Electronic devices with interconnected ground structures

An electronic device may include wireless circuitry having one or more antennas. An antenna ground for an antenna may be formed from two separate conductive ground structures coupled to each other via a conductive interconnect structure. A slot element may be formed in one of the conductive ground structures to reject signals at one or more victim frequencies resulting from spurious signals generated by a non-ohmic contact formed between the conductive interconnect structure and the one of the conductive ground structures. The conductive interconnect structure may overlap and excite the slot element, which serves as an ineffective radiator at the one or more victim frequencies.

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.

Antenna components, especially in compact devices, often include multiple ground structures that are interconnected. Improperly interconnected ground structures have the potential to interfere with the operation of wireless components in a wireless device. As such, care must be taken when implementing antenna components such as ground structures in an electronic device.

SUMMARY

An electronic device may include wireless circuitry having one or more antennas. Multiple separate conductive ground structures may be coupled to each other via a conductive interconnect structure. The collective interconnected structures may form an antenna ground for one or more of the antennas. In some illustrative configurations, the conductive interconnect structure may form a non-ohmic contact with the ground structures, thereby introducing a spurious signal source. The spurious signal source may cause aggressor portions of the wireless circuitry to undesirably influence victim portions of the wireless circuitry. As an example, the spurious signal source may generate at a harmonic victim frequency based on radio-frequency signals at a fundamental aggressor frequency.

One or more of the conductive ground structures may include a slot element configured to reject signals at one or more victim frequencies resulting from the spurious signal source. The conductive interconnect structure may overlap and excite the slot element, which serves as an ineffective radiator at the one or more victim frequencies thereby reducing the impact of signals at the one or more victim frequencies on the victim portions of the wireless circuitry. With the implementation of the slot element, the conductive ground structure may exhibit localized standing waves around the slot element instead of across the entirety of the conductive ground structure.

If desired, the multiple separate conductive ground structures may be formed from conductive portions of a display assembly such as a display backplate and a display (cover layer) frame structure.

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.

Device10may be a portable electronic device or other suitable electronic device. For example, device10may 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. 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, a 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 (e.g., a dielectric cover layer). Housing12may also have shallow grooves that do not pass entirely through housing12. The slots and grooves may be filled with plastic or other dielectric materials. 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. Conductive portions of peripheral structures12W and conductive portions of 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). In other words, device10may 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 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 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 structures12W 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 structures12W.

It is not necessary for peripheral conductive housing structures12W to have a uniform cross-section. For example, the top portion of peripheral conductive housing structures12W may, if desired, have an inwardly protruding ledge that helps hold display14in place. The bottom portion of peripheral conductive housing structures12W may also have an enlarged lip (e.g., in the plane of the rear surface of device10). Peripheral conductive housing structures12W 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 structures12W serve as a bezel for display14), peripheral conductive housing structures12W may run around the lip of housing12(i.e., peripheral conductive housing structures12W may cover only the edge of housing12that surrounds display14and not the rest of the sidewalls of housing12).

Rear housing wall12R may lie in a plane that is parallel to display14. In configurations for device10in which some or all of rear housing wall12R is formed from metal, it may be desirable to form parts of peripheral conductive housing structures12W as integral portions of the housing structures forming rear housing wall12R. For example, rear housing wall12R of device10may include a planar metal structure and portions of peripheral conductive housing structures12W 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. Rear housing wall12R may have one or more, two or more, or three or more portions. Peripheral conductive housing structures12W and/or conductive portions of 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/cover 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 peripheral conductive housing structures12W and/or conductive portions of rear housing wall12R 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 of display14may 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. Inactive area IA may include a recessed region such as notch24that extends into active area AA. Active area AA may, for example, be defined by the lateral area of a display module for display14(e.g., a display module that includes pixel circuitry, touch sensor circuitry, etc.). The display module may have a recess or notch in upper region20of device10that is free from active display circuitry (i.e., that forms notch24of inactive area IA). Notch24may 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 structures12W.

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 port16in notch24or a microphone port. 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 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 conductive support plate or backplate) that spans the walls of housing12(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 structures12W). The conductive support plate may form an exterior rear surface of device10or 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 device10and/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 wall12R). 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.

In regions22and20, openings may be formed within the conductive structures of device10(e.g., between peripheral conductive housing structures12W and opposing conductive ground structures such as conductive portions of 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 regions22and20may 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 regions22and20. 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 regions22and20), thereby narrowing the slots in regions22and20. Region22may sometimes be referred to herein as lower region22or lower end22of device10. Region20may sometimes be referred to herein as upper region20or upper end20of device10.

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 lower region22and/or upper region20of 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 peripheral conductive housing structures12W may be provided with peripheral gap structures. For example, peripheral conductive housing structures12W may be provided with one or more dielectric-filled gaps such as gaps18, as shown inFIG.1. The gaps in peripheral conductive housing structures12W may be filled with dielectric such as polymer, ceramic, glass, air, other dielectric materials, or combinations of these materials. Gaps18may divide peripheral conductive housing structures12W into one or more peripheral conductive segments. The conductive segments that are formed in this way may form parts of antennas in device10if desired. Other dielectric openings may be formed in peripheral conductive housing structures12W (e.g., dielectric openings other than gaps18) and may serve as dielectric antenna windows for antennas mounted within the interior of device10. Antennas within device10may be aligned with the dielectric antenna windows for conveying radio-frequency signals through peripheral conductive housing structures12W. Antennas within device10may also be aligned with inactive area IA of display14for conveying radio-frequency signals through display14.

In a typical scenario, device10may have one or more upper antennas and one or more lower antennas. An upper antenna may, for example, be formed in upper region20of device10. A lower antenna may, for example, be formed in lower region22of device10. Additional antennas may be formed along the edges of housing12extending between regions20and22if 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 device10. The example ofFIG.1is merely illustrative. If desired, housing12may 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 device10is shown inFIG.2. As shown inFIG.2, device10may include control circuitry38. Control circuitry38may include storage such as storage circuitry30. Storage circuitry30may 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 circuitry38may include processing circuitry such as processing circuitry32. Processing circuitry32may be used to control the operation of device10. Processing circuitry32may 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 circuitry38may 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 circuitry30(e.g., storage circuitry30may 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 circuitry30may be executed by processing circuitry32.

Control circuitry38may be used to run software on device10such 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 circuitry38may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry38include 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.

Device10may include input-output circuitry26. Input-output circuitry26may include input-output devices28. Input-output devices28may be used to allow data to be supplied to device10and to allow data to be provided from device10to external devices. Input-output devices28may 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 circuitry26may include wireless circuitry such as wireless circuitry34for wirelessly conveying radio-frequency signals. While control circuitry38is shown separately from wireless circuitry34in the example ofFIG.2for the sake of clarity, wireless circuitry34may include processing circuitry that forms a part of processing circuitry32and/or storage circuitry that forms a part of storage circuitry30of control circuitry38(e.g., portions of control circuitry38may be implemented on wireless circuitry34). As an example, control circuitry38may include baseband processor circuitry or other control components that form a part of wireless circuitry34.

Wireless circuitry34may 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 circuitry34may include radio-frequency transceiver circuitry36for 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 circuitry36may 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 circuitry34may also be used to perform spatial ranging operations if desired.

Radio-frequency transceiver circuitry36may 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 circuitry36may 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 circuitry36may cover (handle) any desired frequency bands of interest. As shown inFIG.2, wireless circuitry34may include antennas40. Radio-frequency transceiver circuitry36may convey radio-frequency signals using one or more antennas40(e.g., antennas40may 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). Antennas40may transmit the radio-frequency signals by radiating the radio-frequency signals into free space (or to free space 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.

Antennas40in wireless circuitry34may be formed using any suitable antenna types. For example, antennas40may 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, antennas40may include antennas with dielectric resonating elements such as dielectric resonator antennas. If desired, one or more of antennas40may be cavity-backed antennas. Two or more antennas40may 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.3is a schematic diagram showing how a given antenna40may be fed by radio-frequency transceiver circuitry36. As shown inFIG.3, antenna40may have a corresponding antenna feed50. Antenna40may include an antenna resonating (radiating) element and an antenna ground. Antenna feed50may include a positive antenna feed terminal52coupled to the antenna resonating element and a ground antenna feed terminal44coupled to the antenna ground.

Radio-frequency transceiver circuitry36may be coupled to antenna feed50using a radio-frequency transmission line path42(sometimes referred to herein as transmission line path42). Transmission line path42may include a signal conductor such as signal conductor46(e.g., a positive signal conductor). Transmission line path42may include a ground conductor such as ground conductor48. Ground conductor48may be coupled to ground antenna feed terminal44of antenna feed50. Signal conductor46may be coupled to positive antenna feed terminal52of antenna feed50.

Transmission line path42may include one or more radio-frequency transmission lines. The radio-frequency transmission line(s) in transmission line path42may 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 path42. Filter circuitry, switching circuitry, impedance matching circuitry, phase shifter circuitry, amplifier circuitry, and/or other circuitry may be interposed on transmission line path42, if desired. One or more antenna tuning components for adjusting the frequency response of antenna40in one or more bands may be interposed on transmission line path42and/or may be integrated within antenna40(e.g., coupled between the antenna ground and the antenna resonating element of antenna40, coupled between different portions of the antenna resonating element of antenna40, etc.).

If desired, one or more of the radio-frequency transmission lines in transmission line path42may 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).

FIG.4is a schematic diagram showing how illustrative ground structures may be implemented within device10. In particular, to implement an electrical ground for components such as an antenna ground for one or more of antennas40in device10as described in connection withFIG.3, device10may include multiple ground structures60(e.g., structures that collectively form part of the antenna ground for one or more of antennas40in device10). The multiple ground structures may include a number of discrete individual elements, illustratively shown inFIG.4as a ground structure62, a ground structure64, and other additional ground structures66. Two or more of these individual ground elements may be electrically interconnected using conductive grounding interconnect structures such as interconnect element68which connects ground structure62to ground structure64, as shown inFIG.4.

Various elements in device10may serve as each of the ground structures60for one or more of antennas40on device10. As examples, ground structures60may include conductive portions of a display module or display assembly, one or more metal layers such as a metal layer used to form a rear housing wall and/or an internal support structure for device10(e.g., a conductive structural support plate for device10), one or more other conductive portions of housing12such as conductive portions of sidewalls12W, conductive traces on a printed circuit board, conductive portions of one or more components in device10, and/or other conductive elements in device10. As further examples, conductive interconnect structures (e.g., conductive interconnect structure68) in ground structures60may include conductive adhesive, conductive tape, conductive foam, conductive springs, conductive pins, welds, and/or other conductive elements that serve to electrically (and if desired, physically) interconnect two or more individual ground structures.

When multiple pieces of individual antenna ground structures are interconnected, a common and effectively enlarged antenna ground plane may be formed within device10for one or more of antennas40, thereby enhancing antenna performance. This may be especially advantageous in a compact or small form factor device where a single continuous piece of antenna ground plane may take up valuable space within the device and may not easily conform to the form factor of the device, and is therefore undesirable. The interconnected ground structures may also implement desired antenna ground plane geometries and exhibit other desired characteristics to enhance antenna performance.

However, interconnecting individual antenna ground structures can sometimes lead to the introduction of spurious signal sources that can disrupt wireless communications of device10. As examples, when using some types of conductive interconnect structures such as conductive adhesive, conductive tape, conductive foam, or other conductive interconnect structures conducive to forming non-ohmic contacts (e.g., contacts that exhibit non-linear voltage-current behavior) to one or more of the interconnected ground structures, these conductive interconnect structures (along with their non-ohmic contacts) may serve as spurious signal sources. In other words, when radio-frequency signals are being conveyed by an antenna40containing the interconnected antenna ground structures (e.g., the conductive interconnect structure forms a part of the antenna ground to which the antenna feed for antenna40is connected), the non-linear characteristic of the contact may result in the generation of harmonic frequency signals (e.g., signals at one or more harmonics or integer multiples of the frequencies of conveyed signals), and/or intermodulated frequency signals (e.g., signals at one or more non-harmonic frequencies of the conveyed signals resulting from the mixing of two or more conveyed signals), which are collectively referred to herein as spurious signals. As examples, the harmonic frequency signals may include second-order harmonics, third-order harmonics, etc. As examples, the intermodulated frequency signals may include second-order intermodulation products, third-order intermodulation products, fifth-order intermodulation products, etc.

As an example, an antenna40may have an antenna ground that includes ground structures62and64and conductive interconnect structure68inFIG.4. In scenarios where conductive interconnect structure68is connected to ground structure62(and/or ground structure4) via a non-ohmic contact, conductive interconnect structure68(and its non-ohmic contact) may form a spurious signal source.

FIG.5is a schematic diagram showing how the generation of spurious signals may impact wireless communications of a wireless device in an illustrative example. As shown inFIG.5, a wireless device such as device10may include wireless circuitry70(forming a portion of wireless circuitry34inFIG.2) configured to convey radio-frequency signals72at a set of frequencies (e.g., in one or more frequency bands). In one illustrative configuration, wireless circuitry70may include an antenna and a radio that uses the antenna to convey radio-frequency signals72. In particular, radio-frequency signals72may be conveyed to an antenna resonating element as well as an antenna ground of the antenna that contains a conductive interconnect structure forming spurious signal source74(e.g., in the manner as described above). In other words, while radio-frequency signals72are being conveyed into freespace, corresponding radio-frequency signals72are also being conveyed to spurious signal source74in the antenna ground for wireless circuitry70(e.g., via a ground conductor48and a corresponding ground feed terminal44inFIG.3).

In the example ofFIG.5, spurious signal source74may generate spurious radio-frequency signals76based on received radio-frequency signals72. As examples, spurious radio-frequency signals76may include one or more harmonic frequency signals or signals at harmonics of the frequencies of radio-frequency signals72, one or more intermodulated frequency signals or signals (at non-harmonic frequencies) resulting from the mixing of radio-frequency signals72of different frequencies, and/or other spurious signals resulting from other radio-frequency signals. Configurations in which radio-frequency signals76include harmonic frequency signals are described herein as an illustrative example.

In the example of spurious harmonic radio-frequency signals76being generated, one or more of the interconnected ground structures may exhibit standing waves (e.g., a standing wave current and/or voltage distribution) across its entire structure. This can undesirably cause radiation of and further propagate spurious radio-frequency signals76. Wireless circuitry78in device10(forming a portion of wireless circuitry34inFIG.2) different from wireless circuitry portion70may perceive (e.g., receive) and be adversely impacted by the propagated spurious harmonic radio-frequency signals76. In particular, wireless circuitry78may be sensitive to radio-frequency signals at the frequencies of radio-frequency signals76.

As an example, wireless circuitry78may include an antenna and a corresponding radio that uses the antenna to convey radio-frequency signals at a set of frequencies (e.g., in one or more frequency bands), which overlap or include the frequencies of spurious radio-frequency signals76. In this scenario, wireless circuitry78may receive the radiated spurious signals76, which adversely impacts the operation of wireless circuitry78(e.g., by increasing the noise floor level, thereby decreasing signal-to-noise ratio, for signals received at wireless circuitry78).

Because the conveyance of radio-frequency signals at wireless circuitry70ultimately results in spurious signals that impact other wireless circuitry, wireless circuitry70may sometimes be referred to as aggressor wireless circuitry70(e.g., having one or more aggressor radios and antennas that convey radio-frequency signals that result in the spurious signals). The one or more frequencies of radio-frequency signals72resulting in the spurious signals may sometimes be referred to as one or more aggressor frequencies.

Because wireless circuitry78receives spurious signals resulting from radio-frequency signals from other wireless circuitry, wireless circuitry78may sometimes be referred to as victim wireless circuitry78(e.g., having one or more victim radios and antennas that receive and process the spurious signals). The one or more frequencies of spurious radio-frequency signals76may sometimes be referred to as one or more victim frequencies. In the example of harmonics interference, the one or more aggressor frequencies may be at fundamental frequencies, while the one or more victim frequencies are the harmonics of these fundamental frequencies.

In some illustrative configurations described herein as an example, the aggressor wireless circuitry may be associated with a cellular radio and one or more antennas coupled to the cellular radio, and the aggressor frequencies may be one or more frequencies in a cellular low band (e.g., at a frequency of 600 MHz). In this example, the victim wireless circuitry may be associated with a Bluetooth® radio and/or a Wi-Fi® radio and one or more antennas coupled to these radios, and the victim frequencies may be one or more frequencies in a 2.4 GHz Bluetooth® band, in a 2.4 GHz WLAN band, in a 5 GHz WLAN band (e.g., at a frequency of 2.4 GHz, at a frequency of 5.5 GHz, etc.). These frequencies are merely illustrative. In other scenarios, frequencies in one or more other frequency bands may impact or be impacted in a similar manner.

The impacts of spurious signals described above in connection withFIG.5are merely illustrative. In general, the existence of one or more spurious signal sources and radiation of corresponding spurious radio-frequency signals may interfere with the operation of any portion of wireless circuitry34(FIG.1) or other components in device10.

To mitigate the above-mentioned issues resulting from one or more spurious signal sources such as spurious signal source74, ground structures60may include corresponding slot elements such as slot element80coupled to spurious signal source74. In other words, a first ground structure, to which a second ground structure is connected via a conductive interconnect structure, may have a slot element80formed therein. Slot element80may be formed at the (non-ohmic) contact between the conductive interconnect structure and the first ground structure. The conductive interconnect structure may overlap and therefore be coupled to slot element80.

In such a manner, when radio-frequency signals72are received at the second ground structure (e.g., via an antenna feed terminal coupled to the second ground structure) and conveyed to the first ground structure as spurious radio-frequency signals76by way of the conductive interconnect structure and the non-ohmic contact serving as spurious signal source74, slot element80may stop the propagation of the generated spurious radio-frequency signals76onto the entire structure of the first ground structure (as standing waves). Instead, spurious radio-frequency signals76may be locally coupled onto slot element80.

In other words, when slot element80is excited by the reception of spurious radio-frequency signals76, the portion of the first ground structure defining the boundaries of slot element80(instead of the entirety of the first ground structure) exhibits standing waves corresponding to spurious radio-frequency signals76. Slot element80may be configured to reject one or more (victim) frequencies of interest (e.g., may have dimensions that efficiently radiate at frequencies outside of the one or more frequencies of interest). This local excitation of slot element80can help reduce the intensity or amplitude of the standing waves at the one or more victim frequencies of spurious signals76(relative to scenarios in which standing waves are exhibited across the entirety of a ground structure).

FIG.6is a top-down view of an illustrative slot element implemented within ground structures60(inFIG.4). In particular,FIG.6shows illustrative portions of the two individual ground structures62and64, with slot element80formed within the illustrated portion of ground structure62.

Slot element80may be a dielectric-filled opening within conductive material (e.g., conductive ground structure62). The opening of slot element80may be filled with dielectric material such as air or solid dielectric material. In the configuration ofFIG.6, slot element80(sometimes referred to herein as slot80, opening80, notch80, interference-mitigating slot element80, spurious signal mitigating slot element80, or victim frequency rejection structure80) is a closed slot, because portions of ground structure62completely surround and enclose slot80along lateral peripheral edges. If desired, slot element80may be implemented as an open slot formed in ground structure62(e.g., by forming slot element80such that one of its lateral peripheral edges extends to a peripheral edge of ground structure62and the slot element is not completely surrounded by conductive material).

To interconnect the two pieces of ground structure62and64and thereby form a common antenna ground, conductive interconnect structure68may extend from ground structure62to ground structure64. In particular, interconnect structure68may electrically and/or physically connect ground structure62to ground structure64. In the example ofFIG.6, interconnect structure68may have an elongated shape with one end coupled to (e.g., contacting) ground structure62at one or more locations84and one or more locations86and an opposing end coupled to (e.g., contacting) ground structure64at one or more locations88. More specifically, interconnect structure68may contact ground structure62at locations along opposing edges of ground structure62defining respective elongated sides of slot element80. In such a manner, interconnect structure68and its contacts at locations84and86may be configured to excite, feed, or otherwise cause slot element80to exhibit standing waves along its perimeter (e.g., along the perimeter of ground structure portion that defines slot element80) when (spurious) radio-frequency signals are conveyed from interconnect structure68onto the portion of ground structure62surrounding and defining slot element80.

In the example ofFIG.6, slot element80is an elongated rectangular slot element having a length82and a width83. In general, slot elements tend to exhibit response peaks when the slot perimeter is equal to a target effective wavelength (e.g., where the slot perimeter is equal to two times length82plus two times width83). The effective wavelength may be equal to a freespace wavelength multiplied by a constant value that is determined by the dielectric materials in and surrounding slot element80. In elongated slot elements where the length is much greater than the width (e.g., the length greater than four times the width, the length greater than eight times the width, the length greater than ten times the width, the length greater than twenty times the width, the length greater than fifty times the width, etc.), the response peaks may be exhibited when the slot length is approximately half of the target wavelength (e.g., is slightly less than half of the target wavelength given a non-zero slot width).

To reduce the effectiveness of the radiation of spurious radio-frequency signals at victim frequencies, slot element80may be configured to have dimensions that reduce the frequency response at the victim or spurious signal frequencies. In other words, slot element80may have dimensions that are not conducive to response peaks at the victim or spurious signal frequencies (e.g., response peaks are generated at frequencies different from the victim frequencies). As such, when interconnect structure68(at its contacts to ground structure62) excites slot element80at the victim signal frequencies, the amplitudes of standing wave current flowing around the perimeter of slot element80(e.g., between contacts at locations84and86) at these frequencies may be reduced (relative to scenarios where the dimensions of slot element80are designed to effectively radiate at the victim frequencies). This allows slot element80to serve as an inefficient radiator at these frequencies and therefore an inefficient propagator of spurious signals. By effectively dissipating signals at these victim frequencies (sometimes referred to herein as rejecting victim frequencies), slot element80may therefore reduce the effect of spurious signals (when generated by a spurious signal source) on victim wireless circuitry.

In illustrative configurations described herein as examples, slot element80may be elongated. In these examples, to reject certain frequencies and their corresponding wavelengths, slot element80may have a length less than one-half of the target wavelength, less than one-fourth of the target wavelength, less than one-eighth of the target wavelength, greater than one-tenth of the target wavelength, greater than one-eighth of the target wavelength, greater than one-fourth of the target wavelength, etc. In scenarios where a single victim frequency exists (e.g., victim wireless circuitry is sensitive to only one frequency of spurious signals), the target wavelength may be the wavelength corresponding to the victim frequency (e.g., based on the wave speed or speed of light, accounting for nearby dielectric effects that result in the use of an effective wavelength as described above, etc.). In scenarios where multiple victim frequencies exist (e.g., victim wireless circuitry is sensitive to multiple frequencies of spurious signals), the target wavelength may be the wavelength corresponding to the lowest victim frequency in the multiple victim frequencies. By configuring slot element80to reject the lowest of the victim frequencies (e.g., having the longest of wavelengths) in the manner described above, the same configuration for slot element80also rejects the higher victim frequencies.

In illustrative configurations where victim frequencies are in a 2.4 GHz WPAN band, in a 2.4 GHz WLAN band, and in a 5 GHz WLAN band (e.g., at a frequency of 2.4 GHz, at a frequency of 5.5 GHz, etc.), the length of elongated slot element may be 60 mm (e.g., approximately a length of one-half of the target wavelength associated with a victim frequency of 2.4 GHz), 30 mm (e.g., approximately a length of one-half of the target wavelength associated with a victim frequency of 5.5 GHz), 10 mm (e.g., approximately a length of one-tenth of the target wavelength associated with a victim frequency of 2.4 GHz), or any other length to suitably reject these victim frequencies. It may be desirable to configure the elongated slot element with a length closer to one-eighth to one-tenth of the target wavelength to more effectively reject the set of the victim frequencies. However, given manufacturing, form factor, and/or other constraints, the length of the elongated slot element may be adjusted from this range to more suitably accommodate other constraints.

The use of elongated slot element and consequently the consideration of slot length may serve as illustrative and approximate examples for rejecting victim frequencies. If desired, other properties of slot elements such as slot width may also be configured (along with slot length) to provide a slot element for rejecting victim frequencies.

Conductive interconnect structure68may be coupled across slot element80at a location along the elongated edges of ground structure62(e.g., at a location along length82). If desired, the location along the length of the slot across which interconnect structure68is coupled may be adjusted for impedance control (e.g., to control impedance matching between interconnect structure68and slot element80) to enhance rejection of victim frequencies (e.g., decrease frequency response at victim frequencies).

Configurations in which interconnect structure68is a conductive tape are sometimes described herein as examples. In these configurations, the conductive tape may be physically adhered to ground structure62at locations84and86across slot element80and may be physically adhered to ground structure64at locations88. Simultaneously, these contact locations may also serve as points of electrical (non-ohmic) contact (e.g., provide a low resistance or shorting path between ground structure62and interconnect structure68and provide a low resistance or shorting path between ground structure64and interconnect structure68, thereby forming a low resistance or shorting path between ground structures62and64via interconnect structure68). If desired, the conductive tape may bridge across a lateral gap (absence of conductive material) between ground structure62and ground structure64.

As other examples, interconnect structure68may be a conductive adhesive (e.g., a layer of conductive adhesive material deposited over ground structures62and64), a conductive foam (e.g., conductive foam interposed or vertically stacked between ground structures62and64), other interconnect structures configured to form non-ohmic contacts, and/or a combination of multiple types of interconnect structures.

While shown inFIG.6to extend laterally across and to overlap non-overlapping ground structures62and64, this configuration of interconnect structure68inFIG.6is merely illustrative. If desired, the illustrated portions of ground structures62and64may vertically overlap one another, and interconnect structure68may be disposed within the vertical gap between ground structures62and64and extend between (e.g., be sandwiched between) ground structures62and64.

In general, device10may include different individual ground structures oriented relative to one another in different manners and may include interconnect structures connecting the individual ground structures in various orientations. In any of these configurations, one or more slot elements such as slot element80may be provided to mitigate the undesired propagation of spurious signals (at one or more victim frequencies).

In some illustrative configurations, an antenna feed terminal (e.g., ground antenna feed terminal44inFIG.3) may be coupled to conductive ground structure64, and slot element80may be formed in a downstream interconnected ground structure62(e.g., a ground structure distal to but interconnected via a non-ohmic contact from the ground structure directly connected to the antenna feed terminal). If desired, conductive ground structure64may include an analogous slot element (e.g., configured to reject one or more target victim frequencies) instead of or in additional to slot element80in ground structure62.

The configuration of slot element80inFIG.6is merely illustrative. In general, slot element80may have any desired shape (e.g., with dimensions that impart the above-mentioned rejection of victim frequencies). For example, slot element80may have a meandering shape with different segments extending in different directions, may have straight and/or curved edges, etc.

While shown in the example ofFIG.6to be formed in ground structure62, a victim frequency rejection slot element (e.g., configured in the same manner as slot element80) may formed in ground structure64in addition to or instead of slot element80in ground structure62.

Conductive elements implementing antenna ground structures62and64(e.g., one or both of which including a respective victim frequency rejection slot element) may be formed from any desired (grounded) conductive electronic device structures. As one illustrative example, antenna ground structure62(and antenna ground structure64) may be formed from conductive structures associated with display14(FIG.1) or generally a display module or display assembly.

FIGS.7and8are illustrative views of conductive structures in a display configured to form the illustrative ground structures and victim frequency rejection structure (e.g., slot element80) as described in connection withFIGS.5and6.FIG.7is a plan view of illustrative interior display structures in a display module or display assembly for a display14of device10.

As shown inFIG.7, display module89may include a conductive display backplate90and a conductive frame structure92. Display backplate90may be separated from frame structure92by a non-conductive gap94. To expand the area of the (antenna) ground structures in device10, it may be desirable to connect frame structure92to backplate90to form an expanded ground plane using both structures. As such, a conductive interconnect structure such as interconnect structure97(e.g., a conductive tape) may bridge across gap94to electrically and physically connect frame structure92to backplate90.

Because interconnect structure97may form a non-ohmic contact with frame structure92and/or backplate90, interconnect structure97may cause the generation of spurious signals. Without any victim frequency rejection structures, frame structure92(when excited by spurious signals generated by interconnect structure97) may exhibit standing waves (e.g., standing wave current and voltage distributions) across its entire structure around the periphery of display module89, thereby radiating at the victim frequencies and degrading the performance of victim wireless circuitry. To provide a victim frequency rejection structure, frame structure92may include slot element80that overlaps interconnect structure97. In such a manner, spurious signals generated by interconnect structure97at its non-ohmic contacts may locally excite slot element80(e.g., standing waves are locally exhibited in or are concentrated at region96) instead of across the entire structure of frame structure92, thereby reducing the amplitude of the standing waves. Furthermore, slot element80may have dimensions configured to reject one or more victim frequencies (e.g., to serve as an inefficient radiator at these frequencies by exhibiting reduced or non-peak frequency responses at these frequencies), thereby further reducing the amplitude of the standing waves.

In some illustrative scenarios, an additional victim frequency rejection slot element may be formed in a ground structure connected to frame structure92in which slot element80is formed. In some illustrative scenarios (e.g., considering other device constraints), it may be undesirable to form such a slot element in a display backplate.

FIG.8is a cross-sectional view of an illustrative portion of the display module structures as viewed along line A-A′ inFIG.7. As shown inFIG.8, display14may include display module89. Display module89may include display layers98each implementing one or more of pixel circuitry, touch sensor circuitry, force sensor circuitry, and/or any other desired circuitry for forming active area AA of display14. Display14may include a dielectric cover layer such as display cover layer100that overlaps display module89. Display cover layer100may include plastic, glass, sapphire, ceramic, and/or any other desired dielectric materials. The active area of display module89may emit image light and may receive sensor input (e.g., touch and/or force sensor input) through display cover layer100. Display cover layer100and display14may be mounted to conductive housing structures (structures12W inFIG.1). An inactive area IA of display14may surrounded the active area AA of display14.

Display backplate90may serve as a structural support structure supporting display layers98and as an electrical ground for components in device10(e.g., a reference ground for components implemented by display layers98, an antenna ground for wireless communication circuitry34, etc.). To effectively serve its functions, display backplate90may extend across substantially the entire active area AA of display14.

Frame structure92may run along the periphery (e.g., rectangular periphery as shown inFIG.7) of display cover layer100and serve as a structural support structure, in combination with other intervening structures102such as adhesive layers, polymer layers, etc., for display cover layer100. If desired, frame structure92may have engagement mechanisms that allow display14(e.g., the display assembly) to be mounted to and engage corresponding mechanism in the housing (e.g., corresponding engagement mechanisms on peripheral housing structures12W inFIG.1forming a housing assembly).

Slot element80formed in frame structure92may extend entirely through frame structure92in the z-dimension and may have sides defined by corresponding portions of frame structure92in the x- and y-dimensions. Contacts106may be on one side of slot element80, while contacts108may be on an opposing side of slot element80.

The example ofFIG.8is merely illustrative. In general, any suitable ground structure in device10may include victim frequency rejection structures.FIG.9is cross-sectional side view of device10, showing illustrative conductive electronic device structures that may be used in forming one or more portions of an antenna ground (of one or more of antennas40) in device10.

As shown inFIG.9, peripheral conductive housing structures12W may extend around the lateral periphery of device10(e.g., as measured in the X-Y plane ofFIG.1). Peripheral conductive housing structures12W may extend from rear housing wall12R (e.g., at the rear face of device10) to display14(e.g., at the front face of device10). In other words, peripheral conductive housing structures12W may form conductive sidewalls for device10, a first of which is shown in the cross-sectional side view ofFIG.9(e.g., a given sidewall that runs along an edge of device10and that extends across the width or length of device10).

As shown inFIG.9, rear housing wall12R may be mounted to peripheral conductive housing structures12W (e.g., opposite display14). Rear housing wall12R may include a conductive layer such as conductive support plate112. Conductive support plate112may extend across an entirety of the width of device10(e.g., between the left and right edges of device10as shown inFIG.1). Conductive support plate112may have an edge that is separated from peripheral conductive housing structures12W by dielectric-filled slot114. Slot114may be filled with air, plastic, ceramic, or other dielectric materials. Conductive support plate112may, if desired, provide structural and mechanical support for device10.

If desired, rear housing wall12R may include a dielectric cover layer such as dielectric cover layer110. Dielectric cover layer110may include glass, plastic, sapphire, ceramic, one or more dielectric coatings, or other dielectric materials. Dielectric cover layer110may be layered under conductive support plate112(e.g., conductive support plate112may be coupled to an interior surface of dielectric cover layer110). If desired, dielectric cover layer110may extend across an entirety of the width of device10and/or an entirety of the length of device10. Dielectric cover layer110may overlap slot114.

Conductive housing structures such as conductive support plate112and/or peripheral conductive housing structures12W (e.g., the portion of peripheral conductive housing structures12W opposite conductive support plate112at slot114) may be used to form antenna structures such as antenna ground portions for one or more of antennas40in device10. For example, conductive support plate112may be used to form an antenna ground plane for one or more of antennas40in device10. One or more portions of peripheral conductive housing structures12W may also form corresponding antenna ground portions for one or more of antennas40in device10. In one illustrative configuration, peripheral conductive housing structures12W may include multiple dielectric gaps (e.g., dielectric gaps18ofFIG.1) that divide the peripheral conductive housing structures into multiple segments, some of which may serve as or define antenna resonating elements and some of which may serve as an extension of the antenna ground plane formed by support plate112.

In general, victim frequency rejection structures such as slot element80overlapping a grounding interconnect structure with non-ohmic contacts may be formed in any of these ground structure portions described in connection withFIG.9or other ground structure portions in device10(e.g., conductive traces on printed circuit boards or other substrates, sheet metal, metal foil, other conductive structures associated with display14, other conductive portions of housing12, etc.

FIG.10is a plot showing how the implementation of a victim frequency rejection structure (e.g., slot element80as described in connection withFIGS.5-9) may help reduce standing waves (e.g., peak standing wave current amplitude) at a victim frequency. Curve116plots peak standing wave current amplitude on a ground structure receiving spurious signals from a grounding interconnect structure with non-ohmic contacts without a victim frequency rejection structure. Curve118plots peak standing wave current amplitude on a ground structure having a victim frequency rejection structure (e.g., a slot element in the ground structure with dimension for rejecting a victim frequency F1) when receiving spurious signals containing victim frequency F1.

As shown inFIG.10, at victim frequency F1, peak standing wave current amplitude may exhibit a decrease120from curve116to118. In some illustrative examples (e.g., at victim frequencies of 2.4 GHz and/or 5.5 GHz with the implemented elongated slot element having a length 10 mm), decrease120may be approximately 15 dB. The example ofFIG.10is merely illustrative and, in practice, curves116and118may have other shapes.