GB2343585A - Controlling access to remote alarm programming according to caller identification - Google Patents

Abstract

A remotely controllable alarm system adapted to be connected to a telephone line comprises a memory for storing at least one authorized telephone number, a caller ID decoder for determining the source telephone number of an incoming call, a controller connected to the memory and to the caller ID decoder for comparing the source telephone number to the at least one authorized telephone number and answering the incoming call, and allowing remote access to the alarm system, if there is a match. Thus, the alarm system precludes access upon receiving an unknown number.

Description

CALLER ID PANEL ACCESS CONTROL This invention relates generally to security and other event detection systems, and more particularly to such a system that has one or more features that can be remotely controlled via access through a public switched telephone network. Typical security systems according to the invention include intruder detectors, fire detectors, personal security systems, water entry detectors, and other event detectors, typically found in a dwelling or commercial enterprise. One or more features of such systems and detection of alarms generated by such systems are usually accomplished at a remote location, such as a monitoring service or the like. While a variety of connections between the alarm system and the remote location can be used, including wired and wireless links, wide area computer networks and other public and private mechanisms, both analog and digital, it is desirable, for economic reasons, to provide such access by way of the public switched telephone network (PSTN) and even more desirable to provide such access on a shared basis with a telephone line to the residence or business that is shared by other applications, such as voice communications, fax, an answering machine, or the like.

Existing event detection systems of the type to which thé, invention relates accommodate shared access to PSTN by relying on a distinctive ringing pattern, such as a predetermined number of rings before the alarm system responds to an incoming telephone call. This may be inconvenient, because the person making the call to the alarm system would need to contact the customer and ask them not to answer a call, and to tolerate a-. possibly large number of rings, which could disturb the occupants of the home or business. Also, where answering machines or facsimile machines or the like are connected to the same line as the alarm system, these devices must be disabled so that they do not respond to the incoming call before the alarm system doues, An alternative system has been employed that also involves a distinctive ringing pattern. This system requires a caller who wishes to contact the system to call and then hang up within the first few rings, and then call back within a short time, whereupon the control panel will answer on the first ring or two. This is a less intrusive method for the occupants of the home or business, but requires coordination with other devices attached to the telephone line.

They must be set so that they don't answer on the first ring, and sequencing a number of such devices becomes more complicated.

All of the methods just described have an additional even more significant problem, namely, that the alarm system can be disabled by a burglar, or arsonist or the like, who calls the protected premises, makes contract with the control panel, and holds the line open so that it is unable to make the required outgoing call to the central monitoring station. This may give a burglar more time within the protected premises before help is called.

It is an object of the present invention to provide apparatus that overcomes the disadvantages of the prior art just described. More particularly, it is an object of this invention to provide a remotely controllable alarm system that can be accessed through the public switched telephone network, to control one or more features of the system, and which is compatible with shared access to the PSTN by other equipment, such as answering machines, facsimile machines, and the like, as well as voice usage of the PSTN line.

Summary of the Invention Briefly stated, in accordance with a presently preferred embodiment of the invention, a remotely controllable alarm system adapted to be connected to a telephone line comprises a memory for storing at least one authorized telephone number, a caller ID decoder for determining the source telephone number of an incoming call, a controller connected to the memory and to the caller ID decoder for comparing the source telephone number to the at least one authorized telephone number and answering the incoming call, and allowing remote access to the alarm system, if there is a match.

In accordance with another aspect of the invention, the memory for storing the at least one authorized telephone number is programmable memory.

In accordance with another aspect of the invention, the remotely controllable alarm system includes means responsive to the incoming call, and more particularly to information from a remote location for programming at least one feature of the alarm system. grief Description of the Drawings The novel aspects of the invention are set forth with particularity in the appended claims. The invention itself, together with further objects and advantages thereof may be more readily comprehended by reference to the detailed description of a presently preferred embodiment of the invention, taken in conjunction with the accompanying drawings, in which: Figure 1 is a block diagram of an alarm system in accordance with this invention; Figure 2 is a block diagram of the call controller of Fig. 1 ; and Figure 3 is a flow chart showing the operation of the alarm system shown in Figure 1.

Detailed Description of the Preferred Embodiments Most of the components and features of the security system are well known to those skilled in the art, and will not be described in detail here. Briefly, however, the system includes an event reporting alarm control panel 12 coupled to a plurality of event detectors 14, wireless detector interfaces 16, and key pads 18. The event detectors 14 are located throughout a protected region for detecting security related events, such as fire, intrusion, or personal emergency. Depicted are a fire detector 20, an intruder detector 22, which may be selected from a wide variety of such devices well known to those skilled in the art. The wireless detector interface 16 communicates with other similar event detectors that use radio or other wireless technologies for transmitting information about detected events to the interface 16 and control panel 12. The key pad 18 provides for data interchange with the control panel 16 and provide for local control of system status and functions. In addition to input keys, such key pads typically include display capabilities presenting information about the system and its apparatus.

The control panel 12 includes signal processors, micro processors and other well known components for analyzing signals from the detectors 14, wireless interface 16, and key pad 18. When an alarm signal is received, the panel actuates local alarm indicators 24, typically including strobe lights, horns or sirens, or light emitting diodes (LEDs) or other local displays. In addition to the local alarm indicators, the panel includes a PSTN interface 26 which has a dialer for communicating with the remote or central monitoring station 28 and reporting the alarm condition.

The control panel and its dialer interface are designed for communicating over a publicly switched telephone network (PSTN) 30 using analog formats, typically frequency shift keying or dual tone multiple frequency (DTMF). Confirmations and acknowledgments are received from the monitoring station 28 in corresponding formats. The control panel 12 and dialer interface 26 may also communicate with the monitoring station when there is no alarm, to transmit reports, status information, and the like to the central monitoring station, or to receive information and commands from the monitoring station. Such commands could include commands to cause the control panel to generate signals indicating the status of the alarm system, commands to change security access codes or the like, commands to activate or deactivate certain functions, and others that will be apparent to those of ordinary skill in the art.

The control panel 12 is connected through its PSTN interface 26 to a call controller 32. The call controller is preferably implemented as a part of the PSTN interface 26 in the control panel 12. The call controller is connected to the central monitoring station 28 by way of a telephone line 30 that may be shared with other devices, such as an answering machine 36, facsimile machine 38, modem 40, and telephone set 42.

The call controller 32 is shown in more detail in Figure 2. The call controller includes a PSTN port 44 for connecting the telephone line to the PSTN interface 26 of the control panel, and a control port 46 for receiving signals from and optionally sending signals to the control panel. The call controller also includes a telephone line port 48 for connecting the call controller, the PSTN 30.

The telephone line is connected to a caller ID decoder 50, and to a controlled switch 52. The caller ID controller 50 determines the originating telephone number of an incoming call prior to or during the initial ringing sequence. The decoded telephone number is connected to a first input 54 of a comparator 56 that has a second input 58 connected to a memory 60 for storing one or more telephone numbers from which incoming calls are accepted by the alarm signal. Preferably, the numbers are entered into the memory with a key pad 62 or similar arrangement.

The comparator 56 produces an output signal on line 64 each time the incoming number decoded by the caller or ID decoder matches one of the numbers in the memory. The output signal is connected to the controllable switch 52, which is activated to connect the telephone line to the PSTN interface of the control panel, so that the incoming call can be answered.

The arrangement shown in Figure 2 allows the control panel to respond to an incoming call each time the PSTN detects a ringing signal, since the determination that the call originated from an authorized source has already been made. The caller ID information is superimposed on a ringing signal.

Preferably, outgoing calls from the control panel are also routed through the call controller. Since the switch 52 is normally open, a control signal is provided at port 46 from the PSTN interface to the switch via line 68 to close the switch when an outgoing call is sent. Alternatively, the call controller can include a circuit for detecting an outgoing call, and actuating the switch 52 so that the call is connected to the telephone line.

The components of the call controller can be implemented as discrete circuits, preferably with a programmable micro-controller. At least the memory, switch, and comparator functions, and probably the caller ID decoder function can all be provided by a single dedicated microprocessor having a small amount of memory.

The operation of the remotely controllable alarm system, in accordance with the invention, is shown in block diagram form in Figure 3. The caller ID decoder, or a separate device detects that the phone is ringing. The caller ID decoder decodes a signal appearing on the telephone, line, and produces a telephone number at the output thereof.

The comparator receives the decoded number from the caller ID decoder, and compares it sequentially to each number stored in memory, to determine if there is a match. If there is no match, no signal is sent to the switch, and the control panel is not connected to the phone line, which can therefore be answered by any of the other devices that are connected to the phone line.

If there is a match, the comparator sends a signal to the switch, which connects the phone line to the PSTN interface of the control panel, which answers it, preferably immediately, so as to avoid answering by one of the other devices connected to the telephone line. Once the phone is answered, the control panel starts communication with the central monitoring station in the same manner as is already well known to those skilled in the art. When the session ends, as signaled either by the control panel or the central monitoring station, the signal to the switch is removed, the control panel is disconnected from the telephone line, and the procedure starts again, waiting for a ringing signal.

Although the operation of the alarm system is described in terms of waiting for a ringing signal, which can preferably be detected by a ring detector, the caller ID decoder may provide this function without the need for a separate detector.

While the invention has been described in connection with a presently preferred embodiment thereof, those skilled in the art will recognize that many modifications and changes may be made therein, without departing from the true scope of the invention, which accordingly is intended to be defined solely by the appended claims.

Claims (9)

1. CLAIMS 1. A remotely controllable alarm system connected to a telephone line, comprising: (a) memory for storing at least one authorized telephone number; (b) a caller ID decoder for determining the source telephone number of an incoming call; and (c) a controller connected to the memory and to the caller ID decoder for comparing the source telephone number to the at least one authorized telephone number and answering the incoming call and allowing remote programming if there is a match.
2. 2. The remotely controllable alarm system of claim 1 in which the memory comprises rewritable memory.
3. 3. The remotely controllable alarm system of claim 1 or 2, further comprising means responsive to the incoming call for programming at least one feature of the alarm system.
4. 4. A remotely controllable alarm system connected to a telephone line for allowing access only from a predetermined telephone number comprising: (a) a first connector adapted to be connected to an incoming telephone line; (b) a controllable switch connected between the first connector and an alarm system controller; (c) a caller ID decoder connected to the first connector for decoding the telephone number of an incoming call; (d) a memory storing the predetermined telephone numbers; and (e) a comparator connected to the caller ID decoder, the memory and the switch for activating the switch when the telephone number and the incoming call matches the predetermined telephone number.
5. 5. The remotely controllable alarm system of claim 4 in which the memory and the comparator comprise a programmable microcomputer.
6. 6. The remotely controllable alarm system of claim 4 or 5, further comprising a call detector connected to the alarm controller and to the switch for activating the switch if a call is made from the alarm system.
7. 7. The remotely controllable alarm system of claim 4,5 or 6 in which the controllable switch comprises a microprocessor.
8. 8. The remotely controllable alarm system of claim 4, further comprising a second connector adapted to connect the incoming telephone line to the alarm system.
9. 9. The call controller of claim 8, further comprising a call detector connected to the second connector and to the switch for activating the switch if a call is made from the alarm system.