PATENT DOCUMENT

Publication Number: US-8665160-B2
Application Number: US-201113018184-A
Country: US
Kind Code: B2

Title: Antenna, shielding and grounding

Abstract:
A portable computing device is disclosed. The portable computing device can take many forms such as a laptop computer, a tablet computer, and so on. The portable computing device can include a single piece housing formed from a radio opaque material with a cover formed from a radio transparent material. To implement a wireless interface, an antenna stack-up can be provided that allows an antenna to be mounted to a bottom of the cover. Methods and apparatus are provided for improving wireless performance. For instance, in one embodiment, a metal housing can be thinned to improve antenna performance. As another example, a faraday cage can be formed around speaker drivers to improve antenna performance.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a housing having a bottom coupled to four adjoining sidewalls, the sidewalls extending above the bottom to form an interior cavity wherein the housing includes a surface for receiving a cover glass; and 
 an antenna system disposed within the interior cavity, the antenna system comprising
 an antenna for transmitting or receiving wireless signals, 
 an adhesive layer for bonding the antenna to a bottom of the cover glass, and 
 a compressible foam layer wherein the compressible foam layer is configured to exert an upward force on the antenna to provide a relatively constant spacing between the antenna and the bottom of the cover glass and to minimize air gaps between the bottom of the cover glass and the antenna. 
 
 
     
     
       2. The electronic device of  claim 1 , further comprising: an antenna carrier wherein the antenna carrier is disposed between the antenna and the compressible foam layer. 
     
     
       3. The electronic device of  claim 1  further comprising: an adhesive layer for bonding the antenna to the compressible foam layer. 
     
     
       4. The electronic device of  claim 1  wherein the antenna is mounted proximate to an edge of one of the sidewalls and wherein one of the sidewalls is thinned proximate to the antenna to improve antenna performance. 
     
     
       5. The electronic device of  claim 1  wherein the antenna is mounted to a speaker assembly including one or more speaker drivers. 
     
     
       6. The electronic device of  claim 1  wherein the cover glass is formed from a radio transparent material and the housing is formed from a radio opaque material. 
     
     
       7. The electronic device of  claim 1  further comprising: a proximity sensor wherein a power level associated with the antenna is adjusted based on detection of at least one object near the antenna by the proximity sensor. 
     
     
       8. The electronic device of  claim 1  wherein the housing is an aluminum housing. 
     
     
       9. The electronic device of  claim 1  wherein the housing is formed of a single piece. 
     
     
       10. An antenna system for an electronic device including a housing and a transparent cover glass comprising:
 an antenna for transmitting or receiving wireless signals; 
 an adhesive layer bonding the antenna to a bottom of the transparent cover glass; and 
 a compressible foam layer wherein the compressible foam layer is configured to exert an upward force to the antenna to provide a relatively constant spacing between the antenna and the bottom of the transparent cover glass and to minimize air gaps between the bottom of the cover glass and the antenna. 
 
     
     
       11. The antenna system of  claim 10  wherein the compressible foam layer is compressed when the transparent cover glass is secured to the housing. 
     
     
       12. The antenna system of  claim 11 , wherein the housing is formed from a metal. 
     
     
       13. The antenna system of  claim 12 , wherein the antenna is grounded to the metal. 
     
     
       14. The antenna system of  claim 10 , further comprising an antenna carrier disposed between the antenna and the compressible foam layer. 
     
     
       15. The antenna system of  claim 14 , wherein the housing includes an RF antenna window for receiving the antenna carrier. 
     
     
       16. The antenna system of  claim 10 , further comprising: a proximity sensor for determining whether an object is proximate to the antenna. 
     
     
       17. The antenna system of  claim 16 , wherein a power level of the antenna is adjusted when the object is determined to be proximate to the antenna. 
     
     
       18. The antenna system of  claim 16 , further comprising a shield disposed between the proximity sensor and the antenna. 
     
     
       19. The antenna system of  claim 18 , wherein the shield prevents electromagnetic interference generated by the proximity sensor from reaching the antenna. 
     
     
       20. The antenna system of  claim 19 , wherein the housing is formed of a single piece.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This patent application is related to and incorporates by reference in their entireties the following patent applications and issued patents:
     (i) U.S. Pat. No. 8,460,018, entitled “Flat Object Ejector Assembly” by Jules Henry et al.;   (ii) U.S. patent application Ser. No. 13/018,174, entitled “Handheld Portable Device” by Stephen R. McClure et al.;   (iii) U.S. Pat. No. 8,570,736, entitled “Components Assembly” by Stephen R. McClure et al.;   (iv) U.S. patent application Ser. No. 13/018,242, entitled “Machining Process and Tools” by Stephen R. McClure et al.   

     BACKGROUND 
     1. Field of the Described Embodiments 
     The described embodiments relate generally to portable computing devices such as laptop computers, tablet computers, and the like. More particularly, antenna systems for portable computing devices and methods of assembling portable computing devices including the antenna systems are described. 
     2. Description of the Related Art 
     From a visual stand point, users often find compact and sleek designs of consumer electronic devices more aesthetically appealing. As an example, portable electronic device designs that are both thin and light-weight are often popular with consumers. To enable this type of design, the portable electronic device can include a thin profile enclosure and a number of different components disposed inside. For instance, a display, a main logic board including a processor and memory, batteries, audio circuitry, speakers and external interface circuitry can be disposed within the thin-profile enclosure. 
     One advantage of a portable electronic device is that it can be transported to and utilized in a number of different environments. While being moved from environment to environment, external communications and data connectivity are desired. To meet this need, a common approach is to implement a wireless solution on the portable electronic device. The wireless solution can include implementing a wireless protocol and providing one or more antennas on the device. 
     A design objective for a wireless solution is consistent wireless performance under a wide range of operating conditions. One challenge to obtaining consistent wireless performance is that materials that are desirable for meeting an aspect of the over-all design different from the wireless performance can negatively affect its wireless performance. For instance, to meet strength and stiffness objectives, it may be desirable to use materials for the enclosure or the device components that are radio opaque and hence block antenna reception. Another challenge to obtaining consistent wireless performance is that, in a compact device with limited packaging space, components that can generate or that can be induced to generate signals that are detrimental to wireless performance can be packaged in close proximity to the antennas. 
     In view of the foregoing, there is a need for methods and apparatus for improving wireless performance in portable electronic devices. 
     SUMMARY OF THE DESCRIBED EMBODIMENTS 
     A portable computing device is disclosed. The portable computing device can take many forms such as a laptop computer, a tablet computer, and so on. A single piece housing including an integral bottom and side walls that cooperate to form an interior cavity can be used as an enclosure. Device components, such as a display, battery packs, a main logic board, memory, audio devices can be packaged within the interior cavity. The components can be sealed within the interior cavity using a cover. In one embodiment, the single piece housing can be formed from a radio opaque material and the cover can be formed from a radio transparent material that is also light transparent, such as a transparent glass. 
     An antenna system can be disposed within the interior cavity of the housing underneath the cover. The antenna system can include comprising an antenna for transmitting or receiving wireless signals. An adhesive layer for bonding the antenna to a bottom of the cover glass and a compressible foam layer can be provided. The compressible foam layer can be configured to exert an upward force on the antenna to provide a relatively constant spacing between the antenna and the bottom of the cover and to minimize air gaps between the bottom of the cover and the antenna. The relative constant spacing and the minimal air gaps may help to improve the performance of a wireless solution implemented using the antenna. 
     In one embodiment, the antenna can be bonded to the compressible foam layer. In another embodiment, an antenna carrier can be disposed between the antenna and the compressible foam layer where antenna and the compressible foam can each be bonded to the antenna carrier. An RF antenna window can be provided with the housing. In one embodiment, the antenna carrier can be configured to fit within the RF antenna window. 
     In another embodiment, a proximity sensor can be coupled to the antenna carrier, such as by bonding the proximity sensor the compressible foam layer. The proximity sensor can be used to detect objects near the antenna. When an object is detected near the antenna, a power level associated with the antenna can be adjusted. A shield can be disposed between the proximity sensor and the antenna. The shield can be used to prevent electromagnetic interference generated by the proximity sensor from reaching the antenna. 
     Another aspect of the invention provides a system. The system can include a metal housing having a surface for receiving a cover glass, a speaker assembly and an antenna system. The speaker assembly can have a) a speaker housing having a metal portion for enclosing at least one speaker driver; b) a connector for grounding the speaker drivers to the metal portion of the speaker housing; c) a conductive material wrapped around the speaker housing for forming a faraday cage around the at least one speaker driver, the conductive material grounded to the metal portion and the metal housing. The antenna system can be mounted to a bottom of the cover glass and to the speaker assembly. Further, the antenna system can be grounded to the metal housing. In one embodiment, the antenna system can be located near one side edge of the metal housing. The thickness of the metal housing on the side edge proximate to the antenna system can be thinned to a performance of the antenna system. 
     Another aspect relates to a method of assembling an electronic device having a housing and a cover glass. The method can bonding an adhesive layer to an antenna, coupling a compressible layer of foam to the antenna; and bonding the antenna to the bottom of the cover glass where the compressible foam layer is configured to exert an upward force to the antenna to provide a relatively constant spacing between the antenna and the bottom of the cover glass and to minimize air gaps between the bottom of the cover glass and the antenna. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1A  shows a top view of a portable computing device in accordance with the described embodiments. 
         FIG. 1B  shows a perspective top view of a portable computing device in accordance with the described embodiments. 
         FIG. 2  shows a perspective view of an exterior portion of a housing in accordance with the described embodiments. 
         FIG. 3A  shows a simplified top view of the interior of the housing in accordance with the described embodiments. 
         FIG. 3B  shows a perspective view of an interior portion of a housing in accordance with the described embodiments. 
         FIG. 3C  shows a perspective view of an antenna window mounted to a housing in accordance with the described embodiments. 
         FIGS. 4A-4C  show side views of antenna stack-ups in accordance with the preferred embodiments. 
         FIG. 5  shows a side view of a stack-up for bonding a cover to the housing. 
         FIGS. 6A and 6B  show perspective views an antenna stack-up located near an outer edge of a housing in accordance with the described embodiments. 
         FIG. 7  is a perspective view of a speaker assembly in accordance with the described embodiments. 
         FIG. 8  shows a side view of a display stack-up in accordance with the described embodiments. 
         FIGS. 9A and 9B  show methods of generating an antenna stack-up for a portable device in accordance with the described embodiments. 
         FIG. 10  is a block diagram of an arrangement of functional modules utilized by a portable electronic device in accordance with the described embodiments. 
         FIG. 11  is a block diagram of an electronic device suitable for use with the described embodiments. 
     
    
    
     DESCRIBED EMBODIMENTS 
     In the following paper, numerous specific details are set forth to provide a thorough understanding of the concepts underlying the described embodiments. It will be apparent, however, to one skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the underlying concepts. 
     This paper discusses an aesthetically pleasing portable computing device that is easy to carry with one hand and operate with the other. A wireless solution can be implemented on the portable computing device. The wireless solution can involve implementing a wireless protocol and providing one or more antennas for receiving and transmitting wireless signals. The wireless solution can enable wireless communications with different wireless networks that the portable device encounters as it moved from location to location. In particular embodiments, antenna stack-ups, stack-up placement, housing and component designs are described that can be used to improve the wireless performance of the portable computing device. 
     The portable computing device can utilize a single piece housing and an aesthetically pleasing protective top layer that can be formed of any of a number of durable and strong yet transparent materials such as highly polished glass or plastic. For the remainder of this discussion, however, the protective top layer can take the form of highly polished cover glass without any loss in generality. The single piece housing can be used to enclose and protect various device components, such as a display assembly, main logic board, touch screen interface, batteries, memory, external interfaces, such as antennas used for wireless communications, and switches. 
     The single piece housing can be formed from plastic or metal. In the case where the single piece housing is formed of metal, a metal such as aluminum can be used. In one embodiment, the metal can be initially provided as a single billet that is subsequently machined. The single billet of material can be formed into a shape appropriate for housing various internal components as well as providing various openings into which switches, connectors, displays, and so on can be accommodated. In general, the single piece housing can be forged, molded, or otherwise processed into a desired shape. 
     One disadvantage of selecting a metal to use a housing material is that metals are generally opaque to radio signals. Thus, a selection of a metal material for the housing can affect antenna placement, i.e., the antennas need to be placed in a location of the housing where radio signals are not blocked by surrounding materials that are radio opaque. One of the advantages to using metal for the housing is ability of metal to provide good electrical grounding for any internal components requiring a good ground plane. For example, performance of a built in RF antenna can be substantially improved when a good ground plane is provided. Moreover, a good ground plane can be used to help mitigate the deleterious effects caused by, for example, of electromagnetic interference (EMI) and/or electrostatic discharge (ESD). However, if an RF antenna is present within the housing, a portion of the housing (if metal) may be given over to a radio transparent portion. 
     These and other embodiments are discussed below with reference to  FIGS. 1A-11 . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. 
     Achieving a wireless solution that provides consistent wireless performance over a wide-range of operating conditions can involve considering the relative radio transparency or opacity of each the components of the portable device, the layout of the components relative to one another and an ability of each component to generate signals that can interfere with wireless reception. Thus, first, prior to describing particular features of the wireless solution, features of the portable computing device including features affecting the wireless solution are described in general with respect to  FIGS. 1A-3C . Then, a more detailed discussion of apparatus and method associated with implementing the wireless solution are described with respect to  FIGS. 4A-9B . Finally, the operation of a portable computing device that can incorporate one or more embodiments of the apparatus and the methods, described herein is described, with respect to  FIGS. 10 and 11 . 
       FIG. 1A  illustrates a specific embodiment of portable computing device  100 . More specifically,  FIG. 1A  shows a full top view of fully assembled portable computing device  100 . Portable computing device  100  can process data and more particularly media data such as audio, video, images, etc. By way of example, portable computing device  100  can generally correspond to a device that can perform as a music player, game player, video player, personal digital assistant (PDA), tablet computer and/or the like. With regards to being handheld, portable computing device  100  can be held in one hand by a user while being operated by the user&#39;s other hand (i.e., no reference surface such as a desktop is needed). For example, the user can hold portable computing device  100  in one hand and operate portable computing device  100  with the other hand by, for example, operating a volume switch, a hold switch, or by providing inputs to a touch sensitive surface such as a display or pad. The device can also be operated while it is resting on a surface, such as a table. 
     Portable computing device  100  can include a single piece housing  102  that can be formed from any number of materials such as plastic or metal which can be forged, molded, machined or otherwise processed into a desired shape. In those cases where portable computing device  100  has a metal housing and incorporates RF based functionality, it may be advantageous to provide at least a portion of housing  102  in the form of radio (or RF) transparent materials such as ceramic, or plastic. An example of a housing including radio transparent portion is described in more detail with respect to  FIGS. 3B and 3C . In other embodiments, it may be advantageous to place an antenna in a location where the amount of metal has been minimized. Details of such an antenna placement are described with respect to  FIGS. 6A and 6B . 
     Returning to  FIG. 1A , housing  102  can be configured to at least partially enclose any suitable number of internal components associated with the portable computing device  100 . For example, housing  102  can enclose and support internally various structural and electrical components (including integrated circuit chips and other circuitry) to provide computing operations for portable computing device. The integrated circuits can take the form of chips, chip sets, modules any of which can be surface mounted to a printed circuit board, or PCB, or other support structure. For example, a main logic board (MLB) can have integrated circuits mounted thereon that can include at least a microprocessor, semi-conductor (such as FLASH) memory, various support circuits and so on. 
     Housing  102  can include opening  104  for placing internal components and may be sized to accommodate a display assembly or system suitable for providing a user with at least visual content as for example via a display. In some cases, the display system can include touch sensitive capabilities providing the user with the ability to provide tactile inputs to portable computing device  100  using touch inputs. The touch sensitive capabilities can generate signals that can interfere with wireless performance unless the touch sensor is well-grounded. A display-stack up including touch capabilities and a grounding scheme for the touch sensor is described with respect to  FIG. 8 . 
     The display system can be formed and installed separately from a cover  106 . In particular embodiments, the cover  106  can take the form of cover glass substantially filling opening  104 . Trim bead  108  can be used to form a gasket between cover glass  106  and housing  102 . Trim bead  108  can be formed of a resilient material such as a plastic along the lines of thermoplastic urethane or TPU. In this way, trim bead  108  can provide protection against environmental contaminants from entering the interior of portable computing device  100 .  FIGS. 5 and 6A  some of the possible configurations of the trim bead  108  relative to the cover  106  and the housing  102 . 
     The cover  106  can be formed of polycarbonate or other appropriate plastic or highly polished glass. Typically, these materials can be made to be radio transparent. Thus, in some embodiments, it can be advantageous to locate antennas close to the cover  106 . Various antenna stack-ups that can be used for mounting an antenna close to the cover glass  106  are described in more detail with respect to  FIGS. 4A-4C . 
     Although not shown, the display panel underlying cover glass  106  can be used to display images using any suitable display technology, such as LCD, LED, OLED, electronic or e-inks, and so on. The display can present visual content that can include video, still images, as well as icons such as graphical user interface (GUI) that can provide information the user (e.g., text, objects, graphics) as well as receive user provided inputs. In some cases, displayed icons can be moved by a user to a more convenient location on the display. For example, GUI can be moved by the user manually dragging GUI from one location to a more convenient location. The display can also provide a user with tactile feedback provided by a number of haptic actuators usually, but not always, arranged in an array of haptic actuators incorporated into the display. In this way, the haptic actuators can provide the user with tactile feedback. 
     In one embodiment, the display assembly and cover glass can be provided as an integrated unit for installation into the housing. In another embodiment, the display assembly and the cover glass  106  can be installed separately. Display assembly may be placed and secured within the cavity using a variety of mechanisms. In one embodiment, the display assembly and the housing  102  can include alignment points for receiving a fixture. The fixture can be used to accurately align the display assembly with the housing. Then, after the display assembly is aligned with the housing, it can be secured to the housing  102  using fasteners. 
     Portable computing device  100  can include a number of mechanical controls for controlling or otherwise modifying certain functions of portable computing device  100 . For example, power switch  114  can be used to manually power on or power off portable computing device  100 . A slider switch  116  can be provided for controlling one or more different functions of the portable computing device. In one embodiment, the slider switch  116  can be used to provide a muting feature where the button  116  can be used to mute any audio output provided by portable computing device  100 . The volume switch  118  can be used to increase/decrease volume of the audio output by portable computing device  100 . It should be noted that each of the above described input mechanisms are typically disposed through an opening in housing  102  such that they can couple to internal components. In some embodiments, portable computing device  100  can include an image capture module  98  configured to provide still or video images. The placement may be widely varied and may include one or more locations including for example front and back of the device, i.e., one for capturing images through the back housing, the other for capturing images through the cover glass. 
     As described above, the portable computing device  100  can include a mechanism for wireless communications. As either a transceiver type device or receiver only, such as a radio, portable computing device  100  can include an antenna that can be disposed internal to a radio transparent portion of housing  102 . In other embodiments, a portion of housing  102  can be replaced with radio transparent material in the form of an antenna window described in more detail below. In some embodiments, an antenna can be attached to an underside of the cover glass  106 . The radio transparent material can include, for example, plastic, ceramic, and so on. The wireless communications can be based on many different wireless protocols including for example 3G, 2G, Bluetooth, RF, 802.11, FM, AM, and so on. Any number of antennas may be used, which can use a single window or multiple windows depending on the needs of the system. In particular embodiments, one or more the antennas can be configured to receive GPS signals. The GPS signals can be processed by the portable computing device  100  to determine a proximate location of the device. 
     The portable computing device can be used on a wireless data network, such as a cellular data network. Access to the cellular data network can require the use of a Subscriber Identity Module (SIM) or SIM card. In one embodiment, the device  100  can include an opening  110   b  that allows a SIM card to inserted or removed. In a particular embodiment, the SIM card can be carried on a SIM card tray that can extend from a side of the housing  102 . The housing can include an opening  110   a  that allows an ejector for the SIM card tray to be actuated such that the SIM card tray is extended from the housing. The openings,  110   a  and  110   b , for the SIM card tray are shown in  FIG. 3B . 
       FIG. 1B  shows a perspective top view of portable computing device  100  in accordance with the described embodiments. As shown in  FIG. 1B , portable computing device  100  can include one or more speakers used to output audible sound. The sounds generated by the one or more internal speakers can pass through the housing  102  via speaker grill  120 . In one embodiment, the speaker grill  120  can be formed as a number of small openings machined into the housing  102 . 
     In a particular embodiment, an antenna stack-up can be mounted to the top of a speaker assembly that is mounted in the housing  102  proximate to the speaker grill  120 . A faraday cage can be formed around the speaker assembly to shield the antenna from EMI generated by the speaker. In one embodiment, the faraday cage can be formed by wrapping conductive tape on and around the speaker(s) in the speaker assembly. The conductive tape can serve multiple purposes. The conductive tape can be used to 1) shield the antenna(s) from EMI, 2) provide a constant ground plane between the antenna(s) and any variation in the position, size and shape of the metal components and 3) fill gaps and openings between the metal objects that could resonate at radio frequencies and reduce antenna performance. Details of this embodiment are described below with  FIGS. 4C and 7 . 
     The portable computing device  100  can also include one or more connectors for transferring data and/or power to and from portable computing device  100 . For example, portable computing device  100  can include multiple data ports, one for each configuration of portrait mode and landscape mode. However, the currently described embodiment includes single data port  122  that can be formed of connector assembly  124  accommodated within an opening formed along a first side of housing  102 . In this way, portable computing device  100  can use data port  122  to communicate with external devices when portable computing device  100  is mounted in docking station. It should be noted that in some cases, portable computing device  100  can include an orientation sensor or an accelerometer that can sense the orientation or movement of portable computing device  100 . The sensor can then provide an appropriate signal which will then cause portable computing device  100  to present visual content in an appropriate orientation. 
     Connector assembly  124  can be any size deemed appropriate such as, for example, a  30  pin connector. In some cases, the connector assembly  124  can serve as both a data and power port thus obviating the need for a separate power connector. Connector assembly  124  can be widely varied. In one embodiment, connector assembly  124  can take the form of a peripheral bus connector. These types of connectors include both power and data functionality, thereby allowing both power delivery and data communications to occur between the portable computing device  100  and the host device when the portable computing device  100  is connected to the host device. In some cases, the host device can provide power to the media portable computing device  100  that can be used to operate the portable computing device  100  and/or charge a battery included therein concurrently with the operating. 
       FIG. 2  shows a perspective view of an exterior portion of a housing  102  prior to assembly. The exterior portion can act as a bottom portion of the device after assembly. An interior portion of the housing and its associated features, which encloses device components such as a display assembly and main logic board, is described with respect to  FIG. 3B . In one embodiment, the housing can be formed via machining of a single billet of material, such as a single billet of aluminum. In  FIG. 2 , a portion of the billet can have been machined to form the general outer shape of the exterior portion of the housing. In other embodiments, the billet can be cast into some shape that is closer to the final shape of the housing prior to beginning machining to produce the final housing shape. 
     The housing  102  includes a substantially flat portion  144  surrounded by curved side walls  146 . In one embodiment, the housing  102  can have a maximum thickness of less than 1 cm. In a particular embodiment, the maximum thickness is about 8 mm. In  FIG. 2 , the geometry is provided for the purposes of illustration only. In different embodiments, the curvature on the side walls, such as  146 , and the area of the flat portion  144  can be varied. In one embodiment, rather than a flat portion joined by curved side walls, the sidewalls and flat portion can be combined into a shape with a continuous profile, such as conforming to a continuous spline curve. In yet other embodiments, rather than using curved side walls, the side walls can be substantially flat and joined to the substantially flat portion via a specified radius of curvature. 
     Openings can be formed in the flat portion  144  and the sidewalls  146 . The openings can be used for various purposes that involve functional as wells as cosmetic considerations. In one example, the openings can be used for switches. As shown in  FIG. 2 , a number of switch openings are formed in the side walls. For instance, opening  136  is for a power control switch, opening  140  is for a slider switch and opening  142  is for a volume switch. The size of the openings can depend on the size of the switch. For example, opening  142  can be for a volume rocker switch which can be larger than a power control switch or the slider switch. 
     In another example, openings can be formed in the housing for external connectors. For example, an opening  134  is provided in the side wall for an audio port, such as for a head phone connector. In yet another example (see  FIG. 1B  and  FIG. 3B ), an opening can be provided for an external data and power connector, such as a 30-pin connector. Closer to the substantially flat portion of the housing  144 , opening  138  can be provided for a rear facing image capture device. 
     The housing  102  can be formed from a radio opaque material, such as a metal. In a particular embodiment, the housing can include a cut-out portion for placement of an RF antenna window. One or more antenna can be placed in the RF antenna window. The housing can include a cut-out for receiving the RF antenna window  132 . The RF antenna window can be formed from a radio transparent material, such as a plastic, to improve wireless data reception for the device. In  FIG. 2 , the RF antenna window is shown an installed position extending across the side wall and ending proximate to the substantially flat portion  144  of the housing. The RF antenna window  132  can be shaped to match the surface curvature profiles of the adjacent sidewalls. A more detailed view of the RF antenna window  132  and surrounding support structure on the housing are described in more detail with respect to  FIGS. 3B and 3C . 
     In particular embodiments, a device can be configured to access a data network via one or more wireless protocols. For example, using a protocol such as Wi-Fi, a device can be configured to access the Internet via a wireless access point. As another example, using a wireless protocol, such as GSM or CDMA, device can be configured to access a cellular data network via a local cell phone tower. A device implementing two wireless protocols, such as Wi-Fi and GSM or Wi-Fi and CDMA, can employ different antenna system, one for the Wi-Fi and one for the GSM or CDMA. In addition, one or more of the antenna systems can also be used to receive GPS signals that can be used to determine a proximate location of the device. 
     Typically, a component, such as the RF antenna window  132 , can be used to implement a cellular data network connection using GSM or CDMA. To implement a wireless protocol, such as Wi-Fi, the RF antenna window  132  may not be necessary. Thus, in some embodiments, a housing can be formed without an opening for the RF antenna window  132 . As an example, the antenna stack-up in  FIG. 4C  can be used without the RF antenna window  132 . 
     In embodiments where an RF antenna window, such as  132 , is not used, the housing  102  can extend over the surface where RF antenna window  132  is located in  FIG. 2  to conform to the surrounding curvature of the sidewall. Thus, the area where the RF antenna window  132  is located can be formed from the same material as the other portions of the housing  102  and machined in a manner similar to the other sidewalls of the housing. 
       FIG. 3A  shows a top view of a simplified housing  102  showing a cavity with a front opening for one embodiment. A more detailed perspective view of a housing is described with respect to  FIG. 3B . In  3 A, the housing  102  can include substantially flat bottom portions  148   a  and  148   b . The flat bottom portions,  148   a  and  148   b , can be at different heights or a single height. In one embodiment, the flat bottom portions,  148  and  148   b , can be substantially parallel with the flat exterior bottom  144  of the housing described above with respect to  FIG. 2 . The flat bottom portions,  148   a  and  148   b , can transition into sidewalls that extend above the bottom of the cavity. 
     The sidewalls can be undercut to form ledges, such as ledges  156   a ,  156   b ,  156   c  and  156   d  that extend into the center of the cavity from the sidewalls. In one embodiment, the ledges can include portions at different heights. The width of the ledges can vary across each side and vary from side to side. For instance, the width of the ledge  156   a  can be thinner than ledge  156   d.    
     Brackets, such as  150   a ,  150   b ,  150   c  and  150   d , can be placed at each corner of the housing. The brackets can be formed from a metal, such as stainless steel. The brackets can be configured to add structural stiffness to the housing. During an impact event, such as an impact to the corner of the housing, the corner brackets can limit the amount of impact damage, such as damage to a cover glass. To prevent degradation in the wireless performance, the brackets can be grounded to the housing  102  using an open cell conductive foam. 
     In one embodiment, components, such as the batteries, can be disposed within regions  148   a  and  148   b . For instance, in one embodiment, a number of battery packs can be bonded using PSA strips to the housing in region  148   a . In one embodiment, three battery packs can be adhered to flat region  148   a  using adhesive that can take the form of adhesive strips such as PSA. Using adhesive strips can slightly elevate the batteries and provide room for the batteries packs to expand during operation. As another example, in region  148   b , a number of PCBs can be placed. The number and type of PCBs can vary from embodiment to embodiment depending on the functionality of the device. A few examples of PCBs that can be secured to the housing in this region include but are not limited to a main logic board, a battery management unit, and/or a RF circuit board. The RF circuit board can also include GPS circuitry. 
       FIG. 3B  shows a perspective view of an interior portion of a housing  102  that can be formed using a CNC based machining process. The exterior portion of the housing  102  can also be formed using a CNC based machining process. Device components, such as a display, processor boards, memory, and audio devices can be secured within a cavity formed by the housing. It should be noted that throughout the following discussion, the term “CNC” is used. The abbreviation CNC stands for computer numerical control and refers specifically to a computer controller that reads computer instructions and drives a machine tool (a powered mechanical device typically used to fabricate components by the selective removal of material). It should be noted however, that any appropriate machining operation can be used to implement the described embodiments and is not strictly limited to those practices associated with CNC. 
     In the embodiment in  FIG. 3B , the housing  102  includes a cut-out for the RF antenna window  132 . The antenna window  132  can include a number cavities, such as  162 ,  160   a  and  160   b . In one embodiment, cavities  160   a  and  160   b  can be configured to receive an antenna carrier that includes an antenna. One embodiment of a stack-up for the antenna carrier is described with respect to  FIGS. 4A and 4B . Cavity  162  can be used to receive a camera assembly. 
     The antenna window can include openings, such as  164   a  and  164   b , that are aligned with openings in the housing  102  that allow wiring to extend from an interior of the housing to the RF antenna window. For instance, the wiring can extend from the antennas to allow a communication connection to be established with the main logic board. The openings in the housing  102  that can allow connections into the antenna window  132  are shown in  FIG. 3C . 
     The housing  102  can include a number of features adjacent to the sidewalls of the housing and arranged around a perimeter of the housing. For instance, speaker holes  120  can be machined into one of the sidewalls. In one embodiment, a speaker assembly can be mounted proximate to the speaker holes  120  where an antenna is mounted on top of the speaker assembly. The speaker can be coupled to the housing via attachment points  158 . As is described in more detail with respect to  FIGS. 6A and 6B , the antenna can be positioned near a strengthening bracket  152  located over the data port  122  where the housing proximate to the antenna on the adjacent sidewall is thinned to improve the wireless performance of the antenna. 
     In this embodiment, the antenna mounted on top of the speaker assembly can be bonded to a bottom of the cover glass. A mechanism such as a compressible foam can be used to press the antenna against the bottom of the cover glass to help to form a good seal between the cover glass and the antenna during the bonding process. Prior to bonding the antenna to the bottom of the cover glass, the antenna and the cover glass can be aligned with one another. The speaker assembly can be mounted on features within the interior of the housing  102  that are well controlled relative to the glass mounting surface so that the foam compliance needed to align the antenna to the glass is minimized. 
       FIG. 3C  shows a perspective view  200  of an antenna window  132  mounted to the housing  102  from a different view than shown with respect to  FIG. 3B . As describe above, the RF antenna window can be configured to support one or more antenna carriers within cavities of the window. As described above, the RF antenna window  132  can optionally include a cavity  162  for supporting an image capture device and/or sensor assembly. 
     The housing  102  can include a recessed portion in which the RF antenna window  132  is disposed. In one embodiment, the antenna window  132  can be supported by the support wall  170  formed in the housing  102 . The RF antenna window  132  can include a lip portion  166  that hangs over the support wall  170 . The lip portion  166  can help to prevent the antenna tray from being pulled out of the housing. The RF antenna window  132  can be bonded to the housing an adhesive, such as an epoxy or a PSA tape. The antenna tray  132  can be bonded along the lip portion and exterior facing surfaces of the support wall  170 . 
     The support wall  170  can include a number of openings, such as openings  168 . The openings  168  can be aligned with openings in the RF antenna window  132 . The openings can allow wires to be passed through the housing and into the antenna carrier to reach components in the RF antenna window  132 , such as one or more antennas and the image capture and/or sensor assembly. In alternate embodiments, an RF antenna window  132  and its associated antennas can be removed. In this embodiment, the support wall  170  can be removed and the exterior and interior portions of the housing proximate to the antenna location can be formed from the same material as the remaining portions of the housing. 
       FIGS. 4A-4C  show side views of antenna stack-ups allowing an antenna to be mounted to the bottom of a cover glass  106 . In  FIG. 4A , an antenna  174  is mounted to a first surface portion of an antenna carrier  136 . The antenna  174  can be mounted to the antenna carrier  136  using an adhesive layer  172   b , such as a PSA tape or an epoxy. In one embodiment, the antenna carrier  136  can be shaped to fit within a particular space available within the housing. For example, in one embodiment, the antenna carrier can be shaped to fit within a cavity, such as  160   a  or  160   b , associated with the RF antenna window  132  (see  FIGS. 3B and 3C ). 
     In a particular embodiment, a piece of compressible foam  178  can be bonded to a second surface portion of the antenna carrier  136  using an adhesive layer, such as  176 . The adhesive layer  176  can be formed from a bonding agent, such as a PSA tape or a liquid epoxy. After the compressible foam  178  is secured to the antenna carrier, the antenna carrier  136  can be placed within a space, such as a space within the RF antenna window  132 . 
     In one embodiment, the adhesive layer  172   a  can be provided with a protective film (not shown) to prevent items from sticking to its top before the cover  106  is secured to the antenna stack-up  202 . The cover glass  106  and the antenna  174  can be aligned with one another and the film can be removed to bond the antenna to the cover glass. 
     When cover  106  is lowered into place, the adhesive layer  172   a  can bond the antenna  174  to a bottom surface of the cover. The over-all stack up can be configured so that a top height of the stack-up  202  is higher than the height  177  at which the bottom of the cover  106  is secured. Thus, when the cover glass  106  is secured into place, a downward force can be exerted on the stack-up by the cover glass. The downward force can result in the foam  178  decreasing in height such that the foam exerts a force against the bottom of the cover  106 . 
     The upward force exerted by the foam  178  can push the adhesive layer  172   a  against the bottom of the cover and can help to minimize air gaps that can form between the adhesive layer  172   a  and the cover  106 . Air gaps can affect antenna performance. Thus, minimizing air gaps between the bottom of the cover  106  and the adhesive layer  172   a  can help to prevent variations in antenna performance from device to device that can result from a presence of an air gap between the antenna and the cover glass. 
     The compressible foams described herein can include pores and cavities often referred to as cells. Depending the structure and formulation of the cells, the cells can be described as “open cell,” “semi-open cell,” and “closed cell.” Foam components can be used at a number of different locations within the housing. In different embodiments, the foam formulation that is used, the shape of the foam component and its thickness can vary from location to location. 
     The force exerted by the foam can increase significantly if the foam is compressed over a certain percentage from its original size, such as to 20% smaller or more from its original size. The compression limit where the force starts increasing significantly can be approached as all of the cells become closed as a result of the compression. The compression limit where forces starts increasing significantly after the foam is compressed beyond a certain limit can vary from foam type to foam type. However, the foam can be sized such that this limit is not reached when the cover is bonded in place over the foam. 
     In alternate embodiments, rather using a compressible foam or in conjunction with a compressible foam, other mechanisms can be used to push the antenna against the bottom of the cover glass or against some other desired surface to help to form a good seal. In general, there are different configurations of mechanisms that can use force generating components, such as “spring-like” elements, to accomplish this objective of pushing the antenna against the cover glass. As an example, in different embodiments, a mechanism can include the use of a cantilevered spring, a coiled geometry or gas-filled pillows. In addition, if multiple antennas are installed in this manner, the mechanism used to push the antenna a desired surface can vary from location to location. 
     For antenna consistency, it can be desirable to have a certain amount of force pushing against the antenna during the bonding process to the cover glass. As described above, a force generating mechanism such as a compressible foam can be used to exert the force. However, after the antenna is bonded to the cover glass and the cover glass is secured to the housing, it can be undesirable to have too much force pushing against the antenna and hence the cover glass because the force pushing on the cover via the antenna can potentially reduce the adhesion of the cover glass to the housing resulting in reliability issues. 
     To prevent too much force being generated after the cover glass is attached to the housing, a nominal force can be selected that accounts for variations in the force that can be generated as a result of assembly tolerances where in the worst case enough force is still provided to the antenna to meet the minimum force requirements needed to generate the desired antenna performance. In the case of foam, assembly tolerances can result in greater or smaller amounts of foam compression and hence greater or smaller amounts of force exerted by the foam on the antenna. To provide the nominal force using foam, a foam thickness can be selected where the amount of compression anticipated to be exerted on the foam is far from the over compression limit and where thickness variations in the foam resulting from assembly tolerances are small relative to the overall foam thickness. 
     In alternate embodiments, a force generating mechanism can be provided that exerts the nominal force on the antenna during bonding of the antenna to the cover glass but where the nominal force provided by the force generating mechanism is decreased or eliminated after the bonding of the antenna to the cover glass, such as when the cover glass is secured to the housing. As an example, mechanical snaps can be used on an antenna carrier. The mechanical snaps can be configured to push the antenna carrier and the antenna against the glass with a particular force profile, but then snap into place after the cover glass reaches its installed position. After snapping into place, the force exerted by the mechanical snaps can be reduced or eliminated. 
     In another example, a friction fit process could be used. An antenna carrier can be configured to interfere with a space in which it is to be installed. For instance, the antenna carrier can include a feature, such as a protuberance, a cavity or rubber gasket, that can cause interference with a surrounding space in which it is to be installed. During installation, the antenna carrier can be placed proximate to the space it is to be installed and then the cover glass can be pushed antenna and the antenna carrier. As the antenna carrier is pushed into its installed position, the friction resulting from the interference provides resistance that pushes antenna carrier and hence the antenna against the cover glass. After the antenna carrier reaches its final position, the force exerted by the antenna carrier can be reduced or eliminated. 
     In yet another example, a semi-rigid, yet deformable material can be placed under antenna carrier, such as a putty or wax. As the antenna carrier is pressed into the deformable material, the nominal force needed to bond the antenna to the glass can be generated. Afterward deformation, the deformable material can set in its deformed shape such that there is no (or little force) pushing against the glass after it is secured into place. 
     In  FIG. 4B , an alternate antenna stack-up  204  is shown. In this embodiment, a proximity sensor  182  is bonded to the foam layer  178 . In addition, a shielding layer  180 , such as a metal shielding layer, is placed between the proximity sensor  182  and the antenna  174 . In one embodiment, the shielding layer can be formed from a metal film. In this embodiment, the shielding layer may not be grounded. The shielding layer  180  can help to prevent the antenna  174  from receiving signals generated by the proximity sensor  182 . In another embodiment, the shielding layer can be grounded to a metal portion of the housing. 
     In one embodiment, the shielding layer  180  can be disposed between the foam  178  and the antenna carrier  136  via adhesive layers  176   a  and  176   b . In other embodiments, the shielding layer  180  can be disposed in another location. For instance, a shielding layer  180  can be built into the antenna carrier  136 . 
     The proximity sensor can be used to detect whether an object, such as a human hand, is close to the RF antenna window  132 . The portable device can be configured to supply variable amounts of power to the antenna  174  and hence, affect a strength of the signal emitted by the antenna  174 . In one embodiment, when an object or surface is detected close to the proximity sensor, the portable device can be configured to reduce an amount of power supplied to the antenna  174 . In another embodiment, if the device includes multiple antennas, a proximity sensor can be provided with each antenna and the amount of power supplied to each antenna can be adjusted on an antenna by antenna basis. Thus, in some embodiments, if an object is detected close to one antenna but not another of the antennas, then power can be reduced to one antenna but not the other antenna. In other embodiments, the power can be reduced to both antennas when an object is detected proximate to one or the other antenna. 
     In  FIG. 4C , another antenna stack-up  206  is shown. In this embodiment, antenna  174  is bonded to the foam  178  via adhesive layer  172   b . The foam  178  is then bonded to an underlying support structure  184  via adhesive layer  182 . The foam  178  can help to generate a good seal with a minimal air gap between the antenna  174  and the cover  106 . As is described in more detail with respect to  FIGS. 6A and 6B , an antenna and foam stack-up, such as  206 , can be bonded to a speaker assembly. 
     With respect to  FIGS. 5 ,  6 A and  6 B, an antenna stack-up configuration is described where the an antenna is secured to the bottom a cover glass close to where the cover glass attaches to the housing. Therefore, with respect to  FIG. 5 , mounting the cover glass to the housing is described in general. When an antenna is mounted close to where the cover glass is attached to the housing, the housing and the apparatus for attaching the cover glass to the housing can be modified. In a particular embodiment, details of these modifications are described with respect to  FIGS. 6A and 6B . 
       FIG. 5  shows a side view of a stack-up  208  for bonding a cover  106  to the housing  102 . The housing  102  can include a surface for receiving a trim bead  108 . The trim bead  108  can be mounted to the housing an adhesive layer, such as  188   a . In one embodiment, the trim bead  108  can be disposed around an outer perimeter of the housing  102 . In the embodiment where an antenna window is used, a portion of the trim bead  108  can extend over the antenna window. The cover  106  can be bonded to the trim bead  108  via an adhesive layer, such as  188   b . When the cover  106  is installed it can enclose underlying structures, such as  190 , which can be associated with various device components. 
       FIG. 6A  shows a perspective views an antenna stack-up located near an outer edge of the housing  102 . In one embodiment, the antenna  194  can be part of an antenna stack-up including a compressible foam material as was described above with respect to  FIG. 4C . In one embodiment, the antenna stack-up can be mounted to a speaker assembly  210 . The antenna can include alignment holes  220  that can be used to align the antenna  194  to the cover glass. The antenna  194  can be coupled to a wire  192  that allows information to be transferred between the antenna and a logic board, such as the main logic board on the device. The information can be related to signals received by the antenna  194  or signals to be broadcast by the antenna. In one embodiment, the antenna  194  can be used to implement a wireless protocol, such as Wi-Fi. 
     To improve wireless performance, it can be desirable to place the antenna close to an edge of the housing. If the housing is formed from a radio opaque material, such as a metal, to improve antenna performance, it can be desirable to thin the housing  102  as much as possible proximate to the antenna while maintaining a relatively uniform thickness of metal next to the antenna. In  FIG. 6A , an antenna  194  is mounted close to one edge of the housing between corner bracket  150   c  and support bracket  152  on the housing  102  (see  FIG. 3B ). In other embodiments, the antenna  194  can be mounted at other locations proximate to the housing. Further, the antenna  194  can be mounted on top a speaker assembly or on top of some other internal structure. Thus, this example is provided for the purposes of illustration only and is not meant to be limiting. 
     In  FIG. 6A , the trim bead  108  includes a cut-out portion. The cut-out portion allows a grounding tab  198  to be grounded to the housing  102  next the antenna  194 . The grounding tab  198  can be secured to the housing  102  via one or more fasteners, such as fasteners  196 . In one embodiment, a cover layer (not shown) can be placed over the fasteners after the grounding tab  198  is secured to the housing. As described above, to improve antenna performance, it can be desirable to thin the housing  102  proximate to the antenna  194 . This feature is illustrated with as follows with respect to  FIG. 6B . 
     In  FIG. 6B , the support bracket  152  is removed to show the underlying structure of the housing. The housing  102  includes a ledge  102   a  for receiving the trim bead  108 . Next, to ledge  102   a , another ledge  102   b  is located. The ledge  102   b  is configured to receive the support bracket  152  shown in  FIG. 6A . The ledge  102   b  is located below ledge  102   a  so that, when the support bracket  152  is resting on the ledge  102   b , the top of the support bracket is about the same height as ledge  102   a . Then, the trim bead  108  can rest across the top surfaces of bracket  150   c , bracket  152  and ledge  102   a.    
     In  FIG. 6B , the distance between side  194   a  and an exterior edge of housing is approximately the distance between locations  102   d  and  102   e  on the housing. The distance is proximately the thickness of the housing at this location. Along side  194   a  of the antenna  194 , the thickness of the housing is relatively constant and is proximately the thickness of the housing between locations  102   d  and  102   e . In  FIG. 6B , it can be seen at location  102   c  on ledge  102   b  that the housing is thicker at this location relative to the thickness of the housing along  194   a , i.e., location  102   d  is closer to the edge of the housing than location  102   c . As described above, providing a relatively thinner housing with a constant thickness proximate to the antenna may help to improve the antenna performance. 
       FIG. 7  is a perspective view of a speaker assembly  210 . As described above, in one embodiment, an antenna stack-up can be mounted on top of the speaker assembly  210 . For example, the antenna can be mounted to the speaker assembly proximately at location  232 . The speaker assembly  210  can include a housing  224  and a connector  234  that allows the speaker to receive signals that are converted into sound. The housing  224  can enclose one or more speaker drivers. In one embodiment, the housing  224  can enclose two speaker drivers. 
     One concern with mounting an antenna, such as  194  in  FIG. 6A , is that magnets in the speaker drivers can generate EMI that can affect the antenna performance. In one embodiment, to mitigate potential EMI from the speaker drivers, each of the drivers can be grounded to a metal portion of the housing  224 . For instance, a first driver can be grounded to metal portion  222  in housing  224  and a second driver can be grounded to a metal portion  226  in housing  224 . Then, a conductive material, such as a conductive tape, can be coupled to each of the metal portions and wrapped around the housing  224 , such that a faraday cage is formed around each speaker driver. For example, conductive tape  234  is coupled to the metal portion  222  and wrapped around the housing  224  and conductive tape  228  is coupled to the metal portion  226  and wrapped around housing  224 . Thus, a faraday cage is formed around each of the two drivers. Finally, the conductive tape used to form the faraday cage, such as  224  and  228 , can be grounded to the housing. 
     In addition, the use of conductive tape can provide other advantages. For instance, the speaker assembly can include metal components that vary in size, shape and their installed position within the assembly. These variations can affect antenna performance depending on where the antenna is installed relative to the metal components. The conductive tape can provide a constant ground plane between the antenna and the metal components that can help mitigate any effects resulting from variations in the size, shape and position of the metal components of the speaker assembly relative to the antenna. Another example potential advantage of using conductive tap is that the conductive tape can be used to fill gaps and openings between metal objects that can resonate at radio frequencies that reduce antenna performance. 
     As noted above, grounding can be important for maintaining consistent antenna performance. In addition, other components can be sensitive to EMI and a good grounding scheme can help to mitigate EMI issues. One component that can be sensitive to EMI is a touch panel, such as a capacitive touch sensor. The touch panel can be located over a display module, such as a display module including an LCD display. A few details in regards to grounding the display module to mitigate EMI issues associated with the proximity of the touch panel to the display module as well as grounding the display module to mitigate EMI issues associated with the proximity of the display module to the one or more antennas is described in more detail as follows. 
     To meet overall thickness objective for the portable computing device, it can be desirable to minimize the thickness of various device components. For example, a display module without a front bezel can used to make the display module thinner. As another example, for a portable device with a touch panel, the touch panel can be placed relatively close to display components associated with the display module, such as an LCD glass associated with an LCD display. In a particular embodiment, a touch panel layer can be located less 1 mm in distance from an EMI generating layer in the display module. The EMI generating layer or layers in a display module can vary depending on the display technology that is utilized and the example of an LCD glass is provided for the purposes of illustration only. 
     As noted above, the EMI generating layer or layers in the display module can be grounded to mitigate EMI effects on the touch panel. In the case of the display module, it is desirable to perform this grounding while not increasing or at least adding a minimum amount of the thickness to the display module. Towards this objective, in one embodiment, a conductive tape can be used to ground the EMI generating display circuitry within the display module to a metal portion of the display module housing, such as grounding thin-film traces on an LCD glass to the metal portion of the housing. In a particular embodiment, the thin-film traces can be ITO traces. 
     The conductive tape can be less than 0.1 mm thick. In a particular embodiment, the conductive tape can be about 0.06 mm thick. The conductive tape can use an adhesive that does not corrode or damage in any manner the substrate to which it is bonded, such as a thin film formed on an LCD glass. The conductive tape can be formed with a color that is cosmetically acceptable. For example, in one embodiment, a visible portion of the conductive tape can be a “black” color. 
     An embodiment of a grounding scheme for a display module is described as follows.  FIG. 8  shows a side view of a stack-up  212  for providing imaging services and touch recognition capabilities. The display module  242  can be disposed beneath the cover glass  106 . A touch panel  246  can be located above the display module  242 . A layer of conductive tape  244  can be provided to ground EMI generating display circuitry in the display module  242 , such as a thin film with circuit traces on an LCD glass, that can affect the touch panel  246 . In one embodiment, a dust shield layer  240  can be disposed above the conductive tape  244  and beneath the cover  106 . 
     In a particular embodiment, one end the conductive tape  244  can be coupled to one or more layers of the EMI generating display circuitry in the display module  242 , such as a film with circuit traces on an LCD glass. Then, the conductive tape  244  can be attached to a metal portion of a housing for the display module  242 . For instance, if the metal portion of the housing extends up the sides of the display module  242 , then the conductive tape can be extended over a top of the display  244  and partially around the side and attached to the metal portion on the side. If the metal portion is on the bottom portion of the display module  242  and does not extend around the sides, then the conductive tape can be extended over a top of the display  244 , around the side and partially onto the bottom portion of the display module. One advantage of using a conductive tape layer, such as  244 , is that it may be thinner than using a corresponding metal structure for grounding purposes. 
     To control interference and antenna resonances between the display circuitry associated with the display module  242  and one or more antennas, the metal chassis of the display module can be grounded to the antenna&#39;s ground plane. In one embodiment, this grounding can be accomplished by cutting slits in the conductive tape associated with the display module  242 , such as  244 , adhering a conductive foam to the display module  242  proximate to the slits and then the compressing the foam into a gap where the foam can contact a conductive surface associated with the antenna&#39;s ground plane. The foam can be compressed in this manner during the installation of the display module  242 . In a particular embodiments, foam can be used at multiple locations to ensure good grounding between the display module and the antenna ground plane. 
       FIG. 9A  shows a method of generating an antenna stack-up for a portable device. In  302 , a shape and a size of the antenna can be determined. The shape and size can be based upon such factors as packaging restrictions and wireless performance considerations. In  304 , the antenna can be bonded to a compressible foam. A bonding agent, such as a pressure sensitive adhesive (PSA), can be used to bond to the antenna to the foam. In  306 , the foam can be bonded to an underlying support structure. In one embodiment, previously described with respect to  FIG. 4C , the foam can be bonded to the support structure associated with a speaker assembly. 
     In  308 , the antenna can be aligned with a cover, such as a cover glass for the portable electronic device. The cover glass can be both transparent to visible light and radio waves. In one embodiment, the antenna assembly can include alignment holes for receiving alignment points on the cover. The cover glass and the antenna can be aligned as part of bonding the cover to the housing. In  310 , the antenna can be bonded to the cover. The antenna can be bonded to the cover using an adhesive, such as a PSA tape. 
     When the antenna is placed against the cover, the foam can be sized such that the foam is compressed. The compression of the foam can exert a force that presses the antenna against the bottom of the cover. The pressure exerted by the foam can help to form a good seal between the cover and the antenna, such as a seal where the air gaps between the antenna and the cover are minimized and relatively constant across the interface between the antenna and the cover, i.e., air bubbles that affect antenna performance are minimized. 
     The force exerted by the foam can increase significantly if the foam is compressed over a certain percentage from its original size, such as to 20% smaller or more from its original size. The limit can be reached when all the open cells of the foam are compressed. The compression limit where forces starts increasing significantly after the foam is compressed beyond a certain limit can vary from foam type to foam type. However, the foam can be sized such that this limit is not reached when the cover is bonded in place over the foam. 
       FIG. 9B  shows another embodiment of a method of generating an antenna stack-up for a portable device. In  312 , the antenna can be sized and shaped. In  314 , the antenna can be bonded to one side of an antenna carrier (e.g., see  136  in  FIGS. 4A and 4B ). The shape of the antenna can be varied. Typically, the shape can be selected to fit within some space specified within the housing where the specified shape can be varied. 
     In  314 , the antenna can be bonded to one surface portion of the antenna carrier. In  316 , a compressible foam, such as an open cell foam, can be bonded to another surface portion of the antenna carrier. In one embodiment (see  FIG. 4B ), a component such as a proximity sensor and a shield material can be bonded to compressible foam. The shield material can shield the antenna from EMI generated by the component. In  316 , the antenna carrier including the antenna can be placed within the housing, such as within a cavity associated with an RF antenna window. In  320 , the antenna can be aligned with a cover glass and then, in  322 , the antenna can be bonded to cover glass. When cover glass is secured into position, the foam can be compressed such that a force is exerted through the antenna carrier that presses the antenna against the cover. Again, the force exerted by the foam can improve the sealing between the antenna and the cover, such as by minimizing the air gaps. Minimizing the air gaps can limit variations in wireless performance from device to device that can result from having air gaps that vary from device to device. Large variations in wireless performance from device to device can be undesirable. 
       FIG. 10  is a block diagram of an arrangement  900  of functional modules utilized by an electronic device. The electronic device can, for example, be tablet device  100 . The arrangement  900  includes an electronic device  902  that is able to output media for a user of the portable media device but also store and retrieve data with respect to data storage  904 . The arrangement  900  also includes a graphical user interface (GUI) manager  906 . The GUI manager  906  operates to control information being provided to and displayed on a display device. The arrangement  900  also includes a communication module  908  that facilitates communication between the portable media device and an accessory device. Still further, the arrangement  900  includes an accessory manager  910  that operates to authenticate and acquire data from an accessory device that can be coupled to the portable media device. 
       FIG. 11  is a block diagram of a electronic device  950  suitable for use with the described embodiments. The electronic device  950  illustrates circuitry of a representative portable media device. The electronic device  950  can include a processor  952  that pertains to a microprocessor or controller for controlling the overall operation of the electronic device  950 . The electronic device  950  can be configured to store media data pertaining to media items in a file system  954  and a cache  956 . The file system  954  can be implemented using a memory device, such as a storage disk, a plurality of disks or solid-state memory, such as flash memory. 
     The file system  954  typically can be configured to provide high capacity storage capability for the electronic device  950 . However, to improve the access time to the file system  954 , the electronic device  950  can also include a cache  956 . As an example, the cache  956  can be a Random-Access Memory (RAM) provided by semiconductor memory. The relative access time to the cache  956 , such as a RAM cache, can be substantially shorter than for other memories, such as flash or disk memory. The cache  956  and the file system  954  may be used in combination because the cache  956  may not have the large storage capacity of the file system  954  as well as non-volatile storage capabilities provided by the memory device hosting the file system  954 . 
     Another advantage of using a cache  956  in combination with the file system  954  is that the file system  954 , when active, consumes more power than does the cache  956 . The use of cache  956  may decrease the active time of the file system  954  and hence reduce the overall power consumed by the electronic device. The power consumption is often a concern when the electronic device  950  is a portable media device that is powered by a battery  974 . 
     The electronic device  950  can also include other types of memory devices. For instance, the electronic device  950  can also include a RAM  970  and a Read-Only Memory (ROM)  972 . In particular embodiments, the ROM  972  can store programs, utilities or processes to be executed in a non-volatile manner. The RAM  970  can be used to provide volatile data storage, such as for the cache  956 . 
     The electronic device  950  can include one or more user input devices, such as input  958  that allow a user of the electronic device  950  to interact with the electronic device  950 . The input devices, such as  958 , can take a variety of forms, such as a button, keypad, dial, touch screen, audio input interface, video/image capture input interface, input in the form of sensor data, etc. Still further, the electronic device  950  includes a display  960  (screen display) that can be controlled by the processor  952  to display information to the user. A data bus  966  can facilitate data transfer between at least the file system  954 , the cache  956 , the processor  952 , and the CODEC  963 . 
     In one embodiment, the electronic device  950  serves to store a plurality of media items (e.g., songs, podcasts, image files and video files, etc.) in the file system  954 . The media items (media assets) can pertain to one or more different types of media content. In one embodiment, the media items are audio tracks (e.g., songs, audio books, and podcasts). In another embodiment, the media items are images (e.g., photos). However, in other embodiments, the media items can be any combination of audio, graphical or video content. 
     When a user desires to have the electronic device play a particular media item, a list of available media items is displayed on the display  960 . Then, using the one or more user input devices, such as  958 , a user can select one of the available media items. The processor  952 , upon receiving a selection of a particular media item, supplies the media data (e.g., audio file) for the particular media item to one or more coder/decoders (CODEC), such as  963 . The CODECs, such as  963 , can be configured to produce output signals for an output device, such as speaker  964  or display  960 . The speaker  964  can be a speaker internal to the media player  950  or external to the electronic device  950 . For example, headphones or earphones that connect to the electronic device  950  would be considered an external speaker. 
     The electronic device  950  can be configured to execute a number of applications besides media playback applications. For instance, the electronic device  950  can be configured execute communication applications, such as voice, text, e-mail or video conferencing applications, gaming applications, web browsing applications as well as many other different types of applications. A user can select one or more applications for execution on the electronic device  950  using the input devices, such as  958 . 
     The electronic device  950  can include an interface  961  that couples to a data link  962 . The data link  962  allows the electronic device  950  to couple to a host computer or to accessory devices. The data link  962  can be provided over a wired connection or a wireless connection. In the case of a wireless connection, the interface  961  can include a wireless transceiver. Sensor  976  can take the form of circuitry for detecting any number of stimuli. For example, sensor  976  can include a Hall Effect sensor responsive to external magnetic field, an audio sensor, a light sensor such as a photometer, a gyroscope, and so on. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Various aspects of the described embodiments can be implemented by software, hardware or a combination of hardware and software. The described embodiments can also be embodied as computer readable code on a computer readable medium for controlling manufacturing operations or as computer readable code on a computer readable medium for controlling a manufacturing line. The computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, DVDs, magnetic tape, optical data storage devices, and carrier waves. The computer readable medium can also be distributed over network-coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the invention. Thus, the foregoing descriptions of specific embodiments of the present invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings. 
     The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents. 
     While the embodiments have been described in terms of several particular embodiments, there are alterations, permutations, and equivalents, which fall within the scope of these general concepts. It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present embodiments. For example, although an extrusion process is preferred method of manufacturing the integral tube, it should be noted that this is not a limitation and that other manufacturing methods can be used (e.g., injection molding). It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the described embodiments.

Metadata:
Filing Date: 20110131
Publication Date: 20140304
Grant Date: 20140304
Priority Date: 20110131
Inventors: UTTERMANN ERIK A.
FRANKLIN JEREMY C.
MCCLURE STEPHEN R.
CORBIN SEAN S.
LI QINGXIANG
GOMEZ ANGULO RODNEY A.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/526", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/2266", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/52", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y10T156/1089", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49016", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01Q1/42", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 46576919