Abstract:
The present subject matter includes a hearing aid housing, a microphone, a wireless communication circuit, hearing aid electronics disposed in the housing, the hearing aid electronics connected to the wireless communication circuit and the microphone, an insertion removal handle connected to the hearing aid housing, the insertion removal handle extending away from the hearing aid housing and an antenna disposed within the insertion removal handle, the antenna connected to the wireless communication circuit, wherein at least a portion of the antenna disposed within the insertion removal handle is coiled.

Description:
RELATED APPLICATION 
   This application is a continuation under 37 C.F.R. 1.53(b) of U.S. application Ser. No. 10/768,735 filed Jan. 30, 2004 now U.S. Pat. No. 7,256,747, which is incorporated herewith and made a part hereof. 

   TECHNICAL FIELD 
   This application relates generally to hearing aids using antenna for wireless communication, and more particularly, to hearing aids including antenna proximal to a handle. 
   BACKGROUND 
   One goal of hearing aids is to replicate natural hearing. To achieve this goal, hearing aids must satisfy multiple requirements. One requirement is that hearing aids be comfortable and discreet. Another requirement is that they improve hearing. Any external addition to a hearing aid can be aesthetically undesirable, physically restrictive, uncomfortable, or result in other unwanted characteristics. Any internal additions to hearing aids can reduce the amount of space available to other components, such as computers, used to improve hearing. 
   In order to improve hearing, some hearing aids communicate and react with other devices. However, communication can require an antenna, which may increase size of the hearing aid. An antenna which protrudes from outside the hearing aid can be aesthetically unappealing and can receive increased electromagnetic interference. 
   Thus, there is a need for a wireless hearing aid having a space-efficient antenna configuration which provides adequate communications, does not reduce aesthetic appeal, comfort, or other performance requirements, and does not increase electromagnetic interference. 
   SUMMARY 
   The above-mentioned problems and others not expressly discussed herein are addressed by the present subject matter and will be understood by reading and studying this specification. 
   Completely-in-the-canal hearing aids, in-the-canal hearing aids, and in-the-ear hearing aids, in various embodiments, use a feature known as an insertion removal handle, removal cord, or pull cord. The hearing aid user can use the handle to assist in removing or inserting the device. In some embodiments, the handle is used to both remove and insert a hearing aid. The present subject matter includes an antenna designed in combination with a handle. 
   Some hearing aids communicate with other devices, such as programmers, using wireless connections. The present subject matter includes an antenna to communicate wirelessly. 
   The various embodiments described herein relate to a handle with an integrated antenna. One benefit of the present subject matter is that it reduces stress passed to the antenna. Additionally, the present subject matter satisfies various aesthetic requirements. A further benefit of the present subject matter is that the location of the antenna in relation to the location of other components within the hearing aid can result in reduced electromagnetic interference, which can allow for a reduction in electromagnetic shielding. The present subject matter includes other benefits and solutions in addition to those enumerated above. 
   One aspect of the present subject matter relates to a hearing aid having a housing with a faceplate to which a handle is connected. Additionally, an at least partially coiled antenna is located proximal to the faceplate, and electronics are connected to the antenna. 
   A further aspect relates to an apparatus comprised of a means for locating hearing aid components in a housing, and a means for manipulating a hearing aid with a handle. Further, the apparatus is comprised of a means for connecting the handle to the housing, and a means for integrating an antenna with the handle, wherein the antenna is located proximal to the housing, and is connected to electronics. 
   A further aspect relates to a method of making a hearing aid, including connecting an antenna to a handle, and connecting the handle to the hearing aid, wherein the antenna is located proximate to the hearing aid housing. 
   This Summary is an overview of some of the teachings of the present application and is not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details about the present subject matter are found in the detailed description and appended claims. Other aspects will be apparent to persons skilled in the art upon reading and understanding the following detailed description and viewing the drawings that form a part thereof, each of which are not to be taken in a limiting sense. The scope of the present invention is defined by the appended claims and their equivalents. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. 
       FIG. 1  illustrates one embodiment of a hearing aid which can employ an antenna according to one embodiment of the present subject matter. 
       FIG. 2A  illustrates one embodiment of a wireless rod antenna for use in hearing aids according to one embodiment of the present subject matter. 
       FIG. 2B  illustrates one embodiment of a wireless ring antenna for use in hearing aids according to one embodiment of the present subject matter. 
       FIG. 3A  illustrates an isometric cut-away view of one embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter. 
       FIG. 3B  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the conductor is located between the faceplate and an antenna flange. 
       FIG. 3C  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the antenna flange is located between the faceplate and the conductor. 
       FIG. 3D  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the conductor is recessed in the faceplate. 
       FIG. 4A  illustrates an isometric cut-away view of one embodiment of a rod shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter. 
       FIG. 4B  illustrates a side view of one embodiment of a rod shaped antenna, showing the faceplate and handle cut away, and showing the antenna connected to a handle for a hearing aid in accordance with the present subject matter. 
       FIG. 4C  illustrates a side view of one embodiment of a rod shaped antenna, showing the faceplate cut away, and showing the antenna connected to a handle for a hearing aid in accordance with the present subject matter. 
       FIG. 5  illustrates one embodiment of a ring shaped antenna integrated inside a handle according to one embodiment of the present subject matter. 
       FIG. 6  illustrates a method for constructing a hearing aid including a handle, with an antenna integrated with the handle according to one embodiment of the present subject matter. 
       FIG. 7A  illustrates one embodiment of a hearing aid which can facilitate rotary movement of the handle through commutation according to one embodiment of the present subject matter. 
       FIG. 7B  illustrates one embodiment of a hearing aid which can facilitate axial movement of the handle through flexible conductors connecting the antenna to other components, according to one embodiment of the present subject matter. 
       FIG. 7C  illustrates one embodiment of a hearing aid which can facilitate rotary movement of the handle through flexible conductors connecting the antenna to other components, according to one embodiment of the present subject matter. 
       FIG. 7D  illustrates one embodiment of a hearing aid which facilitates movement of the handle according to one embodiment of the present subject matter. 
       FIG. 8  shows one example of a transmission circuit for use with the antenna of the present system, according to one embodiment of the present subject matter. 
       FIG. 9  illustrates one example of a circuit capable of both transmission and reception for use with the antenna of the present subject, according to one embodiment of the present subject matter. 
   

   DETAILED DESCRIPTION 
   The following detailed description of the present invention refers to subject matter in the accompanying drawings which show, by way of illustration, specific aspects and embodiments in which the present subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present subject matter. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the present subject matter. References to “an”, “one”, or “various” embodiments in this disclosure are not necessarily to the same embodiment, and such references contemplate more than one embodiment. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope is defined only by the appended claims, along with the full scope of legal equivalents to which such claims are entitled. 
   Various aspects and embodiments of the present subject matter include components to a hearing aid. The present subject matter includes connecting a wireless antenna proximal to a handle of a hearing aid. The present subject matter also includes connecting the handle proximal to the hearing aid housing. Additionally, the present subject matter includes connecting the handle and the hearing aid housing such that the antenna is proximal to the hearing aid housing. 
   One benefit of the present subject matter is that it reduces electromagnetic interference by allowing the antenna to be mounted in an improved proximity to other components within the hearing aid. A further benefit of the present subject matter is that it is space-efficient. An additional benefit of the present subject matter is that the antenna does not protrude from the hearing aid in an unaesthetic fashion. The benefits offered by the present subject matter are not limited to those enumerated here. 
     FIG. 1  illustrates one embodiment of a hearing aid. In various embodiments, the hearing aid fits into the ear at least partially. Once inserted, hearing aids can be difficult to manipulate without a handle  102 . The handle  102  sticks out of the ear and allows the user to grasp it and manipulate the hearing aid. 
   In various embodiments, the handle  102  is fastened to the faceplate  101 . Faceplate  101  includes a microphone  104 . Various embodiments include a faceplate  101  formed of a stiff polymeric material. In various embodiments, the faceplate forms at least part of the exterior envelope of the hearing aid. In various embodiments, the faceplate  101  is a standard shape, and the shell  103  is molded to fit an individual ear canal. Various embodiments are contemplated by the present subject matter. For example, other embodiments include a shell  103  and faceplate  101  molded in concert to fit an individual ear canal. Other embodiments not enumerated herein are possible without departing from the scope of the present subject matter. 
     FIG. 2A  illustrates one embodiment of a wireless rod antenna for use in hearing aids according to one embodiment of the present subject matter. In various embodiments, the rod antenna comprises a solid ferrite core  201  around which conductor  202  is wrapped. However, the present subject matter is not limited to such component materials or geometries. One embodiment includes a hollow core. Further embodiments include a core composed of a non-ferrous material. These and other embodiments are within the scope of the present subject matter. 
   Various embodiments include a core  201  which ranges between approximately 2 millimeters and 6 millimeters long, and ranges between approximately 0.5 millimeters and 2 millimeters in diameter. One embodiment includes a solid ferrite core which is approximately 4 millimeters long and approximately 1 millimeters in diameter. However, the present subject matter is not limited to such component materials or geometries; various embodiments include a hollow core, and further embodiments are made from non-ferrous materials. 
   In various embodiments the core  201  is wrapped with conductor multiple times. Various embodiments include a configuration which is wrapped with conductor between approximately 40 and approximately 120 turns. One embodiment includes a core which is wrapped approximately 90 turns. Further embodiments include a core which is wrapped with separate conductors, allowing a separate number of wrappings for transmitting and receiving. 
     FIG. 2B  illustrates one embodiment of a wireless ring antenna for use in hearing aids according to one embodiment of the present subject matter. In various embodiments, the conductor  252  is wrapped around a ring shaped ferrite core  251 , such that the center axis formed by the loops of conductor is collinear with the center axis of the ring. However, the present subject matter is not limited to such component materials or geometries; in one embodiment, the core is solid, i.e., disk shaped, and in further embodiments, the core is made from non-ferrous materials. These and other embodiments are within the scope of the present subject matter. 
   Various embodiments include a ring shape comprised of various length-wise segments of different diameters. In one example, the shape includes a smaller diameter segment  251  around which the conductor is wrapped, and a larger diameter segment  253 , around which conductor is not wrapped. In various embodiments, the conductor wrapped segment ranges between approximately 1 millimeters and approximately 5 millimeters in length, and between approximately 2 millimeters and approximately 3 millimeters in diameter. In one embodiment, the conductor wrapped segment is approximately 2.5 millimeters long, and approximately 3 millimeters in diameter. 
   Various embodiments include a configuration which is wrapped with conductor between approximately 50 and approximately 70 times. In one embodiment, the core is wrapped approximately 60 times by conductor. Further embodiments include a core which is wrapped with separate conductors, allowing a separate number of wrappings for transmitting and receiving. 
   In various embodiments, the choice between a ring antenna embodiment and a rod antenna embodiment will depend on various performance characteristics. In various ring embodiments, the ring shape allows the handle to be placed through the center portion of the antenna. In various embodiments, this allows portions of the antenna to reside within recesses of the housing, while allowing the handle to function as part of an adjustment system. In various embodiments, positioning the antenna in a recess in the housing can increase space within the hearing aid. Increased space within the hearing aid can allow improvements in other components, such as computers or batteries. 
   Various embodiments of the rod antenna demonstrate increased robustness in the polar pattern of the antenna. An increased robustness in an antenna polar pattern can decrease the sensitivity between antenna orientation and antenna function, allowing for a greater range of functional antenna orientations. In various embodiments, improved robustness of the polar pattern is due to an improved aspect ratio. An improved aspect ratio can result in improved performance overall. Additionally, various embodiments of the rod antenna are less expensive to manufacture than ring embodiments. The scope of the present subject matter includes all of these benefits, but is not to be understood as limited to those benefits enumerated here. 
     FIG. 3A  illustrates an isometric cut-away view of one embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter. In various embodiments, the portion of the antenna wrapped with conductor  302  is located between the faceplate  305  and the antenna flange  303 . In further embodiments, the antenna is located between the handle flange  304  and the faceplate  305 . In addition to embodiments in which the handle  301  serves as a useful device for removing and inserting a hearing aid, in various embodiments, the handle is part of an adjustment system. In one embodiment, the handle  301  can be rotated to adjust volume. Further embodiments adjust frequency response, compression, and any other adjustable variable useful to control hearing aid function. These adjustments, in various embodiments, are achieved by interacting with other system components, e.g. a potentiometer. 
     FIG. 3B  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the conductor is located between the faceplate and an antenna flange. In various embodiments, the smaller diameter segment  302  is mounted proximal to the faceplate  305 , and the larger diameter segment  303  is located distal to the faceplate  305 . Additionally, in various embodiments, the larger diameter segment  303  is mounted proximal to a larger diameter segment  304  of the handle  301 . The larger diameter segment  304  of the handle  301 , in various embodiments, sandwiches the antenna between itself  304  and the faceplate  305 . 
     FIG. 3C  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the antenna flange  323  is located between the faceplate  325  and the conductor  322 . In one embodiment, the smaller diameter segment  322  is mounted distal to the faceplate  325 , and the larger diameter segment  323  is located proximal to the faceplate  325 . Additionally, in various embodiments, the smaller diameter segment  322  is mounted proximal to a larger diameter segment of the handle  324 . The larger diameter segment of the handle  324 , in various embodiments, sandwiches the antenna between itself  324  and the faceplate  325 . 
     FIG. 3D  illustrates a side cut-away view of an embodiment of a ring shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter, such that the conductor is recessed in the faceplate. In various embodiments, mounting all or portions of the antenna in a recess in the faceplate can increase the space available in the interior of the hearing aid. Increased space can be used for improvements in computers or other components. 
   In one embodiment the smaller diameter segment  337  is mounted in a recess in the faceplate  335 , and the larger diameter segment  333  is located further away from the exterior of the hearing aid  338 . In further embodiments, the smaller diameter segment  337  is located further from the exterior of the hearing aid  338  than the larger diameter segment  333 . 
   In various embodiments, the larger segment  333  may also be at least partially located within a recess, or the smaller portion  337  may be only partially located within the recess. Additionally, in various embodiments, the larger diameter segment  333  is mounted proximal to a larger diameter segment of the handle  334 . The larger diameter segment  333  of the handle  331 , in various embodiments, sandwiches the antenna between itself  334  and the faceplate  335 . 
   The present subject matter, however, is not to be understood as limited to these geometries or component orientations. One embodiment includes an orientation in which the larger diameter segment  333  is recessed in the faceplate  335 , and the smaller diameter segment  337  is located proximate to the larger diameter segment  334  of the handle. Further embodiments include a range of recess depths in which the antenna is located. 
   Further embodiments also mount the antenna at an angle, such that the center axis of the antenna is separated from the center axis of the handle by a range of degrees when measured at their intersection. In other embodiments, the axes are skewed or parallel. These and other embodiments are within the scope of the present subject matter, and the present subject matter is not to be understood as limited to the embodiments enumerated here. 
     FIG. 4A  illustrates an isometric cut-away view of one embodiment of a rod shaped antenna connected to a handle for a hearing aid in accordance with the present subject matter. The figure is cut away to show the detail of the solid core  403  and the conductor wrappings  402  mounted in a handle  401 . 
     FIG. 4B  illustrates a side view of one embodiment of a rod shaped antenna, showing the faceplate and handle cut away, and showing the antenna connected to a handle for a hearing aid in accordance with the present subject matter.  FIG. 4B  shows a cut away side view of a rod antenna mounted in the handle. Additionally,  FIG. 4B  illustrates a cut away view of the hearing aid faceplate. In various embodiments, the rod antenna includes a solid core  403 , around which conductor  402  is wrapped. In various embodiments, the rod antenna is longer than the cavity in the handle  401  into which it is received. In other embodiments, it is not. Various embodiments employ a variety of fits between the handle and the rod antenna, including interference, non-interference, or any combination thereof. In addition to the type of fit used, various embodiments can employ adhesive fastening, encapsulation, or various combinations of known fastening methods. 
   Additionally, the handle fits into a receiving channel in the faceplate  404 . Various embodiments employ a variety of fits between the handle and the faceplate  404 , including interference, non-interference, or any combination thereof. In addition to the type of fit used, various embodiments can employ adhesive fastening, or various combinations of known fastening methods. 
     FIG. 4C  illustrates an side view of one embodiment of a rod shaped antenna, showing the faceplate cut away, and showing the antenna connected to a handle for a hearing aid in accordance with the present subject matter. In various embodiments, the rod antenna includes a solid core  403 , around which conductor  402  is wrapped. This figure illustrates how the rod antenna can partially stick out from the receptacle in the handle  401 . The figure further illustrates one embodiment of the handle connection to the faceplate  404 . 
     FIG. 5  illustrates one embodiment in which a ring shaped antenna is located inside a handle. In various embodiments, the ring antenna includes a core  503 , around which conductor  502  is wrapped. In various embodiments, the ring antenna is longer than the cavity in the handle  501  into which it is received. In other embodiments, it is not. Various embodiments employ a variety of fits between the handle  501  and the ring antenna, including interference or non-interference, or any combination thereof In addition to the type of fit used, various embodiments can employ adhesive fastening, encapsulation, or various combinations of known fastening methods. 
     FIG. 5  additionally illustrates that the handle fits into a receiving channel in the faceplate. Various embodiments employ a variety of fits between the handle  501  and the faceplate  505 , including interference or non-interference, or any combination thereof. In addition to the type of fit used, various embodiments can employ adhesive fastening, or various combinations of known fastening methods. 
     FIG. 6  illustrates a method for constructing a handle with an antenna integrated with the handle. In various embodiments, the method connects  602  the handle to the hearing aid faceplate. In further embodiments, the method coils  601  a conductor around a ferrite core. The method, in various embodiments, also includes connecting  603  the antenna to the handle. The method, in additional embodiments, connects the handle to the hearing aid housing. In further embodiments, the antenna is located proximal to the faceplate. 
     FIG. 7A  illustrates one embodiment of a hearing aid which can facilitate rotary movement of the handle through commutation according to one embodiment of the present subject matter. In various embodiments, the antenna  701  experiences rotation as the handle is rotated to adjust a hearing aid parameter, such as signal gain. Various embodiments include brushes  703  which contact a commutator  702 , allowing the commutator  702  to rotate independent of the brushes  703 , while maintaining an ability to conduct electricity to components  704 . In various embodiments, the result is an apparatus which can conduct electricity between the antenna  701  and the hearing aid components  704  while allowing the antenna  701  to rotate freely and without limit. One benefit of this embodiment is that it allows the antenna to rotate freely without putting excess physical stress on the conductors  705 . 
     FIG. 7B  illustrates one embodiment of a hearing aid which can facilitate axial movement of the handle through flexible conductors connecting the antenna to other components, according to one embodiment of the present subject matter. In various embodiments, the conductor can include additional length  725 , so that the antenna can move independent of other components to which the conductors are attached, without damaging the conductors. Various embodiments allow depression of the handle to allow selection of one or more hearing aid parameters, such as signal gain. In various embodiments, the axial movement of the handle is mechanically limited so that the user may not move the antenna beyond the range of motion permitted by the additional length  725 . In various embodiments, the faceplate  724  constrains the handle  721  during axial movement. 
     FIG. 7C  illustrates one embodiment of a hearing aid which can facilitate rotary movement of the handle through flexible conductors connecting the antenna to other components, according to one embodiment of the present subject matter. In various embodiments, the conductor can include additional length  742 , so that the antenna can move independent of the other component to which the conductors are attached, without damaging the conductors. In various embodiments, the full rotation of the handle  741  is mechanically limited so that the user may not rotate the antenna  744  beyond the range of motion permitted by the additional length  742 . In various embodiments, the faceplate  743  constrains the handle  741  during rotation, in others, it does not. 
     FIG. 7D  illustrates one embodiment of a hearing aid which facilitates movement of the handle according to one embodiment of the present subject matter. In various embodiments, a bearing  736  is fixed to the faceplate  735 , and the antenna is fixed to the faceplate  735 . In additional embodiments, the antenna is fixed to the faceplate  735 , and the bearing  736  is fixed to the antenna. In some embodiments, the bearing may extend completely through the thickness of faceplate  735 , and in others, it extends part of the way through. In further embodiments, the bearing may extend completely through the antenna, and in other embodiments, it extends part of the way through. In various embodiments, components which are fixed are mechanically joined using an interference fit. In other embodiments, they are joined using adhesives, or other joining methods. It should be noted that the scope of the present subject matter includes various bearings, plastic bushings, and other apparatus which facilitate movement of the handle  731 . Additionally, the present subject matter includes embodiments which do not include a bearing, but include a friction reducing coating applied either to the handle  731 , the passageway through which the handle  731  passes, or both. 
   Various embodiments allow limitless rotation of the handle  731 , and other embodiments limit rotation. Further embodiments include axial movement, and still further embodiments involve axial movement exclusively. In various embodiments, the axial movement of the handle is limited mechanically. 
   In various embodiments, at least a portion of the antenna is located in a recess in the faceplate  735 . Other embodiments do not include a recess. Additionally, in various embodiments, the ring shaped antenna may be configured so that either the larger diameter section  733  or the smaller diameter section  737  are nearest to the exterior of the hearing aid  738 . 
     FIG. 8  shows one example of a transmission circuit  800  for use in combination with embodiments of the antenna  802  of the present system. In the example of  FIG. 8 , input signal, I is provided to the circuit and an oppositely phased signal, I′, is produced by the inverter  804 . It is noted that in this particular example, the information transmitted is digital and the switching electronics employ digital gates for inversion and switching in general. Other embodiments may employ nonstandard switching electronics with bipolar voltage supplies and other variations without departing from the scope of the present invention. In the example provided in  FIG. 8 , the modulation is amplitude shift keying. However, it is understood that other modulation techniques may be employed without departing from the scope of the present application. Such modulation techniques include, but are not limited to, phase shift keying, frequency shift keying, pulse amplitude modulation, frequency modulation, and amplitude modulation. 
   The I signal is provided to the gates of field effect transistors M 1  and M 2  and the I′ signal is provided to the gates of field effect transistors M 3  and M 4 , which are connected as shown in  FIG. 8  In this example, the transistors drive antenna  802 , which may be modeled as having an intrinsic resistance, R1 (not shown) and inductance, L1 (not shown), in series with capacitor C 1 . In one embodiment, the resulting circuit is a D-class amplifier in an H-bridge configuration to drive L1 and C 1 . Resistor Rx is used to set the Q of the circuit. 
   In operation, when the input signal, I, is a logic high, then transistor M 1  is not conducting and transistor M 2  is conducting, which forces the output voltage at output  806  a logic low. I′ is a logic low when I is logic high. Consequently, when I′ is a logic low, then M 3  is not conducting and M 4  is conducting, which forces the output voltage at output  808  to a logic high. 
   It is noted that field effect transistors also provide a form of overvoltage protection, since they serve as diodes in the reverse-conduction direction which clamp the output signals  806  and  808  between the applied voltage rails (in this example, Vdd and ground). 
   It is noted that the polarities of the supplies, use of logic low and logic high states, and voltage levels may be changed without departing from the scope of the present subject matter. Also, other types of transistors and configurations may be employed without departing from the scope of the present application. In one embodiment, bipolar junction transistors are used to provide switching. Other switching structures may be utilized without departing from the scope of the present teachings. 
   In such embodiments, it is possible to use, for instance, a communications signal having approximately an 80 meter wavelength to communicate with a wire antenna  802  that may have a length of approximately 1 meter. Such communications may be conducted with primarily inductive coupling (primarily the H field) at low power levels. In one embodiment, a level of less than 1 milliwatt may suffice for short range communications with the antenna  802 . In such embodiments, a distance of 20 to 50 centimeters may be used for communications between the transmitter and receiver. Other wavelengths and power levels may be employed and other distances may be used without departing from the scope of the present subject matter. 
   One advantage of the short range nature of the communications is that other electronics will operate without radio frequency interference and other hearing devices may be programmed in proximity and even at the same time without interference. 
   In another embodiment, a system is shown where a receiver and transmitter are connected to an antenna  902  for transmission and reception.  FIG. 9  shows a transmitting and receiving circuit  900  with a receiving amplifier  904  and additional circuitry  910  for controlling the communications for both transmission and reception. 
   In the example of  FIG. 9 , a transmit mode and a receive mode are switched by changing the TX/RX′ input. In this example embodiment, transmit mode is identified by a logic high signal into the TX/RX′ input. With TX/RX′ at a logic high value, the switching circuit  910  includes a switch  912  which routes the input signal, IN, to the input of the transmitting circuit  900 , I. The logic high value of the TX/RX′ signal also causes NAND gate  914  to act as an inverter of the I signal. This permits transmitter circuit  900  to operate much like transmitter  800  in  FIG. 8  during transmission mode. The input of low noise amplifier  904 , which is denoted as node  916 , is at a logic low value, since transistor M 5  is conducting when its gate is at a logic high for transmit mode. Thus, the low noise amplifier  904  is not receiving signals from antenna  902  during transmission. 
   In transmission mode, the I signal is provided to the gates of field effect transistors MI and M 2  and the I′ signal is provided to the gates of field effect transistors M 3  and M 4 , which are connected as shown. NAND gate  914  inverts the I signal while TX/RX′ is logic high (in the transmit mode). In this example, the transistors M 1 , M 2 , M 3 , and M 4  drive antenna  902 , which may be modeled as having an intrinsic resistance, R 1  (not shown) and inductance, L 1  (not shown), in series with capacitor C 1 . In one embodiment, the resulting circuit is a D-class amplifier in an H-bridge configuration to drive L 1  and C 1 . Resistor Rx is used to set the Q of the circuit. 
   In operation, when the input signal, I, is a logic high, then transistor M 1  is not conducting and transistor M 2  is conducting, which forces the output voltage at output  906  a logic low. I′ is a logic low when I is logic high. Consequently, when I′ is a logic low, then M 3  is not conducting and M 4  is conducting, which forces the output voltage at output  908  to a logic high. 
   It is noted that field effect transistors also provide a form of overvoltage protection, since they serve as diodes in the reverse-conduction direction which clamp the output signals  906  and  908  between the applied voltage rails (in this example, Vdd and ground). 
   It is noted that the polarities of the supplies, use of logic low and logic high states, and voltage levels may be changed without departing from the scope of the present subject matter. Also, other types of transistors and configurations may be employed without departing from the scope of the present application. In one embodiment, bipolar junction transistors are used to provide switching. Other switching structures may be utilized without departing from the scope of the present teachings. 
   When the TX/RX′ line is logic low, the device is in receive mode. In receive mode, the output of the NAND gate will always be at a logic high, since the TX/RX′ line is at a logic low. The switching circuit  910  includes a switch  912  which switches I to Vdd (logic high) during receive mode. This places outputs  906  and  908  at logic low levels and provides reception by amplifier  904  via capacitor C 2 , as the TX/RX′ signal is logic low and M 5  is nonconducting. In this embodiment, the antenna  902  and capacitor C 1  form a parallel resonant tank receiver circuit for small signals received by antenna  902 . 
   Other variations are possible which provide receive mode and transmit mode using the antenna  902  and without departing from the teachings of the present subject matter. 
   Upon reading and understanding the present subject matter, one skilled in the art will appreciate that various hardware, connections, and combinations of components may be employed to accomplish the present subject matter. For instance, the transmission and reception modes may be performed using different hardware and different logic level signals. For example, the switching circuit  910 , in various embodiments, may use an embedded microprocessor, microcontroller and may be embodied in various combinations of hardware and software. 
   One of ordinary skill in the art will understand that, the systems shown and described herein can be implemented using software, hardware, and combinations of software and hardware. As such, the term “system” is intended to encompass software implementations, hardware implementations, and software and hardware implementations. 
   Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement which is calculated to achieve the same purpose can be substituted for the specific embodiment shown. This application is intended to cover adaptations or variations of the present subject matter. It is to be understood that the above description is intended to be illustrative, and not restrictive. Combinations of the above embodiments, and other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the present subject matter should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.