System and method for simultaneously controlling ringing at local and remote telephones

What is claimed is:

1. A telephone device operable to receive an incoming call from a calling telephone instrument on a subscriber telephone line coupled to said telephone device and to connect said incoming call to a first telephone instrument coupled to said telephone device and to connect said incoming call to a selected second telephone instrument, said telephone device comprising:

means for initiating and maintaining a three-way conference connection on said subscriber telephone line between said calling telephone instrument, said telephone device, and said second telephone instrument, said three-way conference connection initiated by said incoming call directed to said subscriber telephone line;

monitoring and connecting means for monitoring said first telephone instrument during said three-way conference connection, applying a locally generated ringing cadence, and connecting said first telephone instrument to said three-way conference connection when said monitoring detects that said first telephone instrument is answered;

transceiver means coupled to said first telephone instrument and said subscriber telephone line operable to monitor energy signals from said telephone subscriber line and said first telephone instrument, said energy signals including DTMF inputs, dial tones, busy signals, ringing cadences and telephone line energy, and to generate DTMF tones in response to said detection of said monitored energy signals;

a digital processor coupled to said transceiver means, said digital processor operable to receive input signals from said first telephone instrument and said transceiver means and to generate outputs to said first telephone instrument and said transceiver means under control instructions stored in an electronic memory, said stored control instructions operable to control said three-way conference connection means, said monitoring and connecting means, said transceiver means and said first telephone instrument; and

circuitry coupled to and controlled by said digital processor for generating ringing cadences and busy signals for communication to said first telephone instrument.

2. The telephone device in claim 1 wherein said generated ringing cadence is controlled by a ringing cadence sent to said selected second telephone instrument as a result of said three-way conference connection.

3. The telephone device in claim 1 wherein said electronic memory is comprised of a first nonvolatile memory embedded in said digital processor containing said stored control instructions and a second nonvolatile memory coupled to said digital processor, said second nonvolatile memory containing data corresponding to telephone numbers of one or more remote telephone instruments.

4. The telephone device in claim 1 wherein said control instructions stored in said electronic memory further include data corresponding to a first pattern of DTMF tones received over said subscriber telephone line, said first pattern of DTMF tones operable under control of said processor to generate a busy signal for communication to said first telephone instrument if said first telephone instrument is picked up during said conference call and to prevent said processor from connecting said first telephone instrument to said conference call.

5. The telephone device in claim 1 wherein said control instructions stored in said electronic memory further include data corresponding to a second pattern of DTMF tones received from said first telephone instrument or said subscriber telephone line, said second pattern of DTMF tones operable under control of said processor to cause said telephone device to initiate and maintain conference calls with a selected telephone instrument other than said second telephone instrument when a next incoming call is received, said selected other telephone instrument being designated by DTMF tones corresponding to the telephone number of said selected other telephone instrument received from said subscriber telephone line or said first telephone instrument after the receipt of said second DTMF pattern.

6. The telephone device in claim 5 wherein said control instructions stored in said electronic memory further include security code data corresponding to a third pattern of DTMF tones received from said first telephone instrument or from said subscriber telephone line, said security code data operable under control of said processor to prevent said second pattern of DTMF tones from causing said processor to initiate and maintain said conference calls with said selected other telephone instrument other than said second telephone instrument unless said third pattern of DTMF tones is received by said telephone device immediately after said second pattern of DTMF tones.

7. The telephone device in claim 1 wherein said control instructions stored in said electronic memory further include data corresponding to a fourth pattern of DTMF tones received from said first telephone instrument or said subscriber telephone line during a call involving said first telephone instrument, said fourth pattern of DTMF tones operable under control of said processor to initiate and maintain a conference call with said second telephone instrument.

8. The method of controlling an incoming telephone call from a calling telephone instrument directed to a called telephone instrument so that the incoming call may be answered by the called instrument or by a selected one of a plurality of other telephone instruments, each having a unique called number identification, the method comprising the steps of:

receiving the incoming call at a telephone device coupled to the called telephone instrument;

initiating a three-way conference call on the incoming telephone line between the calling phone instrument, the telephone device and a first selected other telephone instrument; and

determining when ringing cadence is being applied to the first selected other telephone instrument, and in response to said determination, immediately applying a locally generated ringing cadence to the called telephone instrument.

9. The method set forth in claim 8 further including the steps of:

terminating the conference call to the first selected other telephone instrument if the called telephone instrument is answered first; and

maintaining the conference call between the first selected other telephone instrument and the calling telephone instrument if the first selected other telephone instrument is answered first.

10. The method set forth in claim 9 further including the steps of:

monitoring the called telephone instrument and connecting it to the conference call if the called telephone instrument is picked up during the conference call between the calling instrument and the first selected other telephone instrument.

11. The method as set forth in claim 10, the method including, whenever the first selected other telephone instrument is answered first, the further steps of:

receiving from the incoming telephone line input in the form of a first pattern of DTMF tones, the first pattern of DTMF tones operable to cause the telephone device to generate a busy signal on the called telephone instrument if the called telephone instrument is subsequently picked up and to prevent the telephone device from connecting the called telephone instrument to the conference call.

12. The method set forth in claim 10 further including the steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of a second pattern of DTMF tones, the second pattern of DTMF tones operable to cause the telephone device to initiate and maintain a conference call with a second selected other telephone instrument other than the first selected telephone instrument when the next incoming call is received, the second selected other telephone instrument being designated by DTMF tones corresponding to the telephone number of the second selected other telephone instrument received from the called telephone instrument or the incoming telephone line after the receipt of the second pattern of DTMF tones.

13. The method forth in claim 12, further including the steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of security code data corresponding to a third pattern of DTMF tones, the security code data operable to prevent the second pattern of DTMF tones from causing the telephone device to initiate and maintain a conference call with a second selected telephone instrument other than the first selected telephone instrument unless the third pattern of DTMF tones is entered immediately after the second pattern of DTMF tones.

14. The method set forth in claim 10 including, whenever the called telephone instrument is answered first or used to make an outbound call, the further steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of a fourth pattern of DTMF tones, the fourth pattern of DTMF tones operable to cause the telephone device to initiate and maintain a conference call with the first selected telephone instrument.

15. The method set forth in claim 8 further including the step of delaying the ringing of the called telephone instrument.

16. The method of controlling an incoming telephone call from a calling telephone instrument directed to a called telephone instrument so that the incoming call may be answered by the called instrument or by a selected one of a plurality of other telephone instruments, each having a unique called number identification, the method comprising the steps of:

receiving the incoming call at a telephone device coupled to the called telephone instrument;

initiating and maintaining a three-way conference call on the incoming telephone line between the calling phone instrument, the telephone device and a first selected other telephone instrument;

determining when ringing cadence is being applied to the first selected other telephone instrument and, in response to said determination, immediately applying a locally generated ringing cadence to the called telephone instrument; and

monitoring the called telephone instrument during the three-way conference call and connecting the called telephone instrument to the three way conference call when the monitoring detects that the called telephone instrument is answered.

17. The method set forth in claim 16 further including the step of delaying the applying of the ringing cadence to the called telephone instrument.

18. The method set forth in claim 16 further including the steps of:

terminating the conference call to the first selected other telephone instrument if the called telephone instrument is answered first; and

maintaining the conference call between the first selected other telephone instrument and the calling telephone instrument if the first selected other telephone instrument is answered first.

19. The method set forth in claim 18 further including the steps of:

continuing to monitor the called telephone instrument and connecting it to the conference call if the called telephone instrument is picked up during the conference call between the calling instrument and the first selected other telephone instrument.

20. The method as set forth in claim 19, the method including, whenever the first selected other telephone instrument is answered first, the further steps of:

receiving from the incoming telephone line input in the form of a first pattern of DTMF tones, the first pattern of DTMF tones operable to cause the telephone device to generate a busy signal on the called telephone instrument if the called telephone instrument is subsequently picked up and to prevent the telephone device from connecting the called telephone instrument to the conference call.

21. The method set forth in claim 20 further including the steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of a second pattern of DTMF tones, the second pattern of DTMF tones operable to cause the telephone device to initiate and maintain a conference call with a second selected other telephone instrument other than the first selected telephone instrument when a next incoming call is received, the second selected other telephone instrument being designated by DTMF tones corresponding to the telephone number of the second selected other telephone instrument received from the called telephone instrument or the incoming telephone line after the receipt of the second pattern of DTMF tones.

22. The method set forth in claim 21, further including the steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of security code data corresponding to a third pattern of DTMF tones, the security code data operable to prevent the second pattern of DTMF tones from causing the telephone device to initiate and maintain a conference call with a second selected telephone instrument other than the first selected telephone instrument unless the third pattern of DTMF tones is entered immediately after the second pattern of DTMF tones.

23. The method set forth in claim 19 including, whenever the called telephone instrument is answered first or used to make an outbound call, the further steps of:

receiving from the called telephone instrument or the incoming telephone line input in the form of a fourth pattern of DTMF tones, the fourth pattern of DTMF tones operable to cause the telephone device to initiate and maintain a conference call with the first selected telephone instrument.

Description Submit all comments and votes

TECHNICAL FIELD OF THE INVENTION

This invention relates to telephone call devices and more particularly to a telephone connection device that will simultaneously ring an attached local telephone as well as a selected remote telephone, such as a cellular telephone, whenever an incoming call is directed to the local telephone.

BACKGROUND OF THE INVENTION

A common problem facing telephone users today is that they are using many different telephones, each with a different directory number, to receive their calls. The problem is compounded by the fact that many of these numbers are connected to dissimilar systems. The classic illustration of this is when a person uses a wireless (or cellular) phone, an office phone, and a home phone. Other parties don't know which number to call that person on to actually get that person immediately. As wireless (or cellular) telephone technology improves, the coverage is getting more comprehensive, the service is becoming more affordable, and the cellular phone is beginning to become the first choice of telephone numbers at which a person can be reached. Unfortunately, it is not the phone number that is published in the Yellow Pages or the White Pages and, therefore, it is not the phone number by which a person is generally identified. It is an unlisted number given by the cellular service company and because of the per-minute cost to the user, the user is very selective about making the number available to others. The problem, then, is to allow a caller to call just one (primary) phone number, the existing one that is published on business cards and in the Yellow Pages or the White Pages, and nonetheless reach the called person on a second phone, such as their cellular phone, as well as on the primary listed phone.

The basic telephone system is designed to route a single call to a single phone number. The telephone switching network can be modified to ring two phone numbers with one call. But, in the industry today, the only way to do that is to have a third number allocated which people then call and, within the complex network of the centralized system, a service control point actually receives that call and then generates two new calls on the network. So, instead of having one call from one person to another, one now has one call to a machine, which then generates two new calls, so that there are three phone calls on the network. All of these network resources are held up while two phones are ringing until one is answered, and then the telephone system reverts back to one caller, one phone number. This method of connection also requires the use of a database to store information pertaining to the called customer and to complete the transaction.

This method is very expensive because of the needed central office equipment. Also, there are standards yet to be written to allow a central service to generate two calls from one. Thirdly, there are costs due to the administration of the database. This follows since the central computer must know the two phone numbers that the incoming call is trying to reach. The incoming call needs to be triggered in such a way that it is not routed directly to either phone number. It must be put on hold and the information routed to the computer to fetch the two needed phone numbers.

SUMMARY OF THE INVENTION

The foregoing problems are solved by letting the telephone network deliver the call as it does best; by directing the calling telephone to the actual called phone. The incoming calling signal is delivered to the actual called "local" phone number, but the present invention is placed in between the "local" called phone and the incoming telephone subscriber line at the "called" number end. At that point, the telephone network has its resources connected as it would to deliver a phone call to one number. Then, using a network resource that is standard now in almost all telephone exchanges, the present invention initiates a three-way call (or conference call) wherein a second "remote" telephone number, stored in the present invention, is dialed. The incoming call is put on hold, the remote phone number is dialed very quickly. The original call and the conference call are bridged so that the caller, instead of hearing the original ringing cadence at the local phone will now hear the remote phone number's ringing cadence. Thus, the caller hears a ringing phone at the number originally called, however, this ringing is being controlled by the conference call connection, and not by the original called line. The present invention also rings the originally called local phone while the phone network is ringing the remote phone number, so that both phones are ringing at the same time.

If the local phone is answered first, the call is immediately connected to that phone and the conference bridge is dropped. If the remote phone is answered first then, the present invention stays on the line in a supervisory fashion to keep the conference open and monitor the call until finished, whereupon the present invention will drop the conference bridge, hang up, and wait for the next incoming call to the local phone.

The present invention also has other features to properly connect calls. If the remote phone number is answered, then the local phone can be locked out by pressing "##9" (or any designated combination) on the remote phone. The local phone will then hear only a busy tone. A third person cannot eavesdrop on the call. If "##9" is not invoked, one can still have a three-way call. Then, if somebody picks up the local phone, he or she can join the conference call in progress.

Another function of the present invention is that if the local phone is answered, one can again press "##9" on the local phone and thereby invoke a three-way conference call. The present invention will then invoke the dual ringing function and will call the remote phone using the conference call feature. The person on the local phone can then answer the remote phone (i.e., their cellular phone), hang up the local phone and carry on the conversation without having to dial a new phone number or disconnect temporarily.

Similarly, if one is talking on the remote cellular phone and then enters the home or office where the local phone is located, one can pick up the local phone and hang up the remote cellular phone and continue the call. In this manner, the two phones (remote and local) seem to be extensions on the same phone line.

Another feature of the invention is that it need not be located on the subscriber's premises but could in fact be anywhere between the local phone and the switching network as long as the present invention has access to the subscriber line for the local phone. Another feature of the invention is that no additional line resources are required in that the second line is called by invoking a three-way conference bridge which exists today in the telephone switching network. In an alternate embodiment, a person could connect the present invention to two separate local lines and avoid the conference call feature. This, however, will require a second resource which is not necessary in our preferred embodiment and is also more expensive since the cost of two phone lines at a subscribers home or office exceeds the cost of a single phone line with a conference call feature.

The present invention is superior to call forwarding, also. When a person uses call forwarding, the telephone network delivers the call to the local telephone line, is interrupted by the call forwarding feature, and then reroutes the call to the new number. The local telephone does not ring. A person must remember to turn on the call forward feature in order to send calls to the second number and must also remember to disable it when returning to the first number, or else no calls will arrive at the first number. Research has shown that people very often forget, and two or three days may pass before they realize they are not receiving phone calls. With the concurrent ringing feature of the present invention, both phones always ring without any invocation of a function. Once the invention is in place in the local telephone line, the two phones will behave just like two extension phones that are connected to the same subscriber line.

The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

FIG. 1 shows the microprocessor which controls all of the functions of the present invention. The microprocessor is also connected to and interacts with a microcircuit which monitors the subscriber's phone line and generates DTMF tones;

FIG. 2 shows the principal connectors of the present invention and the switching and detection circuitry which interfaces between the microprocessor shown in FIG. 1 and the attached phone and subscriber phone line;

FIG. 3 shows the internal power supply of the present invention as well as circuitry for generating dial tone, a busy signal and ringing voltage for the attached phone; and

FIG. 4 shows the present invention connected to a subscriber line and a telephone instrument.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows system 10, controlled by processor 100 which, in a preferred embodiment, is driven by crystal isolator circuit 103 and associated capacitors 104 and 105 at a rate of 3.579545 megahertz. Processor 100 is connected to DTMF transceiver 110 and nonvolatile RAM 115. Nonvolatile RAM 115 stores one or more telephone numbers corresponding to one or more remote telephones associated with the telephone number of the subscriber line to which the present invention and the local phone are connected. Nonvolatile RAM 115 is also used to store programmable variable data related to the functions of the present invention, such as a variable time period for "flash hooks" on the subscriber telephone line and a unique I.D. number used to derive an access security code.

Processor 100 can be implemented in numerous embodiments. In a preferred embodiment of the present invention, processor 100 is a controller that contains a microprocessor and an embedded ROM on the same chip due to the low cost of such devices. The processor 100 used in the preferred embodiment is a general purpose microprocessor made by numerous electronics manufacturers. It is a member of the Intel 8051 family of microcircuits. The DTMF transceiver 110 in a preferred embodiment is a highly integrated telephone DTMF transceiver with energy detector by Silicon Systems. The DTMF transceiver 110 is capable of monitoring energy on the telephone lines as well as receiving and generating DTMF tones.

Alternate embodiments of the present invention may utilize microprocessor chips connected to external memories such as ROMs, nonvolatile RAMs or removable PROMs. Other embodiments of the present invention may employ controllers that contain an internal microprocessor and an internal nonvolatile RAM. For the purposes of this disclosure, the controller used in the preferred embodiment will be referred to as "processor 100."

Also shown in FIG. 1 are pull-up resistors 120a-120c, which terminate the output pins of processor 100, DTMF transceiver 110 and nonvolatile RAM 115. Capacitor 101 and resistor 102 hold microprocessor in the reset mode after power is applied to the present invention for a brief period of time determined by the RC time constant of resistor 101 and capacitor 102.

FIG. 2 shows the two primary connections to the present invention, connector 200 (J1) and connector 205 (J2).

FIG. 3 shows connector 300 (J3) which is the primary power supply input to the present invention.

FIG. 4 shows system 10 of the present invention connected to subscriber 11 to the central office 12 of the telephone system. Telephone instrument 13 may generate incoming calls to the system 10 of the present invention or may receive calls from the local telephone 16 attached to the system 10 of the present invention. System 10 is connected by telephone wire 15 to a telephone instrument 16. Telephone instrument 14 is the remote telephone to which system 10 of the present invention sends outgoing telephone calls whenever system 10 invokes a three-way conference call to the telephone number stored in the memory of system 10. Telephone instruments 13, 14 and 16 may be standard voice telephones, answering machines, pagers, beepers, facsimile machines, cellular telephones, or computer devices capable of interfacing with the telephone system, such as by means of a MODEM.

Returning now to FIG. 2, connector 205 is the input connection of the present invention to which the existing telephone subscriber line from the telephone network is connected. When power is not connected to connector 300 of the present invention, relay 210 is de-energized and pins J2-2 and J2-3 of connector 205 are connected directly to pins J1-2 and J1-3 of connector 200, which are the connection pins for the local phone that is connected to the present invention. In other words, when no power is supplied to the present invention or it is turned off, the subscriber telephone line is connected directly to the local phone attached to the present invention by providing a short circuit from connector 205, pins J2-2 and J2-3, to connector 200, pins J1-2 and J1-3. In this mode, the present invention is invisible to the external telephone network and the local phone.

The voltage input on the J3 connector is a 12 VAC waveform that is generated by a stepdown voltage transformer that is plugged into a standard wall outlet. When power is applied to connector 300, diodes 301 and 302 in conjunction with capacitors 303 and 304 rectify and store the input voltage on connector 300 to produce a +18 VDC source and a +40 VDC source within the present invention. The rectified +18 VDC that appears across capacitor 303 is the input to voltage regulator 305. Voltage regulator 305 produces a +5 VDC output used to power several of the integrated circuits of the present invention. Power supply capacitors 390, shown in FIG. 3, are connected between the +5 VDC source and ground to filter high frequency noise from the +5 VDC source.

Immediately after power up, processor 100, shown in FIG. 1, is initially held in the reset position by capacitor 101 and resistor 102. When voltage regulator 305 generates +5 VDC, one side of capacitor 101, which is connected to the +5 VDC plane of the present invention, is raised immediately to 5 volts. Initially, there is no voltage across capacitor 101. Therefore, the other side of capacitor 101 is also raised to 5 VDC by voltage regulator 305 when power is applied. Capacitor 101 begins to charge through resistor 102 immediately. The side of capacitor 101 which is connected to resistor 102 is also connected to the reset (RST) input of processor 100. Upon power up, the RST input to processor 100 is set to 5 volts and processor 100 is held