Iterative algorithm for rapid fault isolation
Methods, systems, and apparatus for detecting fault are disclosed. In one aspect, a signal having an initial pulse width is transmitted on a telecommunication line. A fault location index is identified based on at least one fluctuating echo tap of the signal. An updated pulse width is determined based on the initial pulse width and the fault location index. The fault location index is updated based on at least one fluctuating echo tap of an updated signal having the updated pulse width.
1. A method, comprising:
transmitting, on a telecommunication line, a first pulse amplitude communication signal having an initial pulse width; and
after transmitting the first pulse amplitude communication signal on the telecommunication line:
identifying a first fault location index based on an echo of the first pulse amplitude communication signal, wherein the first fault location index represents a location of a fault on the telecommunications line;
determining an updated pulse amplitude communication signal having an updated pulse width based on the initial pulse width and the identified first fault location index;
transmitting, on the telecommunication line, a second pulse amplitude communication signal having the updated pulse width; and
identifying a second fault location index based on at least one fluctuating echo of the second pulse amplitude communication signal having the updated pulse width, wherein the second fault location index represents an updated location of the fault on the telecommunications line.
2. The method of claim 1 , wherein the first fault location index is identified based on a fluctuating echo of the first pulse amplitude communication signal.
3. The method of claim 1 , wherein determining the updated pulse width comprises determining the updated pulse width based on at least one inequality relationship of the first fault location index and the initial pulse width.
4. The method of claim 3 , wherein the at least one inequality relationship comprises:
( N k+1 +I )×Δ K+1 >( N k −½)×Δ K ; and
( N k+1 +I+ 1)×Δ K+1 <( N k +½)×Δ K,
wherein N k is the first fault location index, N k+1 is the second fault location index, Δ K is the initial pulse width, Δ K+1 is the updated pulse width, and I is an integer.
5. The method of claim 4 , wherein I is set to 0.
6. The method of claim 1 , further comprising:
identifying a supplemental fault location index based on at least one supplemental fluctuating echo from the first pulse amplitude communication signal; and
determining the updated pulse width based on the initial pulse width, the identified first fault location index, and the identified supplemental fault location index.
7. The method of claim 1 , wherein identifying a second fault location index comprises repeating the transmitting, the identifying, and the determining until one or more completion criteria are met.
8. The method of claim 7 , wherein the one or more completion criteria comprise the updated pulse width being less than a predetermined pulse width.
9. The method of claim 1 , wherein the first pulse amplitude communication signal is a variable data rate signal.
10. The method of claim 1 , wherein the telecommunication line comprises a band-limited channel, and a Signal to Noise Ratio (SNR) of the first pulse amplitude communication signal is used in determining the updated pulse width.
11. The method of claim 10 , wherein determining an updated pulse width comprises reducing the updated pulse width if the SNR is higher than a predetermined threshold.
12. The method of claim 10 , wherein determining an updated pulse width comprises increasing the updated pulse width if the SNR is lower than a predetermined threshold.
13. A system, comprising:
a variable pulse width transmitter configured to transmit signals on a telecommunication line; and
one or more processors that interact with the variable pulse width transmitter and are configured to:
cause the variable pulse width transmitter to transmit a first pulse amplitude communication signal having an initial pulse width; and
after causing the variable pulse width transmitter to transmit the first pulse amplitude communication signal on the telecommunication line:
identify a first fault location index based on at least one fluctuating echo of the first pulse amplitude communication signal, wherein the first fault location index represents a location of a fault on the telecommunications line;
determine an updated pulse amplitude communication signal having an updated pulse width based on the initial pulse width and the identified first fault location index;
cause the variable pulse width transmitter to transmit a second pulse amplitude communication signal having the updated pulse width on the telecommunication line; and
identify a second fault location index based on at least one fluctuating echo of the second pulse amplitude communication signal having the updated pulse width, wherein the second fault location index represents an updated location of the fault on the telecommunications line.
14. The system of claim 13 , wherein determining the updated pulse width comprises determining the updated pulse width based on at least one inequality relationship of the first fault location index and the initial pulse width.
15. The system of claim 14 , wherein the at least one inequality relationship comprises:
( N k+1 +I )×Δ K+1 >( N k −½)×Δ K ; and
( N k+1 +I+ 1)×Δ K+1 <( N k +½)×Δ K,
wherein N k is the first fault location index, N k+1 is the second fault location index, Δ K is the initial pulse width, Δ K+1 is the updated pulse width, and I is an integer.
16. The system of claim 15 , wherein the integer I is set to 0.
17. The system of claim 13 , wherein the one or more processors further configured to:
identify a supplemental fault location index based on at least one supplemental fluctuating echo from the first pulse amplitude communication signal; and
determine an updated pulse width based on the initial pulse width, the identified first fault location index, and the identified supplemental fault location index.
18. The system of claim 13 , wherein identifying a second fault location index comprises repeating the causing, the identifying, and the determining until one or more completion criteria are met.
19. The system of claim 18 , wherein the one or more completion criteria comprise the updated pulse width being less than a predetermined pulse width.
20. The system of claim 13 , wherein the first pulse amplitude communication signal is a variable data rate signal.
21. An apparatus comprising instructions embodied on a tangible, non-transitory computer-readable medium, the instructions operable when executed to cause the apparatus to perform operations comprising:
transmitting, on a telecommunication line, a first pulse amplitude communication signal having an initial pulse width; and
after transmitting the first pulse amplitude communication signal on the telecommunication line:
identifying a first fault location index based on at least one fluctuating echo of the first pulse amplitude communication signal, wherein the first fault location index represents a location of a fault on the telecommunications line;
determining an updated pulse amplitude communication signal having an updated pulse width based on the initial pulse width and the identified first fault location index;
transmitting, on the telecommunication line, a second pulse amplitude communication signal having the updated pulse width; and
identifying a second fault location index based on at least one fluctuating echo of the second pulse amplitude communication signal having the updated pulse width, wherein the second fault location index represents an updated location of the fault on the telecommunications line.
22. The apparatus of claim 21 , wherein determining the updated pulse width comprises determining the updated pulse width based on at least one inequality relationship of the first fault location index and the initial pulse width.
23. The apparatus of claim 22 , wherein the at least one inequality relationship comprises:
( N k+1 +I )×Δ K+1 >( N k −½)×Δ K ; and
( N k+1 +I+ 1)×Δ K+1 <( N k +½)×Δ K,
wherein N k is the first fault location index, N k+1 is the second fault location index, Δ K is the initial pulse width, Δ K+1 is the updated pulse width, and I is an integer.
24. The apparatus of claim 23 , wherein the integer I is set to 0.
25. The apparatus of claim 21 , wherein the operations further comprise:
identifying a supplemental fault location index based on at least one supplemental fluctuating echo from the first pulse amplitude communication signal; and
determining the updated pulse width based on the initial pulse width, the identified first fault location index, and the identified supplemental fault location index.
26. The apparatus of claim 21 , wherein identifying a second fault location index comprises repeating the transmitting, the identifying, and the determining until one or more completion criteria are met.
27. The apparatus of claim 26 , wherein the one or more completion criteria comprise the updated pulse width being less than a predetermined pulse width.
28. The apparatus of claim 21 , wherein the first pulse amplitude communication signal is a variable data rate signal.