PATENT DOCUMENT

Publication Number: US-8269674-B2
Application Number: US-33749908-A
Country: US
Kind Code: B2

Title: Electronic device antenna

Abstract:
Antennas for electronic devices such as portable computers are provided. An antenna may have a dipole structure in which one antenna element serves as a matching element and another antenna element serves as a radiating element. The antenna elements may be mounted on a substrate. The substrate may be mounted on a support structure that is attached to a grounding plate. The grounding plate may be grounded to a conductive housing portion of a portable computer. The antenna may be mounted within the conductive housing in the vicinity of an opening in the housing. The opening may be a slot opening that is used to accommodate optical disks or other storage media. Radio-frequency signals for the antenna may pass through the opening.

Claims:
1. An electronic device, comprising:
 a conductive housing having a media drive opening; and 
 an antenna mounted to the conductive housing and located within an interior portion of the conductive housing adjacent to the media drive opening, so that radio-frequency antenna signals for the antenna pass through the opening. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the electronic device is a portable computer and wherein the conductive housing comprises a metal portable computer housing. 
     
     
       3. The electronic device defined in  claim 2  further comprising an optical disk drive, wherein the media drive opening comprises an optical disk drive slot that accommodates optical disks. 
     
     
       4. The electronic device defined in  claim 3  wherein the antenna comprises a dipole antenna. 
     
     
       5. The electronic device defined in  claim 4  wherein the dipole antenna comprises first and second conductive traces aligned along a common longitudinal axis on a printed circuit board substrate. 
     
     
       6. The electronic device defined in  claim 5  further comprising an unbalanced transmission line that feeds the first and second conductive traces so that the first conductive trace serves as an impedance matching element and the second conductive trace serves as a radiating element for the antenna. 
     
     
       7. The electronic device defined in  claim 1  wherein the antenna comprises a dipole antenna. 
     
     
       8. The electronic device defined in  claim 7  wherein the dipole antenna comprises first and second conductive traces aligned along a common longitudinal axis. 
     
     
       9. The electronic device defined in  claim 8  further comprising an unbalanced transmission line that feeds the first and second conductive traces so that the first conductive trace serves as an impedance matching element and the second conductive trace serves as a radiating element for the antenna. 
     
     
       10. The electronic device defined in  claim 9  wherein the unbalanced transmission line comprises a coaxial cable. 
     
     
       11. The electronic device defined in  claim 10  further comprising a dielectric substrate, a dielectric mounting structure, and a grounding plate, wherein the first and second conductive traces are formed on the dielectric substrate, wherein the dielectric substrate is attached to the dielectric mounting structure, wherein the coaxial cable is grounded to the grounding plate, and wherein the grounding plate is grounded to the conductive housing. 
     
     
       12. The electronic device defined in  claim 11  wherein the dielectric mounting structure and the grounding plate comprises screw holes and wherein the electronic device further comprises screws that pass through the screw holes to screw the antenna and grounding plate to the conductive housing. 
     
     
       13. A portable computer, comprising:
 an optical disk drive; 
 a metal portable computer base unit housing having an optical disk drive slot through which optical disks are loaded into the optical disk drive; and 
 a dipole antenna mounted to and within the metal case, wherein the dipole antenna is operable to transmit and receive radio-frequency antenna signals through the optical disk drive slot. 
 
     
     
       14. The portable computer defined in  claim 13  wherein the dipole antenna has first and second antenna elements and wherein the dipole antenna is configured so that the first antenna element serves as an impedance matching element and so that the second antenna element serves as a radiating element for the antenna. 
     
     
       15. The portable computer defined in  claim 14  further comprising:
 a radio-frequency transceiver that operates at 2.4 GHz; and 
 a coaxial cable that is connected between the radio-frequency transceiver and the dipole antenna, so that the dipole antenna transmits and receives radio-frequency antenna signals at 2.4 GHz through the optical disk drive slot. 
 
     
     
       16. The portable computer defined in  claim 13  further comprising:
 a radio-frequency transceiver; and 
 a coaxial cable that is connected between the radio-frequency transceiver and the dipole antenna, so that the dipole antenna transmits and receives radio-frequency antenna signals through the optical disk drive slot. 
 
     
     
       17. The portable computer defined in  claim 13  further comprising a printed circuit board, wherein the first and second antenna elements comprise conductive traces on the printed circuit board, wherein the first and second antenna elements are substantially rectangular in shape and are aligned along a common longitudinal axis, and wherein the antenna is mounted within the metal personal computer main unit housing so that the longitudinal axis is parallel to the slot.

Description:
BACKGROUND 
     This invention relates to electronic devices and, more particularly, to antennas for electronic devices such as portable computers. 
     Portable computers often use wireless communications circuitry. For example, wireless communications circuitry may be used to communicate with local area networks and remote base stations. 
     Wireless computer communications systems use antennas. It can be difficult to design antennas that perform satisfactorily in portable computers. To conserve battery power, it is generally desirable to create efficient antennas. At the same time, optimum antenna efficiency can be difficult to obtain, because portable computer designs restrict the possible locations for implementing the antennas and require that the antennas be constructed as small light-weight structures. For example, it can be difficult to implement efficient antennas in portable computers that contain conductive housing structures, because the conductive housing structures can block radio-frequency signals and thereby reduce the effectiveness of the antennas. 
     It would therefore be desirable to be able to provide improved antenna arrangements for electronic devices such as portable computers. 
     SUMMARY 
     An antenna for an electronic device such as a portable computer is provided. The antenna may use a dipole design having first and second antenna elements. The electronic device may have a conductive housing having an opening such as an optical disk drive slot or other media drive opening. The antenna may be mounted within the conductive housing in the vicinity of conductive housing walls and the opening. 
     An unbalanced transmission line such as a coaxial cable may be used to feed the antenna. An outer ground conductor from the coaxial cable may feed the first antenna element and a center connector from the coaxial cable may feed the second antenna element. 
     The first antenna element may serve as an impedance matching element. The second antenna element may serve as a radiating element. During operation, radio-frequency signals may pass between the antenna and external equipment through the slot in the conductive housing wall. 
     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 such as a portable computer in which an antenna may be implemented in accordance with an embodiment of the present invention. 
         FIG. 2  is a cross-sectional side view of an illustrative electronic device such as a portable computer in the vicinity of a device housing portion that has a slot and an antenna in accordance with an embodiment of the present invention. 
         FIG. 3  is a perspective of an illustrative antenna that may be used in an electronic device such as a portable computer in accordance with an embodiment of the present invention. 
         FIG. 4  is a schematic diagram showing how part of a dipole antenna of the type shown in  FIG. 3  may operate as an inverted-F antenna in accordance with an embodiment of the present invention. 
         FIG. 5  is a top view showing how an antenna of the type shown in  FIG. 3  may be mounted in an electronic device such as a portable computer in accordance with an embodiment of the present invention. 
         FIG. 6  is a perspective view of an illustrative antenna in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention relates to antenna structures for electronic devices. The antennas may be used to convey wireless signals for suitable communications links. For example, an electronic device antenna may be used to handle communications for a short-range link such as an IEEE 802.11 link (sometimes referred to as WiFi®) or a Bluetooth® link. An electronic device antenna may also handle communications for long-range links such as cellular telephone voice and data links. 
     Antennas such as these may be used in various electronic devices. For example, an antenna may be used in an electronic device such as a handheld computer, a miniature or wearable device, a portable computer, a desktop computer, a router, an access point, a backup storage device with wireless communications capabilities, a mobile telephone, a music player, a remote control, a global positioning system device, devices that combine the functions of one or more of these devices and other suitable devices, or any other electronic device. With one suitable arrangement, which is sometimes described herein as an example, the electronic devices in which the antennas are provided may be portable computers such as laptop (notebook) computers. This is, however, merely illustrative. Antennas may, in general, be provided in any suitable electronic device. 
     An illustrative electronic device such as a portable computer in which an antenna may be provided is shown in  FIG. 1 . As shown in  FIG. 1 , portable computer  10  may have a housing  12 . Housing  12 , which is sometimes referred to as a case, may be formed from one or more individual structures. For example, housing  12  may have a main structural support member that is formed from a solid block of machined aluminum or other suitable metal. Multipart housings may be used in which two or more individual housing structures are combined to form housing  12 . The structures in housing  12  may include internal frame members, external coverings such as sheets of metal, etc. Housing  12  and its associated components may, in general, be formed from any suitable materials such as such as plastic, ceramics, metal, glass, etc. An advantage of forming housing  12  at least partly from metal is that metal is durable and attractive in appearance. Metals such as aluminum may be anodized to form an insulating oxide coating. 
     Case  12  may have an upper portion  26  and a lower portion  28 . Lower portion  28  may be referred to as the base unit housing or main unit of computer  10  and may contain components such as a hard disk drive, battery, and main logic board. Upper portion  26 , which is sometimes referred to as a cover or lid, may rotate relative to lower portion  28  about rotational axis  16 . Portion  18  of computer  10  may contain a hinge and associated clutch structures and may sometimes be referred to as a clutch barrel. 
     Lower housing portion  28  may have an opening such as slot  22  through which optical disks may be loaded into an optical disk drive. Lower housing portion  28  may also have touchpad  24 , keys  20 , and other input-output components. Touch pad  24  may include a touch sensitive surface that allows a user of computer  10  to control computer  10  using touch-based commands (gestures). A portion of touchpad  24  may be depressed by the user when the user desires to “click” on a displayed item on screen  14 . If desired, additional components may be mounted to upper and lower housing portions  26  and  28 . For example, upper and lower housing portions  26  and  28  may have ports to which cables can be connected (e.g., universal serial bus ports, an Ethernet port, a Firewire port, audio jacks, card slots, etc.). Buttons and other controls may also be mounted to housing  12 . 
     If desired, upper and lower housing portions  26  and  28  may have transparent windows through which light may be emitted from light-emitting diodes. Openings such as perforated speaker openings  30  may also be formed in the surface of housing  12  to allow sound to pass through the walls of the housing. 
     A display such as display  14  may be mounted within upper housing portion  26 . Display  14  may be, for example, a liquid crystal display (LCD), organic light emitting diode (OLED) display, or plasma display (as examples). A glass panel may be mounted in front of display  14 . The glass panel may help add structural integrity to computer  10 . For example, the glass panel may make upper housing portion  26  more rigid and may protect display  14  from damage due to contact with keys or other structures. 
     A cross-sectional view of a portion of lower housing portion  28  of housing  12  in the vicinity of slot  22  is shown in  FIG. 2 . As shown in  FIG. 2 , storage media such as optical disk  32  may be inserted into computer  10  through slot  22 . A disk drive  38  (schematically depicted as base unit  36 , rotating spindle  34 , and metal drive housing  39  in  FIG. 2 ) may be used to access data that is stored on optical drive  32 . Data may also be written to drive  32  using optical disk drive  38 . 
     To allow insertion of disk  32  into the cavity associated with the disk drive, the vertical and horizontal dimensions of slot  22  may be constructed to be larger than the corresponding dimensions of an optical disk (e.g., a CD or DVD). As shown in  FIG. 2 , for example, slot height H may be larger than the thickness of disk  32  (e.g., more than 1-5 mm). Similarly, the width W of slot  22  may be larger than the diameter of disk  32  (e.g., more than 12-14 cm). Computer  10  may, if desired, have other openings. For example, computer  10  may have openings such as slot  22  that receive other types of storage media or accessories. In general, these openings may have any suitable shape (e.g., rectangular, circular, polygonal, etc.). The use of slots that are generally rectangular in shape such as slot  22  of  FIGS. 1 and 2  is merely illustrative. 
     Particularly in computers with conductive housings, the presence of an opening such as slot  22  may be used to provide a relatively unobstructed radio-frequency signal passageway between the interior and exterior of the housing. Conductive housing structures such as the metal wall structures that surround slot  22  may partially or fully block radio-frequency signals. This can make it difficult or impossible to locate an antenna directly behind such structures in the absence of slot  22 . 
     In configurations in which slot  22  is available, slot  22  may be used to allow signals to pass between the interior and exterior of computer  10  without being blocked by a conductive housing wall. In particular, an antenna such as antenna  40  may be mounted in the interior or housing  12  in the vicinity of slot  22 . In the  FIG. 2  example, antenna  40  has been mounted to interior surface  44  of the wall of housing portion  28 . This is merely illustrative. Antenna  40  may be mounted at any suitable location within housing  12 , provided that the placement of antenna  40  does not prevent the use of drive  38 . Metal drive housing  39  may help to isolate antenna  40  from the influence of drive  38  (e.g., to prevent rotating disk  32  from influencing the radio-frequency antenna signals that are associated with antenna  40  due to the Doppler effect). 
     Due to the relatively close proximity of antenna  40  to slot  22 , radio-frequency signals can be received and transmitted through slot  22 . This is illustrated by radio-frequency signal paths  42 . During signal transmissions, radio-frequency signals may be transmitted from antenna  40  through slot  22 . These transmitted signals may be received by radio-frequency (RF) equipment  46 . Equipment  46  may transmit radio-frequency signals that are received by antenna  40  through slot  22 . Equipment  46  may be, for example, a cellular telephone base station, a peer device, a wireless router, a computer with a wireless adapter, a storage device with wireless communications circuitry, a portable electronic device, a satellite, a radio tower, or any other suitable electronic equipment with wireless capabilities. 
     Antenna  40  may be used to handle any suitable communications bands of interest. For example, antennas such as antenna  40  and wireless communications circuitry in computer  10  may be used to handle cellular telephone communications in one or more frequency bands and data communications in one or more communications bands. Typical data communications bands that may be handled by the wireless communications circuitry in computer  10  include the 2.4 GHz band that is sometimes used for Wi-Fi® (IEEE 802.11) and Bluetooth® communications, the 5 GHz band that is sometimes used for Wi-Fi communications, the 1575 MHz Global Positioning System band, and 2G and 3G cellular telephone bands. These bands may be covered using single-band and multiband antennas. For example, cellular telephone communications can be handled using a multiband cellular telephone antenna. A single band antenna may be provided to handle Bluetooth® communications. Antenna  40  may, as an example, be a multiband antenna that handles local area network data communications at 2.4 GHz and 5 GHz (e.g., for IEEE 802.11 communications), a single band antenna that handles 2.4 GHz IEEE 802.11 communications and/or 2.4 GHz Bluetooth® communications, or a single band or multiband antenna that handles other communications frequencies of interest. These are merely examples. Any suitable antenna structures may be used by antenna  40  to cover any communications bands of interest. 
     Antenna  40  may be implemented using any suitable antenna configuration. For example, antenna  40  may be implemented as a monopole antenna, a dipole antenna, a patch antenna, an inverted-F antenna, an L-shaped antenna, a planar inverted-F antenna (PIFA), a slot antenna, a helical antenna, a hybrid antenna including two or more of these antenna structures, or any other suitable antenna structures. 
     With one suitable arrangement, which is described herein as an example, antenna  40  may be implemented using two conductive antenna elements mounted on a substrate. The elements may form a dipole antenna that is fed using an asymmetric transmission line such as a coaxial cable. One of the antenna elements may only weakly radiate and may serve as an impedance matching component, whereas the other of the antenna elements may serve as the primary radiating element. This configuration can improve the efficiency of the antenna at transmitting and receiving radio-frequency signals through slot  22 . 
     The conductive antenna elements that form the dipole may be formed from wires, traces on flex circuit substrates, stamped metal foil patterns, metal parts, or any other suitable conductive structures. If desired, the conductive antenna elements in antenna  40  may be formed from planar traces (patches) on a rigid printed circuit board. This type of configuration is shown in  FIG. 3 . 
     As shown in the example of  FIG. 3 , antenna  40  may have conductive antenna elements such as first conductive antenna element  56  and second conductive antenna element  58 . First conductive antenna element  56  and second conductive antenna element  58  may be formed from a conductive material such as metal. For example, first conductive antenna element  56  and second conductive antenna element  58  may be formed from copper, gold, brass, etc. First and second antenna elements  56  and  58  may be oriented so that their longitudinal axis  78  runs parallel to the longitudinal axis and long edges of slot  22 . 
     First conductive antenna element  56  and second conductive antenna element  58  may be formed as patterned traces on a substrate such as substrate  76 . Substrate  76  may be a dielectric substrate such as a printed circuit board substrate. An illustrative material that may be used as a printed circuit board substrate is fiberglass-filled epoxy. 
     If desired, other suitable dielectric materials may be used for dielectric substrate  76 . For example, conductive elements  56  and  58  may be formed by plating and etching or otherwise depositing patterned copper traces or other conductive traces on a plastic carrier. The use of printed circuit board materials for substrate  76  is merely illustrative. 
     As shown in  FIG. 3 , antenna  40  may be coupled to circuitry in computer  10  using a transmission line such as coaxial cable  48 . If desired, the transmission line may be implemented using a microstrip transmission line structure or other suitable transmission line configuration. The use of coaxial cable to transmit and receive radio-frequency signals for antenna  40  in the  FIG. 3  example is merely illustrative. 
     The lower planar surface of substrate  76  and coaxial cable  48  may be grounded, as indicated by ground terminals  50 . Ground terminals  50  for grounding cable  48  may be located at predetermined positions along the length of cable  48  (e.g., at quarter wavelength spacings) to improve impedance matching and antenna performance. 
     Transmission line structures such as coaxial cables are unbalanced. If desired, a balun may be used to help efficiently feed a balanced antenna structure such as a balanced dipole structure formed by equally sized first and second antenna elements  56  and  58  using an unbalanced transmission line path such as coaxial cable  48 . To conserve space within housing  12 , however, it may be desirable for the balun to be omitted. 
     Without a balun in place, the unbalanced coaxial cable can be used to feed antenna  40  in an unbalanced feed configuration. The first and second antenna elements  56  and  58  may be placed parallel to and close to the edge of slot  22  and other portions of conductive housing  12 . In this position, first and second antenna elements  56  and  58  may interact with the conductive housing and other nearby ground structures to form a transmission line structure in which element  56  serves primarily as an impedance matching element for the unbalanced feed and in which element  58  serves primarily as a radiating element for antenna  40 . 
     As shown in  FIG. 3 , coaxial cable  48  may have a conductive outer braid (shield)  64  that surrounds a dielectric layer  77 . Conductive center conductor  74  may lie in the center of dielectric layer  77 . In regions such as region  78 , conductive outer braid layer  64  may be covered with an insulator such as a plastic jacket. Conductive center conductor  74  may serve as a positive antenna transmission line path and conductive outer braid conductor  64  may serve as a ground antenna transmission line path. Center conductor  74  (the positive antenna transmission line path) may pass through substrate  76  and may contact antenna element  58  at first antenna feed terminal  54 . Outer conductor  64  may pass through substrate  76  and may contact antenna element  56  at second antenna feed terminal  70 . 
     First antenna element  56  and second antenna element  58  may have lengths L. The length L may be selected to enhance radiation efficiency for antenna  40  in a communications band of interest. For example, the length L may be selected to be substantially equal to a quarter of a wavelength at a frequency of interest. 
     With the feed arrangement shown in  FIG. 3 , the first half of dipole antenna  40  (i.e., the portion corresponding to first antenna element  56 ) is approximately at ground potential due to the relatively short distance between points  68  and  70  and does not radiate significantly. Because element  56  is approximately a quarter wavelength in length, there is approximately a quarter wavelength between feed terminal  70  at end  62  of element  56  and open circuit end  60  of element  56 . Open end  60  reflects impedance back to terminal  70  as a short circuit. This transforms the other portion of the dipole antenna (corresponding to second antenna element  58  and its associated ground structures) into an inverted-F antenna structure, as shown schematically in  FIG. 4 . The portion of antenna  40  formed from second element  58  actively radiates. The radiated field can propagate through slot  22  and exit housing  12 . As shown in  FIG. 4 , antenna element  58  and the conductive portions of lower housing  28  that are associated with slot  22  serve as a transmission line. Because these housing portions  22  are maintained at ground potential, the radiated electric field E from antenna  40  tends to be vertical in the orientation of  FIG. 4 . The electric field polarization for antenna  40  is therefore perpendicular to longitudinal axis  78  of elements  58  and  56  and the longitudinal axis of slot  22 . This allows the radio-frequency signals from antenna  40  to propagate through a relatively narrow slot  22  (i.e., through a slot with a small H value in  FIG. 2 ). A conventional monopole having its longitudinal axis aligned with the slot&#39;s longer dimension would have its electric field oriented along the slot&#39;s longer dimension, thereby preventing propagation through a narrow slot. 
     With a dipole antenna structure such as that used by antenna  40  of  FIG. 3 , one half of the dipole radiates and the other half of the dipole serves as an impedance matching element. An advantage of using this type of structure is that the non-radiating half of the dipole exhibits a short-circuit behavior at end  62  of element  56 , but does not have a clear-cut short circuit location as would be the case if an actual short circuit were created at end  62 . This lack of a precisely defined location for the short circuit behavior of element  56  helps to enhance the bandwidth of antenna  40  by more efficiently supporting a greater range of operating frequencies than would otherwise be possible. 
     When no balun is used in feeding element  56  and  58 , there is a modal mismatch between unbalanced transmission line  48  (i.e., the coaxial cable) and the balanced dipole structures of antenna  40 . This modal mismatch creates a current flow on the surface of coaxial cable  48  that competes with antenna  40 . By shorting outer conductor  64  of cable  48  to ground at predetermined locations (grounds  50 ), undesirable radiation cancellation effects arising from the coaxial cable surface current flow may be reduced. Grounding of cable  48  at the predetermined locations may also help to improve repeatability in manufacturing. Grounds  50  may be located at quarter-wavelength spaces along the length of cable  48  or a continuous ground structure may be used. Grounding may be performed by shorting cable  48  to the metal of housing  12  at desired locations. 
     If desired, additional antenna elements may be added to antenna  40  that help direct radiation towards slot  22 . The additional antenna elements may be passive or may be actively fed. The additional antenna elements may serve as reflectors or directors and may help to ensure that field strengths are concentrated towards slot  22 , rather than being directed towards undesired interior portions of housing  12 . 
     A top view of an illustrative configuration that may be used to mount antenna  40  within the interior of housing  12  in the vicinity of slot  22  is shown in  FIG. 5 . As shown in  FIG. 5 , antenna substrate  76  and associated first and second antenna elements  56  and  58  may be mounted to a conductive ground plate such as ground plate  80 . Ground plate  80  may be grounded to an interior planar surface  44  of lower housing portion  28  of housing  12  (i.e., the interior volume of the optical drive portion of computer  10 ). Ground plate  80  may be physically and electrically attached to an inner planar surface of the housing of computer  10  using conductive adhesive and/or fasteners such as screws. 
     Housing  28  may be formed from a conductive material such as aluminum. The aluminum of housing  28  may be provided with an aluminum oxide coating or other insulating surface layer. To allow electrical contact between conductive ground plate  80  and the aluminum (or other metal) of housing portion  28 , the aluminum oxide coating may be removed from region  90  (e.g., by laser removal techniques or chemical removal techniques). This type of arrangement may be used wherever electrical contact to housing  12  is desired. 
     Cable  48  may be grounded to housing portion  28  using grounding structures such as bracket  82 . A screw hole and associated screw  84  may be used to attach bracket  82  and cable  48  to the housing. The screw may, for example, be screwed into a threaded boss in the metal structures of housing  12 . 
     A coaxial cable connector such as a UFL connector  86  may be used to connect coaxial cable  48  to a printed circuit board or other suitable structure. In the example of  FIG. 5 , connector  86  has been attached to a printed circuit board  88  that includes radio-frequency transceiver circuitry. Circuitry such as circuitry  88  may be used in transmitting and receiving radio-frequency signals through antenna  40 . Circuitry  88  may be, for example, a Bluetooth® module that handles Bluetooth® signals at 2.4 GHz. 
     A perspective view of an illustrative antenna  40  of the type shown in  FIG. 5  is shown in  FIG. 6 . As shown in  FIG. 6 , antenna substrate  76  may be attached to a mounting structure such as mounting structure  94  or other suitable support structure. Substrate  76  may be attached to mounting structure  94  using fasteners, adhesive, or other suitable attachment mechanisms. In the example of  FIG. 6 , mounting structure  94  has portions that form heat stakes  96  to hold substrate  76  in place on mounting structure  94 . Coaxial cable  48  has plastic coating in region  78 . Elsewhere, coaxial cable  48  may be stripped to expose outer conductor  64 . Conductor  64  may be electrically grounded to ground plate  80  continuously along its length or at discrete locations. In the arrangement shown in  FIG. 6 , outer conductor  64  is periodically connected to ground plate  80  using solder connections  92 . Ground plate  80  may be formed from a sheet of brass or other metal or conductive material. Clip  82  may be formed from metal and may provide additional grounding of outer conductor  62  to housing  12 . 
     Mounting structure  94  may be formed from a dielectric such as plastic. Mounting structure  94  may be connected to grounding plate  80  using a layer of conductive adhesive such as conductive adhesive layer  100 . Antenna substrate support structure  94  may have screw holes such as holes  98  through which screws  102  may pass to screw structure  94  to housing  12 . Lower housing portion  28  may have threaded holes that receive the threads of screws  102 . 
     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: 20081217
Publication Date: 20120918
Grant Date: 20120918
Priority Date: 20081217
Inventors: CAMACHO EDUARDO LOPEZ
CHIANG BING
KOUGH DOUGLAS B.
XU HAO
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F1/1698", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1698", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2266", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q9/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2266", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 42240255