US20090075602A1 - Communication systems and method - Google Patents

Abstract

Users can make landline, wireless and/or internet calls from a conventional landline communication device. If the communication device is on a wireless call, that call may be placed on hold to answer an incoming call on the landline. Likewise, if the communication device is on a landline call, that call may be placed on hold to answer an incoming call on the wireless telephone. Wireless and landline calls may also be conferenced together.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application is a divisional of application Ser. No. 10/359,277, filed Feb. 6, 2003, which claims the benefit under 35 U.S.C. Section 119(e) of provisional Application No. 60/394,283, filed Jul. 9, 2002. The contents of each of these application are incorporated herein in their entirety.
BACKGROUND AND SUMMARY OF THE INVENTION
• This application generally relates to communication systems and methods and, more particularly, to such systems and methods in which communication devices for the conventional Public Switched Telephone Network (PSTN) may be interfaced with other communication networks such as wireless communication networks and the Internet.
• The use of cellular telephones has dramatically increased, resulting in many individuals having at least two different telephones: a conventional landline telephone for home use and a cellular telephone for use away from home or for business. Cellular service providers (CSPs) now offer low-cost calling plans to attract new customers and retain current customers. Eventually, CSPs are likely to offer calling plans (e.g., unlimited nationwide calling) at rates that cause users to consider whether they have any need to subscribe to local telephone companies for telephone services.
• Despite the fact that many cellular phone users can make unlimited long distance calls on nights and weekends, it is still an underused feature. In some cases, the under-usage is because many cellular phone users are unable to receive a signal strong enough to make cellular phone calls from their homes. In addition, cellular phones are not designed to maintain long conversations (e.g., greater than 30-minutes) due to over-heating. The ergonomic design and limited battery life of cellular phones further discourages their prolonged use.
• In one example embodiment of the communication systems and methods described herein, users can make wireless telephone calls from a conventional landline communication device connected via interface circuitry to a single ring tip line pair. The communication device may be any communication device that is ordinarily configured for communication over a landline such as a telephone, a computer system, a set-top box, a personal video recording device, etc. The interface circuitry is also connected to a wireless communication device. Among other things, the interface circuitry permits both landline calls and wireless calls to be placed and received using the landline communication device. Other communication devices connected to the same landline may be used to place and receive landline calls even if the landline communication device is being used to place or receive a wireless call. The interface circuitry is configured so that if the landline communication device is on a wireless call, that call may be placed on hold to answer an incoming landline call. Likewise, if the landline communication device is on a landline call, that call may be placed on hold to answer an incoming wireless call. Landline and wireless calls may also be conference together. In one example embodiment, the system may be provided with a very sensitive and powerful wireless transceiver that permits the capture and transmission of wireless signals. Although such a transceiver is not required, such a feature if provided extends the communication range of the wireless communication device that is connected thereto.
• In an illustrative implementation, upon receipt of an incoming wireless call, the interface circuitry automatically and distinctively rings the landline communication device connected thereto. If the landline communication device is answered, the interface circuitry establishes an audio path between the wireless communication device and the landline communication device. If the user wishes to place a wireless call using the landline communication device, the user picks up the telephone, dials the number of the called party, and then enters a predetermined wireless call code. The interface circuitry provides the number to the wireless communication device, which then dials the number (bypassing the local telephone company). To place a landline call, the user enters a predetermined landline call code that is recognized by the interface circuitry. The communication device is connected to the PSTN and the call may then be placed through the PSTN.
• The system can provide wireless connectivity to personal computers, facsimile machines, printers and other computer and electronic devices. Such wireless connectivity allows the system to take advantage of third generation (3G) cellular networks and systems. For example, if the system received video information or text data, the information can be sent to a television screen, computer monitor, printer, facsimile machine and the like.
• In accordance with another example embodiment of the communication systems and methods described herein, a communication system includes a caller ID (CID)-enabled landline communication device and interface circuitry connected to a ring-tip line pair and to a wireless communication device. The interface circuitry includes a memory and a processing circuit for transferring data from the wireless communication device to the memory, selectively reading out the contents of the memory in response to inputs from a user requesting display of the contents, and transferring the read-out memory contents to the communication device using a CID protocol. In one illustrative implementation, the read-out data comprises names and telephone numbers. In this case, the inputs from the user may be used to dial a displayed number and/or read out a next or previous name and telephone number. The inputs from the user may also be used to access names beginning with certain letters.
• These and other features and advantages provided by the invention will be better and more completely understood by referring to the following detailed description of presently preferred embodiments in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a generalized block diagram of anexample communication system100;
• FIG. 2A is a circuit block diagram of one example ofinterface circuitry106;
• FIG. 2B is a detailed schematic showing the interconnections of the various switches in theexample interface circuitry106 shown inFIG. 2A;
• FIG. 3 is a table summarizing the states of the switches in theexample interface circuitry106 shown inFIG. 2A for various functions and operations;
• FIG. 4 is a perspective view of a example arrangement for practically implementing the system discussed with respect toFIG. 1;
• FIGS. 5A-5L are flowcharts showing various example routines for theinterface circuitry106;FIG. 5A is a flowchart showing an illustrative Main Loop;FIG. 5B is a flowchart showing an illustrative Off-Hook routine;FIG. 5C is a flowchart showing an illustrative Incoming Cell Call routine;FIG. 5D is a flowchart showing an illustrative Incoming Landline Call routine;FIG. 5E is a flowchart showing an illustrative Outgoing Call routine;FIG. 5F is a flowchart showing an illustrative Phone On-Hook Routine;FIG. 5G is a flowchart showing an illustrative Outgoing Landline Call routine;FIG. 5H is a flowchart showing an illustrative Flash Button Pressed routine;FIG. 5I is a flowchart showing an illustrative Outgoing Cell Call routine;FIG. 5J is a flowchart showing an illustrative Incoming Calls Check routine;FIG. 5K is a flowchart showing an illustrative Call Waiting routine; andFIG. 5L is a flowchart showing an illustrative Ten Second Timer routine;
• FIG. 6 is a functional block diagram of an example implementation of interface circuitry;
• FIGS. 7A-7F are flowcharts illustrating example operations involving the interface circuitry shown inFIG. 6;FIG. 7A shows example operations that occur when the telephone goes into the off-hook state;FIG. 7B shows example operations that occur at the end of all calls;FIG. 7C shows example operations that occur when a cell call is received while the user is on a landline call;FIGS. 7D and 7E show example operations that occur when a landline call is received while the user is on a cell call; andFIG. 7F shows example operations that occur when there is an incoming call;
• FIG. 8 is a circuit block diagram of another example ofinterface circuitry106; and
• FIG. 9 shows components involved in making an internet call.
DETAILED DESCRIPTION
• FIG. 1 is a generalized block diagram of anexample communication system100.Communication system100 includes acommunication device102 connected viainterface circuitry106 to a ring-tip line pair104 for landline calls over thePSTN105. As is well-known,PSTN105 includes a hierarchy of telephony switching offices. For example, individual subscribers are connected to a nearby telephone exchange, sometimes referred to as an end office or switching office; the switching office is connected to a local central office; the local central office is connected to a toll office; the toll office is connected to a primary telephony center; and the primary telephony center is connected to a sectional telephony center. Sectional telephony centers are connected to regional telephony centers, which typically are the highest level in thePSTN105 switching hierarchy.Other communication devices110 may also be connected toline pair104. Thecommunication devices102,110 may be any communication devices that are configured for communication overPSTN105 such as telephones, computer systems, facsimile machines, set-top boxes, personal video recording devices, etc.
• Interface circuitry106 is also connected to awireless communication device108 for awireless communication network107.Wireless communication network107 may be for any conventional wireless service such as analog advanced mobile phone service (AMPS), digital advanced mobile phone service (D-AMPS), global system for mobile communications (GSM), personal communication service (PCS), satellite service (including low earth-orbiting satellites), specialized mobile radio (SMR), and cellular digital packet data (CDPD). A cellular communication network, for example, is made up of cells, each of which includes at least radio transmitter/receiver with which a cellular communication device can communicate. Under the control of a switching office, the radio transmitter/receiver with which the cellular communication device communicates changes as the cellular communication device moves from one cell to another. Example cellular communication devices include cellular telephones and cellular personal digital assistants (PDAs). In the following description,communication devices102 and108 are sometimes referred to as telephones. However, use of the term “telephone” in a particular instance is not intended to exclude the possibility of using other communication devices.
• Among other things,interface circuitry106 permits both landline calls viaPSTN105 and wireless calls viawireless communication network107 to be placed and received usingcommunication device102. Theother communication devices110 connected to thesame landline104 ascommunication device102 may be used for landline calls even ifcommunication device102 is being used to place or receive a wireless call because, during a wireless call,communication device102 is physically disconnected fromlandline104 and is connected to thewireless communication device108 viainterface circuitry106. As will be discussed in greater detail below, the interface circuitry is configured so that ifcommunication device102 is engaged in a wireless call, that wireless call may be placed on hold to answer an incoming landline call viaPSTN105. Likewise, if thecommunication device102 is engaged in a landline call, that landline call may be placed on hold to answer an incoming wireless call viawireless communication network107. Wireless and landline calls can also be conferenced together.
• Communication system100 may also includeother devices109 connected to interfacecircuitry106. For example, such devices may be output devices for outputting information received via the wireless communication system. These devices may include a television, a monitor, a facsimile machine, a printer and the like.
• To make a call overPSTN105 fromcommunication device102, a user first inputs a predetermined code (e.g., “#”) to the communication device. For example, if the communication device is a telephone, the user may press certain buttons on the keypad of the telephone. Among other things, this code results ininterface circuitry106 connectingcommunication device102 toline pair104. Thereafter, the user can simply dial the number of the called party. To make a call over the wireless communication network fromcommunication device102, the user simply dials the number of the called party and enters a predetermined code (e.g., “#”) when dialing is finished. When the predetermined code is entered at the end of the called party's number,interface circuitry106 provides the dialed number to the wireless communication device which then dials the number to place the call.
• As an alternative or in addition to determining how to place a call based on the inputting of predetermined codes, the interface circuitry may automatically determine whether to place a call fromcommunication device102 viaPSTN105 orwireless communication network107. For example, if one of theother communication devices110 is already on a landline call,interface circuitry106 may detect this condition and automatically place any call fromcommunication device102 overwireless communication network107 usingwireless communication device108.Interface circuitry106 may also determine whether to place a particular call fromcommunication device102 overPSTN105 or overwireless communication network107. This determination may, by way of illustration, be based on cost. For example, some monthly cellular telephone plans provide for low cost long-distance calls at certain times such as evenings and weekends. Ifwireless communication device108 is a cellular telephone connected to a cellular telephone network,interface circuitry106 may therefore be configured with intelligence (e.g., real time clock to determine time that a call is placed, a memory storing calling rates, etc.) to place long distance calls fromcommunication device102 over the cellular communication network via the cellular telephone at these times.
• FIG. 2A is a circuit block diagram of one example ofinterface circuitry106. InFIG. 2A,wireless communication device108 is a cellular device andwireless network107 is a cellular network. It will of course be appreciated that the following description is applicable to any of the wireless devices and services mentioned above.Line pair104 provides DC current (e.g., to power electronics of the communication device102), AC current to ring the telephone bell, and a full duplex communication path. Ahold circuit11 is selectively connected via ahold switch12 across the tip-ring pair to place a call on hold without disconnecting the call. Holdcircuit11 may, for example, comprise a 350-ohm resistor.Communication device102 is connected toline pair104 via first andsecond switches30,32.
• The interface circuitry also includes a ringing Subscriber Line Interface Circuit (SLIC)20 that performs a variety of functions. RingingSLIC20 detects and decodes Dual Tone Multi-Frequency (DTMF) codes generated bycommunication device102 and communicates these codes to Digital Signal Processor (DSP)22. RingingSLIC20 creates and generates standard and custom telephone signals and tones such as busy signals, dial tones, and the like, and also rings thecommunication device102 when there is an incoming call fromPSTN105 orcellular communication network107. Specifically,DAA36 detects incoming calls vialine pair104 and provides an incoming landline call signal toDSP22. In response to this signal,DSP22causes ringing SLIC20 to ringcommunication device102. Similarly,DSP22 detects incoming calls tocellular communication device108 via its connection thereto overbus48. In response to this detection,DSP22causes ringing SLIC20 to ringcommunication device102. RingingSLIC20 may provide different rings to distinguish between incoming cellular and landline calls. RingingSLIC20 also generates analog signals used, for example, to send information such as CID (Caller ID) data tocommunication device102. In addition, becausecommunication device102 is only selectively connected toline pair104, an integrated DC-DC converter of ringingSLIC20 is used to power the communication device. Thus, for example, if the communication device is a telephone, a user is able to press buttons on the telephone even though the telephone is not connected to thelandline104. This is desirable because during a cellular call, the telephone needs an external power supply. As noted above, such power is provided byline pair104 during a landline call. RingingSLIC20 also performs on-hook and off-hook detection and generates on-hook and off-hook detection signals that are provided toDSP22 in response to these detections. On-hook refers to the state in which the communication device is not being used such as when a telephone handset is placed on the cradle. Off-hook is the state when the communication device is in use such as when a telephone handset is removed from the cradle, releasing the hook switch. RingingSLIC20 performs serial communication by sending data over abus44 toDSP22 using a standard communication protocol such as 4-wire Serial Peripheral Interface (SPI) protocol.Bus44 is used to send status information (on-hook, off-hook, ringing, etc) toDSP22, andDSP22 usesbus44 to send commands and retrieve information from ringingSLIC20.
• DSP22 is the central processor ofinterface circuitry106 and controls all the functions thereof. For example,DSP22 is connected viabus48 to the external data connector of thecellular communication device108.DSP22 can control the functions of the cellular telephone (e.g., dialing, answering incoming calls, ending calls, power on/off, etc.) via commands sent overbus48. Software is programmed intoDSP22 and/or is accessible frommemory42 to implement the various functions described herein. While a DSP is used as a control circuit in the example embodiment, it will be appreciated that various other types of control circuits including microprocessors, microcontrollers, logic circuits, application specific integrated circuits (ASICs), programmable array logic, etc. and combinations thereof may be used to implement some or all of the functions described herein.
• DAA36 is an analog interface toline pair104 whose primary function is to monitor the voltage/current ofline pair104 and to detect incoming landline calls.DAA36 is connected toDSP22 via a bi-directionalserial communication line46 and communicates withDSP22 when certain events occur such as an incoming landline call.DAA36 detects incoming CID information, functions as a data modem, and may be provided with protocol stacks for applications such as internet access (e.g., dial-up) and voice-over-IP. The DAA has analog-to-digital converters for converting the analog audio signal fromline pair104 to a digital stream that is sent toDSP22 and digital-to-analog converters for converting digital audio fromDSP22 to analog audio signals that are output to linepair104.DAA36 complies with the telephone standard of many countries. 2-to-4-wire (hybrid)converter40 is a line interface provided betweencommunication device102 andcellular communication device108 for, among other things, providing line impedance matching and 2-to-4 wire conversion.Converter40permits communication device102 to send/receive audio to/fromcellular communication device108.
• The example interface circuitry shown inFIG. 2A includes various switches to connect/disconnect elements from each other. These switches are controlled byDSP22. For ease of illustration, the connections betweenDSP22 and the switches are not shown inFIG. 2A. Although these switches are shown inFIG. 2A as hardware switches, the switching may in fact be implemented in software as discussed in detail below with reference toFIG. 8.First switch30 is used to disconnectcommunication device102 fromline pair104 to reduce the possibility of the user hearing noise if the user is on a cellular call and there is an incoming landline call, or if someone is on another extension in the home or office.First switch30 is used in conjunction withthird switch34 to allow calls to be placed fromcommunication device102 either viaPSTN105 orcellular communication network107.Second switch32 is used to selectively connect/disconnect DAA36 toline pair104. This arrangement allowsDAA36 to monitor all activity of line pair104 (i.e., incoming calls, line voltages, etc).Second switch32 is used in conjunction withhold switch12 to place a landline call on hold without disconnecting it.Third switch34 is used to disconnectcommunication device102 from ringingSLIC20 during a landline call. This avoids damage to ringingSLIC20 when thecommunication device102 is being used in landline mode (e.g., placing or receiving a landline call). Holdswitch12 selectively connects a 350-ohm resister ofhold circuit11 across theline pair104 and permits a call to be placed on hold without the call being disconnected by the local phone company. Finally,audio switch38 switches the audio path betweencellular communication device108 andcommunication device102 on and off.Audio switch38 allows the system to place a cellular call on hold, while the user answers a landline call during a call-waiting situation. If desired,audio switch38 may be omitted and a mute function ofconverter40 may be used to perform functions similar to those ofaudio switch38.
• To make a call overPSTN105, the user first placescommunication device102 in the off-hook state. RingingSLIC20 detects this off-hook state and sends an off-hook signal toDSP22. In response to the off-hook signal,DSP22 closessecond switch32 andthird switch34, and opensfirst switch30,audio switch38 and holdswitch12. The user then presses the # button. RingingSLIC20 detects this button press and sends the # button press code toDSP22. In response to the # button press code,DSP22 connectscommunication device102 toline pair104 by controlling the various switches so that first andsecond switches30,32 are closed andthird switch34, holdswitch12 andaudio switch38 are open. The user then dials a telephone number to place a call overPSTN105. If the called party answers, communication such as conversation may begin. If the called party does not answer, the calling party hangs up andcommunication device102 is then in an on-hook state.
• To make a call overcellular communication network107 viacellular communication device108, the user again placescommunication device102 in the off-hook state. RingingSLIC20 detects this off-hook state and sends an off-hook signal toDSP22. In response to the off-hook signal,DSP22 closes second andthird switches32,34 and opensfirst switch30,audio switch38 and holdswitch12. The user then dials the desired telephone number, which is detected and decoded by ringingSLIC20 and forwarded toDSP22. When the user presses “#” after entering the telephone number,DSP22 closesaudio switch38 and then communicates the telephone number overbus48 tocellular communication device108, which thereafter dials the number.DSP22 may, for example, use RS232 protocol at 9600 baud to communicate overbus48 with the cellular telephone, although other protocols may readily be utilized. Becauseaudio switch38 is closed, an audio path is provided betweencellular communication device108 andcommunication device102. If the called party answers, communication such as conversation may begin. If the called party does not answer, the calling party hangs up andcommunication device102 is then in an on-hook state. RingingSLIC20 detects the on-hook state and sends an on-hook signal toDSP22.DSP22 thereafter ends the cellular call and disconnectscommunication device102 fromcellular communication device108 by openingaudio switch38.
• In the above-described implementation, the interface circuitry connects thecommunication device102 for a PSTN call in response to the input of a predetermined code before the user enters a telephone number and connects the communication device for a wireless network call in response to the input of a predetermined code after the user enters a telephone number. Of course, it will be readily appreciated that the interface circuitry may be configured to connect the communication device for a wireless call in response to the input of a predetermined code before the user enters a telephone number and to connect the communication device for a PSTN call in response to the input of a predetermined code after the user enters a telephone number.
• FIG. 2B is a detailed schematic showing the interconnections of the various switches in theexample interface circuitry106 shown inFIG. 2A. As discussed above,DSP22 controls the switches in order to perform various functions and operations. A first switch configuration is used when placing or receiving a call viaPSTN105. In this configuration, first and second switches30A,30B,32A,32B are closed and third switch34A,34B; hold switch12A,12B; and audio switch38A,38B are open. In this first switch configuration,communication device102 is connected via closed first andsecond switches30,32 toline pair104.Audio switch38 is open to disconnectcommunication device102 from thecellular communication device108. Becausecommunication device102 receives power fromline pair104,third switch34 is also open. A second switch configuration is used when placing or receiving a call viacellular communication network107. In this second configuration, first switch30A,30B and hold switch12A,12B are open. Second and third switches32A,32B,34A,34B and the audio switch38A,38B are closed. Closing switch32A,32B allowsDAA36 to detect incoming calls viaPSTN105 when thecommunication device102 is being used for a cellular call. A third switch configuration is for the on-hook state (i.e., whencommunication device102 is not being used to place or receive a landline or a cellular call). In this third configuration, first switch30A,30B; hold switch12A,12B; and audio switch38A,38B are open. Second and third switches32A,32B,34A,34B are closed.
• To place a landline call on hold and connect to a cellular call, switch12A,12B is closed and the second switch configuration is then utilized. To place a cellular call on hold and connect to an incoming landline call, the first switch configuration is utilized. Thus, the user has call waiting between landline and cellular calls and the user can press the flash button on their phone to activate this feature (i.e., place the landline call on hold, and answer incoming cellular call or vice versa) when they hear the special call waiting tone. If the user does not subscribe to call waiting, there is a possibility that during a call waiting event (e.g., the user is on a landline call, and there is an incoming cellular call), when the user presses the flash button, the local telephone company will see this flash event and disconnect the landline call. This is because when the flash button is pressed the telephone goes in the on-hook state for 300-700 ms and then goes back into the off-hook state. In short, if the user does not subscribe to a call waiting service, the phone company may disconnect the landline call when the flash button is pressed. To circumvent this problem, the flash button is re-mapped to another button on the telephone such as the “*’ button. In this case, during a call waiting event (as described above) the user presses the “*” button instead of the flash button on his/her telephone. The telephone company will know that the “*” button is pressed, but this press will be ignored. On the other hand, because the interface circuitry can detect an incoming call, when it detects that the “*” button is pressed during a call waiting event, the system places the landline call on hold, and connects the user to the cellular call. This flash functionality can also be provided using a dedicated flash button. Call conferencing between cellular and landline calls may be accomplished in response to an appropriate user input by closingaudio switch38 and placing the other switches in the same configuration as for a landline call (i.e., the first switch configuration described above).
• FIG. 3 is a table summarizing the states of the switches in theexample interface circuitry106 shown inFIG. 2A for various representative functions and operations.
• FIG. 4 is a perspective view of an example arrangement for practically implementing the system discussed with respect toFIG. 1. While this example arrangement shows the system components provided in an integrated manner, the invention is not limited in this respect. For example, the interface circuitry may be physically separate from the communication device and connected between the line pair and the communication device. The arrangement shown inFIG. 4 includes atelephone handset202 received in acradle203 of abase unit204.Base unit204 is connected (not shown) to line pair104 (seeFIG. 2A) and to a power outlet (not shown).Handset202 andbase unit204 are configured for cordlesscommunication using antennas205 and206 as is well known in the art. The handset includes amicrophone207, aspeaker208, and akeypad209 that can be used, for example, to place and receive calls.Keypad209 includes numeric keys 1-9, a “*” key, a “#” key and three function keys. The function keys may include a flash button, a mute button, a hold button, an answering machine button, and the like.Handset202 may also include adisplay210 such as a liquid crystal display. Various arrangements ofkeypad209 anddisplay210 may be used and the invention is not limited in this respect.
• Base unit204 includes aspeaker211, amicrophone212 and akeypad213 that can be used, for example, to place and receive calls without using the handset.Base unit204 also includes acradle214 withconnector215, which includes electrical contacts for electrically connecting the base unit to the data connector of acellular telephone220. Because the electrical connectors of cellular telephones typically differ from manufacturer to manufacturer (and even within models from the same manufacturer),FIG. 4 showscellular telephone220 connected tobase unit204 via anadapter217 that “adapts” the electrical connector configuration of the cellular phone to the electrical connector configuration ofbase unit204. Of course, it will be readily apparent that the systems and methods described herein are not in any way limited to an arrangement in which an adapter is required to connect the cellular telephone to the base unit. For example, different base units may be provided with electrical connectors that are specific to a particular manufacturer or even a particular model. In this case, the cellular telephone may be directly inserted intocradle214. Of course, the advantage of an adapter is that a single base unit with a universal electrical connector may be used, provided adapters are used that “adapt” the particular electrical connector configuration of different cellular telephones to the universal connector configuration of the base unit.
• Interface circuitry106 is incorporated withinbase unit204. The interface circuitry may include RF circuitry (not shown) for improving the range of thecellular telephone220, for example, by boosting the power of the transmitted cellular signals and by improving the cellular signal levels that can be detected using anantenna218. This RF circuitry may be connected to the cellular telephone via the cellular telephone's external antenna connector (not shown).
• As explained above,interface circuitry106, among other things, permits both landline calls and cellular calls to be placed and received using thehandset202. To place a wireless call, the user takes thehandset202 off-hook, enters the telephone number of the called party, and enters “#” (or some other code) after entering the telephone number. If desired, the cellular signals are communicated via the aforementioned RF circuitry. If the called party answers, audio is communicated between the user and the called party via an audio path within the interface circuitry. To place a PSTN call, the user first enters “#” (or some other code). The interface circuitry recognizes this code as indicating that the user wishes to place a PSTN call. The switches within the interface circuitry are then controlled so thathandset202 is connected toline pair104 and the user can then dial the number of a called party and place the call over the PSTN.
• BecauseDSP22 is typically configured (or may be easily configured) with the appropriate protocol stacks for Internet access, the user of the systems and methods described herein has the ability of making three types of calls whencommunication device102 goes off-hook: landline, wireless and internet (IP). The called party does not have to have the system described herein to receive such calls. In what follows, the user is assumed to have a dialup connection, although other connections such as broadband connections can also be used.
• With reference toFIG. 9, ISP's typically have local servers/voice gateways802 located in major cities throughout the United States and other countries.Interface circuitry106 connects to anISP804 over alandline806 of the PSTN. The user's voice is digitized by the ringingSLIC20, packetized byDSP22, and communication is established over theinternet808 with a local server/voice gateway802 that corresponds to the area code and local exchange of the called party. The local server then places a local call to the called party's number over the PSTN and, if the called party answers, a communication link is thereby established between theinterface circuitry106 and the called party. The voice gateway converts digital audio from the server and injects it onto the telephone line to the called party. The voice gateway converts analog audio from the called party to digital data, encapsulates it and communicates it to the server, which in turn, forwards the data to the interface circuitry over the internet.Interface circuitry106 converts the digital data to an analog signal, which can be heard by the calling party.
• More specifically, to place a voice-over-IP (VOIP) call, the user lifts handset, and presses a predetermined internet call code, which places the interface circuitry into an IP call mode. Under the control ofDSP22,DAA36 dials and connects to the user's ISP. When this connection is established, the user is provided with a confirmation tone, which indicates that a call may now be placed. The user then dials the number he/she wishes to call (e.g., 410-555-5555). Wheninterface circuitry106 detects the DTMF button presses, it decodes the area code (in this case, the area code for Maryland) and decodes the local exchange “555” which will be assumed to be for Columbia, Md. Then,interface circuitry106 sends signal viaISP804 to a local server/voice gateway that is located in that local exchange (i.e., Columbia, Md.). When communication is established with the local server/voice gateway, an instruction is sent which instructs the local server to dial the following number of the called party (i.e., 410-555-5555). The voice (PSTN) gateway of the local server places the call to called party's number. When the call is answered, the gateway acts as the interface between the PSTN call and the IP call. Incoming internet calls to interfacecircuitry106 would be the same as receiving a normal landline call because the call would be placed by a local server/voice gateway.
• DSP22 ofinterface circuitry106 executes software stored in internal memory and/or in an external memory accessible thereto (such as memory42). This memory may be read-only memory, read/write memory or some combination thereof and may be volatile and/or non-volatile. Generally speaking, the operations described below may be implemented in hardware, firmware and/or software. In the example embodiment ofinterface circuitry106 shown inFIG. 2A, the operations are implemented using software. The data and instructions for this software are stored in a storage medium such asmemory42 that is accessible toDSP22.DSP22 executes these instructions in response to various signals supplied thereto such as on-hook signals, off-signals, and the like. For purposes of theFIG. 5 discussion below,communication device102 is a telephone. However, as noted above, the invention is not limited in this respect.
• FIGS. 5A-5L are flowcharts showing various example routines for theinterface circuitry106. The program including these routines may be implemented, for example, using an event-driven state machine. After an event is handled, the state machine enters a “do-nothing” state until another event occurs. At the end of a routine, control generally returns to the calling routine. For example, if routine A calls routine B, control returns to routine A when routine B ends.
• FIG. 5A is a flowchart showing an illustrative Main Loop. At ST,1150, a check is made for incoming landline and cell calls. AtST1151, a check of hook switch status is made and at ST1152 a check is made for DTMF keypresses. The routine then returns toST1150.
• FIG. 5B is a flowchart showing an illustrative Off-Hook routine. This routine is initiated whencommunication device102 goes into the off-hook state. For example, the off-hook state may precede the placing or answering of a call or going to a call on hold. The off-hook state is detected by ringingSLIC20, which provides an off-hook signal toDSP22. In response to the off-hook signal,DSP22 executes the Off-Hook routine. AtST1001, the routine determines whether there is an incoming cell call. If so, the Incoming Cell Call routine (seeFIG. 5C) is entered atST1002. If not, the routine proceeds toST1003 where a determination is made as to whether there is an incoming landline call. If there is an incoming landline call, the Incoming Landline Call routine (seeFIG. 5D) is entered atST1004. If there is no incoming landline call, the routine continues toST1005 where a determination is made as to whether the user is on a call. If the user is not on a call, the Outgoing Call routine (seeFIG. 5E) is entered atST1007. If the user is on a call, the routine determines atST1006 whether a touchtone button is pressed. If no touchtone button is pressed, the Off-Hook routine ends. If a determination is made atST1006 that a touchtone button has been pressed, the routine determines atST1008 whether the flash button is pressed. If the flash button has been pressed, the Flash Button Pressed routine (seeFIG. 5H) is entered atST1009. If not, the Off-Hook routine ends.
• FIG. 5C is a flowchart showing an illustrative Incoming Cell Call routine. This routine is accessed, for example, from the Off-Hook routine ofFIG. 5B (i.e., the user has picked up the telephone) when a determination is made that there is an incoming cell call. AtST1010, the ringing oftelephone102 generated in response to the incoming cell call is stopped. An answer call command is sent to cellular telephone108 (ST1011) and an on cell-call flag is set (ST1012). Thereafter, the routine ends.
• FIG. 5D is a flowchart showing an illustrative Incoming Landline Call routine. This routine is accessed, for example, from the Off-Hook routine ofFIG. 5B (i.e., the user has picked up the telephone) when a determination is made that there is an incoming landline call. AtST1020, the ringing oftelephone102 generated in response to the incoming landline call is stopped. Next, atST1021,third switch34 and theaudio switch38 are opened, andfirst switch30 is closed. An on landline call flag is then set atST1022. Thereafter, the routine ends.
• FIG. 5E is a flowchart showing an illustrative Outgoing Call routine. This routine is accessed, for example, from the Off-Hook routine ofFIG. 5B (i.e., the user has picked up the telephone) when determinations are made that there is no incoming landline or cellular call and that the user is not currently on a call. AtST1030, second andthird switches32,34 are closed andfirst switch30,audio switch38 and holdswitch12 are opened. A determination is made at ST1031 (which is also the entry point of the DTMF button press check routine) as to whether the phone on-hook flag is set. If so, the routine proceeds toST1032 where the Phone On-Hook (seeFIG. 5F) routine is carried out. If not, a determination is made atST1033 as to whether a touchtone button has been pressed. If no touchtone button has been pressed, the routine ends. If a touchtone button has been pressed, the routine proceeds toST1034 where a determination is made as to whether a predetermined key has been pressed. For purposes of the discussion herein, the predetermined key will be the “#” key, although the invention is not limited in this respect. If the “#” key has not been pressed, the routine continues toST1035 where the key that was pressed is stored in memory. The routine then ends. If the “#” key has been pressed, the routine continues toST1036 where a determination is made as to whether the “#” key is the first key pressed. If the “#” key is not the first key pressed, the Outgoing Cell Call routine (seeFIG. 5I) is entered atST1037. If the “#” key is the first key pressed, the Outgoing Landline routine is entered atST1038. In short, if the “#” key is pressed before the user enters a telephone number, the communication device is connected toline pair104 and the user can thereafter enter a telephone number to make a landline call. If the “#” key is pressed after the user enters a telephone number, an outgoing cell call is initiated viacellular communication device108 using the entered telephone number.
• FIG. 5F is a flowchart showing an illustrative Phone On-Hook routine. AtST1040, a determination is made as to whether the user was just on a cell call. If not, the routine continues toST1042. If so, an “End Call” command is sent to the cellular telephone atST1041 and the routine thereafter proceeds toST1042. AtST1042, all flags except the “cell call on hold” and “landline call on hold” flags are cleared and then first switch30 is opened andsecond switch32 is closed atST1043. The routine then continues toST1044 andST1045 at whichaudio switch38 is opened andthird switch34 is closed, respectively. The routine then checks for incoming calls atST1046. A determination is made atST1047 as to whether the cell call on hold flag is set and, if not, a determination is made atST1048 as to whether the landline call on hold flag is set. If the cell call on hold flag is set, the incoming cell call flag is set atST1049 and incoming calls are checked atST1050. If the landline call on hold flag is set atST1048, the incoming landline call flag is set atST1051 and incoming calls are checked atST1050. If the landline call on hold flag is determined not to be set atST1048, the routine ends.
• FIG. 5G is a flowchart showing an illustrative Outgoing Landline Call routine. This routine is accessed, for example, from the Outgoing Call routine ofFIG. 5E if a determination is made that a landline call is to be made. AtST1060, the routine closes first andsecond switches30,32 and opensthird switch34. The routine then continues toST1061 at which the landline call flag is set. At this point, the communication device is connected toline pair104 and the user places a landline call in the normal way. Thereafter, the routine ends. While on a landline call, keypresses by the user are ignored.
• FIG. 5H is a flowchart showing an illustrative Flash Button Pressed routine. AtST1070, the routine determines whether the user is on a landline call. If so, the routine proceeds toST1071 where a determination is made as to whether the incoming cell call flag or the cell call on hold flag is set. If so, the routine proceeds to put the landline call on hold and connect to the cell call (ST1072) by closing hold switch12 (ST1073), opening first switch30 (ST1074) and closingthird switch34 and audio switch38 (ST1075). The routine then proceeds to the Incoming Cell Call (seeFIG. 5C) atST1076. If the incoming cell call flag and the cell call on hold flags are not set atST1071, the routine then performs a landline flash (ST1077) by opening second switch32 (ST1078), waiting 400 milliseconds (ST1079) and then closing second switch32 (ST1080). If the routine determines atST1070 that the user is not on a landline call, the routine proceeds toST1081 where a determination is made as to whether the incoming landline call flag or the landline call on hold flag is set. If so, the routine proceeds to put the cell call on hold and connect to the landline call (ST1082) and then goes to the Incoming Landline Call routine (seeFIG. 5D) atST1083. If the incoming landline call flag and the landline call on hold flags are not set atST1081, the routine does a cell phone flash (ST1084) by sending an answer key command to the cellular telephone (ST1085).
• FIG. 5I is a flowchart showing an illustrative Outgoing Cell Call routine. This routine is accessed, for example, from the Outgoing Call routine ofFIG. 5E if a determination is made that a cell call is to be made. AtST1090, the routine closesthird switch34 andaudio switch38.First switch30 is opened andsecond switch32 is closed atST1091. The routine then dials the numbers stored atST1035 inFIG. 5E on the cell phone atST1092. If dialing is not finished atST1093, a determination is made atST1094 as to whether the phone on-hook flag is set. If not, the routine returns toST1092 to continue dialing the numbers on the cell phone. If the on-hook flag is set, the Phone On-Hook routine (seeFIG. 5F) is entered atST1095. If the dialing is finished atST1093, the on cell call flag is set (ST1096) and the routine ends.
• FIG. 5J is a flowchart showing an illustrative Incoming Calls Check routine. AtST1100, the routine determines whether there is an incoming landline call or whether the incoming landline call flag is set. The determination of whether there is an incoming landline call is made by checking the hardware (e.g., the voltages on line pair104). If either condition is satisfied atST1100, the routine proceeds toST1101 where a determination is made as to whether the user is on a cell call. If so, the Call Waiting routine (seeFIG. 5K) is entered (ST1102). If the user is not on a cell call, the routine rings the telephone normally, opensfirst switch30 and closes third switch34 (ST1102). The incoming landline call flag is then set atST1103 and the routine proceeds toST1109. If neither condition is satisfied atST1100, the routine determines whether there is an incoming cell call or whether the incoming cell call flag is set atST1104. To determine whether there is an incoming cell call, the signal level on the audio pin of the cellular telephone's data connector may be compared to a predetermined level. If the signal level exceeds this predetermined level, an incoming cell call is determined to be present. In an alternative implementation,DSP22 may be responsive to an incoming cell call signal provided via telephone's data connector overbus48. If the determination atST1104 is “NO”, the routine ends. If the determination atST1104 is “YES”, the routine proceeds toST1105 where a determination is made as to whether the user is on a landline call. If so, the Call Waiting routine (seeFIG. 5K) is entered atST1106. If not, the routine rings the telephone, opensfirst switch30 and closes third switch34 (ST1107). Preferably, the ring atST1107 is different than the ring for an incoming landline call. This enables the user to know before answering that the incoming call is a cell call. AtST1108, the incoming cell call flag is set and the routine then proceeds toST1109. AtST1109, the routine continuously checks whether the incoming call is stopped. If so, the ringing of the telephone is stopped atST1110 and the cell call on hold flag, the landline on hold flag, the incoming landline call flag or the incoming cell call flag is cleared atST1111.
• FIG. 5K is a flowchart showing an illustrative Call Waiting routine. AtST1120, the routine checks whether the user is on a cell call. If so, the routine generates a special call waiting tone (ST1121), enables the Ten Second Timer routine (ST1122), and sets a call waiting flag (ST1123). Thereafter, the routine ends. The normal call waiting tone is 440 Hz. In order to allow the user to determine the type of call waiting while he/she is on the telephone, the user will hear a 1500 Hz tone. Hearing this tone, which is significantly different than the normal call waiting tone, will tell the user that another type of call is waiting. If the user is not on a cell call, the routine closes thehold switch12 atST1124 and then opensfirst switch30 and closesthird switch34 atST1125. A special call waiting tone is generated atST1126 and the Ten Second Timer routine is enabled atST1127.First switch30 is then closed atST1128 and holdswitch12 andthird switch34 are opened atST1129. The call waiting flag is set atST1130 and thereafter the routine ends.
• FIG. 5L is a flowchart showing an illustrative Ten Second Timer routine. The routine first checks whether ten seconds have passed atST1140. If not, the routine determines whether the call waiting flag is set atST1141. If so, the routine returns toST1140 to determine whether ten seconds have passed. If not, the routine proceeds toST1143. If the routine determines atST1140 that ten seconds have passed, a check is made as to whether the call waiting flag is set atST1142. If not, the routine ends. If so, the routine proceeds toST1143 where the timer is disabled and toST1144 where the Call Waiting routine is entered.
• FIG. 6 is a functional block diagram of an example implementation of interface circuitry. In this example, the interface circuitry is configured to connect the communication device for a wireless call in response to the input of a predetermined code (e.g., *32) and otherwise connect the communication device for a PSTN call.Communication device102 is an ordinary cord or cordless telephone that may be located in a home or office.Switch502 is an electronic switch for connecting and disconnecting the telephone from the PSTN.Tri-state503 is an electronic switch that places the phone line in a high impedance state.Wall jack504 is a standard RJ11 wall jack found in homes and offices.Network interface505 is circuitry that interfaces the system to the PSTN. This interface complies with all FCC regulations for attaching electronic equipment to the PSTN. When thecommunication device102 is in use by the user, thenetwork interface505 places the proper voltages, resistances and impedances on the telephone line of the PSTN. This keeps the telephone available for incoming and outgoing calls.Ring detector506 detects incoming calls from the PSTN and provides an incoming call detection signal to themicrocontroller507.Ring generator508 rings thecommunication device102 when an incoming cellular call is detected.Microcontroller507 provides the overall control of the interface circuitry. On/off-hook circuit509 detects when thecommunication device102 is on-hook (i.e., not in use) and off-hook (i.e., in use). This circuit sends on-hook and off-hook signals tomicrocontroller507 as appropriate.DTMF circuit510 detects and decodes the buttons pressed by the user oncommunication device102 and provides this information tomicrocontroller507.Audio interface511 selectively provides an audio path between the cellular phone andcommunication device102.RF interface512 contains a very sensitive RF antenna that is capable of detecting and capturing very weak cellular signals.RF interface512 increases the sensitivity/signal range of the cellular telephone that is connected to the system.Cell phone interface513 connects the cellular telephone to the interface circuitry so that calls, data, audio, etc. can be sent to and received from the cellular telephone.Power distribution system514 connects to all the elements shown inFIG. 6. The power distribution system controls, regulates and distributes power to these elements.
• FIGS. 7A-7F are flowcharts illustrating example operations involving the interface circuitry shown inFIG. 6.FIG. 7A shows example operations that occur when the telephone goes into the off-hook state.FIG. 7B shows example operations that occur at the end of all calls.FIG. 7C shows example operations that occur when a cell call is received while the user is on a landline call.FIGS. 7D and 7E show example operations that occur when a landline call is received while the user is on a cell call.FIG. 7F shows example operations that occur when there is an incoming call. Additional description of these flowcharts is provided in Application No. 60/394,283, filed Jul. 9, 2002, the contents of which are incorporated herein in their entirety.
• FIG. 8 is a circuit block diagram of another example ofinterface circuitry106. In this example,interface circuitry106 does not use hardware switches and the switching is done in software by compressed digital audio as opposed to the raw analog audio signal. The functionality of theFIG. 8 interface circuitry is the same as that of theFIG. 2 interface circuitry; however, theFIG. 8 interface circuitry provides more robustness. For example, theFIG. 8 interface circuitry converts all audio to a digital format, which allows the audio signals to be enhanced using conventional digital signal processing techniques. For example, if the audio to/fromline pair104,communication device102, and/or thecellular phone108 is unclear or noisy,DSP122 can remove this unwanted noise from the audio signal. The audio fromline pair104 can be digitized byDAA136, and the audio fromcommunication device102 andcellular telephone108 can be digitized by ringingSLIC120. In the following description,communication device102 is assumed to be a telephone, although, as noted above, the invention is not limited in this respect.
• The user makes a landline call as follows. First, the user picks up the telephone (i.e., places the telephone in an off-hook state) and enters a predetermined code for a landline call. The user then dials the telephone number of the called party. RingingSLIC120 detects the numbers being dialed and sends this information toDSP122.DSP122 instructsDAA136 to go off hook, andDAA136 dials the telephone number of the called party. If the called party answers,DAA136 captures, digitizes and compresses the audio from the called party that is communicated overlandline104. This compressed digital data is communicatedDSP122.DSP122 can optionally process the compressed digital data using digital audio techniques such as audio quality enhancement.DSP122 sends the digital audio to ringingSLIC120 via a digital audio data bus45 (e.g., a PCM serial bus). Althoughbusses44 and45 are shown separately, they may be provided as a single bus in another implementation. RingingSLIC120 decompresses the audio and converts the digital signal back into analog audio signals, which are then supplied to the telephone so that the user can hear them.
• Analog audio from the calling party is supplied to ringingSLIC120, which digitizes and compresses the audio and communicates the digital audio signal toDSP122 over the digital audio path.DSP122 can optionally utilize digital audio processing techniques on the digital audio to, for example, provide audio enhancement. The digital audio signal output fromDSP122 is supplied toDAA136, which decompresses the audio and converts the digital signal to an analog signal that is then transmitted to the called party vialine pair104.
• To make a cellular call from the telephone, the user follows the steps discussed above with respect to the interface circuitry ofFIG. 2A. Call conferencing between cellular and landline calls may be accomplished by connecting bothDAA136 andcellular phone108 to ringingSLIC120 simultaneously.
• The above-described arrangements also advantageously permit data other than audio data to be sent fromwireless communication device108 tocommunication device102. For example, the names and associated telephone numbers that are stored in a cellular telephone phonebook may be stored into memory (such as memory42) each time a cellular telephone is connected to the interface circuitry (e.g., by being placed incradle214 inFIG. 4). These names and telephone numbers may be stored using the Caller ID (CID) protocol and forwarded to a CID-enabledcommunication device102 for viewing. This protocol is described in documents such as Calling Identity Delivery On Call-Waiting, TR-NWT-000575; Caller Identification With Call Waiting: Request for Information From Customer Premises Equipment Suppliers, RFI 91-03; SPCS Customer Premises Equipment Data Interface, TR-TSY-000030, Bellcore,Issue 1, November 1988; Call Waiting LSSGR, Feature Specific Document (FSD) 01-02-1201, TR-TSY-000522,Issue 2, July 1987, CLASS Calling Name Delivery and Related Features Generic Requirements, TA-NWT-001188,Issue 1, Bellcore, March 1991; and CLASS Feature: Calling Number Delivery, TR-TSY-000031, Bellcore, Issue 3, January 1990; and Caller Identification With Call Waiting: Request for INformation From Customer Premises Equipment Suppliers, RFI-91-03, April 1991. Each of these documents is incorporated herein by reference. Briefly, caller ID uses the time interval between the first two rings of the called-party telephone to transmit information to that telephone. The information is FSK-modulated and includes a preamble followed by data including a message type, a data count, and data such as month, day, hour, minute, phone number, name, etc. Many new home and office telephones have built-in CID receivers and LCD screens. As described below, by using the CID transmission protocol, the systems and methods described herein provide for sending information such as e-mail, text, messages, cellular telephone directories and the like tocommunication device102. Thus, by using theCID type 1 and/or CID type 2 (CIDCW) protocols, the communication systems and methods described herein can send information to thecommunication device102.
• By way of illustration, stored telephone numbers in a cellular telephone's phonebook may be displayed on communication devices such as telephones that have built-in caller-ID LCD screens. This is advantageous because it enables users of standard landline telephones to retrieve names and telephone numbers stored within their cellular telephones and then place a cellular or landline call from the standard landline telephone using these names and telephone numbers. This feature may be implemented as follows.
• Each time a cellular telephone is connected to the interface circuitry, the names and telephone numbers stored in the memory of the cellular telephone are synchronized with the names and telephone numbers stored inmemory42. Specifically, DSP22 (122) detects the presence of a connection to a cellular telephone and sends a command to the cellular telephone to transfer the contents of its phonebook. DSP22 (122) updates the phonebook contents in memory42 (142) based on the contents transferred from the cellular telephone. These steps are performed each time the cellular telephone is connected to the interface circuitry.
• To view names and/or telephone numbers that are stored in the cellular telephone's phonebook, the user picks up the standard landline telephone. At this point, the user can do one of four things: (1) make a landline telephone call as described above; (2) make a cellular telephone call as described above; (3) make a voice-over-IP call as described above, or (4) enter a predetermined code to view the contents (names and telephone numbers) of the cellular telephone's phonebook. By way of example, the predetermined code for view the phonebook contents may be “*7”, although it will be appreciated that the invention is not limited in this respect.
• Ringing SLIC20 (12) detects the user's inputs and forwards the inputs to DSP22 (122). If the DSP determines that the user has input the predetermined code for accessing the phonebook, the DSP retrieves the first name and telephone number from the phonebook stored in memory42 (142) and encodes the name and telephone number using the CID protocol. DSP22 (122) then instructs ringing SLIC20 (120) to send an alert tone to the CID receiver within the user'scommunication device102. Upon receiving an acknowledge tone from the CID receiver via ringing SLIC20 (120), DSP22 (122) forwards the CID packet (name and telephone number) to ringing SLIC20 (120). Ringing SLIC20 (120) then transmits the CID information to the CID-enabledcommunication device102, which then displays the name and telephone number ondisplay210. At this point, the user has a number of options. First, the user can press a predetermined code to dial the telephone number that is displayed. While in the cellular phonebook mode, the user can press one predetermined code (e.g., “*”) to place the call viacellular phone108 or another predetermined code (e.g., “#”) to place the call using the landline. Second, the user can press a predetermined code to end the phonebook mode. Third, the user can press a predetermined code to go to the next name in the phonebook. Fourth, the user can press a predetermined code to go to the previous name in the phonebook. Fifth, the user can press one of thenumbers 2 through 9 to jump to the first name that begins with the first letter corresponding to the number. For example, pressing “6” would jump to the first name beginning with “M” in the phonebook. Pressing “6” again would result in the display of the first name beginning with “N”, while pressing “6” yet again would result in the display of the first name beginning with “O”.
• By utilizing the CID protocol, text messages from any source can be transmitted to a CID enabled home telephone. An example of this is as follows. Because the system has the capability to retrieve data from the internet, a user may retrieve stock quotes via the internet to their CID enabled telephone. To enable the stock quote system, the user presses a predetermined code (e.g., “*78”) and the corresponding key which represents the ticket symbol for the stock they are interested in.DSP22 andDAA36 are configured to access a web site having the desired information. For example if the user wants to get a quote for America Online (AOL). The user will press the “2” button once (which represents the letter A), and the “6” button three times (which represents O), and finally the “5” button 3 times (which represents L). The user then presses the # button. Although the user will see the letters “AOL” on the screen, internally DSP22 (122) will recognize the following number sequence (i.e., 2666777#). The system will retrieve the stock quote from the internet and transmit the quote to the telephone using the CID protocol.
• While a user is on a call,communication device102 may display indicia indicating the call type (e.g., whether the user is currently on a landline call or on a wireless call). In one example implementation,DSP22 may forward text to the communication device using the CID protocol. If the user is on a landline call, the text may be “landline” or “PSTN” or some other text for informing a user that he or she is currently on a landline call. If the user is on a wireless call, the text may be “cell” or “wireless” or some other text for informing the user that he or she is currently on a wireless call. In addition,communication device102 may display indicia indicating call status (e.g., dialing, connecting, busy, etc.). Like the call type indicia, the call status indicia may be provided tocommunication device102 as text fromDSP22 using the CID protocol. Still further, user instructions may be provided on the display ofcommunication device102. For example, when the communication device goes off-hook, instructions like “press # to make a landline call” and/or “enter number followed by # to make wireless call” may be displayed to guide the user. When the user is on a call and there is an incoming call, an instruction like “press flash to connect to incoming call” may be displayed. It will be readily apparent that more sophisticated indicia such as images or graphics are possible. For example, communication device102 (e.g., handset202) may be provided with on-board memory for storing images, graphics and even audio and video for displaying call type data, call status data and/or user instructions. The appropriate data may be read out from the memory in response to instructions fromDSP22.
• In another example embodiment,base unit204 ofFIG. 4 may be provided with its own display (not shown). The display may be used to provide the call type data, call status data and/or user instructions discussed above (in textual, graphic, image, and/or video form, for example). These displays may be based on data stored inmemory42. In addition, the display may be used to display any other data (including video, images, and graphics) stored inmemory42 or obtained from the landline or the wireless communication network. Audio corresponding to the video may be output via the base unit's speaker.
• In still further arrangements, DSP22 (122) may be programmed to recognize the wireless communication device that is placed in the cradle using, for example, an identifier associated with the device. Alternatively, the owner of the device may input a predetermined code using a keypad of the device to identify the device. In this case, DSP22 (122) may maintain data for that device in an area of memory42 (142). Thus, for each of a plurality of different devices, memory42 (142) may contain, for example, a telephone directory (names and numbers) for that device. Thus, a user of thecommunication device102 may be provided a display of telephone numbers that correspond to the device currently in the cradle. In addition, the user may input names and telephone numbers for the directory usingcommunication device102. Memory42 (142) may also maintain preferences for each different wireless device connected to the cradle. For example, each wireless communication device may have a list of do not accept call numbers or restricted calling times.
• The above-described example embodiments enable cellular phone-users to receive and place cellular phone calls using their standard home and/or office telephones and bypass the local telephone company. In addition, a high-gain (e.g., 6 dB) directional wireless antenna may be provided that allows users to place and make their wireless calls in areas where the wireless reception is very weak such as homes and offices. This high-gain cellular antenna permits is particularly advantageous to those wireless users who are not able to use their wireless devices at home during the times when long distance calls are promised to be free or at reduced rates (i.e., nights and weekends).
• The above-described embodiments do not require users to have multiple line telephones installed in their homes and/or offices and communication devices that are connected to the interface circuitry can still be used to place and receive regular land-line calls. These embodiments also provide built-in call waiting for both wireless and regular landline calls. While users are on a regular landline call, any incoming wireless call will produce a call waiting tone and the reverse is true when a user is on a wireless call. The embodiments allow users to receive and/or place all calls through both wireless and landline telephones that are connected to the interface circuitry. The wireless telephone charges while in the cradle.
• The above example embodiments show a landline communication device connected via interface circuitry to a single cellular telephone. However, the invention is not limited in this respect and the landline communication device may be connected to two or more devices that provide access to different communication networks. For example, the arrangement shown inFIG. 4 may be modified to provide cradles for both a cellular telephone and a satellite telephone. In this case the interface circuitry may be configured to permit cellular calls to be made by entering one predetermined code into the landline communication device and to permit satellite calls to be made by entering another different predetermined code into the landline communication device. TheFIG. 4 arrangement may also be modified to provide cradles for two or more cellular telephones and/or two or more satellite telephones. This may be useful for households or offices having two or more persons each of whom has his/her own cellular or satellite telephone. Each person may be assigned a different predetermined code so that the interface circuitry can access his/her cellular telephone to place calls.
• The systems and methods described herein can even be used in the event that the interface circuitry is not connected to a line pair for the PSTN. This might be the case, for example, in areas or regions where there is no access to the PSTN. In such areas and regions, wireless communication over a cellular network, for example, may be the primary method for telecommunication. If the interface circuitry described herein is used in this situation, users may still place and receive cellular calls using a conventional landline telephone, even though the interface circuitry is not connected to a line pair for the PSTN. Because of the limited talking time on wireless telephones due to limited battery life, heating up of the device, or poor ergonomics, the systems and methods described herein allow the user to extend his/her talking time.
• While the invention has been described in connection with certain embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (8)

1. A communication system comprising:

a communication device; and

interface circuitry connected to a single ring-tip line pair of a landline communication network and to a wireless communication device for a wireless communication network, wherein the interface circuitry selectively connects the communication device to the ring-tip line pair for landline and internet calls and to the wireless communication device for wireless calls.

2. The communication system according toclaim 1, wherein the interface circuitry determines whether to place a landline, internet or wireless call in response to a user input.

3. A communication system comprising:

a communication device having a display; and

interface circuitry connected to a ring-tip line pair of a landline telephone network and to a wireless communication device for a wireless communication network, the interface circuitry selectively connecting the communication device to the ring-tip line pair for landline calls and to the wireless communication device for wireless calls,

wherein the display of the communication device displays indicia indicative of whether the communication device is currently engaged in landline or wireless call.

4. The communication system according toclaim 3, wherein the display further displays user instructions.

5. The communication system according toclaim 3, wherein the display further displays call status indicia.

6. A method comprising:

selectively connecting a communication device to a ring-tip line pair of a landline communication network for landline calls and to a wireless communication device for a wireless communication network for wireless calls; and

displaying indicia to the user indicative of whether the communication device is currently engaged in landline or wireless call.

7. The method according toclaim 6, wherein the indicia is displayed on a display of the communication device.

8. A storage medium storing computer-executable instructions for performing the steps set forth inclaim 6.

Images