Abstract:
An antenna/push-button assembly includes a first contact, a second contact movable relative to said first contact, and a button member including an integral antenna. The button member is movable to engage the second contact with the first contact. The antenna may be a patch antenna. A portable telecommunications device includes an antenna/push-button assembly comprising a button member. The button member includes an integral antenna. The button member is operable to control a function of the device.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of communications and more particularly to telecommunications devices including antennas. 
     BACKGROUND OF THE INVENTION 
     Personal telecommunications devices such as satellite radiotelephones, combined satellite and cellular radiotelephones, global positioning systems (GPS) and the like often employ one or more patch antennas for receiving and/or sending radio signals. For example, it has been proposed to provide global positioning features in cellular radiotelephones. See, e.g., U.S. Pat. No. 5,235,633 to Dennison et al. and U.S. Pat. No. 5,625,668 to Loomis et al., the disclosures of which are hereby incorporated herein in their entireties by reference. 
     Portable radiotelephones including GPS receivers have typically used an additional antenna to provide GPS reception. For example, quadrifilar helix antennas extending from the radiotelephone body have been used. Quadrifilar helix antennas may be difficult to integrate into an industrial design. 
     In co-assigned and co-pending application Ser. No. 09/193,587, filed Nov. 17, 1998, the disclosure of which is hereby incorporated herein in its entirety, there are disclosed radiotelephones including GPS receivers which incorporate patch antennas to receive global positioning system signals. Locating the patch antenna in/on the radiotelephone body in a manner which does not significantly affect the dimensions thereof is discussed. However, in order to do so, the patch antenna is perforated so as not to interfere with other functions or components of the radiotelephone such as speakers and buttons. Such perforations may necessitate special tuning of the antenna and/or reduce the performance of the antenna. 
     It is often difficult or impractical to find space for a patch antenna on the increasingly small handsets of radiotelephones and GPS devices. Often, the overall size or range of functionality of the device must be designed to accommodate the patch antenna(s). In some cases, the provision of a patch antenna may simply be impractical. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an antenna/push-button assembly which reduces or eliminates the problems associated with antennas such as patch antennas in small telecommunications devices as discussed above. The antenna/push-button assembly makes improved use of the available space of the device by integrating the antenna and one or more push-button functions. 
     According to an aspect of the present invention, an antenna/push-button assembly includes a first contact, a second contact movable relative to the first contact, and a button member. The button member includes an integral antenna. The button member is movable to engage the second contact with the first contact. The antenna may be a patch antenna. 
     Preferably, the assembly includes a spring member operative to bias the second contact away from the first contact. The button member may include a button cover covering at least a portion of the antenna. Preferably, the antenna is a patch antenna including a dielectric substrate having upper and lower opposed surfaces, an electrically conductive patch element disposed on the upper surface, and a ground plane layer disposed on the lower surface. The assembly may include a flexible grounding connector having a first end connected to the ground plane layer and a second end adapted to be connected to a supplemental ground plane spaced from the ground plane layer. An antenna feed line may extend through the ground plane layer and the dielectric substrate, the feed line being electrically coupled to the patch element. 
     According to a further aspect of the present invention, a portable telecommunications device includes an antenna/push-button assembly comprising a button member. The button member includes an integral antenna. The button member is operable to control a function of the telecommunications. The antenna may be a patch antenna. 
     According to a further aspect of the present invention, a portable telecommunications device includes a circuit board and an antenna/push-button assembly. The antenna/push-button assembly includes a first contact mounted on the circuit board, a second contact movable relative to the first contact, and a button member. The button member includes an integral antenna. The button member is movable to engage the second contact with the first contact. The antenna may be a patch antenna. 
     The portable telecommunications device may include: a transceiver that transmits and receives radiotelephone communications; a processor coupled to the transceiver that processes the radiotelephone communications transmitted and received by the transceiver; a speaker coupled to the processor that generates sound responsive to the received radiotelephone communications; and a microphone coupled to the processor that generates electrical signals for the transmitted radiotelephone communications responsive to outside sound. The antenna includes a conductive layer that receives electromagnetic signals. The antenna is coupled to the processor and/or the transceiver. The antenna may be a patch antenna. 
     The telecommunications device may include a housing body, wherein the circuit board is disposed in the housing body. The button member is movably received in the housing body. 
     The objects of the present invention will be appreciated by those of ordinary skill in the art from a reading of the figures and the detailed description of the preferred embodiment which follow, such description being merely illustrative of the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a radiotelephone including an antenna/push-button assembly according to the present invention; 
     FIG. 2 is a block diagram of the radiotelephone of FIG. 1; 
     FIG. 3 is an enlarged, partial top plan view of the antenna/push-button assembly of the radiotelephone of FIG. 1; 
     FIG. 4 is an enlarged, partial, cross-sectional view of the radiotelephone of FIG. 1 taken along the line  4 — 4  of FIG. 1; 
     FIG. 5 is an enlarged, partial, cross-sectional view of an alternative antenna/push button assembly according to the present invention mounted in the radiotelephone and taken along a line corresponding to the line  4 — 4  of FIG. 1; 
     FIG. 6 is an enlarged, partial, cross-sectional view of a further alternative antenna/push button assembly according to the present invention mounted in the radiotelephone and taken along a line corresponding to the line  4 — 4  of FIG. 1; and 
     FIG. 7 is an enlarged, partial, cross-sectional view of a further alternative antenna/push button assembly according to the present invention mounted in the radiotelephone and taken along a line corresponding to the line  4 — 4  of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the thicknesses of layers and regions of the cross sections are exaggerated for clarity. Like numbers refer to like elements throughout. It will also be understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
     An antenna/push-button assembly according to the present invention may be incorporated into any suitable device which requires or makes advantageous use of both an antenna and a push-button. It is particularly contemplated that the antenna/push-button assembly may include a patch antenna and be employed in a radiotelephone having GPS, for example as described hereinbelow. However, it will be appreciated by those of skill in the art upon reading the description herein that the antenna/push-button assembly may be used in numerous other devices. Such devices include, but are not limited to, GPS-only devices, radiotelephones including both cellular and satellite processing capabilities, radiotelephones including only cellular capabilities, and wireless network devices. 
     A cellular radiotelephone  10  including an antenna/push-button assembly  100  according to the present invention is illustrated in FIGS. 1-4. As shown in FIG. 2, the cellular radiotelephone  10  includes a transceiver  21  for transmitting and receiving cellular radiotelephone communications through an antenna  23 , and a processor  25  for processing the communications transmitted and received by the transceiver  21 . In addition, a user interface  27  is coupled with the processor  25 , and the user interface can include the antenna/push-button assembly  100  (see FIG.  1 ), a keypad  29 , a display  31 , a microphone  33 , and a speaker  35 . Accordingly, the radiotelephone  10  can accept user speech through the microphone  33  for transmission to a radiotelephone communications system, and reproduce speech received from a distant party over the radiotelephone communications system using the speaker  35 . Radiotelephone information can be provided to the user through the display  31 , and user input can be accepted through the keypad  29  and the antenna/push-button assembly  100 . 
     In addition, the radiotelephone  10  includes a GPS receiver  37  and a GPS patch antenna  120 . The GPS receiver  37  can thus accurately determine the geographic position of the radiotelephone  10 , and provide the geographic information to the radiotelephone processor  25 . Accordingly, this geographic information can be provided to the radiotelephone user either visually through the display  31  or audibly through the speaker  35 . The geographic information can also be transmitted through the transceiver  21  and the antenna  23  to the radiotelephone communications system. For example, the geographic information can be transmitted during a “911” call to assist an emergency response by police, fire, and/or rescue personnel. The geographic information can also be used, for example, to make call management decisions as discussed in U.S. Pat. No. 5,235,633, spoken with a speech synthesizer as discussed in U.S. Pat. No. 5,625,668, or otherwise communicated to the user of the radiotelephone. 
     As will be understood by those having skill in the art, the GPS receiver  37 , the transceiver  21 , and the processor  25  can be provided separately as shown in FIG.  2 . Alternately, two or more of these elements can be provided together. For example, the processor can be defined as including one or both of the GPS receiver and the transceiver, and/or the transceiver can be defined as including the GPS receiver. These elements are shown separately for the sake of clarity of this disclosure and not for purposes of limitation. Moreover, these elements can be provided individually or in combination, and can be provided as one or more custom and/or standard integrated circuit devices and/or discrete devices running firmware and/or software. 
     As shown in FIG. 1, the radiotelephone includes a body  41  housing the antenna/push-button assembly  100 , the display  31 , the keypad  29 , the microphone  33 , and the antenna  23  as shown. The housing also encloses the GPS receiver  37 , the transceiver  21 , a printed circuit board (PCB)  60  (see FIG.  4 ), the processor  25 , and the speaker  35  which are not visible in the perspective view of FIG.  1 . 
     The radiotelephone body  41  includes a front face  43  which is held to the user&#39;s head when talking. Accordingly, the speaker  35  is mounted adjacent the front face  43 , and holes  45  are provided in the front face  43  adjacent the speaker  35  to allow sound from the speaker to pass therethrough. A moveable flip portion  49  extends the front face  43  when opened as shown, and the microphone  33  is included in the main portion of the radiotelephone body  41 . A channel  51  through the flip portion  49  conducts sound from the holes  47  to the microphone  33 . When closed, the flip portion  49  covers a portion of the radiotelephone body. The front face of the radiotelephone body also includes the display  31  and the keypad  29 . The flip portion  49  covers the keypad  29  when closed. The flip portion  49  may be extended (not shown) to cover the display  31  when closed as well. 
     With reference to FIGS. 3 and 4, the antenna/push-button assembly  100  is mounted in a hole  44  in the front face  43 . The antenna/push-button assembly  100  includes a button member  111 . The button member includes a button cover  110  and a patch antenna  120 . 
     The patch antenna  120  includes a dielectric substrate  124  having an upper surface  124 A and a lower surface  124 B. A conductive antenna patch element  122  is secured to the upper surface  124 A of the dielectric substrate  124 . A ground plane layer  126  is secured to the lower surface  124 B of the dielectric substrate  124 . The ground plane layer  126  has a hole  126 A formed therein and a lower surface  126 B. The area of the ground plane layer  126  is substantially the same as that of the dielectric substrate  124  with the exception of the hole  126 A. Alternatively (not shown), the ground plane layer may be substantially larger than the dielectric substrate. The dielectric substrate  124  is preferably formed of loaded ceramic or air. The conductive patch element  122  is preferably formed of copper. The ground plane layer  126  is preferably formed of copper. 
     The button cover  110  is secured to the patch antenna  120  such that the entirety of the patch antenna  120  extending above the housing  43  is enveloped in and protected by the button cover  110 . Preferably, the button cover  110  is formed from a plastic or other material which does not significantly attenuate the GPS signals (typically 1575.42 MHz) received by the patch antenna  120 . Indicia  112  may be provided on the button cover  110  to indicate to the user the button&#39;s function. 
     The conductive patch element  122  is fed by a flexible coaxial cable  150 . More particularly, the center conductor  152  of the coaxial cable  150  extends through the hole  126 A and the dielectric substrate  124  and is electrically connected to the patch element  122 . The center conductor  152  thereby serves as the feed line. The size and shape of the element  122  tunes the antenna  120 . The placement of the connection between the feed line  152  and the element  122  determines impedance matching and antenna polarization. 
     The performance of the patch antenna  120  is sensitive to the size and shape of the ground plane. In general, the antenna gain is improved when a larger ground plane is used. The ground plane layer  126  is connected to the larger ground plane of the PCB  60  by coil springs  146 . Each of the springs  146  is electrically connected and secured, for example by soldering, to the lower surface  126 B. The electrical reactance of the springs  146  should not be significant for the chosen frequency. By electrically connecting the ground plane layer  126  and the PCB ground plane  60 , the springs  146  allow the patch antenna  120  to make use of the larger ground plane of the PCB  60 . The springs  146  also ensure that the patch antenna ground plane layer  126  and the PCB ground plane are at the same electrical potential to prevent creation of undesirable radiating modes. The springs  146  provide connections to the PCB ground plane  60  without unduly hindering the button action of the patch antenna/push-button assembly  100 , as discussed below. Alternatively, the springs  146  may bias or assist in biasing the button  111  away from the PCB  60 . The springs  146  may be replaced by other suitable devices which provide the requisite electrical connection while allowing the push-button movement. 
     The construction and operability of the patch antenna  120  will be apparent to those of skill in the art upon reading the foregoing. Additionally, the antenna/push-button assembly  100  serves as a push-button of the radiotelephone  10  to allow user input and control. For example, the button member  111  may be depressed by the user to generate a signal (e.g., to turn on the device power or initiate a GPS request). 
     The coaxial cable  150  is secured by suitable means such as conductive adhesive or solder to the lower surface  126 B of the patch antenna  120 . A resilient membrane spring  144  is mounted on the PCB  60  and secured to the coaxial cable  150 . A button contact  140  is secured to the membrane spring  144  and a contact pad  142  is mounted on the PCB  60 . The button contact  140  and/or the contact pad  142  are electrically connected to an electrical circuit of the radiotelephone  10  such that their engagement and disengagement actuates the chosen function. For example, the engagement of the contact  140  and the contact pad  142  may operate to turn the phone on and off or to activate connection with a network. Suitable arrangements and components for such control buttons or switches are well-known in the art. 
     The membrane spring  144  biases the button member  111  upwardly away from the PCB  60  into the extended, ready position as shown in FIG.  4 . When the user pushes the button member  111  in the direction D, the membrane spring  144  is compressed and the contact  140  engages the contact pad  142 . Upon release of the button member  111 , the membrane spring  144  applies an upward force so that the assembly  100  resumes the extended position and contact between the contact  140  and the contact pad  142  ceases. In this manner, the user may selectively engage the contacts  140 ,  142  with one another and thereby selectively actuate the associated function of the radiotelephone  10 . 
     The antenna/push-button assembly  100  provides a number of advantages. Neither the performance of the antenna nor the performance of the push button is compromised. Space on the radiotelephone  10  and, in particular, premium space on the front panel of the radiotelephone, is conserved. The patch antenna  120  can be provided without significantly affecting the dimensions of the radiotelephone. The overall cost of providing the patch antenna function and the push-button function may be reduced. A sufficient ground plane is provided for the antenna. The feed to the patch antenna  120  does not hinder operation of the push-button function. 
     Preferably, the function of the radiotelephone  10  actuated by compressing the button member  111  is selected such that the patch antenna  120  is not needed while the button member  111  is being compressed. For example, the push-button action of the assembly  100  may initiate a GPS function such that the button member  111  need only be momentarily compressed and released (whereupon the user will typically remove his/her finger). This configuration can prevent the presence of a user&#39;s finger on the assembly  100  when compressing the button member  111  from degrading antenna performance. 
     Notably, the patch antenna  120  discussed above is oriented substantially parallel to the front face  43  of the radiotelephone body  41 . Accordingly, the radiotelephone  10  is preferably held with the front face  43  substantially parallel to the ground and facing upward when receiving GPS signals from GPS satellites. This orientation gives the patch antenna a good, unobstructed view of the GPS satellite. 
     With reference to FIG. 5, an antenna/push-button assembly  200  according to a second embodiment is shown therein. The assembly  200  is mounted in the radiotelephone  10  in place of the antenna/push-button assembly  100  and the view of FIG. 5 is a cross-sectional view corresponding to that of FIG.  4 . The assembly  200  includes elements  210 ,  211 ,  220 ,  222 ,  224 ,  224 A,  224 B,  226 ,  226 A,  226 B,  240 ,  242 ,  244  and  246  corresponding to elements  110 ,  111 ,  120 ,  122 ,  124 ,  124 A,  124 B,  126 ,  126 A,  126 B,  140 ,  142 ,  144  and  146  of the assembly  100 . 
     The antenna/pushbutton assembly  200  differs from the assembly  100  in that the patch antenna  220  is fed by a collapsible “pogo” pin connector  260 . The connector  260  has a base  264  electrically connected to an antenna feed connection on the PCB  60 , and a pin  262  extending through the hole  226 A and the substrate  224  and electrically connected to the base  264  and the conductive antenna patch element  222 . The pin  262  is joined to the base  264  such that the pin  262  may be compressed into the base  264 . Suitable connectors  260  include product no. RMP-122 available from the ECT Contact Division of Everett Charles Technologies of Pomona, Calif. 
     It will be appreciated by those of skill in the art that the assembly  200  will function in the same manner as the assembly  100 , the membrane  244  being compressible in the direction D to allow contact between the button contact  240  and the contact pad  242  and biasing the button contact  240  away from the contact pad  242 . The provision of the pogo pin connector  260  may allow the assembly  200  to be manufactured with greater ease and less cost than the assembly  100 . 
     With reference to FIG. 6, an antenna/push-button assembly  300  according to a third embodiment is shown therein. The assembly  300  is mounted in the radiotelephone  10  in place of the antenna/push-button assembly  100  and the view of FIG. 6 is a cross-sectional view corresponding to that of FIG.  4 . The assembly  300  includes elements  310 ,  311 ,  320 ,  322 ,  324 ,  324 A,  324 B,  326 ,  326 A,  326 B,  340 ,  342  and  346  corresponding to elements  110 ,  111 ,  120 ,  122 ,  124 ,  124 A,  124 B,  126 ,  126 A,  126 B,  140 ,  142  and  146  of the assembly  100 . 
     The antenna/push-button assembly  300  differs from the assembly  100  in that the patch antenna  320  is fed by a conductive spring finger connector  370  and no membrane spring is provided. The connector  370  has a resilient spring portion  374  which biases the button member  311  into the extended position of FIG. 6. A lead  372  extends through the hole  326 A and the dielectric substrate  324  and electrically connects the connector  370  to the patch element  322 , thereby connecting the patch element  322  to an antenna feed connection on the PCB  60 . The button contact  340  is mounted on the portion  372 . A non-conductive spacer  373  is interposed between the contact  340  and the portion  372  to prevent the antenna from short circuiting when the button member  311  is pressed. 
     It will be appreciated by those of skill in the art that the assembly  300  will function in the same manner as the assembly  100 , the spring finger portion  374  being compressible in the direction D to allow contact between the button contact  340  and the contact pad  342  and biasing the contact  340  away from the contact pad  342 . The provision of the spring finger connector  370  allows the assembly  300  to be manufactured conveniently and inexpensively. 
     With reference to FIG. 7, an antenna/push-button assembly  400  according to a fourth embodiment is shown therein. The assembly  400  is mounted in the radiotelephone  10  in place of the antenna/push-button assembly  100  and the view of FIG. 7 is a cross-sectional view corresponding to that of FIG.  4 . The assembly  400  includes elements  410 ,  411 ,  420 ,  422 ,  424 ,  424 A,  424 B,  426 ,  426 A,  426 B and  446  corresponding to elements  110 ,  111 ,  120 ,  122 ,  124 ,  124 A,  124 B,  126 ,  126 A,  126 B and  146  of the assembly  100 . 
     The assembly  400  is a two position “rocker” button. The button member  411  may be pressed on one side  411 A in the direction D 1  to actuate one function and may be pressed on the other side  411 B in the direction D 2  to actuate another function, for example. 
     The antenna patch element  422  is electrically connected to a feed on the PCB  60  by a non-collapsible hinge connector  480  having a base  484  (which is electrically connected to the antenna feed) and a pin  482  which serves as the antenna feed line. The pin  482  is hingedly connected to the base  484  by a pivot pin  485 . The pivot pin  485  allows the button member  411  to pivot about the base  484  in directions P 1  and P 2 . 
     A first membrane spring  444 A biases a first button contact  440 A away from an associated contact pad  442 A on the PCB  60 . A second membrane spring  444 B biases a second button contact  440 B away from an associated contact pad  442 B. 
     In use, the user may press on the first side  411 A of the button member  411  to cause the button member  411  to pivot about the pivot pin  485  and compress the membrane  444 A so that the button contact  440 A engages the contact pad  442 A. Alternatively, the user may press on the side  411 B of the button member  411  to engage the button contact  440 B with the contact pad  442 B. 
     While the button contacts  140 ,  240 ,  340 ,  440 A,  440 B as described above are mounted at preferred locations, the button contacts may alternatively be mounted at other locations on the button members  111 ,  211 ,  311 ,  411 . For example, the button contacts may be secured to the lower surfaces  126 B,  226 B,  326 B,  426 B of the ground layers  126 ,  226 ,  326 ,  426 . In this case, electrically insulative spacers are preferably provided between the ground layers and the button contacts. Additionally, rather than being mounted on the button members  111 ,  211 ,  311 ,  411 , the button contacts  140 ,  240 ,  340 ,  440 A,  440 B may be mounted on other components or additional linkages (not shown). For example, the button contacts may be mounted free of the button members except that displacement of the associated button member causes, by direct abutment or via a linkage, displacement of the button contact  140 ,  240 ,  340 ,  440 A,  440 B toward the base contact  142 ,  242 ,  343 ,  442 A,  442 B. More particularly, the button contacts may be secured to the membrane springs with neither the button contacts nor the membrane springs being secured to the associated button members. 
     In the patch antenna/push-button assemblies described above, the feed lines are directly connected to the patch elements. Alternatively, the feed lines may be spaced from but electromagnetically coupled to the patch elements. 
     The membrane springs  144 ,  244 ,  444 A,  444 B may be omitted by suitably designing the springs  146 ,  246 ,  446  to provide the desired biasing of the respective buttons  111 ,  211 ,  411 . 
     While radiotelephones including patch antennas according to the present invention have been discussed with reference to cellular radiotelephones, the patch antennas of the present invention can be used with other radiotelephones such as satellite radiotelephones or dual mode radiotelephones capable of communicating with terrestrial and satellite communications systems, as well as radiotelephones capable of communicating with other types of terrestrial communications systems. 
     It is further contemplated that antennas of other types may be incorporated into an antenna/push-button assembly according to the invention in place of a patch antenna with suitable modification. For example, a wire antenna, a monopole antenna, a loop antenna, a dielectric resonator antenna (DRA), a planar inverted F antenna (PIFA), or a quadrifilar helix antenna may be used. The antenna/push-button assemblies are particularly advantageous when incorporating patch antennas because patch antennas allow for a desirably low profile. While the radiotelephone  10  has the additional antenna  23  for receiving and transmitting cellular radiotelephone communications, it is contemplated that an antenna serving this function may be incorporated into an antenna/push-button assembly according to the present invention. 
     The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the appended claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.