Patent Publication Number: US-6223029-B1

Title: Combined mobile telephone and remote control terminal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application hereby incorporates by reference the following co-assigned patent applications which describe related subject matter in greater detail: U.S. patent application Ser. No. 08/476,504, entitled “MODULAR UNIT HEADSET,” filed Jun. 7, 1995 (Docket No. 27946-00098; inventors: Nils Rutger Rydbeck and Per Stein); U.S. patent application Ser. NO. 08/471,606, entitled “ELECTRONIC EQUIPMENT AUDIO SYSTEM,” filed Jun. 6, 1995 (Docket No. 27946-00085); U.S. patent application Ser. No. 08/577,086, entitled “IDENTIFICATION OF MOBILE CALLS WITHIN A MOBILE TELEPHONE SYSTEM,” filed Dec. 22, 1995 (Docket No. 27943-00033; inventor: Eric Valentine); and U.S. patent application Ser. No. 08/353,966, entitled “MODULAR RADIO COMMUNICATIONS SYSTEM,” filed Dec. 12, 1994 (Docket No. 27946-00070; inventor: Per Stein). This application is a continuation-in-part of U.S. application Ser. No. 08/616,054, entitled “AN INTEGRATED LOCAL COMMUNICATION SYSTEM,” filed Mar. 14, 1996, now U.S. Pat. No. 5,913,163, and U.S. application Ser. No. 08/712,570, entitled “CIRCUIT ASSEMBLY FOR EFFECTUATING COMMUNICATION BETWEEN A FIRST AND A SECOND LOCALLY-POSITIONED COMMUNICATION DEVICE”, filed Sep. 11, 1996, now U.S. Pat. No. 5,983,100. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention relates to communication systems and, more particularly, to a mobile phone providing both mobile telephony and remote control functions. 
     2. Description of Related Art 
     Recent advances in wireless telecommunications have been multifaceted, resulting in a myriad of new products and services. In the mobile cellular telecommunications area, some of the new services include both private services usually provided within a home or business environment for private mobile subscribers and public services provided through a public land mobile network for public mobile subscribers. Both private and public mobile service may be provided on a cellular basis, with mobile subscribers being allowed to roam between the geographic coverage areas of different base stations of each of the private and public systems. 
     Private mobile service is typically provided through a private mobile telephony network that is implemented using a private cordless system standard such as the Cordless Telephone Standard 2 (CT-2). Private telephony systems may be provided as standalone networks or connected to a fixed telephony network. 
     Public mobile service is, on the other hand, generally provided through a cellular telecommunications network using one of the common cellular transmission standards such as the Advanced Mobile Phone Service (AMPS) System Standard, or the Global System for Mobile Communication (GSM) Standard. 
     Another direction in which there have been related developments is the area of cordless telephony products. Cordless telephone communications systems that are connected to a public switching telephone system (PSTN) have been known for some time. Cordless telephones operate utilizing a portable telephone unit in communication with a base station through a pair of radio frequency (RF) transceivers in the portable unit and in the base station. When the device is operable and a call is placed, dial tone and voice signals are transmitted from the RF transmitter in the portable unit to the RF receiver in the base station, and then over the PSTN lines in the ordinary manner. Similarly, when a call is received, the voice signals are transmitted from the RF transmitter in the base station to the RF receiver in the portable unit. 
     Although cordless telephones are convenient in that they allow telephone communication without the impaired-mobility imposed by a cord, they still require, like conventional corded telephones, usage of at least one hand to hold the portable unit for operating. Recent attempts that address the limitations of conventional cordless telephones have resulted in headset-like portable units that allow hands-free operation. In U.S. Pat. No. 4,882,745 to Silver, a “cordless headset telephone” is described in which only a single earphone is included to cover one ear while leaving the other ear open. Another related device is disclosed in U.S. Pat. No. 4,741,030 to Wilson, wherein a cordless headset is provided with a dial board positioned near the microphone for easy viewing by the user. As in the Silver device, the Wilson device does not disclose the use of two earphones and a volume control to enhance sound quality and to block external ambient noise. Another cordless telephone headset using only a single earphone is disclosed in U.S. Pat. No. 4,484,029 to Kennedy. 
     A recent improvement over these above-mentioned cordless telephone headsets is described in U.S. Pat. No. 5,113,428, wherein the portable unit is totally contained in a headset having its own push button key pad, related control buttons, a rechargeable battery, an RF transceiver and two earphones with volume control. 
     A co-assigned pending U.S. Patent Application, entitled “MODULAR UNIT HEADSET,” cross-referenced hereinabove and incorporated by reference herein, describes an integrated system wherein a host electronic system, coupled to a PSTN, is capable of communicating with a headset by both wireless and wired means due to a modular unit attached to it. In yet another co-assigned pending U.S. Patent Application, entitled “ELECTRONIC EQUIPMENT AUDIO SYSTEM,” cross-referenced hereinabove and incorporated by reference herein, describes a module port having a module connector, that is capable of communicating with a microphone via wireless and wired means. 
     It is readily apparent that a logical progression of these multifaceted advances is towards increased inter-operability and modularized integration of multiple physical devices so as to enhance human operator convenience. For example, it would be an advantage to have a mobile station equipped with a modular unit that is capable of communicating with a cordless phone base station so that it can operate as an extension of the cordless phone to effectuate landline communication. It would be of further advantage to have a wireless headset that is capable of communicating on a single protocol with both the mobile station and cordless phone base station. In such a system, the human operator has the benefit of hands-free operation of multiple telecommunications devices without having to interchange different modular units. 
     Additionally, it can be readily appreciated that it would be of significant advantage to inter-operably integrate an electronic data terminal into such a local area communication system (LACS) whereby the utility of the terminal is further maximized. It is apparent that such an electronic data terminal can be a computer, which in turn may be standalone or in a Local Area Network, or a telefax, a pager, a printer, or a hand-held data organizer. Further, integrating a conventional phone answering machine that is operable to play back an out-going greeting or a recorded caller message and to record an incoming message, into the LACS will undoubtedly enhance operator convenience and the use of the device. The method and apparatus of the present invention and various components thereof provide such advantages. 
     Additional benefit could be realized by providing the mobile station with dual functionalities such that it is able to provide normal telephony functions and act as a remote control unit for a variety of peripheral devices accessible through some type of local area communication system or related communication system. In this manner, an individual may utilize the multifunction mobile telephone to perform a variety of functionalities. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the foregoing and other problems with a mobile telephone station providing combined mobile telephony and remote control terminal functionalities. The mobile station include a transceiver portion that provide normal mobile telephony functionalities enabling a user to interact with a Public Land Mobile Network. One or more peripheral devices are associated with the mobile station and are remotely actuable in response to a set of predetermined control commands. A control command module within the mobile station generates the variety of predetermined control commands to which the peripheral devices are responsive. The control commands are transmitted to the peripheral device via a wireless communication link that is set up between the peripheral device and the control command module. The mobile station may alternatively only include means for generating and communicating the control command to the peripheral devices without the transceiver providing mobile telephony functionality. Also, the mobile station may consist of a hands-free headset. 
     The control command module may further include one of or both of a speech recognition module enabling user control of the peripheral devices via spoken voice command or a DTMF recognition module enabling user control with the peripheral devices via DTMF entries. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the method and apparatus of the present invention may be had by reference to the following detailed description when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is a block diagram of the broad network interconnection of an integrated local area communication system comprising a plurality of communication devices; 
     FIG. 2 is a block diagram of an integrated local communication system in accordance with a presently preferred exemplary embodiment of the present invention; 
     FIG. 3 is a block diagram of the implementation of a local area communication system in accordance with an aspect of a presently preferred exemplary embodiment of the present invention; 
     FIG. 4 is a block diagram of an implementation of a mobile station providing mobile telephony and remote control functionalities within a local area communications system; 
     FIG. 5 is a block diagram of an implementation of a mobile station providing both mobile telephony and remote control functionalities within a communications system using the mobile station as a master controller; 
     FIG. 6 is a block diagram of a mobile station providing mobile telephony and remote control functionality within a first local area communication system and within a secured communications system using the mobile station as a master controller; 
     FIG. 7 is a block diagram of the system of FIG. 5 wherein a hands-free headset is substituted for the mobile station; 
     FIG. 8 illustrates a network interconnection of multiple Public Land Mobile Networks (PLMNs) to a Public Switching Telephone Network (PSTN); 
     FIG. 9 is a block diagram of a PLMN; 
     FIG. 10 is a block diagram of a conventional land-line telephone unit; 
     FIG. 11 is a block diagram of a conventional cordless phone base unit; 
     FIG. 12 illustrates a block diagram of a conventional wireless headset unit; 
     FIG. 13A depicts a block diagram of a presently preferred embodiment of a local interface module adapted for use with a mobile station in accordance with the present invention; 
     FIG. 13B is a block diagram of a presently preferred embodiment of a home base station or directly-connectable local interface module adapted for use with a PSTN in accordance with the present invention; 
     FIG. 13C is a block diagram of a presently preferred embodiment of a local interface module adapted for use with a serial computer port connector in accordance with the present invention; 
     FIG. 13D is a block diagram of a presently preferred embodiment of a local interface module adapted for use with an electronic data terminal in accordance with the present invention; 
     FIG. 13E is a block diagram of a presently preferred embodiment of a local interface module adapted for use with a cordless phone base unit associated with a PSTN in accordance with the present invention; 
     FIG. 13F is a block diagram of a presently preferred embodiment of a local interface module adapted for use with a peripheral device which may be remotely controlled by a mobile station in accordance with the present invention; 
     FIG. 14 shows an exemplary decision tree that may be used in accordance with the present invention to selectably effectuate local wireless communication for in-coming calls; and 
     FIG.  15 A and FIG. 15B show an exemplary decision tree that may be used in accordance with the present invention to selectably effectuate local wireless communication for call initiation. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     FIG. 1 depicts the broad network interconnection of an integrated local area communication system (LACS) according to the present invention, generally denoted by reference numeral  100 . The local communication system  100  envisions seamless integration of a plurality of electronic communications devices,  110 - 1  through  110 -N, at least one of which may be connected to an external communication network, shown herein by reference numerals  140 - 1  through  140 - 4 . The connections,  130 - 1  through  130 - 4 , between the plurality of devices  110 - 1  through  110 - 4  and the external communications systems  140 - 1  through  140 - 4 , may be wireless or wire-line, according to the present invention. 
     Still referring to FIG. 1, a plurality of local interface modules,  120 - 1  through  120 -N, are shown as connected to the plurality of devices  110 - 1  through  110 -N. According to a presently preferred exemplary embodiment of the present invention, each of the plurality of local interface modules  120 - 1  through  120 -N is capable of effectuating wireless communication with the other N- 1  local interface modules. According to the present invention, the local communication can be voice, video and data, or any combination thereof. Further, the local communication is effectuated upon a single communication protocol involving a local medium which can be electro-magnetic waves such as radio, infra-red, optic spectra or microwaves, or magnetic waves, or wire-line. The local signal may be analog or digital, with any suitable modulation known in the art. 
     FIG. 2 illustrates a block diagram of a presently preferred exemplary embodiment of the present invention, generally denoted by reference numeral  200 . Reference numeral  210  refers to a radio-enhanced phone interfacing device, coupled to a public switching telephone network (PSTN)  260 . In one aspect of the invention, the radio-enhanced phone interfacing device  210  can be simply a known cordless phone base unit capable of short-range wireless communication in a home or office environment. 
     Continuing with FIG. 2, reference numeral  240  refers to a known mobile station associated with a Public Land Mobile Network (PLMN)  270 . Reference numeral  230  refers to an electronic data terminal, as referenced and described hereinabove, that may be associated with a local area network (LAN)  280 . It will be understood by the persons of ordinary skill in the art upon reference hereto that there are many known variations and modifications of the electronic data terminal  230 . For instance, it can be a computer that is selectably associated within a distributed computing environment. Alternatively, it can also be a printer, or a telefax machine, or a pager, or a phone answering machine, or a hand-held data organizer or any other electrical, electronic or mechanical device. It is within the spirit of the present invention that these known variations and modifications of the electronic data terminal  230  are capable of being arranged in a local communication network in accordance with the present invention. 
     Still referring to FIG. 2, reference numeral  220  refers to a wireless headset, provided in a presently preferred exemplary embodiment to maximize user convenience in effectuating a local communication path. Reference numerals  250 - 1  through  250 - 4  refer to four local interface modules. The local interface module  250 - 1  is coupled to the radio-enhanced phone interfacing device  210 , the local interface module  250 - 2  is coupled to the wireless headset  220 , the local interface module  250 - 3  is coupled to the electronic data terminal  230  and the local interface module  250 - 4  is coupled to the mobile station  240 . It will be appreciated by the persons of ordinary skill in the art that although the local interface modules  250 - 1  through  250 - 4  are shown as separate functional blocks, they are capable of being integrated structurally into their respective communication devices  210 ,  220 ,  230  and  240 . Furthermore, the radio-enhanced phone interfacing device  210  may be such that its associated local interface module  250 - 1  is functionally integrated into its native circuitry as well. Similarly, the wireless headset  220  and the local interface module  250 - 2  can be, in one aspect of the invention, functionally integrated also. 
     Referring now to FIG. 3, therein is shown an implementation of a local area communication system in accordance with an aspect of a presently preferred exemplary embodiment of the present invention. Reference numeral  210  is the radio-enhanced phone interfacing device that is associated with the PSTN  260  for external land-line communication. Reference numeral  261  is the associative path between the PSTN  260  and the radio-enhanced phone interfacing device  210 . The communication signals on this path  261  may be analog or digital, and further, it may in a specific embodiment be a T 1  phone line, or an Integrated Services Digital Network (ISDN) connection, or a high-capacity Asymmetric Digital Subscriber Line (ADSL). The radio-enhanced phone interfacing device  210 , which is shown to have a local antenna  211  for local communication, may be a cordless phone base unit coupled with a corresponding local interface module (not shown) or a directly-connectable home base station. 
     The mobile station  240  is associated with the PLMN  270  for cellular communication. The cellular path  271  may be effectuated between the mobile station  240  and the PLMN  270  using any one of the common cellular transmission standards such as the Advanced Mobile station Service (AMPS) System standard or the Global System for Mobile Communication (GSM) Standard. The mobile station  240  is equipped with a non-local antenna  242  to facilitate transmission and reception of cellular communication signals between the mobile station  240  and a base station (not shown) . In addition, the mobile station  240  is coupled to a local interface module  241  having a local antenna  243  for local communication. The coupling between the mobile station  240  and the local interface module  241  is such that the non-local cellular communication signals over the cellular path  271  are selectably convertible to local communication signals, and vice versa, to be transmitted on a local communication link as will be discussed hereinbelow. The local interface modules  241  also enable communications between peripheral devices  210 ,  220 . 
     The wireless headset  220  is operable either as a wireless extension to the mobile station  240  via a first local radio communication link  310  or as a hands-free phone unit for communication over the PSTN  260  via a second local radio communication link  320 . A third local radio communication link  330  is selectably established between the mobile station  240  and the radio-enhanced phone interfacing device  210  whereby the mobile station  240  is selectably operable as a hands-on phone unit associated with the radio-enhanced phone interfacing device  210  to place a call over the PSTN  260 . 
     Referring now to FIG. 4, there is illustrated an implementation of a mobile station  2000  providing both mobile telephony and remote control functions via the local area communications system. A radio enhanced phone interface device  2005  which interfaces with the mobile station  2000 , such as a home base station, enables communication between the mobile station  2000  and the PSTN for external landline communication. The mobile station  2000  includes a communications link  2010  enabling communication with an associated Public Land Mobile Network (PLMN)  2020  for cellular communications via mobile telephony functions module  2015 . The cellular communications link  2010  may be effectuated between the mobile station  2000  and the PLMN  2020  using any one of the common cellular transmission standards, such as the Advanced Mobile Phone Service (AMPS) system or the Global System for Mobile Communications (GSM). 
     The mobile station  2000  also includes a command control module  2025  and local communications module  2027  for local control and communications with a plurality of associated local interface modules  2035  associated with various peripheral devices  2040 . The command control module  2025  generates instructions for controlling the peripheral devices  2040  in response to user input. The local communications module  2027  forms a local communications link  2045  between the mobile station  2000  and peripheral devices  2040  through local interface modules  2035 . The local interface modules  2035  are coupled to the command control module  2025  of the mobile station  2000  via a local communication link  2045  using a communication protocol involving a local medium involving electromagnetic waves such as radio, infrared, optic spectra microwaves, or magnetic waves. The local communications link  2045  may be analog or digital, with any suitable modulation known in the art. The local interface modules  2035  are associated with a variety of peripheral devices  2040  including, but not limited to, a hands-free headset, television, radio, stereo, VCR (video player), personal computer, printer/plotter, home base station, answering machine, light, dimmer switch, thermostat, door, alarm, vibrator, car alarm, car-lock mechanism, garage door, personal alarm, watch phone, refrigerator or freezer. Using the local communications link  2045  each of these devices may be controlled from the mobile station  2000 . 
     In some situations, the remote control and mobile telephony functionalities may work in concert such as with the personal security alarm. A user equipped with a peripheral device  2040  comprising a personal alarm associated with a mobile station  2000  via a local communications link  2045  may actuate a button on the alarm device that transmits a signal to the mobile station via the communications link. This signal causes the mobile station  2000  to automatically contact a prestored number or transmit an SMS message to a preselected party via the PLMN communications link  2010 . The user could then communicate with a party at the prestored number using the hand-held mobile station  2000  or a hands-free headset. 
     In an additional example, a mobile station  2000  and wireless vibrator may work in concert to notify a user of a call to the mobile station  2000 . When a mobile station is initially turned on, an identification code is transmitted to the vibrator. After this initialization, the vibrator will actuate upon detection of a ring signal from a mobile station  2000  transmitting the correct ID code. This enables a user to carry only the vibrator rather than an entire mobile station  2000  within a local area and separates the vibrating unit from sensitive electronics of the mobile station. 
     A user enters control commands through a user interface  2050  of the mobile station  2000 . The control commands are processed by the command control module  2025  and transmitted to an associated local peripheral device  2040  via the communications link  2045 . In one embodiment, the user interface  2050  (and/or the command control module  2025 ) has associated with it a voice recognition module  2055  enabling user control of the various peripheral devices  2040  through spoken commands. Control of the peripheral devices  2040  may also be effectuated via a dual tone multifrequency (DTMF) recognition module  2060  responsive to DTMF commands keyed in by a user. Additional command formats may also be used to control the peripheral device through some types of command module. Alternatively, the user interface  2050  may include means for initiating commands through the use of buttons, a touch screen, joystick or other type of mechanical controller useful for handicap individuals. 
     Referring now to FIG. 5, there is illustrated an alternative implementation of the multifunction mobile station  2000  of the present invention wherein the mobile station is not implemented within a local area communication system. Instead, the mobile station  2000  comprises a master controller of a local communications network. All signals of the local communications link  2045  are controlled through the local communications module  2027 . The mobile station  2000  is able to communicate with a PSTN network, PLMN network and a variety of peripheral devices  2040  via local interface modules  2035  associated with each of these items. Each peripheral device  2040  can communicate directly with the mobile station  2000  via an associated communications link  2045  between the command control module  2025  and the local interface modules  2035  of the peripheral devices. Communications between the peripheral devices  2040  and the PLMN and the PSTN respective, via the local interface module  2035  are not possible in this configuration. All communications must pass through the local communications module  2027  of the mobile station  2000 , (i.e., the local interface modules  2035  cannot communicate with each other). The types of peripheral devices  2040  controlled and the manner of control using this configuration are the same as those discussed with respect to FIG.  4 . 
     Referring now to FIG. 6, there is illustrated yet another alternative implementation of the multifunction mobile station  2000  of the present invention wherein the mobile station is implemented within a local area communications system and as a master controller of a local communication network. In this situation, in a first area  2067  all signals of a local communications network are controlled through the local communications module  2027  in the mobile station  2000 . The mobile station  2000  is a master controller of the local interface modules  2035  and the peripheral devices  2040  may not communicate with each other in the first area. In a second area  2068 , within local area communications system, each of the local interface modules  2035  may communicate with each other and with the mobile station  2000 . This enables intercommunication among all the peripheral device  2040  and the mobile station  2000 . The types of peripheral devices  2040  controlled and the manner of control using this configuration are the same as those discussed with respect to FIGS. 4 and 5. 
     Furthermore, as shown in FIG. 7, the hand-held mobile station  2000  may be substituted with a hands-free headset  2000   a . The headset  2000   a  would include a command control module  2025  and local communications module  2027  providing a communications link  2045  with the local interface modules  2035  of the peripheral devices  2040  and/or a home base station attached to a PSTN network. The headset  2000   a  may or may not include a further communications link  2010  with a public land mobile network  2020 . Control of the various peripheral devices  2040 , such as those discussed previously with respect to FIG. 3, would occur via the local communications link  2045  between the hands-free headset  2000   a  and peripheral devices  2040 . 
     Referring now to FIG. 8, reference numeral  410  generally illustrates a possible network interconnection of multiple PLMNs  270 A,  270 B to PSTN  260 , according to an aspect of the presently preferred exemplary embodiment of the present invention. A mobile subscriber (MS)  420  is associated with one of the PLMNs as its Home PLMN  270 A. Within each PLMN  270 A,  270 B, there are multiple mobile switching centers (MSCs)  470 A,  470 B, servicing the geographical areas covered by the network. The mobile subscriber  420  who is served by its Home PLMN  270 A is capable of communicating with other wireless and wire-line terminals by connecting with the PSTN  260  through a Gateway Mobile Switching Center (GMSC)  430 A. An access tandem (AT)  440  associated within the PSTN  260  routes the mobile calls generated from the PLMN  270 A to wire-line terminals serviced by one of its exchanges within the PSTN  260 , or to another PLMN  270 B by way of its GMSC  430 B. If the mobile subscriber  420  travels outside the coverage area of its Home PLMN  270 A and roams into the geographical area covered by an adjacent PLMN  270 B, an interexchange handoff occurs between the Home PLMN  270 A and the adjacent PLMN  270 B whereby telecommunications service continues to be provided to the MS  420  from the adjacent PLMN  270 B as a roaming subscriber. 
     FIG. 9 is a block diagram of the PLMN  270  including the mobile switching center  470 . In addition, the PLMN  270  comprises a Home Location Register (HLR)  480 , a Visitor Location Register (VLR)  490  and a number of antenna systems  500 - 1  through  500 -M. The mobile switching center  470  is also generally known in the art as a base station system, and includes a base-station controller  510  and one or more of base-station transceiver stations(BS)  520 - 1  through  520 -L. Each of the base-station transceiver stations is associated with a subgroup of the antenna systems  500 - 1  through  500 -M. In order for the mobile subscriber  420  to be allocated to a home network, an entry in the HLR  480  is made. Whenever the MS  420  is switched on, and possibly at regular intervals thereafter, it will register with the PLMN  270  and give its location area. 
     The MSC  470  communicates directly with the HLR  480  and the VLR  490  for subscriber information and transfers calls from one BS to another as the MS  420  travels within the geographical area covered by the PLMN  270 . Further, the GMSC  430  acts as a gateway to allow access to other wire-line terminals associated with the PSTN  260  or wireless mobile subscribers associated with other PLMNs. 
     The establishment of a cellular call within and without the PLMN  270  is typically effectuated via Signaling System No.  7  (SS 7 ) network protocols utilizing network addresses. A co-assigned pending U.S. Patent Application, “IDENTIFICATION OF MOBILE CALLS WITHIN A MOBILE TELEPHONE SYSTEM,” filed Dec. 22, 1995, cross-referenced hereinabove and incorporated by reference herein, describes a method and system for utilizing network addresses to construct a unique call identifier for a cellular call. 
     Referring now to FIG. 10, a block diagram of a conventional landline telephone is shown generally at  610 . This telephone  610  consists of a cradle  635  and a handset  645 . The telephone  610  is connected to the PSTN  260  by a wire-line connection  615  which carry analog or digital telephone signals. It can be readily appreciated that the wire-line connection  615  can be substantially identical to the associative path  261  shown in FIG.  3  and described hereinabove. The cradle  635  includes Data Access Arrangement (DAA) section  620 , key pad  625 , and ringer circuit  630 . On the other hand, the handset  645  includes speaker  640  and microphone  650 . The DAA  620  contains analog filters and other known protection devices required to connect to the PSTN  260 . The key pad  625  is used to provide the number to be called to the PSTN  260 . Ringer circuit  630  and known associated signaling means are provided to inform the user when there is an incoming call. 
     FIG. 11 illustrates a block diagram of a conventional cordless phone base unit, generally shown at  710 , which can be operable, for instance, at frequencies close to or within the 46 MHZ to 49 MHZ frequency range. The cordless phone base unit  710 , conceptually, is a subminiature cellular system providing at least a signaling channel which transmits outbound signals in a fashion similar to a conventional cellular outbound signaling channel, and receives service requests from a remote hand-held unit  715 . 
     The base unit  710  has a local PSTN line interface  720 , a remote unit interface  730  coupled to an antenna  770 , a channel switch  740 , a tone signal source  750  generating tone signals such as a ringing tone signal, and a controller  760 . The channel switch  740  selectively makes a channel between the local PSTN line interface  720  and the remote unit interface  730 , and a channel between the tone signal source  750  and the remote unit interface  730 . It is known in the art that the local PSTN line interface  720  may comprise a hook circuit (not shown) performing an open/close control of a loop, a call detection circuit (not shown) for detecting a call signal and a sender (not shown) for sending dialing push-button signals. It is also well known in the art that the remote unit interface  730  comprises a voice-band processing circuit (not shown), a mixer (not shown), a radio transceiver (not shown) coupled to the antenna  770 . The controller  760  controls the local PSTN line interface  720 , the channel switch  740 , and the remote unit interface  730 . 
     Referring now to FIG. 12, reference numeral  810  generally shows a block diagram of a wireless headset according to an aspect of the present invention. An antenna  820 , operable to receive and transmit local communication signals which may be effectuated using either standard wireless communication protocols or a proprietary protocol, is electrically connected to a radio transceiver  830 . As is well known in the art, the functionality of the radio transceiver  830  may be implemented in numerous known ways, with attendant electronic circuitry for tuning etc. 
     Continuing with FIG. 12, the signal output from the radio transceiver  830  is then fed into a baseband modulator/demodulator block  840  which either extracts the information signal from the local carrier radio wave or modulates the local carrier radio wave using the information signal. The in-coming information signal is then fed into a speaker  880  via a driver/amplifier block  850 . It is well known in the art that the speaker  880  and the driver/amplifier block  850 , in physical implementation, may take a variety of known forms. The out-going information signal is generated by a microphone  870  which is amplified by the driver/amplifier block  850 . The amplified out-going information signal is then modulated with a local carrier radio wave for local transmission over a local medium. A controller block  860  is preferably provided which is in circuit communication with the radio transceiver  830 , the baseband modulator/demodulator  840  and the driver/amplifier  850 , in order to supervise the bidirectional transfer of the information signals. In one aspect of the present invention, the controller block  860  may comprise a microprocessor, a plurality of control switches, memory and/or hardwired digital logic. In yet another aspect of the present invention, the implementation of the wireless headset may include a single housing with its own push button key pad and related control buttons, and a portable power source such as a rechargeable battery. In an additional aspect, the wireless headset may include two earphones, a swing-out microphone, flexibly mounted to the housing, a volume control for enhanced realistic binaural sound, and a supplementary head strap for securing the unit to the user&#39;s head. Further, the antenna  820  may preferably be disposed within the swing-out arm provided for the microphone  870 , although in still another aspect of the invention, it may be coupled to one of the earphones such that it is extendable from the housing of the earphone. Moreover, in lieu of a conventional on/off switch, there may preferably be provided a voice-activated mechanism to facilitate connection/disconnection of a local communication link with the headset. Additionally, the earphones may preferably be formed of a resilient rubber or plastic material to securely engage the user&#39;s ear and minimize the reception of external background noise. Alternatively, the earphones may be cupped cushions for foam cushions similar to high fidelity earphones in order to further reduce ambient background noise. Furthermore, it should be understood upon reference hereto that the aesthetic aspects of the wireless headset may in turn give rise to certain design features as well. 
     FIG. 13A is a block diagram of a presently preferred exemplary embodiment of a local interface module adapted for use with the mobile station  240  (not shown) that is associated with the PLMN  270  (not shown). FIG. 13B is a block diagram of a presently preferred exemplary embodiment of a local interface module adapted as a directly-connectable home base station associated with the PSTN  260 . FIG. 13C is a block diagram of a presently preferred exemplary embodiment of a local interface module adapted for use with a serial computer port connector. FIG. 13D is a block diagram of a presently preferred exemplary embodiment of a local interface module adapted for use with the electronic data terminal  230 . FIG. 13E is a block diagram of a presently preferred exemplary embodiment of a local interface module adapted for use with the cordless phone base unit  210  associated with the PSTN  260 . 
     Referring now specifically to the local interface modules,  905 -A to  905 -F of FIGS. 13A to  13 F, respectively, it can be readily appreciated that according to a presently preferred exemplary embodiment of the present invention, the local interface modules are substantially identical to one another, and to a great extent, are similar to the wireless headset, shown in FIG.  12 . As described hereinabove, the antenna  820  is operable to receive and transmit local communication signals which may be effectuated using either standard wireless communication protocols or a proprietary protocol, on a single local communication medium which can be an electro-magnetic wave, an infra-red wave, a radio wave, a microwave, a magnetic wave, an optic wave or even a wire-line connection. The modulation and demodulation of the communication signal is achieved by the baseband modulator/demodulator  830  which is coupled to an interface circuitry block,  910 -A through  910 -F. The interface circuitry block  910 -A effectuates appropriate conversion of communication signals between the local interface module  905 -A and a system connector  920  coupled to the mobile station  240  (not shown). The interface circuitry block  910 -B effectuates appropriate conversion of communication signals between the directly-connectable local interface module  905 -B (or, home base station, as has been described hereinabove) and the PSTN  260 . The interface circuitry block  910 -C effectuates appropriate conversion of communication signals between the local interface module  905 -C and a serial port connector  930 . In one aspect of the present invention, the serial port connector  930  may preferably be an RS- 232  type connector. Alternatively, the interface circuitry block  910 -C may be of PCMCIA-Standard-compatible, as described in a co-assigned pending U.S. patent application, Ser. No. 08/353,966, cross-referenced hereinabove and incorporated by reference herein. The interface circuitry block  910 -D effectuates appropriate conversion of communication signals between the local interface module  905 -D and the electronic data terminal  935 . The interface circuitry block  910 -E effectuates appropriate conversion of communication signals between the local interface module  905 -E and the cordless phone base unit  210  that is associated with the PSTN  260 . 
     According to a presently preferred embodiment of the present invention, each of the local interface modules  905 -A to  905 -F may preferably be disposed within the housing of the communication device (not shown) with which it is to interface. Alternatively, the local interface module may also be disposed in a separate housing such that it forms a plugable unit to be received in a module port in the communication device. As mentioned hereinabove, the controller module  860  in FIGS. 12A to  12 F is substantially similar to the controller module  860  in FIG.  11 . 
     FIGS. 14,  15 A and  15 B show two flowcharts illustrating an exemplary decision tree that may be used according to the teachings of the present invention in order to effectuate local wireless communication among at least a radio-enhanced phone interface device, a mobile station and a wireless headset. Since maximization of user convenience and flexibility is a desired object of the present invention, different decision trees may be employed to suit different conditions of operation. 
     Referring now specifically to FIG. 14, therein is shown a flowchart for selectably effectuating local wireless communication links for call reception. Steps  1005  and  1020  are decision blocks to determine if the incoming call is a PSTN call or if it is a cellular call over the PLMN. If the call is a PSTN call, then the user needs to determine if the mobile station or the headset is to be used to function as the call terminating device. This step is provided in the decision block  1010 . If the mobile station is present within the geographic area of coverage provided for the radio transceiver unit of the local interface module attached to the radio-enhanced phone interface device and the user selects to use the mobile station to receive the PSTN call, the user takes the MS path  1011 . Upon making that determination, the user can selectably establish a wireless local communication link between the mobile station and the radio-enhanced phone interface device as shown at  1015 . On the other hand, if the mobile station is out of range for use with the radio-enhanced phone interface device, or if the user desires to use the wireless headset to receive the incoming PSTN call, the user takes the Headset path  1013  to selectably establish in step  1017  a local wireless communication link between the wireless headset and the radio-enhanced phone interface device. Further, if the wireless headset is out of range, or if the user does not desire to use the wireless headset, then the user may proceed as in step  1016  to receive the PSTN call by using the conventional wireless, or corded, handset by taking the path shown at  1012 . 
     If the incoming call is a cellular call, as determined by step  1020 , then the user has a choice of using the mobile station in a conventional manner to receive that call, shown in step  1035 , or establish a wireless local communication link between the mobile station and the wireless headset, provided they are within a suitable range from each other, as shown in step  1040 . 
     Referring now to FIGS. 15A and 15B, therein is shown an exemplary decision tree for initiating a call according to the teachings of an aspect of the present invention. Decision blocks  1105  and  1125  are employed to determine whether the outgoing call is to be transmitted over the PLMN or the PSTN. If the outgoing call is a PSTN call, the user takes the YES path shown at  1104 . After this step, the user has the choice of call initiation by using a wireless headset with keypads, or by using a mobile station as shown in the decision block  1110 . If the user desires to use the mobile station and if the mobile station is within the local range of the radio-enhanced phone interface device, the user may by taking the MS path  1113  selectably establish the local communication link between the mobile station and the radio-enhanced phone interface device as shown in  1121 . If the user desires, on the other hand, to use the headset by taking the Headset path  1111 , subsequent steps of the decision tree are dependent on whether the wireless headset is equipped with its own key pad necessary for remote operation. This condition is tested in the decision block  1115 . If the determination is NO, the user takes the path  1116  to initiate the PSTN call using the key pads associated with the radio-enhanced phone interfacing device as shown in step  1117 . Afterwards, the user can return via path  1118  to using the wireless headset as in step  1119  which is also reached if the user takes the YES path  1114  from the decision block  1115 . Alternatively, if neither the mobile station nor the wireless headset is selected by the user, then call initiation over the PSTN will proceed by using a conventional handset, if provided with the radio-enhanced phone interface device, shown in step  1120 . 
     Similarly, if the outgoing call is a cellular call as determined in  1125 , the user then has the choice of using either the headset, or the mobile station. If either the headset is not in a suitable range, or if the headset is not equipped with a key pad, then the user initiates the cellular call using the mobile station as shown in step  1165  which is reached via either  1141  or  1136 . After initiating the cellular call using the mobile station, the user has the option of returning to using the headset via a return path  1172 , or continue using the mobile station as shown in  1175 . Also, by taking the YES step  1142  from the decision block  1140 , the user may selectably establish a local communication link between the headset and the mobile station as shown in  1160 . 
     Although presently preferred exemplary embodiments of the method and apparatus of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the invention as set forth and defined by the following claims. For example, it will be readily appreciated that the local communication paths may also comprise infra-red (IR) or microwave or magnetic wave links and the corresponding receivers/transmitters will be used in lieu of radio transceivers. Additionally, the term “radio transceiver” as used herein comprises appropriate radio control logic of the type necessary to constitute a radio device that is capable of communicating using a wireless communication standard such as DAMPS, GSM, DECT, etc. The transceiver may include, in addition to a transmitter and receiver, data modem circuitry, when the communications device is used for data transmission. Further, both local and non-local (that is, disposed between the plurality of communications devices and their respective external communications networks) communications signals may be analog or digital, and may comprise voice, video and data. Accordingly, it will be readily appreciated by the persons of ordinary skill in the art upon reference hereto that the exemplary modifications and substitutions mentioned hereinabove do not depart from the spirit of the present invention, directed to a local area communication system (LACS) capable of effectuating a local communication path among a plurality of communications devices using a single local communication medium.