PATENT DOCUMENT

Publication Number: US-9705180-B2
Application Number: US-201514825011-A
Country: US
Kind Code: B2

Title: Antenna having flexible feed structure with components

Abstract:
Electronic devices may include antenna structures. The antenna structures may form an antenna having first and second feeds at different locations. Transceiver circuitry for transmitting and receiving radio-frequency antenna signals may be mounted on one end of a printed circuit board. Transmission line structures may be used to convey signals between an opposing end of the printed circuit board and the transceiver circuitry. The printed circuit board may be coupled to an antenna feed structure formed from a flexible printed circuit using solder connections. The flexible printed circuit may have a bend and may be screwed to conductive electronic device housing structures using one or more screws at one or more respective antenna feed terminals. Electrical components such as an amplifier circuit and filter circuitry may be mounted on the flexible printed circuit.

Claims:
What is claimed is: 
     
       1. An electronic device having peripheral edges, comprising:
 a display having a display cover layer; 
 antenna structures that include an inverted-F antenna resonating element that extends along at least a given one of the peripheral edges of the electronic device, wherein the display cover layer has a portion that overlaps the inverted-F antenna resonating element; 
 a flexible printed circuit having transmission line structures for the inverted-F antenna resonating element; and 
 a fastening structure that secures the flexible printed circuit to the antenna structures, wherein the flexible printed circuit has a bend. 
 
     
     
       2. The electronic device defined in  claim 1 , wherein the antenna structures further comprise:
 a signal feed terminal for the inverted-F antenna resonating element, wherein the transmission line structures on the flexible printed circuit are conductively coupled to the signal feed terminal. 
 
     
     
       3. The electronic device defined in  claim 1 , wherein the fastening structure comprises a conductive fastener. 
     
     
       4. The electronic device defined in  claim 1 , wherein the fastening structure comprises a screw. 
     
     
       5. The electronic device defined in  claim 1 , further comprising:
 at least one impedance matching circuit for the antenna structures that is mounted to the flexible printed circuit. 
 
     
     
       6. The electronic device defined in  claim 1 , further comprising:
 conductive housing side walls that extend perpendicular to a planar face of the display cover layer, wherein the flexible printed circuit has a first portion that extends substantially parallel to the conductive housing side walls and a second portion that extends substantially parallel to the planar face of the display cover layer. 
 
     
     
       7. The electronic device defined in  claim 1 , wherein the display further comprises a display module that emits light, the display cover layer has an additional portion, the portion of the display cover layer that overlaps the inverted-F antenna resonating element does not overlap the display module, and the additional portion of the display cover layer does not overlap the inverted-F antenna resonating element. 
     
     
       8. The electronic device defined in  claim 1 , wherein the bend is adjacent to the antenna structures. 
     
     
       9. An electronic device having peripheral edges, comprising:
 a display having a display cover layer; 
 antenna structures that include an inverted-F antenna resonating element that extends along at least a given one of the peripheral edges of the electronic device, wherein the display cover layer has a portion that overlaps the inverted-F antenna resonating element; 
 a flexible printed circuit having transmission line structures for the inverted-F antenna resonating element; 
 a fastening structure that secures the flexible printed circuit to the antenna structures; 
 a rigid printed circuit board coupled to the flexible printed circuit; and 
 radio-frequency transceiver circuitry on the rigid printed circuit board, wherein the transmission line structures are coupled between the radio-frequency transceiver circuitry and the inverted-F antenna resonating element. 
 
     
     
       10. An electronic device having peripheral edges, comprising:
 a display having a display cover layer; 
 antenna structures that include an inverted-F antenna resonating element that extends along at least a given one of the peripheral edges of the electronic device, wherein the display cover layer has a portion that overlaps the inverted-F antenna resonating element; 
 a flexible printed circuit having transmission line structures for the inverted-F antenna resonating element; and 
 a fastening structure that secures the flexible printed circuit to the antenna structures, 
 
       wherein the flexible printed circuit comprises a conductive trace coupled to the transmission line structures and a hole in the conductive trace through which the fastening structure passes while securing the flexible printed circuit to the antenna structures. 
     
     
       11. An electronic device having a periphery, comprising:
 peripheral conductive housing sidewall structures that surround the periphery of the electronic device, wherein the peripheral conductive housing sidewall structures form a portion of an antenna for the electronic device; 
 a display having a display cover layer, wherein a portion of the display cover layer adjacent to the periphery of the electronic device overlaps the peripheral conductive housing sidewall structures; 
 a flexible printed circuit; 
 at least one conductive line on the flexible printed circuit that forms part of an antenna feed for the antenna; and 
 a fastening structure that mates with a hole in the peripheral conductive housing sidewall structures and mechanically secures the flexible printed circuit to the peripheral conductive housing sidewall structures. 
 
     
     
       12. The electronic device defined in  claim 11 , wherein the peripheral conductive housing sidewall structures comprise first and second portions, the portion of the antenna comprises an antenna resonating element for the antenna, the first portion of the peripheral conductive housing sidewall structures comprises the antenna resonating element for the antenna, the second portion of the peripheral conductive housing sidewall structures comprises at least some of a ground plane for the antenna, and the first and second portions are separated by at least one dielectric filled gap. 
     
     
       13. The electronic device defined in  claim 11 , wherein the peripheral conductive housing sidewall structures have a first surface that extends parallel to a face of the display cover layer and a second surface that extends perpendicular to the first surface. 
     
     
       14. The electronic device defined in  claim 13 , wherein the flexible printed circuit has a first portion that extends substantially parallel to the first surface and a second portion that extends substantially parallel to the second surface. 
     
     
       15. An electronic device, comprising:
 a display having a display module that emits light through a display cover layer; 
 peripheral conductive housing sidewall structures that surround the display module and that comprise external surfaces of the electronic device; 
 an antenna, wherein a portion of the peripheral conductive housing sidewall structures form at least a portion of the antenna; and 
 a flexible printed circuit board having traces that form part of a feed structure for the antenna, wherein the flexible printed circuit board comprises a bend adjacent to the peripheral conductive housing sidewall structures. 
 
     
     
       16. The electronic device defined in  claim 15 , wherein the display cover layer has a first portion that overlaps the display module without overlapping the peripheral conductive housing sidewall structures and a second portion that overlaps the peripheral conductive housing sidewall structures and the flexible printed circuit without overlapping the display module. 
     
     
       17. The electronic device defined in  claim 15 , further comprising:
 a fastening structure that affixes the flexible printed circuit board to the peripheral conductive housing sidewall structures. 
 
     
     
       18. The electronic device defined in  claim 17 , wherein the peripheral conductive housing sidewall structures comprise a threaded hole that is configured to receive a threaded portion of the fastening structure. 
     
     
       19. The electronic device defined in  claim 17 , wherein the fastening structure affixes the flexible printed circuit board to the peripheral conductive housing sidewall structures at a first location on the peripheral conductive housing structures, the electronic device further comprising:
 an additional fastening structure that affixes the flexible printed circuit board to the peripheral conductive housing sidewall structures at a second location on the peripheral conductive housing sidewall structures that is different from the first location.

Description:
This application is a continuation of U.S. patent application Ser. No. 14/486,602, filed Sep. 15, 2014, which is a continuation of U.S. patent application Ser. No. 13/435,351, filed Mar. 30, 2012. This application claims the benefit of and claims priority to U.S. patent application Ser. No. 14/486,602, filed Sep. 15, 2014 and U.S. patent application Ser. No. 13/435,351, filed Mar. 30, 2012, which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     This relates generally to electronic devices, and more particularly, to antenna structures for electronic devices with wireless communications circuitry. 
     Electronic devices such as portable computers and cellular telephones are often provided with wireless communications capabilities. For example, electronic devices may use long-range wireless communications circuitry such as cellular telephone circuitry to communicate using cellular telephone bands. Electronic devices may use short-range wireless communications circuitry such as wireless local area network communications circuitry to handle communications with nearby equipment. Electronic devices may also be provided with satellite navigation system receivers and other wireless circuitry. 
     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, it may be desirable to include conductive structures in an electronic device such as metal device housing components. Because conductive components can affect radio-frequency performance, care must be taken when incorporating antennas into an electronic device that includes conductive structures. 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. 
     It would therefore be desirable to be able to provide improved antenna structures for wireless electronic devices. 
     SUMMARY 
     Electronic devices may include antenna structures. The antenna structures may be formed from antenna resonating element and ground structures. The antenna resonating element structures may be formed from conductive portions of an electronic device housing such as peripheral conductive housing structures. The ground structures may include housing structures, printed circuit board traces, and other conductive structures. The ground structures associated with an antenna may be separated from peripheral conductive housing structures or other antenna resonating element structures by a gap. 
     The antenna structures may form an antenna having a single feed or having first and second feeds at different locations. Transceiver circuitry for transmitting and receiving radio-frequency antenna signals may be mounted on a first end of a printed circuit board. Transmission line structures may be used to convey signals between an opposing second end of the printed circuit board and the first end of the printed circuit board. 
     The printed circuit board may be coupled to an antenna feed structure formed from a flexible printed circuit using solder connections. The flexible printed circuit may have a bend. One edge of the flexible printed circuit may be coupled to the printed circuit board using the solder connections or other electrical connections. The other edge of the flexible printed circuit may be attached to the vertical inner surface of a peripheral conductive housing structure or other antenna resonating element structure. The flexible printed circuit may, for example, be screwed to the conductive electronic device housing structures using one or more screws at one or more antenna feed terminals. 
     Electrical components such as an amplifier circuit and filter circuitry may be mounted on the flexible printed circuit. 
     Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment of the present invention. 
         FIG. 2  is a schematic diagram of an illustrative electronic device with wireless communications circuitry in accordance with an embodiment of the present invention. 
         FIG. 3  is a diagram of an illustrative antenna structure in accordance with an embodiment of the present invention. 
         FIG. 4  is a diagram of an illustrative electronic device of the type shown in  FIG. 1  showing how structures in the device may form a ground plane and antenna resonating element structures in accordance with an embodiment of the present invention. 
         FIG. 5  is a diagram showing how device structures of the type shown in  FIG. 4  may be used in forming an antenna with multiple feeds in accordance with an embodiment of the present invention. 
         FIG. 6  is a diagram of an antenna of the type shown in  FIG. 5  with multiple feeds and associated wireless circuitry such as filters and matching circuits in accordance with an embodiment of the present invention. 
         FIG. 7  is a cross-sectional side view of a portion of a device of the type shown in  FIG. 4  showing how an antenna feed may be formed using a flexible printed circuit that spans a gap between a printed circuit board and a peripheral conductive housing structure in accordance with an embodiment of the present invention. 
         FIG. 8  is a perspective view of conductive housing structures that may be used in forming a device of the type shown in  FIG. 1  in accordance with an embodiment of the present invention. 
         FIG. 9  is a top view of an electronic device with antenna structures that may use an antenna feed arrangement of the type shown in  FIG. 7  in accordance with an embodiment of the present invention. 
         FIG. 10  is a perspective view of a portion of a device housing showing how a device with an antenna structure of the type shown in  FIG. 9  may be provided with an antenna feed arrangement of the type shown in  FIG. 7  in accordance with an embodiment of the present invention. 
         FIG. 11  is a top view of an illustrative flexible printed circuit of the type that may be used in forming an antenna feed structure with a low noise amplifier and other electrical components in accordance with an embodiment of the present invention. 
         FIG. 12  is a cross-sectional side view of an electronic device having a feed structure formed from a flexible substrate with attached electrical components such as a low noise amplifier in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices such as electronic device  10  of  FIG. 1  may be provided with wireless communications circuitry. The wireless communications circuitry may be used to support wireless communications in one or more wireless communications bands. The wireless communications circuitry may include one or more antennas. 
     The antennas 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. Conductive structures for the antennas may, if desired, be formed from conductive electronic device structures. The conductive electronic device structures may include conductive housing structures. The housing structures may include a peripheral conductive structure that runs around the periphery of an electronic device. The peripheral conductive structure may be formed from a separate rectangular-ring-shaped member or some or all of the peripheral conductive structure may be formed as an integral portion of a rear housing plate (as examples). The peripheral conductive structure, which may sometimes be referred to as a peripheral conductive member or peripheral housing structures, may serve as a bezel for a planar structure such as a display, may serve as sidewall structures for a device housing, and/or may form other housing structures. Gaps in the peripheral conductive member may be associated with antennas in device  10 . 
     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 cellular telephone, or a media player. Device  10  may also be a television, a set-top box, a desktop computer, a computer monitor into which a computer has been integrated, 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. For example, glass structures, plastic structures, or other dielectric structures may be used to form exterior and interior portions of housing  12 . 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, for example, be a touch screen that incorporates capacitive touch electrodes. Display  14  may include image pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, or other suitable image pixel structures. A cover glass layer may cover the surface of display  14 . Buttons such as button  19  may pass through openings in the cover glass. The cover glass may also have other openings such as an opening for speaker port  26 . 
     Housing  12  may include peripheral conductive portions. For example, housing  12  may include peripheral conductive structures such as peripheral conductive member  16 . Member  16  may run around the periphery of device  10  and display  14 . Member  16  or portions of member  16  may form an integral part of a planar rear housing structure (e.g., a planar rear housing wall) and/or separate housing structures. In configurations in which device  10  and display  14  have a rectangular shape, member  16  may have a rectangular ring shape (as an example). Member  16  or part of member  16  may serve as a bezel for display  14  (e.g., a cosmetic trim that surrounds all four sides of display  14  and/or helps hold display  14  to device  10 ). Member  16  may also, if desired, form sidewall structures for device  10  (e.g., by forming a metal band with vertical sidewalls, by forming sidewalls that extend vertically from a planar rear housing member, etc.). 
     Member  16  may be formed of a conductive material and may therefore sometimes be referred to as a peripheral conductive member, peripheral conductive structures, or conductive housing structures. Member  16  may be formed from a metal such as stainless steel, aluminum, or other suitable materials. One, two, or more than two separate structures may be used in forming member  16 . 
     It is not necessary for member  16  to have a uniform cross-section. For example, the top portion of member  16  may, if desired, have an inwardly protruding lip that helps hold display  14  in place. If desired, the bottom portion of member  16  may also have an enlarged lip (e.g., in the plane of the rear surface of device  10 ). In the example of  FIG. 1 , member  16  has substantially straight vertical sidewalls. This is merely illustrative. The sidewalls of member  16  may be curved or may have any other suitable shape. In some configurations (e.g., when member  16  serves as a bezel for display  14 ), member  16  may run around the lip of housing  12  (i.e., member  16  may cover only the edge of housing  12  that surrounds display  14  and not the rear edge of housing  12  of the sidewalls of housing  12 ). 
     Display  14  may include conductive structures such as an array of capacitive electrodes, conductive lines for addressing pixel elements, driver circuits, etc. Housing  12  may include internal structures such as metal frame members, a planar interior housing member (sometimes referred to as a midplate) that spans the walls of housing  12  (i.e., one or more sheet metal structures that form a substantially rectangular member that is welded or otherwise connected between opposing sides of member  16 ), a planar rear housing wall, printed circuit boards, and other conductive structures. These conductive structures may be located in the center of housing  12  under display  14  (as an example). 
     In regions  22  and  20 , openings (gaps) may be formed within the conductive structures of device  10  (e.g., between peripheral conductive member  16  and opposing conductive structures such as conductive housing structures, a conductive ground plane associated with a printed circuit board, a conductive rear housing wall, conductive components such as a display, and other conductive electrical components in device  10 ). These openings may be filled with air, plastic, and other dielectrics. 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  20  and  22  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, or may otherwise serve as part of antenna structures formed in regions  20  and  22 . 
     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, 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 such locations. The arrangement of  FIG. 1  is merely illustrative. 
     Portions of member  16  may be provided with gap structures. For example, member  16  may be provided with one or more gaps such as gaps  18 , as shown in  FIG. 1 . The gaps 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 member  16  (e.g., the sidewalls of housing  12 ) into one or more peripheral conductive member segments. There may be, for example, two segments of member  16  (e.g., in an arrangement with two gaps), three segments of member  16  (e.g., in an arrangement with three gaps), four segments of member  16  (e.g., in an arrangement with four gaps, etc.). The segments of peripheral conductive member  16  that are formed in this way may form parts of antennas in device  10 . 
     In a typical scenario, device  10  may have upper and 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. 
     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 an illustrative configuration that may be used for electronic device  10  is shown in  FIG. 2 . As shown in  FIG. 2 , electronic device  10  may include storage and processing circuitry  28 . Storage and processing circuitry  28  may include storage such as 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. Processing circuitry in storage and processing circuitry  28  may be used to control the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio codec chips, application specific integrated circuits, etc. 
     Storage and processing 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, storage and processing 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, etc. 
     Circuitry  28  may be configured to implement control algorithms that control the use of antennas in device  10 . For example, circuitry  28  may perform signal quality monitoring operations, sensor monitoring operations, and other data gathering operations and may, in response to the gathered data and information on which communications bands are to be used in device  10 , control which antenna structures within device  10  are being used to receive and process data and/or may adjust one or more switches, tunable elements, or other adjustable circuits in device  10  to adjust antenna performance. As an example, circuitry  28  may control which of two or more antennas is being used to receive incoming radio-frequency signals, may control which of two or more antennas is being used to transmit radio-frequency signals, may control the process of routing incoming data streams over two or more antennas in device  10  in parallel, may tune an antenna to cover a desired communications band, etc. In performing these control operations, circuitry  28  may open and close switches, may turn on and off receivers and transmitters, may adjust impedance matching circuits, may configure switches in radio-frequency circuits that are interposed between radio-frequency transceiver circuitry and antenna structures (e.g., filtering and switching circuits used for impedance matching and signal routing), may adjust switches, tunable circuits, and other adjustable circuit elements that are formed as part of an antenna or that are coupled to an antenna or a signal path associated with an antenna, and may otherwise control and adjust the components of device  10 . 
     Input-output circuitry  30  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 circuitry  30  may include input-output devices  32 . Input-output devices  32  may include touch screens, buttons, joysticks, click wheels, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors, light-emitting diodes and other status indicators, data ports, etc. A user can control the operation of device  10  by supplying commands through input-output devices  32  and may receive status information and other output from device  10  using the output resources of input-output devices  32 . 
     Wireless communications 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, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Wireless communications circuitry  34  may include satellite navigation system receiver circuitry  35  such as Global Positioning System (GPS) receiver circuitry (e.g., for receiving satellite positioning signals at 1575 MHz) or satellite navigation system receiver circuitry associated with other satellite navigation systems. Transceiver circuitry  36  may handle 2.4 GHz and 5 GHz bands for WiFi® (IEEE 802.11) communications and may handle the 2.4 GHz Bluetooth® communications band. Circuitry  34  may use cellular telephone transceiver circuitry  38  for handling wireless communications in cellular telephone bands such as bands in frequency ranges of about 700 MHz to about 2200 MHz or bands at higher or lower frequencies. Wireless communications circuitry  34  can include circuitry for other short-range and long-range wireless links if desired. For example, wireless communications circuitry  34  may include wireless circuitry for receiving radio and television signals, paging circuits, etc. In WiFi® and Bluetooth® links and other short-range wireless links, wireless signals are typically used to convey data over tens or hundreds of feet. In cellular telephone links and other long-range links, wireless signals are typically used to convey data over thousands of feet or miles. 
     Wireless communications circuitry  34  may include one or more antennas  40 . Antennas  40  may be formed using any suitable antenna types. For example, antennas  40  may include antennas with resonating elements that are formed from loop antenna structure, patch antenna structures, inverted-F antenna structures, closed and open slot antenna structures, planar inverted-F antenna structures, helical antenna structures, strip antennas, monopoles, dipoles, hybrids of these designs, etc. Different types of antennas may be used for different bands and combinations of bands. For example, one type of antenna may be used in forming a local wireless link antenna and another type of antenna may be used in forming a remote wireless link. 
     If desired, antennas  40  may include adjustable components so that antennas  40  can be tuned to cover desired communications bands of interest. Each of antennas  40  may have a single antenna feed or may have multiple antenna feeds. For example, an antenna with multiple feeds may have a first antenna feed that is associated with a first set of communications frequencies and a second antenna feed that is associated with a second set of communications frequencies. The use of multiple feeds (and/or adjustable antenna components) may make it possible to reduce antenna size (volume) within device  10  while satisfactorily covering desired communications bands. 
     An illustrative configuration for an antenna of the type that may be used in device  10  is shown in  FIG. 3 . Antenna  40  of  FIG. 3  may have one or more antenna feeds. As shown in  FIG. 3 , antenna  40  may have conductive antenna structures such as antenna resonating element  50  and antenna ground  52 . The conductive structures that form antenna resonating element  50  and antenna ground  52  may be formed from parts of conductive housing structures, from parts of electrical device components in device  10 , from printed circuit board traces (e.g., conductive lines such as conductive paths formed from metal), from strips of conductor such as strips of wire and metal foil, or other conductive materials. 
     Each antenna feed associated with antenna  40  may, if desired, have a distinct location. As shown in  FIG. 3 , antenna  40  may have a first feed such as feed FA at a first location in antenna  40 , a second feed such as feed FB at a second location in antenna  40 , and one or more additional antenna feeds at potentially different respective locations of antenna  40 . 
     Each of the one or more feeds associated with antenna  40  may be coupled to an associated set of conductive signal paths using terminals such as positive antenna feed terminals (+) and ground antenna feed terminals (−). For example, path  54 A may have a positive conductor  58 A that is coupled to a positive antenna feed terminal in feed FA and a ground conductor  56 A that is coupled to a ground antenna feed terminal in feed FA, whereas path  54 B may have a positive conductor  58 B that is coupled to a positive antenna feed terminal in feed FB and a ground conductor  56 B that is coupled to a ground antenna feed terminal in feed FB. Paths such as paths  54 A and  54 B may be implemented using transmission line structures such as coaxial cables, microstrip transmission lines (e.g., microstrip transmission lines on printed circuits), stripline transmission lines (e.g., stripline transmission lines on printed circuits), or other transmission lines or signal paths. Circuits such as impedance matching and filter circuits and other circuitry may be interposed within paths  54 A and  54 B. 
     Paths such as paths  54 A and  54 B may be used to couple antenna feeds for one or more antennas  40  to radio-frequency transceiver circuitry such as receiver (transceiver)  35  and transceivers  36  and/or  38  of  FIG. 2 . Path  54 A may include one or more transmission line segments and may include positive conductor  56 A and ground conductor  58 A. Path  54 B may include one or more transmission line segments and may include positive conductor  56 B and ground conductor  58 B. One or more circuits such as filter circuits, impedance matching circuits, switches, amplifier circuits, and other circuits may be interposed within paths  54 A and  54 B. 
     With one illustrative configuration, a first path such as path  54 A may be coupled between a first radio-frequency transceiver circuit and first antenna feed FA and a second path such as path  54 B may be used to couple a second radio-frequency transceiver circuit to second antenna feed FB. Feeds FA and FB may be used in transmitting and/or receiving radio-frequency antenna signals. The first transceiver may include a radio-frequency receiver and/or a radio-frequency transmitter. The second transceiver may also include a radio-frequency receiver and/or a radio-frequency transmitter. 
     The first transceiver may, as an example, be a transceiver such as a satellite navigation system receiver and the second transceiver may, as an example, be a transceiver such as a cellular telephone transceiver (having a cellular telephone transmitter and a cellular telephone receiver). As another example, the first transceiver may have a transmitter and/or a receiver that operate at frequencies associated with a first communications band (e.g., a first cellular or wireless local area network band) and the second transceiver may have a transmitter and/or a receiver that operate at frequencies associated with a second communications band (e.g., a second cellular or wireless local area network band). Other types of configurations may be used, if desired. The transceivers may be implemented using separate integrated circuits or may be integrated into a common integrated circuit (as examples). One or more associated additional integrated circuits (e.g., one or more baseband processor integrated circuits) may be used to provide the transceiver circuitry with data to be transmitted by antenna  40  and may be used to receive and process data that has been received by antenna  40 . 
     Filter circuitry, impedance matching circuitry, switches, amplifiers, and other electrical components may be interposed in paths such as paths  54 A and  54 B. For example, a first filter may be interposed in path  54 A between feed FA and a first transceiver, so that signals that are transmitted and/or received using antenna feed FA are filtered by the first filter. A second filter may likewise be interposed in path  54 B, so that signals that are transmitted and/or received using antenna feed FB are filtered by the second filter. The filters may be adjustable or fixed. In fixed filter configurations, the transmittance of the filters as a function of signal frequency is fixed. In adjustable filter configurations, adjustable components may be placed in different states to adjust the transmittance characteristics of the filters. 
     If desired, fixed and/or adjustable impedance matching circuits (e.g., circuitry for impedance matching a transmission line to antenna  40  or other wireless circuitry) may be included in paths  54 A and  54 B (e.g., as part of filters or as separate circuits). In a multi-feed antenna, the first and second filters may be configured so that the antenna feeds in the antenna may operate satisfactorily, even in a configuration in which multiple feeds are coupled to antenna  40  simultaneously. 
     A top interior view of device  10  in a configuration in which device  10  has a peripheral conductive structure such as peripheral conductive housing member  16  of  FIG. 1  with one or more gaps  18  is shown in  FIG. 4 . As shown in  FIG. 4 , device  10  may have an antenna ground plane such as antenna ground plane  52 . Ground plane  52  may be formed from traces on printed circuit boards (e.g., rigid printed circuit boards and flexible printed circuit boards), from conductive planar support structures in the interior of device  10 , from conductive structures that form exterior parts of housing  12  (e.g., some or all of a conductive rear housing wall structure), from conductive structures that are part of one or more electrical components in device  10  (e.g., parts of connectors, switches, cameras, speakers, microphones, displays, buttons, etc.), or other conductive device structures. Gaps such as gaps  82  may be filled with air, plastic, or other dielectric. 
     One or more segments of peripheral conductive member  16  may serve as antenna resonating elements such as antenna resonating element  50  of  FIG. 3 . For example, the uppermost segment of peripheral conductive member  16  in region  22  may serve as an antenna resonating element for an antenna in device  10 . The conductive materials of peripheral conductive member  16 , the conductive materials of ground plane  52 , and dielectric openings (gaps)  82  (and gaps  18 ) may be used in forming one or more antennas in device  10  such as an upper antenna in region  22  and a lower antenna in region  20 . Antennas in regions  20  and  22  may each have a single feed or multiple feeds. 
     Using a device configuration of the type shown in  FIG. 5 , a dual-feed antenna for device  10  may be implemented (e.g., a dual-feed inverted-F antenna). Segment  16 ′ of the peripheral conductive member (see, e.g., peripheral conductive structures  16  of  FIG. 4 ) may form antenna resonating element  50 . Ground plane  52  may be separated from antenna resonating element  50  by gap  82 . Gaps  18  may be formed at either end of segment  16 ′ and may have associated parasitic capacitances. Conductive path  84  may form a short circuit path between antenna resonating element  50  (i.e., segment  16 ′) and ground  52 . First antenna feed FA and second antenna feed FB may be located at different locations along the length of antenna resonating element  50 . 
     As shown in  FIG. 6 , it may be desirable to provide each of the feeds of antenna  40  with filter circuitry and impedance matching circuitry. In a configuration of the type shown in  FIG. 6 , antenna resonating element  50  may be formed from a segment of peripheral conductive member  16  (e.g., segment  16 ′ of  FIG. 5 ). Antenna ground  52  may be formed from ground plane structures such as ground plane structure  52  of  FIG. 5 . Antenna  40  of  FIG. 6  may be, for example, an upper antenna in region  22  of device  10  (e.g., an inverted-F antenna). Device  10  may also have additional antennas such as antenna  40 ′ (e.g., an antenna formed in lower portion  20  of device  10 , as shown in  FIG. 4 ). 
     In the illustrative example of  FIG. 6 , satellite navigation receiver  35  (e.g., a Global Positioning System receiver or a receiver associated with another satellite navigation system or other type of transceiver) may serve as a first transceiver for device  10 , whereas cellular telephone transceiver circuitry  38  (e.g., a cellular telephone transmitter and a cellular telephone receiver or another type of transceiver) may serve as a second transceiver for device  10 . If desired, other types of transceiver circuitry may be used in device  10 . The example of  FIG. 6  is merely illustrative. 
     As shown in  FIG. 6 , receiver  35  may be coupled to antenna  40  at first antenna feed FA and transceiver  38  may be coupled to antenna  40  at second antenna feed FB. 
     Incoming signals for receiver  35  may be received through band-pass filter  64 A, optional impedance matching circuits such as matching circuits M 1  and M 4 , and low noise amplifier  86 . The signals received from feed FA may be conveyed through components such as matching filter M 1 , band-pass filter  64 A, matching circuit M 4 , and low noise amplifier  86  using transmission lines paths such as transmission line path  54 A. Additional components may be interposed in transmission line path  54 A, if desired. 
     Signals associated with transmit and receive operations for cellular transceiver circuitry  38  may be handled using notch filter  64 B, optional impedance matching circuits such as matching circuits M 2  and M 3 , antenna selection switch  88 , and circuitry  90 . Antenna selection switch  88  may have a first state in which antenna  40  is coupled to transceiver  38  and a second state in which antenna  40 ′ is coupled to transceiver  38  (as an example). If desired, switch  88  may be a cross-bar switch that couples either antenna  40  or antenna  40 ′ to transceiver  38  while coupling the remaining antenna to another transceiver. 
     Circuitry  90  may include filters (e.g., duplexers, diplexers, etc.), power amplifier circuitry for amplifying transmitted signals, band selection switches, and other components. The components used in transmitting and receiving signals with feed FB may be conveyed through components such as matching filter M 2 , notch filter  64 B, matching circuit M 3 , and circuitry  90  using transmission lines paths such as transmission line path  54 B (see, e.g.,  FIGS. 3 and 9 ). Additional components may be interposed in transmission line path  54 B, if desired. 
       FIG. 7  is a cross-sectional side view of a portion of device  10  in the vicinity of upper region  22 . Housing structures  12  may include upper housing structure  12 A (e.g., a display cover layer such as a layer of cover glass, transparent plastic, or other clear material). Housing structure  12 A may cover display module  14 . Gap  82  may separate the edge of display  14  and peripheral conductive housing structure  16 . 
     Antenna  40  may include an antenna resonating element formed from a segment of peripheral conductive structures  16  and a ground such as ground plane  52 . Ground plane  52  may include conductive housing structures (e.g., sheet metal structures), electrical components, conductive traces on printed circuit boards, and other conductive materials. 
     As shown in  FIG. 7 , device  10  may include a printed circuit board such as printed circuit board  102 . Printed circuit board  102  may be used to mount electrical components  122  such as integrated circuits and other circuits. Conductive traces  104  may form interconnects that interconnect electrical components  122  with each other. The interconnects in board  102  may also form signal paths for antenna signals associated with antenna  40 . As shown in  FIG. 7 , for example, traces  104  on printed circuit board  102  may be electrically connected to traces  108  on printed circuit  110  using solder connections such as solder connection  106 . If desired, a connector (e.g., a board-to-board connector or other suitable connector) may be used in connecting traces  104  on printed circuit board  102  and traces  108  of printed circuit  110 . Welds, conductive adhesive, and other electrical connections may also be used, if desired. The use of solder connections in the configuration of  FIG. 7  is merely illustrative. 
     Printed circuit board  102  may be, for example, a rigid printed circuit board such as a printed circuit board formed from fiberglass-filled epoxy (e.g., FR4), a flexible printed circuit, a plastic substrate, a substrate formed from other suitable dielectrics, or other suitable substrate. Traces and components on printed circuit board  102  may form part of antenna ground  52 . 
     Printed circuit  110  may be a flexible printed circuit (“flex circuit”) formed from a flexible sheet of polymer such as a layer of polyimide or other suitable dielectric substrate. Printed circuit  110  may, as an example, have a thickness of less than 0.5 mm, less than 0.2 mm, or 0.1 mm (as examples). Components  112  may be mounted to printed circuit  110 . Components  112  may include radio-frequency filter circuitry, switching circuitry, tunable and/or fixed impedance matching circuitry, amplifier circuitry, transceiver circuitry, and other circuitry. Traces  108  in printed circuit  110  may be used to interconnect components  112 . 
     Traces  104  and  108  may include conductive structures for forming transmission line paths (e.g., paths  54 A and  54 B of  FIG. 3 ). For example, traces  104  and  108  may be used to form microstrip transmission lines or other transmission line structures. Parts of transmission lines  54 A and  54 B may also be formed using other transmission line structures (e.g., segments of coaxial cable transmission lines, segments of flexible printed circuit microstrip transmission line structures or other transmission lines formed from flex circuit substrates). 
     Printed circuit board  110  may be used to form antenna feed structures for the antenna feed for antenna  40  (e.g., feed FA and/or feed FB). For example, conductive traces  108  may be used to form an antenna signal path such as positive antenna feed signal path  58 A of  FIG. 3  that bridges gap  82  and may be used in forming ground structures such as ground path  56 A of  FIG. 3 . Traces  108  may include surface traces such as traces  120  for coupling traces  108  to peripheral conductive housing structure  16  via metal screw  114  or other conductive fastener. 
     Screw  114  may have a head that is used to screw a portion of flexible printed circuit  110  into place against inner surface  140  of peripheral conductive housing structures  16 . Screw  114  may also have a threaded shaft such as shaft  118  that screws into threads in threaded hole  116  in peripheral conductive housing structure  16 . The conductive structures in the vicinity of screw  114  may form positive antenna feed terminal + for antenna feed FA. In antenna configurations with multiple feeds, additional screws may form additional positive antenna feed terminals. For example, in a configuration in which antenna  40  has a second antenna feed FB, an additional screw (screw  114 ′ of  FIG. 9 ) may be used in forming positive antenna feed terminal + for feed FB. Traces  108  may be used in routing antenna signals to the terminals of both feed FA and feed FB. 
     If desired, traces  108  may be coupled to peripheral conductive housing structure  16  using welds, solder, conductive adhesive, fasteners other than screws, or other suitable attachment mechanisms. The configuration of  FIG. 7  in which conductive traces  108  are coupled to peripheral conductive housing structures  16  using screw  114  is merely illustrative. 
     Because flexible printed circuit  110  has a substrate formed from a sheet of flexible polymer, flexible printed circuit  110  may be bent to form bend  142 . In the vicinity of solder  106 , where flexible printed circuit  110  is connected to printed circuit  102 , flexible printed circuit  110  and printed circuit  102  may lie parallel to the X-Y plane. In the vicinity of screw  114 , flexible printed circuit  110  may lie in the X-Z plane, perpendicular to the X-Y plane and parallel to inner surface  140  of peripheral conductive housing structure  16 . 
       FIG. 8  is a perspective view of housing  12  showing how peripheral conductive housing structure  16  may be formed from segments such as segments  16 A,  16 B,  16 C, and  16 D that are separated by gaps  18 . Holes  116  and  116 ′ may be used to form threaded openings for screws  114  and  114 ′ for the positive antenna feed terminals of feeds FA and FB, respectively. Segments  16 A and  16 C may be formed from U-shaped bands of metal (e.g., stainless steel, aluminum or other suitable conductive material). Segments  16 B and  16 D may form integral sidewall portions of planar rear housing member  12 R of housing  12  and may be formed from a conductive material such as metal (e.g., stainless steel, aluminum, etc.). Other types of configurations for housing  12  may be used in device  10  if desired. The example of  FIG. 8  is merely illustrative. 
       FIG. 9  is a top view of device  10  showing how flexible printed circuit  110  or other dielectric substrate (e.g., a rigid printed circuit board, plastic support structure, etc.) may be used in forming antenna feeds FA and FB in upper region  22  of housing  12 . As shown in  FIG. 9 , components  122  may be mounted on printed circuit board  102 . Components  122  may include control circuitry such as storage and processing circuitry  28  of  FIG. 2  and input-output circuitry  30  of  FIG. 2  (e.g., memory chips, processor chips, application-specific integrated circuits, radio-frequency transceiver circuitry, etc.). 
     Printed circuit board  102  may have an elongated shape with edges that run parallel to the longer edges of elongated device housing  12  of device  10  and may have first and second opposing ends  124  and  144 . Wireless communications circuitry  34  such as cellular telephone transceiver circuitry  38 , satellite navigation system receiver circuitry  35 , and additional radio-frequency transceiver circuitry such as transceiver circuitry  36  may be mounted on board  102 . For example, one or more transceiver integrated circuits may be mounted at end  124  of board  102 . 
     Transmission lines such as transmission lines  126  and  128  may be used to route radio-frequency signals between transceiver circuitry in end region  124  and the antenna feed structures formed from printed circuit  110 . Transmission lines  126  may include microstrip transmission lines, stripline transmission lines, coaxial cable transmission line, transmission lines formed from thin strips of flexible printed circuit substrate (e.g., microstrip transmission lines, stripline transmission lines, etc.), or other transmission lines. Traces  104  ( FIG. 7 ) may be used to couple transceiver circuitry in region  124  to radio-frequency connectors such as connectors  130  and  134 . At end  144  of printed circuit board  102 , traces  104  may be coupled between radio-frequency connectors  132  and  136  and traces  108  on printed circuit  110  (e.g., via solder connections  106  formed using hot bar soldering techniques or other suitable connections). 
     Transmission line  126  may be coupled between connector  130  and connector  132 . Transmission line  128  may be coupled between connector  134  and connector  136 . Transmission line  126  may be used to route signals between a first transceiver in region  124  and antenna feed FA. Transmission line  128  may be used to route signals between a second transceiver in region  124  and antenna feed FB. Feed FA may have a screw such as screw  114  for coupling an antenna signal line formed from traces  108  on printed circuit  110  to peripheral conductive housing structure  16  and thereby forming a positive antenna feed terminal + for feed FA. Feed FB may have a screw such as screw  114 ′ for coupling another antenna signal lines formed from traces  108  on printed circuit  110  to peripheral conductive housing structures  16  and thereby forming a positive antenna feed terminal + for feed FB. Printed circuit  110  may be sufficiently flexible to flex along bend axis  146 . One or more openings such as opening  148  that overlap with bend axis  146  may be provided in printed circuit  110  to facilitate bending. 
       FIG. 10  is a perspective view of flexible printed circuit  110  of  FIG. 9 , showing how flexible printed circuit  110  may be used to form antenna feed structures for antenna feeds FA and FB in antenna  40 . As shown in  FIG. 10 , flexible printed circuit  110  may have one or more openings such as opening  148 . Opening  148  may be configured to overlap bend axis  146 . By removing the polymer material of opening  148  from flexible printed circuit  110  along axis  146 , the flexibility of flexible printed circuit  110  may be enhanced. This may help flexible printed circuit  110  bend along axis  146  to form bend  142 . 
     Solder connections such as solder connection  106  of  FIG. 10  may be used to interconnect the conductive signal paths in printed circuit board  102  (e.g., the positive and ground paths such as paths  58 A and  56 A of path  54 A and paths  58 B and  56 B of path  54 B of  FIG. 3 ) to corresponding signal lines in printed circuit board  110  (e.g., traces  108 ). The positive signal line for each feed may extend across gap  82 , as shown by lines  150  and  152  of  FIG. 6 . Ground antenna signal traces, positive antenna signal traces, and power supply lines (positive and ground) may also be provided on flexible printed circuit  110  to couple components  112  to printed circuit board  102 . 
     A top view of illustrative antenna feed structures of the type that may be formed using printed circuit board  110  is shown in  FIG. 11 . As shown in  FIG. 11 , printed circuit board  110  may have opening such as screw hole openings  160  and  160 ′. When mounted in device  10 , the shaft of screw  114  for feed FA may pass through opening  160  until the head of screw  114  bears against conductive traces  120  to short conductive traces  120  for positive antenna signal line  150  and positive antenna feed terminal + of feed FA to peripheral conductive housing structure  16 . The shaft of screw  114 ′ for feed FB may pass through opening  160 ′ to short conductive traces  120 ′ for positive antenna signal line  152  and positive antenna feed terminal + of feed FB to peripheral conductive housing structure  16 . 
     Electrical components  112  may be mounted to flexible printed circuit substrate  110  in region  112 R. For example, components such as matching circuits M 1 , M 2 , M 3 , and/or M 4 , band pass filter  64 A, and low noise amplifier  86  of  FIG. 6  and/or other electrical components may be mounted on flexible printed circuit  110  in region  112 R. 
     By mounting low noise amplifier  86  near end  144  of printed circuit board  102  adjacent to feed FA rather than at end  124  of printed circuit board  102  near the radio-frequency transceivers at end  124 , performance can be enhanced for receiver  35 . This is because incoming antenna signals from feed FA will be amplified by low noise amplifier  86  before being subjected to losses due to the presence of connector  132 , transmission line  126  (e.g., a transmission line having a length of 2-20 cm, more than 2 cm, about 4-15 cm, less than 10 cm, etc.), and connector  130 . Incurring attenuation due to the presence of the signal path ( 54 A) through connector  132 , transmission line structure  126 , and connector  130  only after antenna signals have been amplified by low noise amplifier  86  can help enhance the signal-to-noise ratio of the received signal that is presented to the input of receiver at end  124  of printed circuit  144  (e.g., receiver  35 ). 
     In general, the antenna feed structure formed from flexible printed circuit  110  may include any suitable number of low noise amplifiers (LNAs) for amplifying incoming antenna signals. In the configuration of  FIG. 9 , feed FA may, for example, be provided with a low noise amplifier (i.e., low noise amplifier  86  of  FIG. 6 ) and associated filter and matching circuitry (e.g., band pass filter  64 A of  FIG. 6 ) that are mounted on printed circuit  110 . One or more of the components associated with feed FB such as matching networks M 2  and M 3 , filter  64 B, antenna selection switch  88 , and/or filters  90  may also be mounted on flexible printed circuit  110 , if desired. Electrical components that are not mounted on printed circuit  110  may be mounted on printed circuit board  102  upstream or downstream of transmission line  126  and  128 . 
     Pads P 1 , P 2 , P 3 , P 4 , P 5 , and P 6  may be coupled to traces in printed circuit  110  (e.g., traces  108  of  FIG. 7 ) and, via solder connections  106 , may be coupled to respective traces  104  in printed circuit board  102 . Traces  108  may include positive and ground antenna signal traces for routing radio-frequency signals for feeds FA and FB and traces for routing positive and ground power supply voltages (e.g., for powering circuitry such as low noise amplifier  86 , etc.). With one suitable arrangement, pad P 1  may be coupled to a trace that forms positive antenna signal path  152  for feed FB. Pads P 2 , P 3 , and P 5  may be coupled to ground traces. Pad P 4  may be coupled to a trace that forms a positive antenna signal path. This path may start at conductor  120  of antenna feed FA, may pass through path  150  of  FIG. 11 , band pass filter  64 A, and low noise amplifier  86 , and may terminate at pad P 4 . Pad P 6  may be used to supply power (e.g., a positive power supply voltage or other suitable power supply signal) to low noise amplifier  86  and other circuitry on printed circuit  110 . 
     A cross-sectional side view of device  10  showing how printed circuit  110  may be coupled to printed circuit  102  using solder connections  106  (e.g., solder connections formed using hot bar soldering techniques) is shown in  FIG. 12 . 
     The foregoing is merely illustrative of the principles of this invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention.

Metadata:
Filing Date: 20150812
Publication Date: 20170711
Grant Date: 20170711
Priority Date: 20120330
Inventors: DARNELL DEAN F.
NOELLERT WILLIAM J.
PASCOLINI MATTIA
Assignee: APPLE INC
CPC Classifications: [{"code": "H05K1/028", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/48", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K1/181", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/045", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/045", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K1/028", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K1/181", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/48", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K1/189", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 47833426