SYSTEM AND METHOD FOR DETECTING DETERIORATION OR A CUT IN A CABLE FOR CONVEYING SIGNALS

• US 20140303906A1
• Filed: 03/22/2012
• Published: 10/09/2014
• Est. Priority Date: 03/31/2011
• Status: Abandoned Application

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Charlot, Bernard
• Application Number:
  US14/008,534
• Publication Number:
  US 20140303906A1
• Time in Patent Office: Days
• US Class Current: 702/36
• CPC Class Codes: G01M 11/33 with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
• CPC Class Codes: G01N 2021/9511 Optical elements other than lenses, e.g. mirrors testing of optical apparatus in G01M11/00
• CPC Class Codes: G01R 31/08 Locating faults in cables, transmission lines, or networks
• CPC Class Codes: G01R 31/083 in cables, e.g. underground
• CPC Class Codes: G01R 31/088 Aspects of digital computing

Abstract

A system and a method for detecting deterioration of or cuts in a cable for transmitting signals, includes at least at a first end of the cable a transceiver, at least at a second end of the cable a transceiver, and means for synchronization of the signals transmitted by the transceivers, and the system further includes at least processing means adapted to determine the times of non-reception of the signal at each end of said cable.

Claims

1. A system for detecting deterioration of or cuts C in a cable for transmitting signals between at least one first device A and at least one second device B, comprising:

said first device A being disposed at a first end of the cable and including at least a transceiver, synchronization means, means for communication between the first device A and the second device B, calculation means connected to the transceiver, the transmitter being adapted to transmit a signal S_A from A to B, the receiver being adapted to measure times of non-reception of a signal,

said second device B being disposed at a second end of the cable, said second device B including at least the following components;

a transceiver, synchronization means, means for communication between A and B, calculation means connected to the transceiver, the transmitter being adapted to transmit a signal S_B from B to A, the receiver being adapted to measure times of non-reception of a signal, and

wherein the means for communicating times of non-reception of the signals measured at the receivers are adapted to transfer the measured time of non-reception of the signal S_B at the first device A and the measured time of non-reception of the signal S_A at the second device B to said calculation means, said calculation means being adapted to determine the time t_C and the location X_C of the fault or the cut in the cable from the measured times of non-reception of signals received at the calculation means.

2. The system as claimed in claim 1, wherein the means for calculation of non-reception of the signal are adapted to execute at least the following steps:

X_A is the curvilinear abscissa of A as measured along the cable, X_B is the curvilinear abscissa of B along the cable, considering a direction of increasing abscissa from B to A,

V is the average speed of propagation of a signal in the cable between A and B, considered constant or substantially constant,

X_C is the curvilinear abscissa of the point of deterioration or the cut C in the cable and t_C is the cut time,

tr_B is the time of non-reception of the signal measured by the receiver B on the signal S_A and tr_A is the time of non-reception of the signal measured by the receiver A on the signal S_B

the location X_C of the cut C in the cable is given by;

X_C=(X_A+X_B)/2+V·

(tr_B−

tr_A)

and the cut time t_C is given by;

t_C=(tr_A+tr_B)/2+(X_B−

X_A)/2V.

3. The system as claimed in claim 1, wherein the signals S_A, S_B transmitted by A and B are CDMA signals.

4. The system as claimed in claim 1, wherein the cable is a copper cable.

5. The system as claimed in claim 1, wherein the cable is an optical fiber and the signals transmitted to detect deterioration or cutting are optical signals.

6. The system as claimed in claim 1, wherein the means for communication between the first device A and the second device B consist of a wireless telephone.

7. The system as claimed in claim 1, wherein the synchronization means include a GPS receiver.

8. A method for detecting deterioration of or cuts C in a cable for transmitting signals, the method being employed in the system as claimed in claim 1, further comprising:

Transmitting simultaneously at least one first signal S_A from a first device A to a second device B and at least one second signal S_B from the second device B to the first device A, transmission being synchronized,

Detecting the time at which there is absence of reception of the signal S_A at the receiver of B and absence of reception of the signal S_B at the receiver of A,

Determining from tr_A the time of disappearance or non-reception of the signal measured by the receiver of A and from tr_B the time of disappearance or non-reception of the signal measured by the receiver of B, the location X_C and the time t_C of the cut in or the deterioration of the cable.

9. The method as claimed in claim 8, wherein the time tr_A of disappearance of the signal measured by the receiver A and the time tr_B of disappearance of the signal measured by the receiver B are measured using a threshold level value S below which the signals are no longer detectable.

10. The method as claimed in claim 8 further comprising:

X_A is the curvilinear abscissa of A as measured along the cable, X_B is the curvilinear abscissa of B along the cable, considering a direction of increasing abscissa from B to A,

V is the average speed of propagation of a signal in the cable between A and B, considered constant or substantially constant,

X_C is the curvilinear abscissa of the point of deterioration or the cut C in the cable and t_C is the cut time,

tr_B is the time of disappearance of the signal measured by the receiver of B on the signal S_A and tr_A is the time of disappearance of the signal measured by the receiver of A on the signal S_B

the location X_C of the cut C in the cable is given by;

X_C=(X_A+X_B)/2+V·

(tr_B−

tr_A)

and the cut time t_C is given by;

t_C=(tr_A+tr_B)/2+(X_B−

X_A)/2V.

11. The method as claimed in claim 8, wherein CDMA signals are used and the last symbols respectively received by at least the first device A and at least the second device B are detected to determine the area of the cut in or the deterioration of the cable.

12. The use of the system as claimed in claim 1 to detect cuts in or deterioration of copper cable.