Self-detecting optical-time-domain reflectometer for single-mode fibers.
A new type of optical-time-domain reflectometer (OTDR) has been demonstrated. It uses a semiconductor laser diode (LD) as both a pulse emitter and a photodetector. With a LD operating at 1.31 microm, a fault-location length for a single-mode optical fiber of about 20 km has been achieved by extrapolating the log-transformed OTDR slope to the background-noise level. This length has been extended to 25 km at a wavelength of 1.56 microm. Wavelength and polarization dependences of the LD's as photodetectors were also investigated. No polarization dependence was observed.
Nakazawa
M
M
Nakashima
T
T
Seikai
S
S
Ikeda
M
M