| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for measuring optical path delay on duplex optical lines, the method being able to measure delay difference between duplex optical lines of an active optical line and a bypass optical line even if a communication load between transmission devices is small, and to provide a measuring device thereof.SOLUTION: By using an optical signal (having randomness) transmitted by an ONU as test light, a signal processing and result display unit measures delay difference from accordance of similarity (correlation) of a pulse string of a random pulse signal. The signal processing and result display unit detects a position of data signal from signal patterns 21 of active and bypass optical lines, divides an active optical line signal pattern into multiple classes, and calculates a value 22 of square of the average in each class. Then, the signal processing and result display unit calculates a mutual correlation function from the value 22 of square of the average in each class, and measures a delay time that makes the calculation value the largest. |
