Patent Application
20170069954
This relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry.
Electronic devices often include wireless circuitry with antennas. For example, cellular telephones, computers, and other devices often contain antennas for supporting wireless communications.
It can be challenging to form electronic device antenna structures with desired attributes. In some wireless devices, the presence of conductive structures such as conductive housing structures and conductive components can influence antenna performance. Antenna performance may not be satisfactory if the housing structures are not configured properly and interfere with antenna operation or if antennas are undesirably influenced due to conductive structures in nearby components. Device size can also affect performance. It can be difficult to achieve desired performance levels in a compact device, particularly when the compact device has conductive components and housing structures.
It would therefore be desirable to be able to provide improved wireless circuitry for electronic devices such as electronic devices that include conductive structures.
An electronic device may be provided with a housing in which electrical components are mounted. The housing may include a metal portion that serves as ground.
An antenna for the electronic device may be formed from metal traces on an antenna support such as a flexible printed circuit. The flexible printed circuit may be mounted to a speaker box under an inactive edge portion of a display.
The speaker box may have one or more walls formed from metal plates. The metal plates may have portions that are secured within molded plastic speaker box wall structures.
A metal plate in a speaker box may be coupled to a metal clip. The metal plate may be formed in a first speaker box portion and the metal clip may be formed in a second speaker box portion. The metal clip and metal plate may be welded to each other after joining the first and second speaker box portions.
The metal clip may be shorted to a metal stiffener that overlaps a tail portion of the flexible printed circuit. The metal stiffener may serve as a mechanical support for the flexible printed circuit and may form part of a signal path that helps ground the metal plate. A coaxial cable may be soldered or otherwise mounted to contact pads on the flexible printed circuit tail portion.
The metal stiffener may have an opening that is aligned with an opening in the metal clip. A metal fastener such as a screw may pass through the openings to short the metal clip, stiffener, and metal plate to ground.
Electronic devices such as electronic device 10 of
The wireless communications circuitry may include one more antennas. The antennas of the wireless communications circuitry can include loop antennas, inverted-F antennas, strip antennas, planar inverted-F antennas, slot antennas, hybrid antennas that include antenna structures of more than one type, or other suitable antennas.
Electronic device 10 may be a portable electronic device or other suitable electronic device. For example, electronic device 10 may be a laptop computer, a tablet computer, a somewhat smaller device such as a wrist-watch device, pendant device, headphone device, earpiece device, or other wearable or miniature device, a handheld device such as a cellular telephone, a media player, or other small portable device. Device 10 may also be a set-top box, a desktop computer, a display into which a computer or other processing circuitry has been integrated, a display without an integrated computer, or other suitable electronic equipment.
Device 10 may include a housing such as housing 12. Housing 12, which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of these materials. In some situations, parts of housing 12 may be formed from dielectric or other low-conductivity material. In other situations, housing 12 or at least some of the structures that make up housing 12 may be formed from metal elements.
Device 10 may, if desired, have a display such as display 14. Display 14 may 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 planar housing wall.
Display 14 may include pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, or other suitable pixel structures. A display cover layer such as a layer of clear glass or plastic may cover the surface of display 14 or the outermost layer of display 14 may be formed from a color filter layer, thin-film transistor layer, or other display layer. Buttons such as button 24 may pass through openings in the cover layer. The cover layer may also have other openings such as an opening for speaker port 26. Housing 12 may have openings such as openings for audio jack port 50, connector port 52, and speaker port 54.
Housing 12 may include peripheral housing structures such as structures 16. Structures 16 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, structures 16 may be implemented using peripheral housing structures that have a rectangular ring shape with four corresponding edges (as an example). Peripheral structures 16 or part of peripheral structures 16 may serve as a bezel for display 14 (e.g., a cosmetic trim that surrounds all four sides of display 14 and/or that helps hold display 14 to device 10). Peripheral structures 16 may also, if desired, form sidewall structures for device 10 (e.g., by forming a metal band with vertical sidewalls, curved sidewalls, etc.). Peripheral housing structures 16 may be formed from metal such as stainless steel, aluminum, or other suitable materials and may form antenna ground structures, portions of antenna resonating elements (e.g., inverted-F antennas and other antennas for cellular telephone communications, etc.). Other conductive housing structures (e.g., a planar rear wall for device housing 12) may also be formed from metal such as stainless steel, aluminum, or other suitable materials and may form ground structures (e.g., antenna ground).
Display 14 may have an array of pixels that form an active area that displays images for a user of device 10. An inactive border region may run along one or more of the peripheral edges of the active area. 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 midplate) that spans the walls of housing 12 (i.e., a substantially rectangular sheet formed from one or more parts that is welded or otherwise connected between opposing sides of member 16). 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 in device 10, may be located in the center of housing 12 and may extend under the central active area of display 14.
In inactive display regions 22 and 20, openings may be formed within the conductive structures of device 10 (e.g., between peripheral conductive housing structures 16 and opposing conductive ground structures such as conductive housing midplate or rear housing wall structures, a printed circuit board, and conductive electrical components in display 14 and device 10). These openings may be filled with air, plastic, and other dielectrics and may be used in forming antenna resonating elements for one or more antennas in device 10.
If desired, antenna traces on a flexible printed circuit or other carrier may be used to form antenna resonating elements (e.g., resonating elements for a monopole antenna, inverted-F antenna, etc.). A flexible printed circuit may have a flexible substrate formed from a layer of polyimide or other flexible sheet(s) of polymer. The flexible printed circuit on which the antenna resonating element has been formed may be mounted in a location in device 10 that allows the antenna to transmit and receive wireless signals. With one suitable arrangement, one or more wireless local area network antennas may be formed from flexible printed circuit(s) mounted under one or more portions of the display cover layer for display 14 in inactive areas of display 14 such as areas 20 and/or 22. During operation, these antennas may transmit and receive antenna signals that have passed through dielectric portions of device 10 such as the overlapping portions of the display cover layer. If desired, housing 12 may be formed from dielectric and/or may be formed from metal with dielectric antenna windows located over the antennas to permit antenna signals to be transmitted and received by the antennas through the housing.
In general, device 10 may include any suitable number of antennas (e.g., one or more, two or more, three or more, four or more, etc.). The antennas in device 10 may be located at opposing first and second ends of an elongated device housing (e.g., at ends 20 and 22 of device 10 of
In a typical scenario, device 10 may have one or more upper and one or more lower antennas (as an example). An upper antenna may, for example, be formed at the upper end of device 10 in region 22. A lower antenna may, for example, be formed at the lower end of device 10 in region 20. The antennas may be used separately to cover identical communications bands, overlapping communications bands, or separate communications bands. The antennas may be used to implement an antenna diversity scheme or a multiple-input-multiple-output (MIMO) antenna scheme (e.g., a wireless local area network MIMO scheme).
Antennas in device 10 may be used to support any communications bands of interest. For example, device 10 may include antenna structures for supporting local area network communications, voice and data cellular telephone communications, global positioning system (GPS) communications or other satellite navigation system communications, Bluetooth® communications, etc.
A schematic diagram of device 10 is shown in
Control circuitry 28 may be used to run software on device 10, such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, circuitry 28 may be used in implementing communications protocols. Communications protocols that may be implemented using storage and processing circuitry 28 include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol, cellular telephone protocols, multiple-input and multiple-output (MIMO) protocols, antenna diversity protocols, etc.
Control circuitry 28 may be coupled to input-output devices 32. Input-output devices 32 may be used to allow data to be supplied to device 10 and to allow data to be provided from device 10 to external devices. Input-output devices 32 may include user interface devices, data port devices, and other input-output components. For example, input-output devices 32 may include touch screens, displays without touch sensor capabilities, buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, position and orientation sensors (e.g., sensors such as accelerometers, gyroscopes, and compasses), capacitance sensors, proximity sensors (e.g., capacitive proximity sensors, light-based proximity sensors, etc.), fingerprint sensors (e.g., a fingerprint sensor integrated with a button such as button 24 of
To provide antenna structures such as antenna(s) 40 with the ability to cover communications frequencies of interest, antenna(s) 40 may be provided with circuitry such as filter circuitry (e.g., one or more passive filters and/or one or more tunable filter circuits). Discrete components such as capacitors, inductors, and resistors may be incorporated into the filter circuitry. Capacitive structures, inductive structures, and resistive structures may also be formed from patterned metal structures (e.g., part of an antenna). If desired, antenna(s) 40 may be provided with adjustable circuits to tune antennas over communications bands of interest.
Path 92 may include one or more transmission lines. As an example, signal path 92 of
Transmission line 92 may be coupled to antenna feed structures associated with antenna 40. As an example, antenna 40 may be formed from an antenna resonating element trace on a flexible printed circuit (see, e.g., trace 104 of
A speaker such as speaker 106 of
Opening 108 in speaker box 118 may allow sound to pass from interior region 116 to the exterior of device 10 via speaker port 54 (e.g., through one or more openings in housing 12). At the same time, speaker box 118 may serve as a support that holds flexible printed circuit 112 of antenna 40 at a desired distance in dimension Z from underlying ground structures (e.g., metal housing structures under box 118, ground lines in printed circuits that are overlapped by box 118, etc.). Speaker box 118 may have any suitable hollow shape (e.g., a spherical shape, a rectangular box shape, a shape with curved and/or flat portions, etc.). The use of a rectangular box shape for speaker box 118 of
The walls of speaker box 118 may be formed from materials such as plastic and/or metal. Metal walls (e.g., walls of stainless steel, etc.) may be relatively thin for a given strength, and may therefore be used to help reduce the overall thickness of box 118. The use of metal plates to form one or more of the walls of box 18 therefore allows the volume of interior cavity 116 to be increased without increasing the exterior dimensions of box 118.
A cross-sectional side view of speaker box 118 of speaker 106 in an illustrative configuration in which box 118 has an upper metal plate and opposing lower metal plate is shown in
A perspective view of flexible printed circuit 112 is shown in
Stiffener 130 may help structurally support flexible printed circuit tail 112′ and thereby facilitate attachment of coaxial cable 92 to the underside of tail 112′.
Clip 150 may have openings such as opening 160 to receive screws (e.g., to help mechanically and/or electrically couple clip 150 to housing 12 and/or other ground structures). The opening may pass through upper clip portion 156 and parallel lower clip portion 158.
When portions 118-1 and 118-2 are joined, portion 152 of clip 150 will meet portion 120′ of plate 120 along seam (joint) 154. Laser welds, solder, and/or conductive adhesive may be used in coupling clip 150 and plate 120 along seam 154 after portions 118-1 and 118-2 have been assembled.
With this approach, clip 150 is joined to plate 120 after upper and lower mating portions of speaker box 118 have been assembled. By delaying the process of joining clip 150 and plate 120 until after speaker box assembly, residual stresses that might otherwise be imparted to speaker box 118 from clip 140 and plate 120 may be minimized. This helps box 118 to maintain desired acoustic properties such as desired acoustic sealing levels.
A perspective view of speaker 106 is shown in
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.
