System and method for monitoring an optical communication system
First Claim
1. A method of monitoring an optical communication system using differential optical time domain reflectometry (OTDR), said optical communication system including first and second optical paths, said first and second optical paths being coupled together, said method comprising:
- optically loading at least said first optical path;
transmitting a first OTDR test signal on said first optical path at a first test wavelength;
transmitting a second OTDR test signal on said first optical path at a second test wavelength;
detecting first and second reflected OTDR signals on said second optical path to produce first and second sets of OTDR test data, said first and second reflected OTDR signals corresponding to said first and second OTDR test signals being reflected from at least one reflecting element in said first optical path;
determining a difference between said first and second sets of OTDR test data to produce difference data representing gain tilt in at least one of said optical paths; and
monitoring a condition of said at least one of said optical paths using said difference data.
6 Assignments
0 Petitions
Accused Products
Abstract
A monitoring system and method may be used to monitor an optical communication system. A monitoring system and method may be used to derive loop gain data sets from optical time domain reflectometry (OTDR) or coherent optical time domain reflectometry (COTDR) data. A monitoring system and method may also use differential monitoring techniques to obtain data representing gain tilt in the transmission system and to locate an anomalous loss or gain in the transmission system.
145 Citations
24 Claims
-
1. A method of monitoring an optical communication system using differential optical time domain reflectometry (OTDR), said optical communication system including first and second optical paths, said first and second optical paths being coupled together, said method comprising:
-
optically loading at least said first optical path; transmitting a first OTDR test signal on said first optical path at a first test wavelength; transmitting a second OTDR test signal on said first optical path at a second test wavelength; detecting first and second reflected OTDR signals on said second optical path to produce first and second sets of OTDR test data, said first and second reflected OTDR signals corresponding to said first and second OTDR test signals being reflected from at least one reflecting element in said first optical path; determining a difference between said first and second sets of OTDR test data to produce difference data representing gain tilt in at least one of said optical paths; and monitoring a condition of said at least one of said optical paths using said difference data. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method of monitoring an optical communication system using differential coherent optical time domain reflectometry (COTDR), said optical communication system including first and second optical paths being coupled together, said method comprising:
-
optically loading at least said first optical path using multiple loading tones at different loading wavelengths; transmitting a first COTDR test signal on said first optical path at a first test wavelength; transmitting a second COTDR test signal on said first optical path at a second test wavelength; detecting first and second reflected COTDR signals on said second optical path to produce first and second sets of COTDR test data, and said first and second reflected COTDR signals corresponding to said first and second COTDR test signals being reflected from at least one reflecting element in said first optical path; determining a difference between said first and second sets of COTDR test data to produce difference data representing gain tilt in at least one of said optical paths; and monitoring a condition of said at least one of said optical paths using said difference data. - View Dependent Claims (12, 13)
-
-
14. A method of monitoring an optical communication system using differential coherent optical time domain reflectometry (COTDR), said optical communication system including first and second optical paths being coupled together, said method comprising:
-
optically loading at least said first optical path using a loading tone at a first loading wavelength; optically loading at least said first optical path using a loading tone at a second loading wavelength; transmitting a COTDR test signal on said first optical path at a single test wavelength; detecting a first reflected COTDR test signal on said second optical path when using said loading tone at said first loading wavelength to produce a first set of COTDR test data, said first reflected COTDR signal corresponding to said first COTDR test signal being reflected from at least one reflecting element in said first optical path; detecting a second reflected COTDR test signal on said second optical path when using said loading tone at said second loading wavelength to produce a second set of COTDR test data, said second reflected COTDR signal corresponding to said second COTDR test signal being reflected from at least one reflecting element in said second optical path; and determining a difference between said first and second sets of COTDR test data to produce difference data representing gain tilt in at least one of said optical paths; and monitoring a condition of said at least one of said optical paths using said difference data. - View Dependent Claims (15)
-
-
16. A method of monitoring an optical communication system including first and second optical paths, said first and second optical paths being coupled together, said method comprising:
-
optically loading at least said first optical path; transmitting a first test signal on said first optical path at a first test wavelength; transmitting a second test signal on said first optical path at a second test wavelength; optically loading said second optical path using at least one loading tone, wherein said loading tone has a wavelength at or near said first test wavelength when detecting said first test signal, and wherein said loading tone has a wavelength at or near said second test wavelength when detecting said second test signal; detecting said first and second test signals on said second optical path to produce first and second sets of test data; and determining a difference between said first and second sets of test data to produce difference data representing gain tilt in at least one of said optical paths; and monitoring a condition of said at least one of said optical paths using said difference data. - View Dependent Claims (17, 18)
-
-
19. A system comprising:
-
first and second optical paths configured to transmit optical signals in opposite directions; at least one coupling path coupling said first optical path to said second optical path; at least one optical load for optically loading at least said first optical path; and monitoring equipment configured to transmit first and second OTDR test signals on said first optical path at first and second test wavelengths, to detect first and second reflected OTDR test signals to obtain first and second OTDR data sets, and to determine a difference between said OTDR data sets to produce difference data representing gain tilt in at least one of said optical paths. - View Dependent Claims (20, 21, 22, 23, 24)
-
Specification