  This paper presents a theoretical and experimental investigation of optical
signal regeneration properties of a non-linear optical loop mirror using a
semiconductor optical amplifier as the active element (SOA-NOLM). While this
device has been extensively studied for optical time division demultiplexing
(OTDM) and wavelength conversion applications, our proposed approach, based on
a reflective configuration, has not yet been investigated, particularly in the
light of signal regeneration. The impact on the transfer function shape of
different parameters, like SOA position in the interferometer and SOA input
optical powers, are numerically studied to appreciate the regenerative
capabilities of the device.Regenerative performances in association with a dual
stage of SOA to create a 3R regenerator which preserves the data polarity and
the wavelength are experimentally assessed. Thanks to this complete
regenerative function, a 100.000 km error free transmission has experimentally
been achieved at 10 Gb/s in a recirculating loop. The evolution of Bit Error
Rate for multiple pass into the regenerator and the polarization insensitivity
demonstration to input data are presented.
