| 摘要 |
PCT No. PCT/GB93/00247 Sec. 371 Date Sep. 9, 1994 Sec. 102(e) Date Sep. 9, 1994 PCT Filed Feb. 5, 1993 PCT Pub. No. WO93/16533 PCT Pub. Date Aug. 19, 1993.Fault location in an optical signal transmission network in which a main optical fibre is divided into a plurality of branch circuits, is simplified. Optical time domain reflectrometry (OTDR) equipment transmits an output signal along the main fibre, and for each branch circuit the signal is caused to be returned to the OTDR equipment from the branch to be modified in a manner unique to that branch. |
