Patent Publication Number: US-2020295459-A1

Title: Antenna for wireless communications integrated in electronic device

Description:
BACKGROUND 
     Field 
     The present application relates generally to antennas of electronic devices for wireless communications, and more particularly to antennas of implantable and non-implantable medical devices for wireless communications. 
     Description of the Related Art 
     Various electronic devices, e.g., implantable and non-implantable medical devices, include one or more antennas for wireless communication between the electronic device and other components of the electronic system. 
     SUMMARY 
     In one aspect disclosed herein, an apparatus is provided which comprises a housing and a circuit. The circuit comprises an inductor and at least one capacitor in electrical communication with the inductor. The circuit has a resonance frequency and bounds a non-electrically-conductive region of the housing. The circuit is configured to be operable as an antenna. 
     In another aspect disclosed herein, an apparatus is provided which comprises an electrically conductive layer, a dielectric region, and at least one capacitor. The dielectric region is within the electrically conductive layer. The at least one capacitor is in electrical communication with the electrically conductive layer to form a circuit having a resonance frequency and configured to be operable as an antenna. 
     In still another aspect disclosed herein, a method is provided which comprises wirelessly receiving a first plurality of electromagnetic signals at an electrically conductive structure of an electronic device. The electrically conductive structure circumscribes a non-electrically-conductive material, and the electrically conductive structure has a resonance frequency. The method further comprises resonantly coupling the first plurality of electromagnetic signals with the electrically conductive structure. The method further comprises generating a first plurality of electrical signals in response to the first plurality of electromagnetic signals. The method further comprises operating the electronic device in response to the first plurality of electrical signals. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments are described herein in conjunction with the accompanying drawings, in which: 
         FIGS. 1A and 1B  schematically illustrate top views of portions of two example apparatus in accordance with certain embodiments described herein; 
         FIGS. 2A-2D  schematically illustrate perspective views of four example slab-shaped portions of the housing in accordance with certain embodiments described herein; 
         FIG. 3A  schematically illustrates a top view of an example portion of an apparatus in accordance with certain embodiments described herein; 
         FIG. 3B  schematically illustrates a perspective view of an example slab-shaped portion of an apparatus in which the dielectric region comprises a cavity comprising air in accordance with certain embodiments described herein; 
         FIG. 4  schematically illustrates an example configuration in which an electronic device comprises an electrically conductive structure circumscribing a non-electrically-conductive material in accordance with certain embodiments described herein; 
         FIG. 5A  is a flow diagram of an example method in accordance with certain embodiments described herein; 
         FIG. 5B  is a flow diagram of another example method in accordance with certain embodiments described herein; 
         FIGS. 6A and 6B  schematically illustrate a top view and a perspective view, respectively, of an example portion of an apparatus in accordance with certain embodiments described herein; 
         FIGS. 7A and 7B  schematically illustrate a top view and a perspective view, respectively, of another example portion of an apparatus in accordance with certain embodiments described herein; 
         FIGS. 8A and 8B  schematically illustrate a top view and a perspective view, respectively, of another example portion of an apparatus in accordance with certain embodiments described herein; and 
         FIG. 9  schematically illustrates a perspective view of an example portion of an apparatus in accordance with certain embodiments described herein. 
     
    
    
     DETAILED DESCRIPTION 
     Certain embodiments described herein provide a cavity resonator that is configured to be operable as an antenna for wireless communications, with the cavity resonator located within a housing of an electronic device (e.g., a medical device, an auditory prosthesis, a component of an auditory prosthesis, a battery) or within an electrically conductive layer of the electronic device. The cavity resonator comprises a circuit comprising an inductor (e.g., an electrically conductive portion of the housing) and at least one capacitor in electrical communication with the inductor. The circuit has a resonance frequency and bounds a non-conductive region of the housing (e.g., an air-filled cavity within the electrically conductive portion of the housing), with the cavity extending to an opening at a surface of the housing and the at least one capacitor extending across the opening. Certain such embodiments advantageously provide an inexpensive antenna that is smaller than conventional on-board antennas and has less rigid constraints regarding the space surrounding the antenna, which can facilitate fabrication of smaller electronic devices. For example, a conventional 2.4 GHz chip antenna often utilizes a certain volume (e.g., about 1 cm 3 ) that is free from metal or other conductive materials, and this feature can represent a constraint to miniaturizing the electronic device containing the chip antenna. Certain embodiments described herein permit the volume dedicated to the antenna to be significantly smaller (e.g., by about 5-10% or more) while providing sufficient antenna performance. 
       FIGS. 1A and 1B  schematically illustrate top views of portions of two example apparatus  100  in accordance with certain embodiments described herein. The apparatus  100  comprises a housing  110  and a circuit  120  comprising an inductor  122  and at least one capacitor  124  in electrical communication with the inductor  122 . The circuit  120  has a resonance frequency, is bounding a non-conductive region  116  of the housing  110 , and is configured to be operable as an antenna. 
     In certain embodiments, the apparatus  100  comprises an electronic device selected from the group consisting of: a medical device, an auditory prosthesis, a hearing aid, a cochlear implant system, a component of an auditory prosthesis, a sound processor of an auditory prosthesis, an actuator of an auditory prosthesis, a magnetic coupler of an auditory prosthesis, a microphone of an auditory prosthesis, a battery, and a rechargeable battery. For example, the apparatus  100  can be an implantable component of an auditory prosthesis or a non-implantable component of an auditory prosthesis. 
     In certain embodiments, the housing  110  comprises one or more portions which form an enclosure containing some or all of the other components of the apparatus  100 . Some or all of the portions of the housing  110  in certain embodiments comprise a non-electrically-conductive material (e.g., a dielectric material, ceramic, plastic, polymer), while some or all of the portions of the housing  110  in certain other embodiments comprise an electrically conductive material (e.g., metal). For example, as schematically illustrated by  FIG. 1B , a non-electrically-conductive portion  112  of the housing  110  can comprise a non-electrically-conductive material and an electrically conductive portion  114  of the housing  110  can comprise an electrically conductive material which borders (e.g., extends along a boundary of) a non-electrically-conductive region  116  of the housing  110 . In certain embodiments, during operation of the apparatus  100 , the electrically conductive portion  112  of the housing  110  is at an electrical reference (e.g., ground) voltage of the apparatus  100 . 
     In both  FIGS. 1A and 1B , the non-electrically-conductive region  116  is within the inductor  122 . In  FIG. 1A , the non-electrically-conductive region  116  is within the electrically conductive portion  114  of the housing  110 , and in  FIG. 1B , the non-electrically-conductive region  116  is within the inductor  122 , and the inductor  122  is within the non-electrically-conductive portion  112  of the housing  110 . 
     In certain embodiments, the inductor  122  comprises at least an electrically conductive portion of the housing  110  (e.g., the electrically conductive portion  114  schematically illustrated by FIGS. lA and  1 B) having an inductance L and bordering (e.g., extending along a boundary of) the non-electrically-conductive region  116  of the housing  110 . For example, the inductor  122  can comprise some or all of the electrically conductive portion  114  of the housing  110  (e.g., all of the electrically conductive material as schematically illustrated in  FIG. 1B ; a portion of the electrically conductive material as schematically illustrated in  FIG. 1A  with the portion denoted as being between a dashed line and the non-electrically-conductive region  116 ). The electrically conductive portion  114  of the housing  110  can comprise a portion of at least one surface  118  of the housing  110 . The inductance L can be dependent on the size, shape, and configuration of the electrically conductive portion  114  (e.g., longer sides of the electrically conductive portion  144  can correspond to higher inductances). 
     In certain embodiments, the non-electrically-conductive region  116  of the housing  110  comprises a solid dielectric material (e.g., ceramic, plastic, polymer), while in certain other embodiments, the non-electrically conductive region  116  of the housing  110  comprises a cavity comprising air. Since the non-electrically-conductive region  116  comprises a portion of the housing  110 , a shape of the non-electrically-conductive region  116  can generally conform to the shape of the housing  110 . For example, in certain embodiments in which the non-electrically-conductive region  116  is within a planar portion of the housing  110 , the non-electrically-conductive region  116  is also planar. In certain embodiments in which the non-electrically-conductive region  116  is within a non-planar (e.g., curved) portion of the housing  110 , the non-electrically-conductive region  116  is also non-planar (e.g., curved). 
     The at least one capacitor  124  of certain embodiments comprises one or more electrical components having a capacitance C (e.g., about 5-10 pF) and being in electrical communication with the inductor  122 . The at least one capacitor  124  can be located at the surface  118  of the housing  110 , as schematically illustrated by  FIGS. 1A and 1B . For example, the at least one capacitor  124  can have a first end in electrical communication with a first portion of the inductor  122  at the surface  118  and a second end in proximity to a second portion of the inductor  122  at the surface  118 , with the at least one capacitor  124  bordering (e.g., extending along a boundary of) the non-electrically-conductive region  116 , such that the circuit  120  comprising the inductor  122  and the at least one capacitor  124  is bounding (e.g., encircling; circumscribing) the non-electrically-conductive region  116  of the housing  110 . In certain embodiments, the circuit  120  further comprises one or more electrical conduits (not shown) that are configured to transmit electrical signals ΔV s  (e.g., relative to a reference voltage such as a ground voltage) between the circuit  120  and antenna circuitry (not shown) of the apparatus  100 . For example, the one or more electrical conduits can comprise a pair of electrical conduits (e.g., a coaxial cable), wherein a signal electrical conduit (e.g., the signal conduit of the coaxial cable) is in electrical communication with the second end of the at least one capacitor  124  and a reference electrical conduit (e.g., the shielding conduit of the coaxial cable) is in electrical communication with the second portion of the inductor  22  at the surface  118 . In certain embodiments in which the non-electrically-conductive region  116  comprises a cavity comprising air, the non-electrically-conductive region  116  further comprises an opening at the surface  118  of the housing  110 , and the at least one capacitor  124  extends across the opening. In certain embodiments, the at least one capacitor  124  is configured for the function of the circuit  120  as an antenna, and the apparatus  100  further comprises other electrical components (e.g., antenna circuitry) that are configured for other purposes (e.g., signal matching). 
       FIGS. 2A-2D  schematically illustrate perspective views of four example slab-shaped portions  200  of the housing  110  in accordance with certain embodiments described herein. Each of the slab-shaped portions  200  of  FIGS. 2A-2D  has a non-electrically-conductive region  116  comprising a cavity  210  comprising air in accordance with certain embodiments described herein. The cavity  210  can comprise an opening  212  at a surface  118  of the housing  110 , and the at least one capacitor  124  can extend along the opening  212 , as schematically illustrated by  FIGS. 2A-2D . While  FIGS. 2A-2D  schematically illustrate examples in which the non-electrically-conductive region  116  comprises a cavity  210  comprising air, in certain other embodiments, the non-electrically-conductive region  116  comprises a solid non-electrically-conductive material (e.g., ceramic, plastic, polymer). Also, while  FIGS. 2A-2D  schematically illustrate generally planar, rectilinear configurations of the housing  110  and other portions of the apparatus  100  (e.g., one or more of the non-electrically-conductive portion  112 , electrically conductive portion  114 , non-electrically-conductive region  116 , surface  118 , circuit  120 , inductor  122 , at least one capacitor  124 , cavity  210 , and opening  212 ), other configurations compatible with certain embodiments described herein have non-planar (e.g., curved) and/or non-rectilinear (e.g., curved, irregular) configurations of the housing  110  and/or one or more of the other portions of the apparatus  100 . For example, one or more of the housing  110  and the other portions of the apparatus  100  can have a configuration, shape, and/or dimensions that are configured to facilitate operation of the apparatus  100  as an antenna having a predetermined radiative pattern for communications of electromagnetic signals having a predetermined frequency range. 
       FIG. 2A  schematically illustrates an example portion  200  of the housing  110  corresponding to the example housing  110  shown schematically in the top view of  FIG. 1A , and  FIG. 2B  schematically illustrates an example portion  200  of the housing  110  corresponding to the example housing  110  shown schematically in the top view of  FIG. 1B . In both  FIGS. 2A and 2B , the cavity  210  extends to a first surface  214  of the housing  110  and to a second surface  216  of the housing  110  opposite to the first surface  214 . 
       FIG. 2C  schematically illustrates an example portion  200  of the housing  110  in which the cavity  210  extends to the first surface  214  of the housing  110  but does not extend to the opposite second surface  216  of the housing  110 .  FIG. 2D  schematically illustrates an example portion  200  of the housing  110  in which the cavity  210  does not extend to either the first surface  214  of the housing  110  or the opposite second surface  216  of the housing  110 . 
     In each of  FIGS. 2A-2D , the non-electrically-conductive region  116  is within the housing  110 . For example, in each of  FIGS. 2A-2B , the cavity  210  is within the electrically conductive portion  114  of the housing  110 . For another example, in each of  FIGS. 2C-2D , the cavity  210  is within the electrically conductive portion  114  of the housing  110 , and the electrically conductive portion  114  of the housing  110  is within a non-electrically-conductive portion  112  of the housing  110 . 
     The circuit  120  comprising the inductor  122  and the at least one capacitor  124  can be considered to be an “LC” or “RLC” resonant circuit having a resonance frequency f 0 =1/2√{square root over (LC)}, with f 0  in units of hertz, L in units of henrys, and C in units of farads. In certain embodiments (e.g., in which the non-electrically-conductive region  116  comprises a cavity comprising air), the circuit  120  can be considered to be a “cavity resonator.” 
     In certain embodiments, the inductance L and the capacitance C of the circuit  120  are selected such that the resonance frequency is in a range between 2 GHz and 6 GHz (e.g., compatible with Bluetooth® wireless communication schemes). Other ranges of resonance frequencies and other wireless communication schemes are also compatible with certain embodiments described herein. The circuit  120  can be configured to be operable as an antenna (e.g., by transmitting and/or receiving electromagnetic signals, at least some of which have a frequency equal to or within  10 % of the resonance frequency). For example, the circuit  120  can be configured to wirelessly transmit electromagnetic signals to a controller spaced from the housing  110 , to receive wirelessly transmitted electromagnetic signals from the controller, or both. In certain such embodiments, the controller is spaced from the housing  110 , and is configured to wirelessly transmit electromagnetic signals to the circuit  120 , to receive wirelessly transmitted electromagnetic signals from the circuit  120 , or both. 
     As described herein, in certain embodiments, the circuit  120  is formed within the housing  110  of an apparatus  100 . The inductor  122  can comprise an electrically conductive portion  114  of the housing  110  which provides the inductance for the circuit  120 . For example, as schematically illustrated by  FIGS. 1A and 2A-2B , the inductor  122  can comprise a portion of an electrically conductive layer (e.g., slab, plate). For another example, as schematically illustrated by  FIGS. 1B and 2C-2D , the inductor  122  can comprise an electrically conductive material between and bordering the non-electrically-conductive region  116  and a non-electrically-conductive portion  112  of a non-electrically-conductive layer (e.g., slab, plate). 
     In certain other embodiments, the circuit  120  is formed within an electrically conductive layer (e.g., slab, plate) of the apparatus  100  without being formed within the housing  110  of the apparatus  100 .  FIG. 3A  schematically illustrates a top view of an example portion of an apparatus  300  in accordance with certain embodiments described herein. The apparatus  300  comprises an electrically conductive layer  310  (e.g., slab, plate) and a dielectric region  320  within the electrically conductive layer  310 . The apparatus  300  further comprises at least one capacitor  330  in electrical communication with the electrically conductive layer  310  to form a circuit  340  having a resonance frequency and configured to be operable as an antenna.  FIG. 3B  schematically illustrates a perspective view of an example slab-shaped portion of an apparatus  300  in which the dielectric region  320  comprises a cavity  350  comprising air in accordance with certain embodiments described herein. 
     The apparatus  300  schematically illustrated in  FIGS. 3A-3B  can be similar to the apparatus  100  schematically illustrated in  FIG. 1A  and  FIGS. 2A-2B  (e.g., the apparatus  300  having one or more components with the same or similar attributes as corresponding components of the apparatus  100 ), although the portion of the apparatus  300  of  FIGS. 3A-3B  can be in other components of the apparatus  300  besides the housing  110 . For example, in certain embodiments, the electrically conductive layer  310  (e.g., which can be a portion of the housing  110  or a portion of another component of the apparatus  300  besides the housing) has one or more attributes (e.g., surface  312 , first surface  314 , second opposite surface  316 ) as described herein with regard to the electrically conductive portion  114  and/or the inductor  122  of  FIGS. 1A and 2A-2B  (e.g., surface  118 , first surface  214 , second opposite surface  216 ). For another example, in certain embodiments, the dielectric region  320  has one or more attributes (e.g., cavity  350 , opening  352 ) as described herein with regard to the non-electrically-conductive region  116  of  FIGS. 1A and 2A-2B  (e.g., cavity  210 , opening  212 ). For still another example, in certain embodiments, the at least one capacitor  330  and/or the circuit  340  has one or more attributes as described herein with regard to the at least one capacitor  124  and/or the circuit  120  of  FIGS. 1A and 2A-2B . 
       FIG. 4  schematically illustrates an example configuration  400  in which an electronic device  410  comprises an electrically conductive structure  420  circumscribing a non-electrically-conductive material  430  in accordance with certain embodiments described herein. The electrically conductive structure  420  can be configured to be operable as an antenna, e.g., for wireless communications with a controller  440 , in accordance with certain embodiments described herein. 
     In certain embodiments, the electronic device  410  is selected from the group consisting of: a medical device, an auditory prosthesis, a hearing aid, a cochlear implant system, a component of an auditory prosthesis, a sound processor of an auditory prosthesis, an actuator of an auditory prosthesis, a magnetic coupler of an auditory prosthesis, a microphone of an auditory prosthesis, a battery, and a rechargeable battery. For example, the electronic device  410  can be an implantable component of an auditory prosthesis or a non-implantable component of an auditory prosthesis. 
     In certain embodiments (see, e.g.,  FIGS. 1A, 1B, and 2A-2D ), the electrically conductive structure  420  comprises a circuit  120  comprising an inductor  122  (e.g., an electrically conductive portion  114  of the housing  110 ) and at least one capacitor  124  in electrical communication with the inductor  122 , and the non-electrically-conductive material  430  circumscribed by the electrically conductive structure  420  comprises a non-electrically-conductive region  116  of the housing  110  bounded by the circuit  120 . In certain other embodiments (see, e.g.,  FIGS. 3A-3B ), the electrically conductive structure  420  comprises a circuit  340  comprising an electrically conductive layer  310  and at least one capacitor  330  in electrical communication with the electrically conductive layer  310 , and the non-electrically-conductive material  430  circumscribed by the electrically conductive structure  420  comprises a dielectric region  320  within the electrically conductive layer  310 . While the configuration  400  is described herein in relation to the structures of  FIGS. 1A-1B, 2A-2D, and 3A-3B , other configurations and structures may be utilized as well in accordance with certain embodiments described herein. 
     In certain embodiments, the controller  440  comprises a second electronic device spaced from the electronic device  410  and configured to generate control signals and to wirelessly transmit the control signals to the electronic device  410 . For example, in certain embodiments in which the electronic device  410  comprises a component of an auditory prosthesis (e.g., battery; sound processor), the controller  440  comprises a remote control unit for wirelessly controlling certain operation of the component of the auditory prosthesis, and the electronic device  410  is configured to respond to the control signals by adjusting or initiating certain operational states or operational parameters (e.g., stimulation rate; sound processing; battery life). The controller  440  of certain embodiments comprises a processor  442  configured to generate control signals for the electronic device  410  and antenna circuitry  444  in electrical communication with the processor  442  and configured to wirelessly transmit the control signals as a first plurality of electromagnetic signals  446  to the electronic device  410 . 
       FIG. 5A  is a flow diagram of an example method  500  in accordance with certain embodiments described herein. In an operational block  510 , the method  500  comprises wirelessly receiving a first plurality of electromagnetic signals  446  at an electrically conductive structure  420  (e.g., circuit  120 ; circuit  340 ) of an electronic device  410 . The electrically conductive structure  420  circumscribes a non-electrically-conductive material  430  and has a resonance frequency. The electrically conductive structure  420  comprises a portion of a housing of the electronic device  410  or a portion of an electrically-conductive layer of the electronic device  410 . In an operational block  520 , the method  500  further comprises resonantly coupling the first plurality of electromagnetic signals  446  with the electrically conductive structure  420 . In an operational block  530 , the method  500  further comprises generating a first plurality of electrical signals in response to the first plurality of electromagnetic signals  446 . In an operational block  540 , the method  500  further comprises operating the electronic device  410  in response to the first plurality of electrical signals. While the example method  500  is described herein in relation to the example structures schematically illustrated by  FIGS. 1A, 1B, 2A-2D, 3A-3B, and 4 , other structures are also compatible with certain embodiments described herein. 
     In certain embodiments, the first plurality of electromagnetic signals  446  are generated by the controller  440 , which is spaced from the electronic device  410 , and are wirelessly transmitted to the electrically conductive structure  420  prior to wirelessly receiving the first plurality of electromagnetic signals  446  at the electrically conductive structure  420  in the operational block  410 . The first plurality of electromagnetic signals  446  can comprise control information to be used to control one or more operational functions of the electronic device  410 . By transmitting the first plurality of electromagnetic signals from the controller  440  to the electrically conductive structure  420 , certain embodiments wirelessly communicate control information to the electronic device  410  for controlling certain operation of the electronic device  410  (e.g., stimulation rate; sound processing; battery life; other operations of an auditory prosthesis). 
     Upon receiving the first plurality of electromagnetic signals  446 , in the operational block  520 , the first plurality of electromagnetic signals  446  are resonantly coupled with the electrically conductive structure  420  of the electronic device  410  (e.g., with the circuit  120 ; with the circuit  340 ). For example, the resonance frequency of the electrically conductive structure  420  can be in a predetermined range (e.g., in a range between 2 GHz and 6 GHz; in a range compatible with Bluetooth® wireless communication schemes), and the first plurality of electromagnetic signals  446  resonantly coupled with the electrically conductive structure  420  can have at least one frequency compatible with resonantly coupling with the electrically conductive structure  420  (e.g., within the predetermined range; equal to or within  10 % of the resonance frequency). 
     In the operational block  530 , a first plurality of electrical signals can be generated in response to the first plurality of electromagnetic signals  446  received at the electrically conductive structure  420 . For example, the electrically conductive structure  420  can be in electrical communication with antenna circuitry of the electronic device  410  that is configured to transform (e.g., demodulate; decode) electromagnetic signals received by the electrically conductive structure  420  into electrical signals to be sent to one or more other components of the electronic device  410 . In the operational block  540 , these one or more other components of the electronic device  410  can be operated in response to the first plurality of electrical signals. 
       FIG. 5B  is a flow diagram of another example method  500  in accordance with certain embodiments described herein. In addition to the operational blocks  510 - 540  disclosed herein, the method  500  can further comprise, in an operational block  550 , generating a second plurality of electrical signals. For example, a processor or other circuitry of the electronic device  410  can generate a second plurality of electrical signals that are indicative of operational states or operational parameters of the electronic device  410  (e.g., stimulation rate; sound processing; battery life; other aspects of operation of an auditory prosthesis). The method  500  can further comprise, in an operational block  560 , using the electrically conductive structure  420  to generate a second plurality of electromagnetic signals in response to the second plurality of electrical signals. For example, antenna circuitry of the electronic device  410  can receive the second plurality of electrical signals and can drive the electrically conductive structure  420  (e.g., modulate; encode) in response to the second plurality of electrical signals so as to generate the second plurality of electromagnetic signals. Driving the electrically conductive structure  420  can comprise modulating (e.g., encoding) a carrier signal to include information to be transmitted by the second plurality of electromagnetic signals. For example, by transmitting the second plurality of electromagnetic signals from the electrically conductive structure  420  to the controller  440  and receiving the second plurality of electromagnetic signals at the controller  440 , certain embodiments wirelessly communicate the operational states or operational parameters of the electronic device  410  to the controller  440  (e.g., stimulation rate; sound processing; battery life; other operations of an auditory prosthesis). 
       FIGS. 6A and 6B  schematically illustrate a top view and a perspective view, respectively, of an example portion of an apparatus  600  in accordance with certain embodiments described herein. The apparatus  600  (e.g., battery; sound processor; component of an auditory prosthesis) comprises an electrically conductive layer  310  (e.g., an electrically conductive portion  114  of a housing  110 ), a dielectric region  320  (e.g., a cavity  210  comprising air) within the electrically conductive layer  310 , and at least one capacitor  330  in electrical communication with the electrically conductive layer  310  to form a circuit  340 . 
     As schematically shown in  FIGS. 6A and 6B , the circuit  340  is at a corner of the housing  110  of the apparatus  600 , with the housing  110  comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. In certain other embodiments, the circuit  340  is at a corner of another electrically conductive portion of the apparatus  600 , with the portion comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. 
     The electrically conductive layer  310  comprises a first edge  610  and a second edge  620 , with a portion of the first edge  610  and a portion of the second edge  620  bounding two sides of the dielectric region  320  (e.g., the cavity  210 ). A third edge  630  of the electrically conductive layer  310  bounds a third side of the dielectric region  320 , and the at least one capacitor  330  bounds a fourth side of the dielectric region  320 . The first edge  610 , second edge  620 , and third edge  630  can be in electrical communication with one another, and during operation of the apparatus  600 , can be at an electrical reference (e.g., ground) voltage of the apparatus  600 . The portion of the first edge  610 , the portion of the second edge  620 , and the third edge  630  can form an inductor  122  which is in electrical communication with the at least one capacitor  330  to form a circuit  120  bounding the dielectric region  320  (e.g., a non-electrically-conductive region of the housing  110 ; cavity  210 ). For example, a portion of the apparatus  600  can have the shape of a truncated corner of a rectangular parallelepiped, with the first edge  610  and the second edge  620  extended outward towards one another, and with the at least one capacitor  330  extending between, and in electrical communication with, the extended ends of the first edge  610  and the second edge  620 . Other shapes and/or configurations of the cavity  210 , circuit  340 , first edge  610 , second edge  620 , and third edge  630  are also compatible with certain embodiments described herein. 
     In certain embodiments, the apparatus  600  comprises a non-electrically-conductive solid material  640  which serves as a substrate to mechanically support the at least one capacitor  330 , while in certain other embodiments, the non-electrically-conductive solid material  640  is absent, and the at least one capacitor  330  is self-supporting and extends across an opening of the cavity  210  between the portion of the first edge  610  and the portion of the second edge  620  (e.g., the at least one capacitor  330  comprises a dielectric strip extending across the opening of the cavity  210  and supporting the at least one capacitor  330 ). The apparatus  600  of certain embodiments further comprises an electrical conduit  650  (e.g., wire; cable) in electrical communication with the at least one capacitor  330  and antenna circuitry  670  (e.g., transmitter; receiver; transceiver) of the apparatus  600 . For example, the electrical conduit  650  can comprise a coaxial cable having a signal conduit and a shielding conduit, with one of the signal conduit and the shielding conduit in electrical communication with the at least one capacitor  330 , and the other of the signal conduit and the shielding conduit in electrical communication with the inductor  122 . The electrical conduit  650  can be configured to transmit electrical signals from the antenna circuitry to the circuit  340  and/or from the circuit  340  to the antenna circuitry. 
       FIGS. 7A and 7B  schematically illustrate a top view and a perspective view, respectively, of another example portion of an apparatus  700  in accordance with certain embodiments described herein. The apparatus  700  (e.g., battery; sound processor; component of an auditory prosthesis) comprises an electrically conductive layer  310  (e.g., an electrically conductive portion  114  of a housing  110 ), a dielectric region  320  (e.g., a cavity  210  comprising air) within the electrically conductive layer  310 , and at least one capacitor  330  in electrical communication with the electrically conductive layer  310  to form a circuit  340 . 
     As schematically shown in  FIGS. 7A and 7B , the circuit  340  is on a substrate  710  comprising a non-electrically-conductive material (e.g., dielectric; ceramic; plastic; polymer) and is configured to be at a corner of a component of the apparatus  700  (e.g., the housing  110  of the apparatus  700 ). In certain embodiments, the substrate  710  and circuit  340  are integral with the other portions of the component of the apparatus  700 , while in certain other embodiments, the substrate  710  and circuit  340  are a portion of the component of the apparatus  700  that is configured to be attachable to and detachable from the rest of the apparatus  700  (e.g., at a corner of the apparatus  700 ) without damage to the substrate  710 , the circuit  340 , or the rest of the apparatus  700 . For example, the substrate  710  can have a shape configured to fit onto a portion of the apparatus  700  having the shape of a truncated corner of a rectangular parallelepiped. Other shapes and/or configurations of the substrate  710 , cavity  210 , circuit  340 , first electrically conductive surface  720 , second electrically conductive surface  730 , and third electrically conductive surface  740  are also compatible with certain embodiments described herein. 
     The electrically conductive layer  310  comprises a first electrically conductive surface  720 , a second electrically conductive surface  730 , and a third electrically conductive surface  740 , with the first electrically conductive surface  720 , second electrically conductive surface  730 , and third electrically conductive surface  740  on the substrate  710  (e.g., deposited onto respective portions of the substrate  710 ) and bounding three sides of the dielectric region  320  (e.g., a non-electrically-conductive region of the housing  110 ; cavity  210 ). The at least one capacitor  330  bounds a fourth side of the dielectric region  320 . The first electrically conductive surface  720 , second electrically conductive surface  730 , and third electrically conductive surface  740  can be in electrical communication with one another, and during operation of the apparatus  700 , can be at an electrical reference (e.g., ground) voltage of the apparatus  700 . The first electrically conductive surface  720 , second electrically conductive surface  730 , and third electrically conductive surface  740  can form an inductor  122  which is in electrical communication with the at least one capacitor  330  to form a circuit  120  bounding the dielectric region  320  (e.g., the cavity  210 ). 
     In certain embodiments, as schematically illustrated by  FIGS. 7A and 7B , a non-electrically-conductive portion  750  of the substrate  710  mechanically supports the at least one capacitor  330 , while in certain other embodiments, the portion  750  of the substrate  710  is absent, and the at least one capacitor  330  is self-supporting and extends across an opening of the cavity  210  between the portion of the first electrically conductive surface  720  and the portion of the second electrically conductive surface  730  (e.g., the at least one capacitor  330  comprises a dielectric strip extending across the opening of the cavity  210  and supporting the at least one capacitor  330 ). The apparatus  700  of certain embodiments further comprises an electrical conduit  760  (e.g., wire; cable) in electrical communication with the at least one capacitor  330  and antenna circuitry  770  (e.g., transmitter; receiver; transceiver) of the apparatus  700 . For example, the electrical conduit  760  can comprise a coaxial cable having a signal conduit and a shielding conduit, with one of the signal conduit and the shielding conduit in electrical communication with the at least one capacitor  330  and the other of the signal conduit and the shielding conduit in electrical communication with the inductor  122 . The electrical conduit  760  can be configured to transmit electrical signals from the antenna circuitry to the circuit  340  and/or from the circuit  340  to the antenna circuitry. 
       FIGS. 8A and 8B  schematically illustrate a top view and a perspective view, respectively, of another example portion of an apparatus  800  in accordance with certain embodiments described herein. The apparatus  800  (e.g., battery; sound processor; component of an auditory prosthesis) comprises an electrically conductive layer  310  (e.g., an electrically conductive portion  114  of a housing  110 ), a dielectric region  320  (e.g., a cavity  210  comprising air) within the electrically conductive layer  310 , and at least one capacitor  330  in electrical communication with the electrically conductive layer  310  to form a circuit  340 . 
     As schematically shown in  FIGS. 8A and 8B , the circuit  340  is at a side of the housing  110  of the apparatus  800  (e.g., a flat side), with the housing  110  comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. In certain other embodiments, the circuit  340  is at a side of another electrically conductive portion of the apparatus  800 , with the portion comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. 
     The electrically conductive layer  310  comprises a first surface  810  at an edge  812  of the housing  110  and a second surface  820  defining a cavity  210  and an opening  212  of the cavity  210  at the edge  812 , with the second surface  820  bounding a portion of the dielectric region  320  (e.g., the cavity  210 ). The at least one capacitor  330  extends across the opening  212  and bounds a remaining portion of the dielectric region  320 . The first surface  810  and the second surface  820  can be in electrical communication with one another, and during operation of the apparatus  800 , can be at an electrical reference (e.g., ground) voltage of the apparatus  800 . The second surface  820  can form an inductor  122  which is in electrical communication with the at least one capacitor  330  to form a circuit  120  bounding the dielectric region  320  (e.g., a non-electrically-conductive region of the housing  110 ; cavity  210 ). For example, as schematically illustrated in  FIGS. 8A and 8B , the cavity  210  can have a substantially circular shape, and with the at least one capacitor  330  extending across the opening  212  between, and in electrical communication with, a first portion of the first surface  810  and a second portion of the first surface  810 . Other shapes and/or configurations of the cavity  210 , circuit  340 , first surface  810 , second surface  820 , and edge  812  are also compatible with certain embodiments described herein. 
     In certain embodiments, the apparatus  800  comprises a non-electrically-conductive solid material  830  which serves as a substrate to mechanically support the at least one capacitor  330 , while in certain other embodiments, the non-electrically-conductive solid material  830  is absent, and the at least one capacitor  330  is self-supporting and extends across the opening  212  (e.g., the at least one capacitor  330  comprises a dielectric strip extending across the opening  212  and supporting the at least one capacitor  330 ). The apparatus  800  of certain embodiments further comprises an electrical conduit  840  (e.g., wire; cable) in electrical communication with the at least one capacitor  330  and antenna circuitry  870  (e.g., transmitter; receiver; transceiver) of the apparatus  800 . For example, the electrical conduit  840  can comprise a coaxial cable having a signal conduit and a shielding conduit, with one of the signal conduit and the shielding conduit in electrical communication with the at least one capacitor  330  and the other of the signal conduit and the shielding conduit in electrical communication with the inductor  122 . The electrical conduit  840  can be configured to transmit electrical signals from the antenna circuitry to the circuit  340  and/or from the circuit  340  to the antenna circuitry. 
       FIG. 9  schematically illustrates a perspective view of an example portion of an apparatus  900  in accordance with certain embodiments described herein. The apparatus  900  (e.g., battery; sound processor; component of an auditory prosthesis) comprises an electrically conductive layer  310  (e.g., an electrically conductive portion  114  of a housing  110 ), a dielectric region  320  (e.g., a cavity  210  comprising air) within the electrically conductive layer  310 , and at least one capacitor  330  in electrical communication with the electrically conductive layer  310  to form a circuit  340 . 
     As schematically shown in  FIG. 9 , the circuit  340  is at a side of the housing  110  of the apparatus  900  (e.g., a curved side), with the housing  110  comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. In certain other embodiments, the circuit  340  is at a side of another electrically conductive portion of the apparatus  900 , with the portion comprising an electrically conductive material (e.g., metal) and/or an electrically conductive surface. 
     As schematically illustrated by  FIG. 9 , the electrically conductive layer  310  comprises a first surface  910  at an edge  912  of the housing  110  and a second surface  920  defining a cavity  210  and an opening  212  of the cavity  210  at the edge  912 , with the second surface  920  bounding a portion of the dielectric region  320  (e.g., the cavity  210 ). As schematically illustrated by  FIG. 9 , the cavity  210  extends from a first surface  914  of the housing  110  to a second surface  916  opposite to the first surface  914 , and comprises an opening  212  at the edge  912  of the housing  110 . 
     In  FIG. 9 , the opening  212  has a long dimension and a short dimension, and the at least one capacitor  330  extends across the opening  212  along the short dimension. While the second surface  920  bounds a portion of the dielectric region  320  (e.g., the cavity  210 ), the at least one capacitor  330  bounds a remaining portion of the dielectric region  320 . During operation of the apparatus  900 , the first surface  910  and the second surface  920  can be at an electrical reference (e.g., ground) voltage of the apparatus  900 . The second surface  820  can form an inductor  122  which is in electrical communication with the at least one capacitor  330  to form a circuit  120  bounding the dielectric region  320  (e.g., a non-electrically-conductive region of the housing  110 ; cavity  210 ). For example, as schematically illustrated in  FIG. 9 , the at least one capacitor  330  extends across the opening  212  along the short dimension between, and in electrical communication with, a first portion of the first surface  910  and a second portion of the first surface  910 . Other shapes and/or configurations of the cavity  210 , opening  212 , circuit  340 , first surface  910 , second surface  920 , and edge  912  are also compatible with certain embodiments described herein. 
     In certain embodiments, the apparatus  900  comprises a non-electrically-conductive solid material  930  which serves as a substrate to mechanically support the at least one capacitor  330 , while in certain other embodiments, the non-electrically-conductive solid material  930  is absent, and the at least one capacitor  330  is self-supporting and extends across the opening  212 . The apparatus  900  of certain embodiments further comprises an electrical conduit  940  (e.g., wire; cable) in electrical communication with the at least one capacitor  330  and antenna circuitry  970  (e.g., transmitter; receiver; transceiver) of the apparatus  900 . For example, the electrical conduit  940  can comprise a coaxial cable having a signal conduit and a shielding conduit, with one of the signal conduit and the shielding conduit in electrical communication with the at least one capacitor  330  and the other of the signal conduit and the shielding conduit in electrical communication with the inductor  122 . The electrical conduit  940  can be configured to transmit electrical signals from the antenna circuitry to the circuit  340  and/or from the circuit  340  to the antenna circuitry. 
     It is to be appreciated that the embodiments disclosed herein are not mutually exclusive and may be combined with one another in various arrangements. 
     The invention described and claimed herein is not to be limited in scope by the specific example embodiments herein disclosed, since these embodiments are intended as illustrations, and not limitations, of several aspects of the invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in form and detail, in addition to those shown and described herein, will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the claims. The breadth and scope of the invention should not be limited by any of the example embodiments disclosed herein, but should be defined only in accordance with the claims and their equivalents. 
     Certain Embodiments 
     Certain embodiments are listed below. The following embodiments are presented for explanatory and illustrative purposes only. It will be appreciated that the foregoing description is not limited to the following embodiments. 
     Embodiment 1: An apparatus comprising: a housing; and a circuit comprising an inductor and at least one capacitor in electrical communication with the inductor, the circuit having a resonance frequency and bounding a non-electrically-conductive region of the housing, wherein the circuit is configured to be operable as an antenna. 
     Embodiment 2: The apparatus of Embodiment 1, wherein the apparatus comprises an electronic device selected from the group consisting of: a medical device, an auditory prosthesis, a hearing aid, a cochlear implant system, a component of an auditory prosthesis, a sound processor of an auditory prosthesis, an actuator of an auditory prosthesis, a magnetic coupler of an auditory prosthesis, a microphone of an auditory prosthesis, a battery, and a rechargeable battery. 
     Embodiment 3: The apparatus of Embodiment 1 or Embodiment 2, wherein the inductor comprises an electrically conductive portion of the housing, the non-electrically-conductive region within the electrically conductive portion. 
     Embodiment 4: The apparatus of Embodiment 3, wherein the non-electrically-conductive region is planar. 
     Embodiment 5: The apparatus of Embodiment 3, wherein the electrically conductive portion of the housing comprises a portion of at least one surface of the housing. 
     Embodiment 6: The apparatus of Embodiment 3, wherein, during operation of the apparatus, the electrically conductive portion of the housing is at an electrical reference voltage of the apparatus. 
     Embodiment 7: The apparatus of any of Embodiments 1 to 6, wherein the non-electrically-conductive region of the housing comprises a dielectric material selected from the group consisting of: air, ceramic, plastic, and polymer. 
     Embodiment 8: The apparatus of Embodiment 7, wherein the non-electrically-conductive region of the housing comprises a cavity comprising air and an opening at a surface of the housing, the at least one capacitor extending across the opening. 
     Embodiment 9: The apparatus of any of Embodiments 1 to 8, wherein the resonance frequency is in a range between 2 GHz and 6 GHz. 
     Embodiment 10: The apparatus of any of Embodiments 1 to 9, further comprising a controller spaced from the housing, the controller configured to wirelessly transmit electromagnetic signals to the circuit, to receive wirelessly transmitted electromagnetic signals from the circuit, or both. 
     Embodiment 11: An apparatus comprising: an electrically conductive layer; a dielectric region within the electrically conductive layer; and at least one capacitor in electrical communication with the electrically conductive layer to form a circuit having a resonance frequency and configured to be operable as an antenna. 
     Embodiment 12: The apparatus of Embodiment 11, wherein the apparatus comprises an electronic device selected from the group consisting of: a medical device, an auditory prosthesis, a hearing aid, a cochlear implant system, a component of an auditory prosthesis, a sound processor of an auditory prosthesis, an actuator of an auditory prosthesis, a magnetic coupler of an auditory prosthesis, a microphone of an auditory prosthesis, a battery, and a rechargeable battery. 
     Embodiment 13: The apparatus of Embodiment 11 or Embodiment 12, wherein the dielectric region comprises a cavity substantially circumscribed by the electrically conductive layer and comprising an opening at a surface of the electrically conductive layer, the at least one capacitor extending across the opening. 
     Embodiment 14: The apparatus of any of Embodiments 11 to 13, wherein the resonance frequency is in a range between 2 GHz and 6 GHz. 
     Embodiment 15: The apparatus of any of Embodiments 11 to 14, further comprising a controller spaced from the circuit, the controller configured to wirelessly transmit electromagnetic signals to the circuit, to receive wirelessly transmitted electromagnetic signals from the circuit, or both. 
     Embodiment 16: A method comprising: wirelessly receiving a first plurality of electromagnetic signals at an electrically conductive structure of an electronic device, the electrically conductive structure circumscribing a non-electrically-conductive material, the electrically conductive structure having a resonance frequency, the electrically conductive structure comprising a portion of a housing of the electronic device or a portion of an electrically-conductive layer of the electronic device; resonantly coupling the first plurality of electromagnetic signals with the electrically conductive structure; generating a first plurality of electrical signals in response to the first plurality of electromagnetic signals; and operating the electronic device in response to the first plurality of electrical signals. 
     Embodiment 17: The method of Embodiment 16, further comprising: generating a second plurality of electrical signals; and using the electrically conductive structure to generate a second plurality of electromagnetic signals in response to the second plurality of electrical signals. 
     Embodiment 18: The method of Embodiment 17, further comprising: transmitting the first plurality of electromagnetic signals from a controller of the electronic device to the electrically conductive structure, wherein the controller is spaced from the electronic device; and transmitting the second plurality of electromagnetic signals from the electrically conductive structure to the controller. 
     Embodiment 19: The method of Embodiment 18, further comprising receiving the second plurality of electromagnetic signals at the controller. 
     Embodiment 20: The method of any of Embodiments 16 to 19, wherein the electrically conductive structure comprises a circuit comprising an inductor and at least one capacitor in electrical communication with the inductor.