High sensitivity direct detection using a packaged erbium-doped fibre preamplifier incorporating an autolocking optical filter

The use of erbium-doped fibre amplifiers (EDFA) as power and pre-amplifiers in point-to-point repeaterless communication systems has attracted much attention. The authors describe an EDFA configuration that has been optimised for high sensitivity preamplified receiver applications. Experimental results at 600 Mbit/s and 2.4 Gbit/s from both the laboratory and field are compared with theoretically predicted sensitivities and the penalties identified and discussed