Remote subscriber interaction system

• US 4,442,320 A
• Filed: 12/04/1981
• Issued: 04/10/1984
• Est. Priority Date: 12/04/1981
• Status: Expired due to Term

• Current Assignee: Bronzebase Ltd. (BT Group PLC)
• Original Assignee: Base Ten Systems, Inc. (CommScope Holding Company, Inc.)
• Inventors: James, Rolland T., Chebra, Ronald J.
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): George, Keith E.
• Application Number:
  US06/327,486
• Time in Patent Office: 858 Days
• Field of Search: 179/1 MN, 179/2 A, 179/2 AM, 179/5 R
• US Class Current: 379/42
• CPC Class Codes: H04M 11/002 with telemetering systems telemetering in general G08C
• CPC Class Codes: H04M 11/04 with alarm systems, e.g. fire, police or burglar alarm systems

Abstract

A central control unit (scanner) is connected across a set of subscriber loops. At each subscriber'"'"'s premises, an individual subscriber terminal unit (STU) is connected across that particular subscriber'"'"'s loop. To each STU are connected the various instrumentalities which are to be monitored by the system, e.g. fire alarms, burglar alarms, etc. FSK modulated signals in the upper part of the audible range are transmitted from the scanner to the STUs at appropriate times. The STUs reply by means of similar signals to indicate the status (e.g. alarm, or non-alarm) of the instrumentalities at the respective subscriber premises. This transmission and retransmission is interrupted when the subscriber'"'"'s telephone is off-hook. In addition, a signal below the audible range (low tone) is produced at the STU, and transmitted to the scanner over the telephone loop if, but only if, all the instrumentalities at the particular subscriber premises are in a given state (e.g. non-alarm). If not, low tone is stopped. Such stoppage is sensed by the scanner, and causes immediate transmission of the FSK signals from the scanner to the corresponding STU, even though the associated telephone is off-hook at the time. The reply to such transmission provides information about the reason for the stoppage, i.e. what is the source of the alarm.

Claims

1. A system for providing communication between a central location and instrumentalities other than a conventional telephone located at the premises of telephone network subscribers, comprising:

means for selectively transmitting signals from the central location to the telephones at different ones of said subscriber premises;

means located at said premises and connected to said telephones and responsive to said transmitted signals to retransmit to the central location from the respective subscriber premises signals in the audible telephone frequency range and of characteristics indicative of the state of said instrumentalities;

means at the central location for sensing the off-hook state of the conventional telephone at a given subscriber'"'"'s premises and responding thereto to inhibit the transmitting of said signals from the central location to that same premises;

means for transmitting to the central location a signal at a frequency below the audible range from each of the premises when the instrumentalities at the given subscriber premises are in one predetermined state; and

means responsive to at least one instrumentality being in another predetermined state to interrupt the transmission of said below-audible-range signal.

2. The system of claim 1 wherein the below-audible-range signal is transmitted from any given premises at least during off-hook conditions of the telephone at the same premises.

3. The system of claim 1 wherein the below-audible-range signal is transmitted from any given premises both during on-hook and off-hook conditions of the telephone at the same premises.

4. The system of claim 1 wherein means are provided for taking an alarm-responsive action at the central location in response to interruption of the below-audible-range signal.

5. The system of claim 1 wherein the signals transmitted from the central location are FSK modulated signals in the upper portion of the audible range.

6. The system of claim 5 wherein the signals retransmitted from the subscriber premises are also FSK modulated signals in the upper portion of the audible range.

7. The system of claim 6 wherein the FSK carrier frequencies are in the vicinity of 2700 and 2900 Hz.

8. The system of claim 1 wherein the below-audible-range signal is at a frequency of approximately 25 Hz.

9. The system of claim 1 wherein

individual wire connections are provided at the central location to each subscriber local loop;

and

multiplexing means are provided for applying the transmitted signals selectively to different ones of said individual connections in predetermined sequence, and for selectively receiving the signals from the same said individual connections in the same said predetermined sequence.

10. The system of claim 1 further comprising

means for sensing the discontinuance of the below-audible-range signal during continued sensing of the off-hook condition at a selected subscriber premises, and

means responsive thereto to transmit the signals from the central location to the same selected subscriber premises.

11. The system of claim 1 further comprising

means for sensing the discontinuance of the off-hook condition at any selected subscriber telephone, and

means responsive thereto to transmit the signals from the central location to the same selected premises.

12. A system for providing communication between a central location and instrumentalities other than a conventional telephone located at the premises of telephone network subscribers, comprising:

means for selectively tramsmitting signals from the central location to the telephones at different ones of said subscriber premises;

means located at said premises and connected to said telephones and responsive to said transmitted signals to retransmit to the central location from the respective subscriber premises signals in the audible telephone frequency range and of characteristics indicative of the state of said instrumentalities;

means at the central location for sensing the off-hook state of the conventional telephone at a given subscriber'"'"'s premises and responding thereto to inhibit the transmitting of said signals from the central location to that same premises;

means for transmitting to the central location a signal at a frequency below the audible range from each of the premises when the instrumentalities at the given subscriber premises are in one predetermined state;

individual wire connections at the central location to each subscriber local loop;

multiplexing means for applying the transmitted signals selectively to different ones of said individual connections in predetermined sequence, and for selectively receiving the signals from the same said individual connections in the same said predetermined sequence;

means for sensing the discontinuance of the below-audible-range signal during continued sensing of the off-hook condition at a selected subscriber premises; and

means responsive thereto to transmit the signals from the central location to the same selected subscriber premises.

13. A system for providing communication between a central location and instrumentalities other than a conventional telephone located at the premises of telephone network subscribers, comprising:

means for selectively transmitting signals from the central location to the telephone at different ones of said subscriber premises;

means located at said premises and connected to said telephones and responsive to said transmitted signals to retransmit to the central location from the respective subscriber premises signals in the audible telephone frequency range and of characteristics indicative of the state of said instrumentalities;

means at the central location for sensing the off-hook state of the conventional telephone at a given subscriber'"'"'s premises and responding thereto to inhibit the transmitting of said signals from the central location to that same premises;

means for transmitting to the central location a signal at a frequency below the audible range from each of the premises when the instrumentalities at the given subscriber premises are in one predetermined state;

individual wire connections at the central location to each subscriber local loop;

multiplexing means for applying the transmitted signals selectively to different ones of said individual connections in predetermined sequence, and for selectively receiving the signals from the same said individual connections in the same said predetermined sequence;

means for sensing the discontinuance of the off-hook condition at any selected subscriber telephone; and

means responsive thereto to transmit the signals from the central location to the same selected premises.