12 dB of noise reduction by a NOLM based all optical all passive regenerator

In this paper, an asymmetric nonlinear optical loop mirrors (NOLM) was used to analyse optimum splitting ratio for erbium doped optical fibre amplifier (EDFA) noise reduction. To measure the noise reduction of the NOLM, we compare the noise power at the NOLM output with the noise power at the EDFA output, acting as a reference level. This 12 dB of noise reduction is the best result experimentally achieved with an asymmetric NOLM. It is concluded that the setup shown becomes attractive for commercial optical telecommunication systems with pulse durations longer than 1.3 ps.