An optical communications repeater is used in a fiber-optic communications system to regenerate an optical signal by converting it to an electrical signal, processing that electrical signal and then retransmitting an optical signal. Such repeaters are used to extend the reach of optical communications links by overcoming loss due to attenuation of the optical fibre and distortion of the optical signal. Such repeaters are known as 'optical-electrical-optical' (OEO) due to the conversion of the signal. Repeaters are also called regenerators for the same reason.
Classification of regenerators
Optical regenerations are classified into 3 categories by the 3 R's scheme .
1.R : reamplification of the data pulse alone is carried out.
2.2R : in addition to reamplification, pulse reshaping is carried out. Eg: Mamyshev 2R regenerator
3.3R : in addition to reamplification and reshaping, retiming of data pulse is done.
September 13, 2011