Noise improved pulsed OTDR

摘要: A method of pulsed OTDR (optical time domain reflectometry) measurement, wherein single test signals (1) are sent into an optical fiber (2) with light source, is characterized in that the modulated during their duration. The inventive results a low level electrical noise on backscattered signal, even if narrowband source used embedded system. A pulse generator (31) generates separate rectangular (32),whereas dummy data (33) provides continuously signal (34). An AND-gate (35) multiplies (32,34) and generated laser drive (36) fed DFB (37).