Apparatus and method for a computerized fiber optic security system

• US 7,800,047 B2
• Filed: 03/17/2005
• Issued: 09/21/2010
• Est. Priority Date: 05/03/2003
• Status: Expired due to Term

• Current Assignee: Woven Electronics LLC (Rtx Corporation)
• Original Assignee: Woven Electronics LLC (Rtx Corporation)
• Inventors: Owens, Mary H., Browning, Thomas E. Jr.
• Primary Examiner(s): Luu; Thanh X
• Application Number:
  US11/083,038
• Publication Number:
  US 20060097140A1
• Time in Patent Office: 2,014 Days
• Field of Search: 250/221, 250/222.1, 250/227.14, 340/541, 340/545.2, 340/545.3, 340555-557, 340/571, 340/825.49, 340/FOR.402, 340/552, 356/73, 356/73.1, 398/9, 398/17, 398/20, 398/21
• US Class Current: 250/227.14
• CPC Class Codes: G08B 13/186 using light guides, e.g. optical fibres

Abstract

A computerized apparatus and method for detecting unauthorized activity in a protected area in real-time using a fiber optic cable having an optical sensor line, a fiber scanning unit, and a computer. Detecting unauthorized activity is done by scanning the sensor line using the scanning unit to obtain repetitive scan signals representing the state of the sensor line, receiving scan signals at the computer, processing the scan signals to determine an initial baseline representing the normal state of the sensor line, storing the baseline, continuously monitoring the sensor line using the scan signals received in real-time by the computer, comparing the scan signal to the baseline, determining if a fault has occurred based on an predetermined attenuation change in one or more of the scan signals as compared to the baseline, generating a fault signal, and providing a warning of a fault in response to the fault signal.

Claims

1. A fiber optic security system for detecting unauthorized activity in a protected area comprising:

a fiber optic cable having an optical sensor line for transmitting and receiving scan signals;

a fiber optic scanning unit connected to one end of said optical sensor line for transmitting scan signals outbound along said optical sensor line and said scanning unit receiving return scan signals reflected back along the same said optical sensor line;

a system computer for receiving said return scan signals from said scanning unit and processing said return scan signals to determine the existence of a fault condition representing the unauthorized activity;

a computer readable medium in communication with said computer;

a computer program including computer readable instructions stored in said computer readable medium which includes,

receiving instructions for receiving said return scan signals from said scanning unit at said computer,

baseline initialization instructions for establishing a baseline signal of the sensor line based on initial information from said scan signals representing an undisturbed state of said sensor line, and storing said baseline signal in computer memory,

monitoring instructions for monitoring said optical sensor line to automatically receive said returned scan signals from said scanning unit in real-time representing the condition of said optical sensor line in real-time,

comparison instructions for determining if unauthorized activity has taken place based on a real-time comparison of said baseline signal and said return scan signals,

fault instructions for generating a real-time fault signal in response to a predetermined change in one or more of said return scan signals representing a fault condition based on said real-time comparison indicating the unauthorized activity has taken place;

evaluation instructions for processing the change in said return scan signal to determine the type of fault condition and location of the unauthorized activity that has occurred; and

said computer outputting a warning in response to said fault signal to notify an attendant that the unauthorized activity has taken place.

2. The security system of claim 1 further comprising:

an audible output device responsive to said system computer for audibly indicating the transmission of said fault signal.

3. The system of claim 1 further comprising:

a display in communication with said system computer; and

said set of computer readable instructions include display instructions for visually indicating the occurrence of a fault on said display.

4. The system of claim 3 wherein said set of computer readable instructions include mapping instructions for mapping said fault signal as a visual representation of a specific geographic location of the fault.

5. The system of claim 1 wherein said comparison instructions include instructions for determining if said returned scan signal contains attenuations, comparing said attenuations to said baseline signal, and transmitting a fault signal if said attenuations do not match said baseline signal.

6. The system of claim 5 further comprising:

a set of fault level data stored in a computer readable medium in communication with said system computer representing types of fault conditions associated with different levels of attenuations; and

said evaluation instructions evaluating the level of signal change in association with said fault level data to determine type and cause information for the fault condition associated with said attenuation and transmitting the type of fault for display.

7. The system of claim 5 further comprising:

a set of distance data in communication with said system computer representing prescribed locations associated with corresponding distances in said distance data; and

said set of computer readable instructions include distance instructions for determining the distance of the fault based on the position of said attenuation on said scan, comparing the distance of the fault to said distance data, determining the prescribed location of the fault for display, and transmitting the prescribed location of the fault for display.

8. The system of claim 1 further comprising:

at least one sensor disposed along said fiber optic cable for detecting an intrusion along said fiber optic cable at prescribed locations and causing an attenuation in the scan signal representing the intrusion.

9. A computerized fiber optic security system including a fiber optic sensor line, a fiber optic scanning unit connected to one end of said sensor line for launching scan signals along the sensor line, and receiving return scan signals reflected back along the sensor line, and a system computer for receiving and analyzing said return scan signals to detect unauthorized activity in a secured area wherein said system comprises:

a computer readable medium;

a computer program residing on said computer readable medium including a set of computer readable instructions which include,

scanning instructions for transmitting light pulse scan signals outgoing along said sensor line;

receiving instructions for receiving said return scan signals at said scanning unit returning back along the same said sensor line,

baseline initialization instructions for establishing a baseline signal based on initial information from said scan signals and storing said baseline signal in said computer readable medium,

monitoring instructions monitoring said optical sensor line to receive said return scan signals in real-time representing the condition of said optical sensor line in real-time,

comparison instructions for determining if unauthorized activity has taken place based on a real-time comparison of said baseline signal and said return scan signals,

fault level evaluation instructions for evaluating said return scan signals upon determining an unauthorized activity has occurred to provide type and geographical location information for the activity, and

fault instructions for generating a real-time fault signal in response to determining the unauthorized activity has occurred.

10. The system of claim 9 wherein said set of computer readable instructions include audible output instructions for activating an associated audible output device in response to receiving said fault signal.

11. The system of claim 9 wherein said set of computer readable instructions include display instructions for visually indicating the occurrence of a fault on an associated display.

12. The system of claim 9 wherein said set of computer readable instructions include mapping instructions for mapping said fault signal on a visual representation of the fiber optic cable on the display whereby a specific location of the fault is indicated.

13. The system of claim 9wherein said comparison instructions include instructions for determining if said return scan signals contain attenuations, comparing said attenuations to said baseline signal, and transmitting a fault signal if said attenuations do not match said baseline signal.

14. The system of claim 13 further comprising:

a set of level data stored in a computer readable medium in communication with said computer readable medium representing types of faults associated with different levels of attenuations; and

said fault level evaluation instructions processing at least one attenuation from said return scan signal with said level data to determine the type of fault associated with said attenuation and transmitting the type of fault for display.

15. The system of claim 13 further comprising:

a set of location data stored in a computer readable medium in communication with said computer readable medium representing prescribed locations associated with corresponding distances;

said set of instructions including location instructions for determining the distance of the fault based on the position of said attenuation on said scan and determining the prescribed location of the fault based on a comparison of the distance of the fault and said set of location data.

16. A computerized method for detecting unauthorized activity in a protected area in real-time using a fiber optic cable as an optical sensor line, a optical fiber scanning unit connected to one end of said optical sensor line, and a remote computer operatively associated with said scanning unit, said method comprising:

scanning said optical sensor line by transmitting outgoing scan signals from said fiber scanning unit and obtaining return scan signals representing the real-time state of said sensor line reflected back along the same said optical sensor line to said scanning unit;

receiving said return scan signals from said scanning unit at said remote computer;

processing the return scan signals to determine an initial baseline signal representing the state of said sensor line in a normal, undisturbed state;

storing said initial baseline signal in a computer readable memory accessible by said remote computer;

continuously monitoring said optical sensor line using said return scan signals in real-time by said remote computer;

comparing said return scan signal to said baseline signal;

determining if a fault condition indicating unauthorized activity has occurred at a location along said sensor line based on an predetermined attenuation change in said return scan signal as compared to said baseline signal;

evaluating return scan signal upon occurrence of unauthorized activity to determine the fault condition and likely cause of the attenuation change;

generating a fault signal indicating that a fault correlated to said unauthorized activity has occurred based on said attenuation change; and

providing a warning of a fault in response to said fault signal.

17. The method of claim 16 further comprising activating an associated audible output device upon receiving said fault signal from said remote computer.

18. The method of claim 16 further comprising visually indicating the occurrence of a fault on an associated display screen upon receiving said fault signal.

19. The method of claim 18 further comprising mapping said fault signal on a visual representation of said fiber optic cable on said associated display.

20. The method of claim 16 further comprising determining the location and type of the fault that has occurred evaluating said return scan signal with a set of fault type data stored in computer readable memory representing different attenuations or spikes corresponding with different fault conditions.