Abstract:
A cradle for accepts a portable communications device (PCD) that is normally in radio communication with a first network. The cradle couples the accepted PCD to the first network by way of a second network when the PCD is out of radio communication with the first network. The PCD includes an externally accessible port from which communications data is accessible, and the cradle is sized to accept the PCD. The cradle has a port connector for coupling with the externally accessible port of the accepted PCD, a network connector for coupling the cradle and by extension the PCD to the second network, and a network communications device for interfacing between the port connector and the network connector.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present application is related to and filed concurrently with U.S. patent application Ser. No. 09/474,407, entitled “PORTABLE COMMUNICATIONS DEVICE COUPLABLE TO FIRST NETWORK BY WAY OF SECOND NETWORK”; U.S. patent application Ser. No. 09/474,406, entitled “EMULATING BASE STATION FOR COUPLING PORTABLE COMMUNICATIONS DEVICE TO FIRST NETWORK BY WAY OF SECOND NETWORK”; and U.S. patent application Ser. No. 09/473,604, entitled “METHOD OF COUPLING PORTABLE COMMUNICATIONS DEVICE TO FIRST NETWORK BY WAY OF SECOND NETWORK”, each of which is hereby incorporated by reference. 

   FIELD OF THE INVENTION 
   The present invention relates to a method and apparatus for extending coverage for a portable communications device such as an interactive (two-way) communications device. In particular, the present invention relates to extending coverage for a two-way pager in areas where the pager cannot transmit to a receiving station and/or receive from a transmitting station. 
   BACKGROUND OF THE INVENTION 
   Interactive two-way pagers and a pager network system in support thereof are known. Examples of such two-way pagers include the RESEARCH IN MOTION (RIM) “BLACKBERRY” two-way pager designed and/or marketed by RESEARCH IN MOTION Limited of Waterloo, Ontario, Canada and the MOTOROLA two-way pager designed and/or marketed by MOTOROLA Corporation of Schaumberg, Ill., USA. Such pagers typically include a battery compartment for receiving a battery, a processor, memory, a data screen for displaying alpha-numeric data, a micro-size keyboard for entering alpha-numeric data, a radio receiver for receiving data over air, and a radio transmitter for transmitting data over air. Accordingly, data may be transmitted from one pager and received by another by way of the network system. Likewise, data from a source external to the network system may be received by a pager, and such pager may transmit data to a destination external to the network system. In addition, such pagers typically include a serial port or the like by which data may be uploaded and/or downloaded, for example during pager initialization, set-up, and upgrade at a pager sales and/or service center. 
   Examples of pager network systems include the MOBITEX network designed and/or marketed by ERICSSON MOBILE COMMUNICATIONS AB of Sweden and the REFLEX network designed and/or marketed by MOTOROLA Corporation of Schaumberg, Ill., USA. Such network systems (“networks”) typically include one or more base stations, where each base station has associated with it a plurality of geographically spaced base transmitters, each of which can potentially transmit the data received by the radio receiver of the pager, and a plurality of geographically spaced base receivers, each of which can potentially receive the data transmitted by the radio transmitter of the pager. The base transmitters and the base receivers are spread out over a network coverage area, and each is assigned particular transmitting or receiving frequencies by its respective base station. 
   As should be appreciated, each base station is responsible for directing pager data to its ultimate destination or from its ultimate source. Such base station also assigns the frequencies to the base transmitters and base receivers, keeps track of the locations of pagers with respect to base transmitters and base receivers, assigns each pager to a particular base transmitter and to a particular base receiver as the pager is moved through the network coverage area, or at least through the portion thereof that the base station is responsible for, and transmits information to each pager regarding the assigned base transmitter and assigned base receiver and/or frequencies thereof, among other things. Since the pager must acknowledge receipt for data verification purposes and the like, among other things, the pager must always be in two-way communication with the network, even if only receiving data from such network. 
   Typically, the base transmitters operate at a relatively high power, owing to the fact that each pager is battery-operated and the receiver therein operates at a relatively low power. Also owing to the fact that each pager is battery-powered and the transmitter therein likewise operates at a relatively low power, the base receivers are typically concentrated at a higher number per geographical area than the transmitter base stations in the network coverage area. Accordingly, it is statistically more likely that a pager is closer to a base receiver than to a base transmitter. Correspondingly, it is also more likely that a pager in a fringe (i.e., area on the edge) or marginal (i.e., an area with poor transmission quality) portion of the network coverage area can receive data from a base transmitter, but that a base receiver cannot receive data from such pager, owing to the relatively low transmitting power of such pager. 
   The network coverage area for a pager network is typically finite. For example, such network coverage area may roughly correspond to a state or region, a portion of a state or region, a metropolitan area, a metropolitan area extending over portions of several states or regions, or the like. Accordingly, through cooperative service agreements between networks, ‘roaming’ pager coverage may be provided for a pager outside the network coverage area of its ‘home’ network. With such cooperative service agreements, the over-all pager coverage area encompasses a large portion of urban areas in the United States, and many rural areas too. Inevitably, though, there are significant portions of the United States where pager coverage is not available. As should be appreciated, coverage for a pager is not available anywhere the pager cannot communicate with both a base receiver and a base transmitter to achieve the aforementioned two-way communications link. For example, coverage is not available in fringe or marginal portions of the network coverage area or the over-all pager coverage areas (if roaming coverage is provided), as was pointed out above, and in areas external to the network coverage area or the over-all pager coverage areas (if roaming coverage is provided). This is true even if the pager can communicate with a base transmitter. Of course, coverage will also not be available anywhere the pager cannot communicate with a base transmitter, but for the reasons specified above, it is more likely that loss of communication with any base receiver will occur first, or at least concurrently. 
   Equally inevitably, individuals with two-way pagers or the like visit areas where coverage is not available, both in and out of the United States, and such individuals would like some sort of continued two-way paging service even though in such areas without coverage. Accordingly, a need exists for a method and apparatus to provide coverage for a two-way pager or the like, especially when the pager is outside the aforementioned coverage area. 
   SUMMARY OF THE INVENTION 
   In the present invention, a cradle accepts a portable communications device (PCD) such as a pager, where the PCD is normally in radio communication with a first network. The cradle couples the accepted PCD to the first network by way of a second network when the PCD is out of radio communication with the first network. The PCD includes an externally accessible port from which communications data is accessible, and the cradle is sized to accept the PCD and includes a port connector for coupling with the externally accessible port of the accepted PCD, a network connector for coupling the cradle and by extension the PCD to the second network, and a network communications device for interfacing between the port connector and the network connector. In a variation, the cradle is dispensed with and the PCD includes the network connector and network communications device. 
   To couple the PCD to the first network by way of the second network, the PCD is coupled to the second network, and is caused to leave a first network mode and enter a second network mode. The PCD then establishes a network connection with the first network by way of the second network, and enters into communication with the first network by way of the second network. 
   An emulating base station couples the PCD to the first network by way of the second network and includes a network connection for interfacing with the first network, a network communications device for interfacing with the second network, and a server coupled to the first network by the network connection and coupled to the second network by way of the network communications device. The server is programmed to emulate a radio base station. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing summary, as well as the following detailed description of preferred embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. As should be understood, however, the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings: 
       FIG. 1  is a block diagram showing a two-way pager or the like and a base station in accordance with one embodiment of the present invention; 
       FIG. 2  is a block diagram showing the two-way pager or the like and the base station of  FIG. 1  in accordance with another embodiment of the present invention; and 
       FIG. 3  is a flow chart depicting steps employed with the two-way pager and the base station of  FIGS. 1 and 2  in accordance with one embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Certain terminology may be used in the following description for convenience only and is not considered to be limiting. The words “left”, “right”, “upper”, and “lower” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” are further directions toward and away from, respectively, the geometric center of the referenced object. The words “vertical” and “horizontal” in the present application designate orientations with respect to an object when such object is positioned in a particular and/or customary manner, but do not restrict the present invention to the object in such position. The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import. 
   Referring now to  FIG. 1 , a pager  10  or the like and a base station  12  or the like are shown in accordance with one embodiment of the present invention. As was discussed above, and as shown, a typical two-way pager  10  is intended to be in communication with a pager network  13  and may include a battery compartment for receiving a battery  14 , a processor  16 , memory  18 , an output device such as a data screen  20  for displaying alpha-numeric data, an input device such as a micro-size keyboard  22  for entering alpha-numeric data, a radio receiver  24  for receiving data over air, and a radio transmitter  26  for transmitting data over air. Notably, any particular two-way pager  10  may be employed without departing from the spirit and scope of the present invention, and such pager  10  need not necessarily include all of the aforementioned elements  14 - 26 , again without departing from the spirit and scope of the present invention. For example, such pager  10  need not necessarily have the keyboard  22  or the data screen  20 , and could instead or in addition have a speaker and/or a microphone, a video and/or still camera and/or a video screen, and/or the like. 
   Importantly for purposes of the present invention, the pager  10  also includes an externally accessible serial port  28  or the like by which data may be uploaded and/or downloaded. As was discussed above, such serial port  28  has heretofore been employed for services such as pager initialization, set-up, and upgrade at a pager sales and/or service center. Nevertheless, the pager  10  is capable of interacting with a device in the field by way of such serial port  28 . 
   In one embodiment of the present invention, and as seen in  FIG. 1 , when the pager  10  is in an area where coverage is not available, such pager  10  may be placed in a cradle  30  or the like and thereby establish contact with the base station  12  by way of a network  32  such as a public switched (i.e., land line) telephone network, a mobile switching (i.e., mobile or cellular) network, an external computing network such as the Internet, an internal computing network, and the like. The public switched telephone network or the mobile switching network are most likely preferred due to their availability even in many remote and even wilderness locations. Such public switched telephone network or the mobile switching network may also be employed to dial into the aforementioned internal or external computing networks. 
   Preferably, the cradle  30  includes a serial port connector  34  for coupling with the serial port  28  of the pager  10 . As may be appreciated, the cradle  30  and the pager  10  may be constructed such that a positive connection between the serial port connector  34  and the serial port  28  is achieved merely by inserting such pager  10  into such cradle  30 . For example, the cradle  30  and the pager  10  may include keying features for guiding and aligning such pager  10  and such cradle  30  during coupling to achieve such positive connection. Such keying features (not shown) may include but are not limited to complementary grooves and ridges, protrusions and recesses, and the like. 
   Also preferably, the cradle  30  includes a network connector  36  or the like for coupling the cradle  30  and by extension the pager  10  to the network  32 . Of course, depending on the network  32 , the network connector  36  will vary. For example, for the public switched telephone network, the network connector  36  is merely a telephone connector that receives a connector on one end of a telephone cord, where the other end is appropriately coupled to such network. For the mobile switching network, the network connector  36  may be a port that couples via an appropriate cable to a corresponding port on a mobile phone which in turn is registered on such network. Alternatively, the functional components of such mobile phone are integrated within such network connector  36 . Other appropriate network connectors  36  may be employed based on the network  32  employed without departing from the spirit and scope of the present invention. 
   The cradle  30  further preferably includes a network communications device  38  for interfacing between the serial port connector  34  and the network connector  36 . Of course, depending on the network  32 , the network communications device  38  will vary. For example, for the public switched telephone network and the mobile switching network, the device  38  is an appropriately configured modem of a type that is typically employed for such purpose. For the internal or external computing network, the device  38  is an appropriately configured network interface such as a network interface card. Other appropriate network communications devices  38  may be employed based on the network  32  employed without departing from the spirit and scope of the present invention. In any instance, the device  38  receives data from the pager  10  by way of the serial port  28  thereof and sends such data to the network  32 , and also receives data from the network  32  and sends such data to the pager  10  by way of the serial port  28  thereof. 
   The cradle  30  may have its own power source, such as a battery or an AC power converter, and/or may derive its power from the received pager  10 . Of course, if power use is more than minimal, it may be preferable that the cradle  30  have its own power source so as not to excessively draw down the battery of such pager  10 . If the cradle  30  has its own power source, such cradle  30  may supply additional power to the pager  10  so as to conserve the battery of such pager  10  and/or provide a power boost to the pager  10 . 
   The base station  12  is a traditional base station in the sense that it performs all the normal base station functions with regard to directing data to and from the pager  10 . However, in one embodiment of the present invention, such base station  12  is a non-traditional base station in that it does not have any associated base transmitters or base receivers, and therefore need not concern itself with frequency assignment, pager tracking, pager assignment, and the like. Instead, such base station  12  is a dedicated base station solely for servicing pagers  10  through the network  32 . Accordingly, the base station  12  is coupled to and is a portal between the network  32  and the pager network  13  or the like. In such an instance, the base station  12  may include a server  40  coupled to the network  32  and to the pager network  13  and programmed to emulate all necessary two-way base station functions. Of course, to couple to the network  32 , the base station  12  may also have a network communications device  38  similar to the network communications device  38  in the cradle  30  (e.g., a modem). Moreover, to couple to multiple cradled pagers  10  by way of the network  32 , multiple network communications devices  38  may be employed if necessary. To couple to the pager network  13 , an appropriate network connection  42  may be employed. The details of the couplings, the connections, and the emulation are generally known and therefore need not be described herein in further detail. Of course, the base station  12  may in fact be a non-dedicated base station that directs data from both the network  32  and traditional base transmitters and base receivers without departing from the spirit and scope of the present invention. 
   In operation, and referring now to  FIG. 3 , when two-way operation of the pager  10  is disrupted because such pager  10  is out of range or is otherwise unable to contact its pager network  13 , the user thereof appropriately places such pager  10  into the cradle  30  (step  301 ) so that the serial port  28  of the pager  10  is coupled with the serial port connector  34  of the cradle  30 . In addition, such user appropriately couples the cradle  30  to the network  32  by way of the network connector  36  (step  303 ) and whatever appropriate coupling is necessary (a telephone cable, for example, in the case of a public switched telephone network). 
   Preferably, the pager  10  and the processor  16  therein are programmed to sense the connection to the cradle  30 , and thereby enter a ‘cradled’ mode (step  305 ) where the radio transmitter  26  and radio receiver  24  therein are not employed. Instead, in such ‘cradled’ mode, the pager  10  and the processor  16  therein preferably gain the attention of and establish control over the network communications device  38  (e.g., the modem) (step  307 ) within the cradle. Alternatively, the user may desire or be required to positively command the pager  10  to enter the cradled mode. Thereafter, the pager  10  and the processor  16  therein employ the network communications device  38  to establish a network connection with the base station  12  by way of the network  32  (step  309 ), and then the pager  10  and processor  16  therein enter into two-way communication with the base station  12  by way of the network  32  (step  31   1 ) to send and receive pager information. 
   Preferably, during the time when two-way operation of the pager  10  is disrupted because such pager  10  is out of range or is otherwise unable to contact its pager network  13 , and before the pager  10  enters into two-way communication with the base station  12 , any outgoing data from the pager  10  (such as outgoing messages and other outgoing information) is held in the memory  18  of the pager, and any incoming data destined for the pager  10  (such as incoming messages and other incoming information) is held in an appropriate memory location of the pager network  13 . Accordingly, upon establishing two-way communication between the pager  10  and the base station  12  by way of the network  32 , such incoming and outgoing data is released and exchanged therebetween. Moreover, upon establishing two-way communication between the pager  10  and the pager network  13  byway of the base station  12  and the network  32 , additional incoming and outgoing data (such as new messages and other information) may be composed and exchanged therebetween. 
   When the user wishes to end the session, such user may command the pager  10  to do so (step  313 ). The pager may also automatically end the session after a pre-determined period of in-activity, among other things. The user can then remove the pager  10  from the cradle  30  (step  315 ) and de-couple the cradle  30  from the network  32  by way of the network connector  36  (step  317 ). Preferably, upon sensing removal from the cradle  30 , the pager  10  returns to a ‘normal’ mode. Alternatively, the user positively commands the pager  10  to return to normal mode. In one embodiment of the present invention, the user can leave the pager  10  in the cradle  30  and allow the pager  10  to automatically make a connection to the base station  12  by way of the network  32  on a periodic or predetermined basis. 
   Even if coverage is available for the pager  10  in the normal mode by way of the pager network  13 , such pager  10  may still be placed in cradled mode to establish two-way communication between the pager  10  and the base station  12  by way of the network  32  without departing from the spirit and scope of the present invention. Reasons for doing so may include anticipation of more reliable two-way communication, and availability of higher data transmission speeds, among other things, as well as user choice or preference. 
   In a variation on the embodiment of the present invention shown in  FIG. 1 , the actual structure of the cradle  30  is dispensed with, and the pager  10  or the like is coupled directly to the network communications device  38 . Such direct coupling may for example be achieved by way of a serial port connector  34  at the end of a cable which is appropriately attached to such network communications device  38 . 
   In another embodiment of the present invention, and referring now to  FIG. 2 , the cradle  30  of  FIG. 1  is omitted, but the necessary contents and/or functionality therein are re-located to the pager  10 ′, as is shown. Thus, the serial port connector  34  of  FIG. 1  is no longer necessary, as the network communications device  38  and the connection between such network communications device  38  and the serial port  28  of the pager  10 ′ are internal to such pager  10 ′. The network communications device  38  (e.g., a modem) may thus comprise a chip set within the pager  10 ′, or the processor  16  of the pager  10 ′ may be programmed with the functionality of such device  38 . The network connector  36  is still necessary but is now mounted directly to the pager  10 ′ by appropriate means. Preferably, the network connector  36  is a micro-size connector to conserve space, and may for example be of a type that ‘flips out’ from the pager  10 ′ in a known manner. 
   In operation, the non-cradled pager  10 ′ of  FIG. 2  by definition cannot automatically sense a connection to any cradle  30 . Accordingly, such pager  10 ′ must be positively commanded to enter ‘cradled’ mode, or must automatically sense a connection to the network connector  36  to enter ‘cradled’ mode. Likewise, such pager  10 ′ must be positively commanded to enter ‘normal’ mode, or must automatically sense a disconnection from the network connector  36  to enter ‘normal’ mode. Otherwise, the steps shown in  FIG. 3  are performed in substantially the same manner. 
   Of course, the present invention also encompasses the use of two-way networked data communications devices and portable communications devices other than the pager  10 . Similarly, the present invention encompasses the use of one-way pagers  10  and other similar devices. Likewise, the data from and to the pager  10  or the like may be directed by devices other than a base station  12 , emulated or otherwise. 
   The programming necessary to effectuate the present invention, such as the programming run by the processor  16  of the pager  10  and the programming run by the server  40  of the base station, is known or is readily apparent to the relevant public. Accordingly, further details as to the specifics of such programming is not believed to be necessary herein. 
   As should now be understood, in the present invention, a method and apparatus are provided to support coverage for a two-way pager or the like, especially when the pager is outside the coverage area of its pager network. Changes could be made to the embodiments described above without departing from the broad inventive concepts thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.