Apparatus for monitoring cable television system remote equipment performance and status using a cell modem

• US 5,675,371 A
• Filed: 10/27/1995
• Issued: 10/07/1997
• Est. Priority Date: 10/27/1995
• Status: Expired due to Fees

• Current Assignee: Location Science Corporation
• Original Assignee: Location Science Corporation
• Inventors: Barringer, David
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): GRANT, CHRISTOPHER C
• Application Number:
  US08/549,300
• Time in Patent Office: 711 Days
• Field of Search: 348/6, 348/7, 348/10, 348/11, 348/12, 348/13, 348/14, 348/15, 348/16, 348/17
• US Class Current: 725/148
• CPC Class Codes: H04N 7/16 Analogue secrecy systems; Analogue subscription systems

Abstract

A wireless remote data sensor for use in the cable television industry. It senses the status of equipment in the field, such as battery backup power equipment, amplifiers, pilot and signal level monitors, and voltage level for powering active equipment, and transmits the status information using a low data rate cellular data service known as Cellemetry. It also allows the cable system operator to switch each power supply to a backup power source and back remotely for conditioning and battery capacity measurement. Cellemetry uses the forward and reverse control channels of the AMPS cellular network to communicate 32 bit data packets. Included in the sensor are a DC-to-DC converter, external power transformer or other power source, analog-to-digital converter(s), digital on-off sense input(s); a control microprocessor, a bi-directional connector for external programming, a bi-directional connection to a Cellemetry modem, a Cellemetry modem, and a cellular antenna, all of which are enclosed in an environmentally appropriate case. In addition, the present invention minimizes the number of MINs required by cycling through a series of formats of the data signal so that more than 32 bits of data can be sent, although at different times.

Claims

1. An apparatus for sensing and transmitting information from remote equipment in a cable television plant, comprising:

a) a plurality of sensors for receiving status signals from the remote equipment;

b) a processor being coupled to the sensors and formatting a data signal indicative of the status signals;

c) a Cellemetry modem being coupled to the processor, having a plurality of mobile identification numbers to which it will respond, and transmitting the data signal as an electronic serial number via a cellular telephone network, wherein said processor performs different functions depending upon which one of the plurality of mobile identification numbers was received by the Cellemetry modem.

2. The apparatus according to claim 1, wherein the status signals received by the plurality of sensors includes battery backup power equipment status, power amplifier status, status of switches, signal and pilot levels on the cable, and voltage levels on the cable.

3. The apparatus according to claim 1, wherein said processor converts the data signal into a 32 bit signal, which is treated by the cellular network as the electronic serial number of the apparatus.

4. The apparatus according to claim 1, wherein said modem outputs the mobile identification number it received to the processor, which treats the mobile identification number as a command from an operator.

5. The apparatus according to claim 1, further comprising a relay, wherein said processor changes the state of the relay if a predetermined one of the plurality of mobile identification numbers was transmitted to the apparatus.

6. The apparatus according to claim 1, wherein said processor formats the data signal in one of a plurality of predetermined formats, and cycles through the formats each time the apparatus is queried by an operator.

7. The apparatus according to claim 1, wherein said processor commands the Cellemetry modem to place a call and transmit the data signal upon a change of state of one of the status signals.

8. The apparatus according to claim 1, wherein said processor commands the Cellemetry modem to place a call and transmit the data signal when one of the status signals changes to a value outside a predetermined range.

9. The apparatus according to claim 1, wherein the processor polls all equipment it is monitoring immediately and updates the data signal prior to sending the data signal to the Cellemetry modem for transmission.

10. The apparatus according to claim 1, wherein said processor prevents the data signal from being all zeros.

11. A method for sensing and transmitting information from remote equipment in a cable television plant with a remote sensing apparatus, comprising the steps of:

a) sensing status signals from the remote equipment;

b) formatting a data signal indicative of the status signals in a 32 bit format;

c) transmitting the data signal as an electronic serial number via a cellular telephone network; and

d) controlling operation of the remote sensing apparatus by using different mobile identification numbers to query the remote sensing apparatus.

12. The method according to claim 11, further comprising the step of:

e) treating each of the plurality of mobile identification numbers as a different command.

13. The method according to claim 11, further comprising the step of:

e) cycling through a series of predetermined formats of the data signal each time the remote sensing apparatus is paged.

14. The method according to claim 11, wherein the step a) of sensing further comprises sensing battery backup power equipment status, power amplifier status, status of switches, signal and pilot levels on the cable, and voltage levels on the cable.

15. The method according to claim 11, further comprising the step of:

e) changing a state of a relay in the remote sensing apparatus if a predetermined one of the plurality of mobile identification numbers was received by the apparatus.

16. The method according to claim 11, further comprising the step of:

e) transmitting the data signal upon a change of state of one of the status signals.

17. The method according to claim 11, further comprising the step of:

e) transmitting the data signal when one of the status signals changes to a value outside a predetermined range.

18. The method according to claim 11, further comprising the steps of:

e) polling all equipment being monitored immediately before transmitting the data signal; and

f) updating the data signal prior to transmitting it.

19. The method according to claim 11, further comprising the step of:

e) preventing the data signal from being all zeros.

20. A device for monitoring remote equipment comprising:

a) means for sensing status signals from the remote equipment;

b) means for formatting the sensed status signals into a 32 bit digital signal;

c) means for transmitting the 32 bit digital signal as an electronic serial number via a cellular telephone network;

d) means for commanding the device by using a plurality of mobile identification numbers; and

e) means for changing the format of the 32 bit digital signal according to which of the plurality of mobile identification numbers the device is responding.

21. The device according to claim 20, further comprising means for controlling the remote equipment in response to a predetermined one of the plurality of mobile identification numbers received by the device.