Abstract:
A mobile phone including a handset having a transceiver adapted for selective communication in cellular and satellite modes. The handset includes a cellular antenna adapted to receive cellular wavelength signals, a connector for a satellite antenna, and a switch adapted to selectively connect either the cellular antenna or the connector to the transceiver. The satellite antenna is adapted for selective connection to the connector of the mobile phone handset, the satellite antenna being adapted to receive satellite wavelength signals. The satellite antenna includes a cavity in a first portion adapted to receive and frictionally secure to the cellular antenna, and a plunger is adapted to engage the switch to disconnect the cellular antenna from, and connect the satellite antenna to, the transceiver when the satellite antenna is secured to the handset connector.

Description:
BACKGROUND OF THE INVENTION 
     The present invention is directed toward wireless communication devices, and more particularly toward wireless communication devices intended to transmit and receive signals in different modes operating in different bandwidths, such as cellular and satellite communications. 
     Wireless communication devices such as cellular and satellite telephones communicate via radio signals. In order to properly receive and transmit signals in a particular system of communication (e.g., cellular or satellite), it is necessary to have an appropriate antenna which is tuned to work with the frequencies/wavelengths in the bandwidth of the system with which the device is designed to be used. With devices intended to be used with satellite systems, the size of the antenna required on the portable handsets in the system can be fairly large (e.g., Cuban-cigar like). Such an antenna can be particularly detrimental for portable handsets given its size and weight. Wireless communication device users are more and more coming to expect to be able to unobtrusively slip the handsets into their pockets (as is today common for cellular telephones), and the inability to do so with satellite communication devices which require such large antennas has, along with other factors, significantly obstructed the market acceptance of such devices. Dual mode devices, which may be operated with both cellular and satellite systems, face similar problems, as they also require one or more antennas tuned to operate properly with both systems, including a large antenna for receiving signals in the satellite system bandwidth. 
     The present invention is directed toward overcoming one or more of the problems set forth above. 
     SUMMARY OF THE INVENTION 
     In one aspect of the invention, a mobile communication device is provided, including a portable handset including a transceiver adapted for selective communication in first and second wireless modes. The handset includes a first antenna adapted to receive and transmit wireless signals having a wavelength in a first range, a connector, and a switch adapted to selectively connect either the first antenna or the connector to the transceiver. A second antenna is also provided and adapted for selective connection to the connector of the portable handset. The second antenna is adapted to receive and transmit signals having a wavelength in a second range, the second range being wavelengths different than the wavelengths in the first range. 
     In one form of this aspect of the invention, the second antenna includes a pocket clip whereby the mobile communication device user may securely carry the second antenna in a user&#39;s pocket when the second antenna is not connected to the portable handset connector. 
     In another form, the connector includes electrical contacts on the portable handset adapted to connect the second antenna to the transceiver when the second antenna is connected to the handset connector. 
     In still another form, a cavity is provided in the second antenna and adapted to receive the first antenna, the first antenna being frictionally secured to the second antenna when received in the second antenna cavity. In a related form, the second antenna cavity has at least a portion smaller than the first antenna, wherein at least one of the second antenna cavity and the first antenna is elastically deformable. 
     In yet another preferred form, the first antenna is tuned to receive and transmit signals in the first range and is further adapted to receive and transmit a broad band of signals including signals in the second range. 
     In other preferred forms, a plunger is adapted to engage the switch to disconnect the first antenna from the transceiver and connect the second antenna to the transceiver when the second antenna is secured to the portable handset connector, and the connector comprises axially spaced joining members. A preferred form is also used with cellular signals having wavelengths in the first range and satellite signals having wavelengths in the second range, with a mode switch provided for selectively switching the transceiver between cellular and satellite modes. 
     In still another preferred form, the second antenna includes first and second portions, with the first portion adapted for selective connection to the connector of the portable handset, the first portion including a member adapted to connect to the switch when the second antenna is connected to the connector, and the second portion including antenna radiating elements. A pivotable connection is provided between the first and second portions, with the pivotable connection adapted to allow the second portion to be positionally adjusted relative to the first portion. In further preferred forms, a coaxial cable extends from the first portion member to the antenna radiating elements, the coaxial cable connecting the antenna radiating elements to the switch when the second antenna is connected to the connector, and the first and second portions are substantially longitudinal with the pivotal connection connecting the first and second portions substantially end to end whereby the positional adjustment is pivoting of one second antenna portion relative to the other second antenna portion about an axis substantially normal to the longitudinal direction of both the second antenna first and second portions. 
     In another aspect of the present invention, a mobile phone is provided including a handset including a transceiver adapted for selective communication in cellular and satellite modes. The handset includes a cellular antenna adapted to receive and transmit cellular wavelength signals, a connector for a satellite antenna, and a switch adapted to selectively connect either the cellular antenna or the connector to the transceiver. A satellite antenna is also provided and adapted for selective connection to the connector of the mobile phone handset, the satellite antenna adapted to receive and transmit satellite wavelength signals. 
     Preferred forms of this aspect of the invention include the above described preferred forms of the first described aspect of the invention as used in cellular and satellite systems. 
     Another preferred form of this aspect of the present invention is that the cellular antenna is further adapted to receive satellite page signals. 
     In yet another aspect of the present invention, a method of operating a mobile communication device is provided, including the steps of ( 1 ) receiving and transmitting cellular telephone signals and control satellite signals with a first antenna connected to a transceiver of the mobile communication device, ( 2 ) selectively connecting a second antenna to the transceiver when choosing to receive and transmit traffic channel satellite signals, the connecting step automatically disconnecting the first antenna from the transceiver, whereby the first antenna is tuned to cellular and satellite telephone signal wavelengths and the second antenna is tuned to satellite signal wavelengths. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of a cellular telephone handset embodying the present invention in a cellular mode; 
     FIG. 2 is a plan view of the cellular telephone handset of FIG. 1 in a satellite mode with a satellite mode antenna attached; 
     FIG. 3 is a side view of a cellular telephone handset similar to that shown in FIG.  1  and illustrating exemplary electromechanical components according to the present invention; 
     FIG. 4 is a view of the connecting ends of the handset of FIG.  3  and the associated satellite mode antenna; 
     FIG. 5 is a plan view of the handset of FIG. 3 illustrating the satellite mode antenna connected to the handset; and 
     FIG. 6 is a side view similar to FIG. 3 with the satellite mode antenna attached to the handset. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1-2 generally illustrate a wireless portable handset  10  embodying the present invention. As illustrated, the handset  10  includes a speaker  11 , a display  12 , a touch pad input  14 , a microphone  15 , and a cellular mode antenna  16 . Once the present invention is fully understood, it will be recognized by those skilled in the art that the handset  10  could be provided with a wide variety of features and functions beyond those described herein, which description is focused on the features relating particularly to the invention. 
     The cellular mode antenna  16  is tuned to transceive radio signals in the cellular band (i.e., signals having frequencies/wavelengths in the bandwidth allocated to the cellular telephone system with which the handset  10  is expected to be used). 
     As will be more fully understood hereafter, the handset  10  of the present invention is intended to be used with two different types of systems, specifically a terrestrial cellular system and a satellite system. These systems typically operate over different signal bandwidths (e.g., on the order of 900 megahertz for terrestrial cellular systems and 1.6 gigahertz for satellite systems), and thus the cellular mode antenna  16  will be tuned for the cellular bandwidth but not for the satellite bandwidth. 
     However, it should be understood that in the preferred mode as used with mobile satellite systems equipped with high penetration paging modes, such as ACeS (Asian Cellular Satellite system), the cellular mode antenna  16  can be broadbanded so that it will also function adequately as a paging antenna for satellite mode. In such systems, the satellite system sends paging messages (indicating, e.g., that there is an incoming call to the handset over the satellite system) at significantly greater power than normal communication signals. Such a power increase enables the satellite paging signal to be adequately received even though the cellular antenna  16  is less than optimal for signals in the satellite bandwidth, and the transceiver in the handset  10  will be able to receive the page when the transceiver is operating in satellite mode (i.e., is looking for signals in the satellite bandwidth). 
     While the invention is described herein with particular reference to dual modes of operation with both cellular and satellite systems (e.g., terrestrial GSM and ACeS), it should be understood that the invention in broad scope may be used with any combination of systems using different bandwidths where different antennas are required for the different bandwidths, and is particularly advantageous in those circumstances where one of the different antennas adds weight or bulk to the handset  10 . 
     The outer surface of the radome  18  covering the cellular mode antenna  16  defines a particular shape, such as a cylinder, and a satellite mode antenna  26  is provided with a suitably matching cavity  30  (see FIG. 2) so that the satellite mode antenna  26  may be suitably secured onto the cellular mode antenna  16  with the cellular mode antenna  16  acting as a mechanical support for the satellite mode antenna  26  (such connection is also further described below particularly in FIG.  4 ). Specifically, in one preferred embodiment, the cavity  30  and radome  18  are matched so that there is a frictional connection which will secure the two together (e.g., with the cavity  30  deformable but slightly smaller than the radome  18 ), such as the cap secured onto a magicmarker. However, it should be understood that it would be within the scope of the present invention to provide other means of connection including, for example, a structure in which one or both of the components (antenna  16  and cavity  30 ) are elastically deformable whereby a detent or similar structure will deform when the two are being connected and then snap into place when aligned with a matching recess in the other component. 
     In a preferred form as illustrated in FIG. 2, the satellite mode antenna  26  includes a suitable pivotal connection  34  allowing the two generally longitudinally extending end portions  36 ,  38  of the satellite mode antenna  26  to pivot relative to one another about an axis generally perpendicular to the longitudinal direction of the end portions  36 ,  38 . In the preferred form, the pivotal connection  34  has no exposed openings or the like which might pinch a user or catch the user&#39;s hair. 
     The satellite mode antenna  26  includes a pocket clip  44  whereby the handset user may securely carry the satellite mode antenna in his or her shirt pocket like a pen or standard magic marker when the satellite mode antenna  26  is not in use (as shown in FIG.  1 ). As illustrated in FIG. 2, the clip  44  is on the radome end portion  38 , although it should be understood that the clip  44  could also be provided on the end portion  36  having the cavity  30 . 
     FIGS. 3-6 illustrate further electromechanical details of a preferred embodiment of the invention described generally above with respect to FIGS. 1-2. Further, for simplicity of illustration, certain internal components are not illustrated as hidden inside the handset  10 ′, although those skilled in the art will readily recognize the preferred location of such components inside the handset housing. 
     As illustrated in FIG. 3, the handset  10 ′ includes a mechanical switch  50  which connects the antenna radiating elements  52  of the cellular mode antenna  16  to a mode selection switch  54 . The mode selection switch  54 , which may be changed by user input (e.g., through the touch pad input  14 ) or may be changed automatically by the handset  10 ′ in response to the user menu settings and signal detection algorithms, switches the mode of operation of the transceiver  56  connected to the antenna  16  (or  26  as described in FIG. 5) (the transceiver  56  is described herein in only general terms; suitable transceivers and related components appropriate to transceive radio signals according to the standard of the wireless systems with which the handset is being used will be readily recognized by those skilled in the art once a full understanding of the invention is obtained, and therefore no detailed description of those elements is set forth herein). 
     For example, as illustrated in FIG. 3, the switch  54  is set to the cellular mode terminal  58 , so that the transceiver  56  is transceiving cellular band signals from the cellular mode antenna  16 . The switch  54  could be changed to the satellite mode terminal  60 , in which case the transceiver  56  would transceive satellite band signals from the cellular mode antenna  16  (as previously described, though the cellular mode antenna  16  may not be optimum for signals in the satellite bandwidth, it should still adequately receive paging signals in systems in which the power of the paging signals is stepped up by the satellite). 
     FIG. 4 illustrates one preferred mechanical connection between the handset  10 ′ and the satellite mode antenna  26 . Specifically, the handset  10 ′ includes the cellular mode antenna  16  which is received inside a cavity  30  in the satellite mode antenna  26  as previously described. An electrical connector  66  is also provided in the handset  10 ′ and includes suitable contacts to connect with electrical contacts on the satellite mode antenna  26  as described further below. A plunger  70  projects from the bottom of the satellite mode antenna  26  and is received in a recess  72  in the handset  10 ′ to automatically change the position of the mechanical switch  50  as is also described below. Additional mechanical components such as a pin  74  and recess  76  may also be provided to further securely connect the satellite mode antenna  26  to the handset  10 ′ when desired and to assist in bearing stresses which might be incurred to protect the cellular mode antenna  16  and plunger  70  from damage. It should be recognized, however, that connectors between the handset  10 ′ and the satellite mode antenna  26  which are different from those illustrated in FIG. 4 may be used within the scope of the present invention. 
     The satellite mode antenna  26  is illustrated as connected to the handset  10 ′ in FIGS. 5-6. As best illustrated in FIG. 6, the satellite mode antenna  26  includes suitable antenna radiating elements  80  for the satellite system with which the handset  10 ′ is designed to be used. In the preferred embodiment, the satellite mode antenna radiating elements  80  comprise a Quadrifilar Helix (QFH) antenna tuned to transceive radio signals in the satellite bandwidth. Design of QFH antennas is disclosed in U.S. Pat. Nos. 5,896,113 (“Quadrifilar Helix Antenna with Switching Diodes”), U.S. Pat. No. 5,909,196 (“Quadrifilar Helix Antenna with Integral Impedance-Matching”) and U.S. Pat. No. 5,920,292 (“Dual Band Quadrifilar Helix Antenna with Integral Half Duplex”), the full disclosures of which are hereby incorporated by reference. However, is should be understood that still other antenna radiating element designs adequately tuned to transceive signals in the satellite (or other second system) bandwidth would be usable with the present invention. Note that with the illustrated configuration, the satellite mode antenna radiating elements  80  are located above where the user&#39;s ear would typically be located, thereby minimizing any interference potentially resulting from the mass of the user&#39;s head. 
     A suitable electrical connector such as coaxial cable  84  extends from the radiating elements  80  to the end of the satellite mode antenna  26  and contact the electrical connector  66  in the handset  10 ′. The plunger  70  engages the mechanical switch  50  so as to automatically disconnect the cellular mode antenna  16  when the satellite mode antenna  26  is attached to the handset  10 ′ as shown in FIG. 6, so that the satellite mode antenna radiating elements  80  are connected to the mode selection switch  54  which, with the satellite mode antenna  26  attached, is connected to the satellite mode terminal  60 . 
     Though it is desirable that the mode selection switch  54  be changeable through user input (so that either mode can be selected by the user when the cellular mode antenna  16  is connected through switch  50  as previously described), it would be within the scope of the present invention to also have the mode selection switch  54  suitably switched automatically to the satellite mode terminal  60  when the satellite mode antenna  26  is attached. 
     It should also be understood that both switches  50 ,  54  could be of a different configuration than that shown in the Figures. For example, the mode selection switch  54  could be simply programming in the processor of the handset  10 ′ rather than the mechanical switch structure shown for simple illustration purposes in FIGS. 3 and 6. Further, the mechanical switch  50  could be any other switch (not necessarily even categorized as a mechanical switch) which will electrically couple the satellite mode antenna radiating elements  80  to the transceiver  56  and disconnect the cellular antenna radiating elements  52  from the transceiver  56 , preferably automatically, when the satellite mode antenna  26  is attached to the handset  10 ′. 
     Another approach could be to do away with switch  50  and electrical contact point  66  altogether. Instead, the antenna  16  on handset  10  is appropriately dual banded to transceive both the cellular band frequencies and the satellite band frequencies. When operating in the satellite band frequencies, the satellite mode antenna  26  can be attached mechanically onto the handset antenna  16  by fitting antenna  16  into the cavity  30  of satellite mode antenna  26 . The electrical energy can then be coupled to satellite antenna  26  to and from the handset antenna  16  by inductive and/or capacitive means as will be apparent to those skilled in the art. Such means of coupling electrical energy from one antenna to another is well known in the art and is used, for example, in car kits whereby the electrical energy to and from a handset antenna is coupled to and from a car antenna situated outside of the vehicle when the handset is positioned into a car kit holder inside the vehicle. 
     Still further, it should be appreciated that a similar suitable connection may be provided for connecting (e.g., via a coaxial cable) a car kit external antenna tuned to operate with signal frequencies in the satellite system bandwidth for satellite mode operation when the user is in a car. 
     It should thus now be appreciated that the handset  10  according to the present invention may be operated in one mode (cellular) without the burden of the large and heavy satellite mode antenna  26 . Given that the handset  10  will most frequently operate in that one mode (cellular), the user will be able to carry the handset  10  without that size and weight burden, potentially freeing the user to conveniently carry the handset  10  in his or her pocket (by freeing the design of the handset  10  from the constraint of size required for satellite mode antennas) and thereby increasing user acceptance and market appeal for such handsets  10  and the systems with which they work. 
     Only when the handset  10  is intended to be used in the satellite mode to communicate with the satellite system will the satellite mode antenna  26  necessarily be attached to the handset  10 . In that case, the antenna  26  can be readily and easily attached to the handset  10 , substituting itself for the cellular mode antenna  16  in the connection to the transceiver  56 , with operation thereafter occurring with an antenna  26  tuned for proper operation with signals in the satellite system bandwidth. 
     Still other aspects, objects, and advantages of the present invention can be obtained from a study of the specification, the drawings, and the appended claims. It should be understood, however, that the present invention could be used in alternate forms where less than all of the objects and advantages of the present invention and preferred embodiment as described above would be obtained.