Abstract:
A carrying case for a portable electronic device includes a coupling element that couples to an antenna of the device without establishing a direct electrical connection. The coupling element increases the reception of the device by increasing the effective size of the antenna. The coupling element is designed to correspond to the reception capabilities of the device for which the case is designed. Preferably, the coupling element is a copper foil that is positioned in the case such that it is adjacent the antenna of the device when the device is held within the case. The copper foil is shaped to correspond to a profile of the device. An antenna and signal amplifier can be used in connection with the coupling element to further boost the device&#39;s reception capability.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present application claims priority from co-pending Provisional Patent Application No. 61/018,661 entitled “Reception Boosting Accessory” filed Jan. 2, 2008. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable 
       REFERENCE TO SEQUENCE LISTING OR COMPUTER PROGRAM LISTING APPENDIX 
       [0003]    Not Applicable 
       FIELD OF THE INVENTION 
       [0004]    The present invention is directed toward an accessory for use with an electronic device that electromagnetically couples a signal booster in the case to an antenna of the device to improve the reception of the antenna. 
       BACKGROUND OF THE INVENTION 
       [0005]    A wide variety of electronic devices utilize antennas to receive or send electromagnetic signals. Unfortunately, a better antenna is typically a larger antenna. On small portable devices in particular, a compromise has to be made between reception capability and size and weight restrictions. Often, a small antenna will function perfectly well for most consumers. However, a limited number of individuals located on the fringes of the device&#39;s reception range would strongly prefer better reception. While a device can be retrofitted with a more capable antenna, it is difficult to do so in a suitable, ascetic and economical matter. 
         [0006]    Cases are commonly used to carry a variety of portable electronic devices such as digital music players, cellular telephones, personal computers, data assistants, etc. Unfortunately, these cases may impede the reception of the device&#39;s antenna when the device is positioned within the case. This can further exacerbate the reception problems encountered in some locations. Many cases also suffer from the draw back that the device&#39;s outputs, display and controls are not easily accessible through the case&#39;s exterior. Since each type of device tends to have a different configuration with respect to their inputs and outputs, even devices that are similarly sized may require different case configurations to accommodate their particular set of inputs and outputs. 
         [0007]    In light of the above discussed problems what is needed is an accessory for an electronic device that improves the device&#39;s reception. 
       SUMMARY OF THE INVENTION 
       [0008]    An embodiment of the present invention is directed toward a carrying case for use with a portable electronic device. The carrying case includes a conductive material such as copper foil that functions as a coupling element. The coupling element is positioned in the case such that it is adjacent an antenna of the device when the device is held in the carrying case. The coupling element capacitively or inductively couples to the device antenna and improves the reception of the device. The coupling element is preferably shaped to correspond to a profile of the antenna in the device. A case antenna is electrically connected to the coupling element. The case antenna can be internal or extendable and adjustable. A signal booster may be included in the case to amplify the signal received by the case antenna. The amplified signal is then coupled to the device antenna by the coupling element thereby boosting the device&#39;s reception. A rechargeable battery powers the signal booster. Alternatively, the signal booster can be powered from the device power supply in a parasitic manner. 
         [0009]    Another embodiment of the present invention is directed toward an accessory for an electronic device. The accessory is configured as a replacement panel for a housing of the device. The replacement panel includes a signal boosting element positioned in the panel. The signal boosting element is positioned in the replacement panel such that, when the replacement panel is installed on the device, the signal boosting element is adjacent an antenna of the electronic device. The signal boosting element couples to the device&#39;s antenna thereby improving the reception of the device. 
         [0010]    Yet another embodiment of the present invention is directed toward a case for an electronic device. The case includes a front panel and back panel that connect to substantially enclose the electronic device. A repositionable coupling element is positioned on one of the panels such that it is held adjacent an internal antenna of the device. The coupling element, the exterior of the device and the internal antenna of the device form a capacitor that increases the reception capability of the device. An antenna and amplifier are electrically connected to the coupling element. The coupling element couples the amplified signal received from the amplifier to the antenna of the device when the device is held in the case. A shielding portion prevents unwanted signals from the device from coupling to the coupling element. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0011]      FIG. 1  is an illustration of a device case constructed in accordance with a first embodiment of the present invention; 
           [0012]      FIG. 2  is an illustration of a device case constructed in accordance with an alternative embodiment of the present invention; 
           [0013]      FIG. 3  is an illustration of a device case constructed in accordance with another alternative embodiment of the present invention; 
           [0014]      FIG. 4  is an illustration of an accessory for a device constructed in accordance with an embodiment of the present invention; and 
           [0015]      FIG. 5  is a block diagram of an accessory constructed in accordance with an embodiment of the present invention; 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0016]    Referring now to  FIG. 1 , an illustration of a device case  2  constructed in accordance with an embodiment of the present invention is shown. The case  2  has a capacitively coupling element  4 , constructed from a conductive material such as copper foil, positioned on an inner face  6  of the case. The coupling element  4  is preferably positioned adjacent an internal antenna  8  of an electronic device  10  when the device is enclosed within the case  2 . The capacitively coupling element  4  and the device&#39;s internal antenna  8  form the plates of a capacitor and couple to the internal antenna  8  of the electronic device  10  to the element  4  of the device  10 . A shielding portion  7 , also constructed from a conductive foil, can be constructed to minimize any undesirable coupling to the coupling element  4  from electronics other than the antenna  8  in the device  10 . The coupling element  4  can be electrically connected to an extendable antenna  12  that can be retracted into the spine  14  of the case  2  for additional enhanced reception performance. The antenna  12  can also be adjustable such that it can be twisted, bent or rotated to maximize the reception boosting functionality of the case. 
         [0017]    An external connector  9  on the case  2  allows an external power source to be coupled to the device  10  through the case  2 . A mating connector  11  on the interior of the case  2  couples to a corresponding connector  13  on the device. Power received from the connector  9  can thus be provided to the device when the device is contained within the case  2 . The case  2  can also contain power conversion circuitry such that an incompatible power supply can be coupled to the device  10  through the case  2 . 
         [0018]    Referring now to  FIG. 2 , an illustration of a device case constructed in accordance with an alternative embodiment of the present invention is shown. The device case is constructed from two faces or panels  20  and  22  that snap together to enclose the portable electronic device  24 . An opening  28  in the front panel  20  allows the controls  30  of the device to be accessed through the panel  20 . In addition, recesses  32  in each panel  20  and  22  form openings when the panels  20  and  22  are joined such that inputs and outputs of the device  24  can be accessed while the device enclosed within the panels  20  and  22 . An electromagnetic coupling element  26  is positioned on the appropriate case panel  20  and  22  such that it is adjacent the internal antenna of the device  24  when the device  24  is enclosed within the case. The coupling element  26  couples received signals to the internal antenna of the device  24  thereby improving the device&#39;s reception. 
         [0019]    In many situations, the coupling element  26  alone will provide enough of a boost in reception for the device  24 . However, the coupling element  26  can also be connected to an antenna and signal booster  38  to further improve the reception of the device if desired as described in more detail herein. The antenna and signal booster  38  can be constructed on a single chip that receives and amplifies the desired radio frequency signal. The amplified signal is then connected to the coupling element  26  which couples the signal to the internal antenna of the device  24 . The reception properties of the antenna and signal booster  38  are selected to correspond to the frequencies being received by the device for which the case is designed. This allows for better reception improvement than that provided by prior non-customized signal boosters. 
         [0020]    Different coupling elements  26  can be positioned on the back face  22  to maximize coupling with the internal antennas of different types of electronic devices  24 . If a conductive foil is used, the foil should be placed as close as possible to the location of the internal antenna of the device  24 . The element  26  may be constructed from an adhesive pad that can be repositioned on the case panel  22 , by a user or factory personnel, such that a single case design can accommodate different types of devices  24 . In addition, the element  26  is preferably shaped to correspond to a profile of the internal antenna of the device  24 . 
         [0021]    For devices having a plastic or dielectric covered external stub antenna  36 , a coupling element in the form of a conductive tube constructed from opposing halves  34  on the case panels  20  and  22 . These types of antennas are commonly found on cellular phones. The conductive tube  34 , the device antenna  36  and the antenna&#39;s covering form a capacitor that couples signals received by the conductive tube  34 , and any antenna or signal booster  38  to which it is connected, to the antenna  36  of the device  24 . Due to the complex electromagnetics involved, the most suitable coupling element  26  configuration for a particular type of device  24  is most easily determined experimentally on a case by case basis. Since the case is already being designed for a particular type of device, this type of custom configuration is relatively easy to incorporate into the case&#39;s design phase. 
         [0022]    A capacitive coupling element allows a signal boosting case to be designed for almost any pre-existing device. However, an inductive coupler, such as circular wire coil, may be used instead of a conductive tube  34  to inductively couple the signal booster  38  to the antenna  36  of the device  24 . Inductive coupling performs best when the device is purposely designed to receive an inductively coupled reception signal from a specially designed case since the device may not have an antenna design that is receptive to inductive coupling. In an inductively coupled embodiment, an inductive coupler is positioned in the device such that it can couple to an inductive coupler in the case. This allows the case to inductively transfer a boosted reception signal to the case. 
         [0023]    Referring now to  FIG. 3 , an illustration of a device case constructed in accordance with another embodiment of the present invention is shown. The case  70  is a pocket style case that includes an opening  72  at the top that allows the electronic device to be inserted into the case. A signal boosting coupling element  74  is positioned on a surface of the case. The element  74  is positioned on the case such that it is adjacent the antenna of device when the device is inserted into the case  70 . This is easily accomplished since the case  70  must already be designed to accommodate a particular type or class of device. The case  70  includes openings or windows  76  that allow the controls and display of the device to be accessed when the device is held in the case  70 . A shielding portion  78  may be included on the case  70  to prevent certain undesirable device electronics from coupling to the coupling element  74  of the device. 
         [0024]    Referring now to  FIG. 4 , an accessory  90  for a device  94  constructed in accordance with an embodiment of the present invention is shown. The accessory is constructed in the form of an existing device housing panel  92 , such as a battery cover. The existing device panel  92  is removed and replaced with accessory  90 . The accessory  90  includes a signal boosting element  96  that couples to an internal antenna of the device  94  when the existing panel  92  is replaced with the accessory  90 . This allows an aftermarket signal boosting accessory  90  to be designed for a device  94  that can be incorporated into the device in an invisible manner that does not affect the ascetics or portability of the device. 
         [0025]    Referring now to  FIG. 5 , a block diagram of a signal boosting case  50  constructed in accordance with an embodiment of the present invention is shown. The case  50  has an antenna  56  that is adapted to receive or transmit the frequencies utilized by the device for which the case  50  is designed. A signal amplifier  54  receives a signal from the antenna  56  and produces an amplified signal that is applied to the coupling element  52  of the case  50 . The signal amplifier  54  can be constructed on a single board computer and include a microcontroller if desired. The aligned coupling element  52  couples the signals received from the amplifier  54  to the device that is positioned in the case  50 . The aligned coupling element  52  is positioned within the case to maximize coupling between the coupling element  52  and device antenna. The signal amplifier  54  can be constructed on a single board computer and include a microcontroller if desired. 
         [0026]    A power supply  62  such as a rechargeable battery is included in the case  50  to power the amplifying circuitry. An external power connection  60  is used to charge the power supply  62  and provide power to the device when it is held in the case  50  through a device interface  58 . A shielding portion  64  may be provided on selected case  50  surfaces to prevent undesirable electronics in the device from coupling to the coupling element  52 . 
         [0027]    While the embodiments of the present invention have been primarily described with respect to boosting the reception capabilities of a device, those skilled in the art will appreciate that they can also be used to boost the transmission capabilities of a device. 
         [0028]    Although there have been described particular embodiments of the present invention of a new and useful RECEPTION BOOSTING ACCESSORY, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims.