  (e.g., terminal T 3  of tuning element  88  may be coupled to segment  66  across gap  18 - 2 ). Point  96  may be located at or adjacent to gap  18 - 2  (e.g., on knuckle  92  of segment  68 ). Terminal T 1  of tuning element  88  may be coupled to point  98  on ground structures  78  over conductive path  108  (e.g., terminal T 1  of tuning element  88  may be coupled to ground structures  78  across slot  80 ). 
     Point  96  on segment  68  may also be coupled to point  104  on ground structures  78  over conductive path  102  (e.g., across slot  60 ). Point  104  may be separated from point  98  by portion  106  of ground structures  78  (e.g., along the edge of ground structures  78  defining slot  60 ). Conductive screws, conductive adhesive, solder, welds, conductive clips, conductive pins, conductive springs, conductive brackets, and/or any other desired conductive interconnect structures may be used to couple conductive path  102  to points  96  or  104 , to couple conductive path  100  to terminal T 3  or point  96 , to couple terminal T 2  to point  94 , and/or to couple conductive path  108  to point  98  or terminal T 1 . 
     Conductive paths  100 ,  102 , and  108  may include conductive traces (e.g., on one or more underlying flexible printed circuits or other substrates), wires, and/or any other desired conductive interconnect structures. If desired, an antenna tuning element  110  may be disposed on conductive path  100 . Additionally or alternatively, an antenna tuning element  112  may be disposed on conductive path  102 . Additionally or alternatively, an antenna tuning element  114  may be disposed on conductive path  108 . Antenna tuning elements  110 ,  112 , and/or  114  may include any desired inductors, resistors, capacitors, and/or switches arranged in any desired manner. As one example, antenna tuning elements  114  and  112  may each include single-pole three-throw (SP3T) switches and corresponding inductors (e.g., switchable inductors) whereas antenna tuning element  110  includes a single-pole single-throw (SPST) switch. Antenna tuning elements  110 ,  112 , and/or  114  may be adjusted (e.g., using control signals) to adjust the electrical length of loop path  116 , thereby tuning the frequency response of the antenna in one or more desired frequency bands. Antenna tuning elements  110 ,  112 , and/or  114  may be omitted. If desired, point  94  may be coupled to positive antenna feed terminal  52  over a corresponding conductive path and antenna tuning element (not shown). 
     In some implementations that are described herein as examples, tuning element  88  may include an SP3T coupled between terminals T 1 -T 3  and/or ground traces in conductive traces  86 . The SP3T may include three field-effect transistors (FETs), for example. Tuning element  88  may have a first tuning state (e.g., a state in which each FET is turned on or provided with an asserted gate voltage so current flows between its source/drain terminals). When tuning element  88  is in the first tuning state, an antenna loop path is switched into use and incorporated into the resonating element arm of antenna  40 - 1 . In this first tuning state, tuning element  88  may form a loop path from terminal T 3  (or from ground traces on flexible printed circuit  84  to terminal T 3 ), through conductive path  100  to point  96  on segment  68  (e.g., across gap  18 - 2 ), through conductive path  102  from point  96  to point  104  (e.g., across slot  60 ), from point  104  to point  98  through portion  106  of ground structures  78 , from point  98  to terminal T 1  (e.g., across slot  80 ), from terminal T 1  to terminal T 2 , and from terminal T 2  to point  94  on segment  66 , as shown by arrow  116 . Arrow  116  may therefore sometimes be referred to herein as loop path  116 , antenna loop path  116 , switchable loop path  116 , or switchable antenna loop path  116 . 
     When tuning element  88  is in the first tuning state (mode), loop path  116  is formed (e.g., switched into use) within antenna  40 - 1  and corresponding antenna currents flow along loop path  116 . Loop path  116  may contribute an additional resonance to antenna  40 - 1  (e.g., to the resonance of slot  60 , slot  80 , segment  66 , and/or segment  68 ) that serves to boost the antenna efficiency of antenna  40 - 1  at one or more frequencies, such as in the cellular UHB between 3300 MHz and 5000 MHz (e.g., in a fundamental and/or one or more harmonic modes of the loop path). Tuning element  88  may also have a second tuning state (mode) in which loop path  116  is decoupled from antenna  40 - 1  (e.g., switched out of use) and no longer contributes a radiative response for the antenna (e.g., by forming infinite or open circuit impedances at one or more of terminals T 1 -T 3 ). The control signals on conductive traces  86  may place tuning element  88  into the first tuning state when radio-frequency signals are conveyed in the frequency band covered by loop path  116  (e.g., between 3300 MHz and 5000 MHz) and may place tuning element  88  into the second tuning state when this coverage is not needed, for example. The example of  FIG.  6    is merely illustrative. Loop path  116  and the other structures of antenna  40 - 1  may have other shapes. 
       FIG.  7    is a plot showing how tuning element  88  and loop path  116  may boost performance of antenna  40 - 1  in a corresponding frequency band B. Curve  118  plots the antenna efficiency of antenna  40 - 1  when tuning element  88  is in the second tuning state or in implementations where loop path  116  (e.g., tuning element  88 , conductive path  108 , conductive path  100 , and/or conductive path  102 ) is omitted. As shown by curve  118 , antenna  40 - 1  may exhibit a relatively low antenna efficiency across frequency band B in these scenarios. Frequency band B may be, for example, the cellular UHB (e.g., 3300-5000 MHz). 
     Curve  120  plots the antenna efficiency of antenna  40 - 1  when tuning element  88  is in the first tuning state, where loop path  116  is coupled between point  94  and terminal T 3  of tuning element  88  in antenna  40 - 1  (e.g., across slot  60 , slot  80 , and gap  18 - 2  between segments  66  and  68 ). As shown by curve  120 , antenna  40 - 1  may exhibit a relatively high antenna efficiency across frequency band B when antenna  40 - 1  has been configured by tuning element  88  to include loop path  116 . The example of  FIG.  7    is merely illustrative. In practice, curves  118  and  120  may have other shapes. Frequency band B may include any desired frequencies. 
     Device  10  may gather and/or use personally identifiable information. It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users. 
     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: 20220624
Publication Date: 20240813
Grant Date: 20240813
Priority Date: 20220624
Inventors: AYALA VAZQUEZ, ENRIQUE
XU, YUANCHENG
HU, HONGFEI
XU, HAO
WANG, Yiren
WANG, HAN
JAIN, Sidharath
KAMMERSGAARD, NIKOLAJ PETER IVERSEN
TIAN, Haozhan
TAO, YUAN
DI NALLO, CARLO
PASCOLINI, MATTIA
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q5/364", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/378", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/328", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/28", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q25/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/241", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/25", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/48", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/0464", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q5/314", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/247", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/42", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q9/0442", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q5/364", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/247", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 89246956