Patent Publication Number: US-2013234906-A1

Title: Sleeve Dipole Antenna Microphone Boom

Description:
BACKGROUND OF THE INVENTION 
     Wireless headsets require an antenna to permit a headset transceiver to communicate with a corresponding base transceiver. Antennas used in wireless headsets utilize space that must be considered in the design of the headset. The headset antennas must be small because the headsets themselves are small. For example, the size of headset bodies may be on the order of 30 mm in length or less. However, at the same time, the antennas must still be operable in the desired frequency band: 
     In the prior art, headset antennas have been constructed using planar inverted-F antennas (PIFAs), resonators, or other designs, on the headset circuit boards. These prior art designs rely on the circuit board to act as a counterpoise and the size of circuit board usually determines performance. For example, PIFA antennas require large ground planes, thereby making it difficult to provide a small device with good antenna characteristics. As the size of headsets decreases, the size of the circuit board and attached antenna necessarily decreases, resulting in performance degradations related to the transmission characteristics and gain of the antenna. 
     Furthermore, there is a substantial loss of efficiency of these antennas when used near a human head as the human body affects the electromagnetic field radiation pattern of the antenna. In the prior art designs, the headset circuit board is often close to the user head, further degrading performance. 
     As a result, improved methods and apparatuses for headset antennas are needed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements. 
         FIG. 1  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in one example. 
         FIG. 2  illustrates a simplified disassembled view of select components of the sleeve dipole antenna boom assembly shown in  FIG. 1  in one example implementation. 
         FIG. 3  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom, assembly in a further example. 
         FIG. 4  illustrates a simplified disassembled view of select components of the sleeve dipole antenna boom assembly shown in  FIG. 3  in one example implementation. 
         FIG. 5  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in which conductive elements are disposed on a plastic housing. 
         FIG. 6  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in which conductive elements are disposed on a plastic housing in a further example. 
         FIG. 7  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in which conductive elements are disposed within a plastic housing. 
         FIG. 8  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in which, conductive elements are disposed within a plastic housing in a further example. 
         FIG. 9A  illustrates a front view of a headset with a boom having a sleeve dipole antenna. 
         FIG. 9B  illustrates a rear view of the headset shown in  FIG. 9A . 
         FIG. 10  illustrates a perspective view of a sleeve dipole antenna boom assembly in a further example. 
         FIG. 11  illustrates a simplified perspective view of a sleeve dipole antenna boom assembly in one example. 
         FIG. 12  illustrates the sleeve dipole antenna boom assembly shown in  FIG. 11  with an antenna upper arm removed to illustrate an antenna feed and wire assembly shield attachment 
     
    
    
     DESCRIPTION OF SPECIFIC EMBODIMENTS 
     Methods and apparatuses for headset antennas are disclosed. The following description is presented to enable any person skilled in the art to make and use the invention. Descriptions of specific embodiments and applications are provided only as examples and various modifications will be readily apparent to those skilled in the art. 
     The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed herein. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention. 
     Antenna solutions in head worn devices are presented herein. A half-wave dipole antenna is relatively broadband in wireless communication bands and therefore requires little production tuning for narrowband applications like wireless headsets. The half-wave dipole antenna advantageously does not easily detune. A sleeve antenna is one design of a half-wave dipole antenna. The sleeve antenna consists of a dipole, where the feed is brought through one arm of the dipole. Because the feed is within the antenna conductors, it is shielded from the radiating currents. This aids proper performance of the antenna. 
     However, the half wave dipole antenna requires a quarter wavelength for each arm (on the order of 30 mm for the Bluetooth band at 2.45 GHz in free space). This length can be reduced by putting plastic near the radiators, but the more this techniques is used, the less efficient the antenna. Unfortunately, the size of the main capsule of many Bluetooth headsets today is much less than 60 mm (both anus of dipole), thereby effectively preventing the use of a half wave dipole antenna. But many headsets have a microphone boom (for example, an elongated structure) attached to enhance microphone performance by placing an acoustic wave sensing point closer to a user mouth. The closer the boom tip is to the mouth, generally the better performance. The distance from ear to mouth is on the order of 80 mm or more. In one example of the invention, a Bluetooth band half-wave sleeve dipole is advantageously accommodated in the boom. Advantageously, antenna performance is improved as the antenna is held further away from the head than in designs with the entire antenna entirely in the capsule, reducing the amount of power absorption and detuning resulting from the user head. Furthermore, the antenna is a half-wave dipole with one arm acting as a counterpoise, rather than a quarter-wave monopole with the ground (counterpoise) provided by the PCB in the headset capsule. This also reduces the power absorption and detuning due to the user head in these designs. Finally, the arms of the sleeve dipole acts as a balun, reducing the currents induced on the feed and conducted into the PCB, providing isolation, pattern improvement, better efficiency and less detuning. In one example, the internal microphone assembly may extend beyond the end of the tube connected to the inner conductor of the coax, with the same balun effect. In this case, the microphone must have a conductive coaxial shield around them and extend beyond the end of the tube as well. This shield must form a transmission line with the antenna tube connected to the inner connector of the coax. 
     The microphone boom can be constructed with the microphone at the tip, connected by conducting wires to the headset or be constructed with an air tube that conducts the sound to a microphone embedded in the headset. In a further example, the microphone may be located anywhere within the boom. There can be small openings and slots in the metal tubes (and plastic) that allow for multiple microphones. The small openings do not disturb the radiation significantly as long as they are less than λ/10 where λ is the desired radiation wavelength of the antenna. For comfort, the booms are often away from the face rather riding directly on it. 
     In one example the function of the boom of the headset used for audio is combined with a half-wave sleeve dipole used for RF. A variety of configurations may be implemented depending upon whether the boom is air tube or microphone wired and whether the boom is extensible or fixed. 
     In one example, a boom assembly includes an integrated sleeve dipole antenna. A first boom component is configured as a sleeve radiating element and a second boom component is configured as a radiating element. 
     In one example, a boom assembly includes a RF feeding coaxial cable having an outer conductor and a central conductor. The boom assembly includes a first boom component, the first boom component coupled to the central conductor and configured as an antenna radiating clement. The boom assembly includes a second boom component electrically isolated from the first boom component, where the second boom component has a portion of the RF feeding coaxial cable disposed within and the second boom component is coupled to the outer conductor and configured as an antenna sleeve radiating element. 
     In one example, a headset includes a body configured to be worn on a user ear and a boom coupled to the body. The boom coupled to the body includes a radiating element, and a sleeve radiating element arranged to be electrically isolated from the radiating element. A RF feeding coaxial cable is disposed within the sleeve radiating element. The RF feeding coaxial cable includes an outer conductor and a central conductor, where the outer conductor is coupled to the sleeve radiating element. 
     In one example implementation for a fixed boom with microphone wires, the boom consists of two metal tubes electrically insulated from each other and insulated from the main headset housing. The microphone wires are passed from the headset base to the boom end through the tubes. In one example, the microphone wires are advantageously in a coaxial structure or shield tube with the external conductor/tube grounded to the same potential as the antenna feed shield as shown in  FIG. 11  and  FIG. 12 .  FIG. 11  illustrates a simplified perspective view of a sleeve dipole antenna boom assembly in one example.  FIG. 12  illustrates the sleeve dipole antenna boom assembly shown in  FIG. 11  with an antenna upper arm removed to illustrate an antenna feed and wire assembly shield attachment. As shown in  FIG. 11 , a sleeve dipole antenna boom assembly  1100  includes a wire assembly  1102  in a wire assembly shield  1104 , an antenna feed  1106  in an antenna feed shield  1108 , an antenna lower arm  1110 , and antenna upper arm  1112 . Referring to  FIG. 12 , the antenna feed  1106  consists of a coaxial wire brought to the insulating section. The shield  1108  of the feed coaxial cable connects to antenna lower arm  1110  (e.g., a metal tube) utilizing antenna feed shield and wire assembly shield attachment  1202 , and the center conductor of the antenna feed  1106  coaxial cable connects to antenna upper arm  1112  (not shown for clarity) utilizing antenna feed and wire assembly shield attachment  1204 . Microphone wire assembly shield  1104  connects to antenna lower arm  1108  via antenna feed shield and wire assembly shield attachment  1202  and connects to antenna upper arm  1112  via antenna feed and wire assembly shield attachment  1204 . 
     While in certain examples the microphone wires are outside the antenna metal tubes, generally, antenna performance will be better with them within the tubes and in the preferred embodiment, advantageously within their own shield tube at the same potential as the antenna feed shield. If necessary, the feed shield and wire assembly shield can be electrically tied periodically along their edges to maintain equal potential The lower antenna tube forms a high-impedance with the coax feed and optional wire assembly shield, reducing induced currents that might change the antenna pattern or resonant frequency. The isolation of the metal tubes from the headset makes the antenna performance relatively unaffected from the headset conductor (PCB, case) size. 
     Further construction possibilities include having the center conductor of the feed coaxial cable exiting the first tube fanning out and becoming a cone that terminates all around the edge of the next tube, and the outer conductor fanning out and back and terminating all around the first tube. Any other conductors, like the boom microphone lead is fed through an aperture in these two structures. 
     In various examples, the two metal tubular sections can be made of extruded metal tubing, stamped metal folded/or bent on itself, or deposited metal coating on plastic. In addition, the metal can be covered in plastic or some other insulator. The dielectric constant of the insulator affects the length of the metallic sections. 
     For a fixed, boom with an, air tube, one example is to embed the air tube into the metal tubes used for the microphone wired solutions. However, it is undesirable for the coaxial cable to be inside the air tube for acoustic reasons (changes air tube acoustic properties, and requires a puncture of tube to pass coaxial cable wires). In further examples, a better solution is to have the coaxial cable sit side-by side with the air tube. This can be a custom molded part consisting of tube and coaxial cable. In this configuration, one could also have the air tube external to the metal tubes, with no degradation of performance. Finally, one can use the center conductor of the coaxial cable to replace one of the metal tubes. 
     For the extensible boom (e.g., a telescoping boom), it is required that the metal tubes slip between each other, but maintain their electrical isolation, and moving the wires/coaxial cable so they do not bind. The two metal tubes have differing diameters so that one can slide into the other. 
     Advantageously, because the boom is usually away from the face, there is less absorption and detuning of the antenna when it is collocated with the boom. Advantageously, the antennas dependence on the headset properties for performance is reduced. The antennas described herein may serve as a platform that can be used with many headset designs. Furthermore, the designs described herein free up real-estate that is usually required on the headset for the antenna. 
     In a further example, the solid coaxial nature of the antenna arms is not required. It is acceptable to have slits along the antenna if they are connected at the antenna feed as in the coaxial case and they remain equipotential to each other. One or more slits may be used as desired. If necessary, they can be electrically tied periodically along their edges to maintain equal potential. In particular, one embodiment consists of four substantially planar (curved or flat) plates where each arm of the antenna consists of two plates. 
     In one planar embodiment utilizing an air tube microphone, the antenna feed is coaxial. The outer conductor is soldered to a lower planar part and the center conductor is soldered to an upper planar part. 
     In a second planar embodiment utilizing microphone or other leads (i.e., auxiliary wires), the auxiliary wires are attached to the boom sleeve dipole. In one example, there is only one auxiliary wire which is the center conductor of the coaxial wire assembly, but there can be more than one wire internal to the coaxial wire assembly. In one example they are coaxial, but this is not a requirement. However, it is required that the auxiliary transmission line ground/shield is attached sufficiently well to the antenna feed shield (e.g., lower arm) that it is essentially equipotential with it and forms a transmission line with the antenna lower arm. When the auxiliary wires bridges the gap, the wires leave the ground/shield of the transmission line that is equipotential with the antenna feed and move to form another transmission line whose outer shield is terminated near where the antenna feed terminates on the upper arm and forms a transmission line with the antenna upper arm. When the wires jump the antenna arm gap, the shield must therefore be discontinuous. 
       FIG. 1  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in one example. In this example, a boom assembly  2  includes a RF feeding coaxial cable  8  having an outer conductor  12  and a central conductor  10 . The boom assembly  2  includes a first boom component  4 , the first boom component  4  coupled to the central conductor  10  and configured as an antenna radiating element. The boom assembly  2  includes a second boom component  6  electrically isolated from the first boom component  4 , where the second boom component  6  has a portion of the RF feeding coaxial cable  8  disposed within and the second boom component  6  is coupled to the outer conductor  12  and configured as an antenna sleeve radiating element. In one example, the first boom component  4  has an electrical length of approximately one-quarter wavelength of the frequency of interest (e.g., center frequency of the desired frequency band) and the second boom component  6  has an electrical length of approximately one-quarter wavelength of the frequency of interest. 
     The boom assembly  2  further includes a microphone  14  disposed at a far end of the first boom component  4 , and electrical leads  16  coupled to the microphone, the electrical leads  16  disposed within the first boom component  4  and the second boom component  6 . Generally, microphone  14  will utilize two leads  16 , but in further examples more leads may be used. Leads  16  are shown in  FIG. 1  as a single unit (e.g. line) for clarity. Similarly, the microphone leads in additional figures discussed below may also be shown as a single unit for clarity. Furthermore, there may be multiple microphones distributed inside the boom with small apertures in the tubes and plastic housing. In one example, the microphone leads  16  as well as any other wires extending through the boom (e.g., wires for buttons, LEDs, etc.) are advantageously in a coaxial structure or shield tube with the external conductor/tube grounded to the same potential as the antenna feed. 
     Although leads  16  and microphone  14  are illustrated in  FIG. 1  within the antenna, in one example, the leads  16  as well as any other wires and microphone  14  are extended beyond the antenna if they have a coaxial conductive shield that is connected near the same location as the coaxial inner conductor of the antenna feed, and forms a transmission line as it exits the upper arm. 
     In one example for 2.4 GHz operation, the length with no plastics on the outside of the first boom component  4  is between approximately 24-30 millimeters and the length of the second boom component  6  is between approximately 24-30 millimeters. The length will depend on the materials used, including whether there is a plastic coating on the metal tube and in general will be shorter when used with a plastic coating. In one example, the first boom component  4  is sized to fit within the second boom component  6  and arranged to extend or retract telescopically with respect to the second boom component  6 . 
       FIG. 2  illustrates a simplified disassembled view of select components of the sleeve dipole antenna boom assembly  2  shown in  FIG. 1  in one example implementation. In one example, the first boom component  4  comprises a first plastic member having a first conductive coating and the second boom component  6  comprises a second plastic member having a second conductive coating. For example, the first conductive coating or second conductive coating is a metal deposited on a surface of the first plastic member or a copper foil on a surface of the first plastic member. 
     In one example, the first boom component  4  is a metal tube and the second boom component  6  is a metal tube. In a further example, the metal tubes are coated with a plastic material or embedded within a plastic material. In one example, an insulating sleeve is disposed between the first boom component and the second boom component. 
     In operation, boom component  4  operates as a radiating element having an electrical length of approximately one quarter wavelength and boom component  6  operates as a sleeve (e.g., a cylindrical tube) radiating element having an electrical length of approximately one quarter wavelength. The central conductor  10  of coaxial cable  8  is connected to the radiating element (i.e., boom component  4 ), and the outer conductor  12  of coaxial cable  8  is connected to the sleeve radiating element (i.e., boom component  6 ). Coaxial cable  8  transmits radio frequency energy from a headset transceiver to the radiating element and sleeve radiating element. The point of transition from the coaxial cable  8  to the radiating element and sleeve radiating element is the antenna feed point and generally located at the junction of the radiating element and sleeve radiating element. 
     In one example, boom component  6  is a sleeve radiating element consisting of a tubular conductor with an antenna coaxial cable  8  coaxially aligned in the sleeve. The center conductor  10  of coaxial cable  8  extends beyond the point at which the outer conductor  12  is connected to the sleeve tubular conductor. The sleeve tubular conductor makes up the lower half of the antenna radiator and the length dimension is determined from the required length to cause the sleeve to be electrically resonant at the desired frequency. 
     Boom component  4 , boom component  6 , and coaxial cable  8  together are operable as a half wave sleeve dipole antenna laving good efficiency, directivity, and stable impedance. Advantageously, the microphone boom and the half wave sleeve dipole antenna utilize the same structural elements. 
       FIG. 3  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly  20  in a further example.  FIG. 4  illustrates a simplified disassembled view of select components of the sleeve dipole antenna boom assembly shown in  FIG. 3  in one example implementation. Boom assembly  20  is similar to boom assembly  2  shown in  FIG. 1  with the exception that microphone  14  and leads  16  have been replaced with a voice tube  22 . In the example shown in  FIGS. 3 and 4 , the voice tube  22  is utilized to receive acoustic sound waves corresponding to user speech at the distal end of the boom and transmit the acoustic waves the length of the boom assembly  20 . The acoustic waves are then detected by microphone disposed at a headset body or the near end of the boom assembly  20 . 
       FIG. 5  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly  500  in which conductive elements are disposed on a plastic housing  24 . A boom assembly  500  includes a RF feeding coaxial cable  32  having an outer conductor  36  and a central conductor  34 . The boom assembly  500  includes a first boom component  30 , the first boom component  30  coupled to the central conductor  34  and configured as an antenna radiating element. 
     The boom assembly  500  includes a second boom component  28  electrically isolated from the first boom component  30 , where the second boom component  28  has a portion of the RF feeding coaxial cable  32  disposed within and the second boom component  28  is coupled to the outer conductor  36  and configured as an antenna sleeve radiating element. In one example, the first boom component  30  has an electrical length of a one-quarter wavelength and the second boom component  28  has an electrical length of a one-quarter wavelength. 
     The boom assembly  500  further includes a microphone  40  disposed at a far end of the first boom component  30  (i.e., the distal end away from the headset body), and electrical leads  42  coupled to the microphone, the electrical leads  42  disposed within the first boom component  30  and the second boom component  28 . The plastic housing  24  includes an aperture  26  at the distal end for transmission of acoustic waves to the microphone  40 . A plastic housing  24  also includes an aperture  27 . Utilizing aperture  27 , the outer conductor  36  of cable  32  is connected to the conductive material of boom component  28  utilizing an electrical connection  38 . Similarly, utilizing aperture  27 , the central conductor  34  is coupled to the conductive material boom component  30 . In this manner, the two RF connections from the coaxial cable come through the same aperture in the housing and connect to adjacent opposite pieces (the ground shield to the tube containing the coaxial cable) for proper phasing of the antenna. 
     In one example, the first boom component  30  is a formed of a conductive coating disposed on a plastic housing  24  and the second boom component  28  is a conductive coating disposed on the plastic housing  24 . As shown in this example, the two conductive coatings are disposed on different sections of the plastic housing  24 . Thus, the first boom component and the second boom component may be different sections of a single piece boom. 
       FIG. 6  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly  600  in which conductive elements are disposed on a plastic housing in a further example. Boom assembly  600  is substantially similar to boom assembly  500  described above in reference to  FIG. 5  except as follows. Instead of utilizing microphone  40 , boom assembly  600  utilizes a voice tube  43  disposed within the boom component  30  and boom component  28 . The voice tube  43  includes an opening porting to aperture  26  of plastic housing  24 . The voice tube  43  receives a user voice sound wave at the distal end and transmits the sound wave to a microphone disposed at a headset housing coupled to the boom assembly  600  at a near end of the boom assembly  600 . 
       FIG. 7  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly in which conductive elements are disposed within a plastic housing  64 . A boom assembly  700  includes a RE feeding coaxial cable  54  having an outer conductor  58  and a central conductor  56 . The boom assembly  700  includes a first boom component  50 , the first boom component  50  coupled to the central conductor  56  and configured as an antenna radiating element. The boom assembly  700  includes a second boom component  52  electrically isolated from the first boom component  50 , where the second boom component  52  has a portion of the RF feeding coaxial cable  54  disposed within and the second boom component  52  is coupled to the outer conductor  58  and configured as an antenna sleeve radiating element. The first boom component  50  has an electrical length of approximately one-quarter wavelength and the second boom component  52  has an electrical length of approximately one-quarter wavelength. 
     The boom assembly  700  further includes a microphone  62  disposed at a distal end of the first boom component  50 , and an electrical lead  63  coupled to the microphone, the electrical leads  63  disposed within the first boom component  50  and the second boom component  52  and running from the microphone  62  to a near end of boom assembly  700 . 
     The plastic housing  64  includes an aperture  66  at the distal end for transmission of acoustic waves to the microphone  62 . The outer conductor  58  of cable  54  is connected to the boom component  52  utilizing an electrical connection  60 . The central conductor  56  is coupled to the boom component  50 . In one example, the electrical connections are formed using soldering techniques. 
     In one example, the first boom component  50  is a metal tube and the second boom component  52  is a metal tube, both of which are disposed within plastic housing  64 . In a further example, plastic housing  64  is a plastic material deposited upon the metal first boom component  50  and metal second boom component numerals  52 . 
     In a further example, the first boom component  50  is a formed of a conductive coating disposed on an interior surface of plastic housing  64  and the second boom component  52  is a conductive coating disposed on an interior surface of the plastic housing  64 . 
       FIG. 8  illustrates a simplified cross sectional diagram of a sleeve dipole antenna boom assembly  800  in which conductive elements are disposed within a plastic housing in a further example. Boom assembly  800  is substantially similar to boom assembly  500  described above in reference to  FIG. 7  except as follows. Instead of utilizing microphone  62 , boom assembly  800  utilizes a voice tube  70  disposed within the boom component  50  and boom component  52 . Voice tube  70  includes an opening porting to aperture  66  of plastic housing  64 . The voice tube  70  receives a user voice sound wave and transmits the sound wave to a microphone disposed at a headset housing coupled to the boom assembly  800 . 
       FIG. 9A  illustrates a front view of a headset  900  with a boom having a sleeve dipole antenna.  FIG. 9B  illustrates a rear view of the headset  900  shown in  FIG. 9A . Headset  900  includes a body  902  configured to be worn on a user ear and a boom  904  coupled to the body  902 . The boom  904  coupled to the body includes a radiating element, and a sleeve radiating element arranged to be electrically isolated from the radiating element. A RF feeding coaxial cable is disposed within the sleeve radiating element. The RF feeding coaxial cable includes an outer conductor and a central conductor; where the outer conductor is coupled to the sleeve radiating element. The central conductor is coupled to the radiating element. The radiating element has an electrical length of approximately one-quarter wavelength and the sleeve radiating element has an electrical length of approximately one-quarter wavelength. In one example, the radiating element and the sleeve radiating element form a boom  904  housing structure. In one example, the radiating element, sleeve radiating element, and RF feeding coaxial cable are disposed within an outer boom housing structure. 
     The boom  904  comprises an aperture  906  disposed at a distal end of the boom away from the body and arranged to receive a user voice sound wave. In one example, the aperture  906  is coupled to a voice tube disposed within the boom  904  which transmits the sound wave to a microphone disposed at the body  902 . 
     In a further example, the headset  900  includes a microphone disposed at a distal end of the boom away from the body  902 , and an electrical lead coupled to the microphone, the electrical lead disposed within the boom  904 . In one example, the length of the boom  904  is between approximately 60 millimeters and 80 millimeters, and may be configured to extend or retract in length. In a further example, the length of the boom  904  is 100-120 mm or longer. The plastic inside or outside can be as long as desired. Furthermore, the entire 60 mm or less antenna assembly can be located at the end of the boom. 
     In one example, the boom  904  is implemented as boom  500  as shown and described above in reference to  FIG. 5 . In this example, first boom component  28  shown in  FIG. 5  is implemented approximately at an area  908  and second boom component  30  is implemented approximately at an area  910  of boom  904 . In a further example, the boom  904  is implemented as boom  700  as shown and described above in reference to  FIG. 7 . In various embodiments, the antenna assembly boom  904  is implemented to transmit and receive on desired frequencies of the headset users, including Bluetooth bands, WiFi bands, digital enhanced cordless telecommunications (DECT) bands, or other frequency bands. 
       FIG. 10  illustrates a perspective view of a sleeve dipole antenna boom assembly  1000  in a further example. The boom assembly  1000  includes a RF feeding coaxial cable  1008  having an outer conductor  1012  and a central conductor  101 . 0 . The boom assembly  1000  includes a first boom component  1002 , the first boom component  1002  coupled to the central conductor  1010  and configured as an antenna radiating element. In the example shown in  FIG. 10 , a boom component  1004  is a metal tube having a metal cap  1006  on the end which is in proximity to boom component  1002 . Similarly, boom component  1002  is a metal tube having a metal cap  1 . 022  on the end which is in proximity to boom component  1004 . Both metal tubes are disposed within a plastic housing  1014 . 
     The boom assembly  1000  includes the second boom component  1004  electrically isolated from the first boom component  1002 , where the second boom component  1004  has a portion of the RF feeding coaxial cable  1008  disposed within. The second boom component  1004  is coupled to the coaxial cable outer conductor  1012  by soldering to metal cap  1006 , and is configured as an antenna sleeve radiating element. For example, a solder fillet may be utilized to solder the outer conductor  1012  to metal cap  1006 . The coaxial cable central conductor  1010  is soldered to metal cap  1022  of boom component  1002  so that boom component  1002  operates as a radiating element. 
     The boom assembly  1000  further includes a microphone  1016  disposed at a first end of the first boom component  1002 , and electrical leads  1018  coupled to the microphone, the electrical lead  1018  disposed within the first boom component  1002  and the second boom component  1004 . Microphone leads  1018  may run the length of the metal tubes through an aperture  1020  in the metal cap  1006  and corresponding aperture in metal cap  1022 . The first boom component  1002  has an electrical length of a one-quarter wavelength and the second boom component  1004  has an electrical length of a one-quarter wavelength. The plastic housing  1014  includes an aperture  1020  at the distal end for transmission of acoustic waves to the microphone  1016 . 
     In one example, the internal construction of boom assembly  1000  may be implemented with a flexible, rigid or semi-rigid coaxial cable. The tubes used for boom component  1002  and boom component  1004  are capped in metal, with the coaxial cable soldered with a fillet completely around the outer conductor and the entire assembly fit into a plastic tube or is embedded in an injection molded plastic part. The microphone leads  1018  pass through an aperture in the metal tube cap ends. This solution is advantageous for higher frequencies as the impedance is tightly controlled. 
     In a further implementation, a voice tube running the length of the metal tubes is used in place of microphone  1016  and leads  1018 , in which case aperture  1020  in metal cap  1006  and corresponding aperture in metal cap  1022  may be utilized by the voice tube. 
     While the exemplary embodiments of the present invention are described and illustrated herein, it will be appreciated that they are merely illustrative and that modifications can be made to these embodiments without departing from the spirit and scope of the invention. For example, the boom assemblies described herein may be used with a variety of type of electronic devices. Thus, the scope of the invention is intended to be defined only in terms of the following claims as may be amended, with each claim being expressly incorporated into this Description of Specific Embodiments as an embodiment of the invention.