Abstract
This paper proposes a new upgrading method of the existing passive optical network (PON) by hybrid amplification, which uses a distributed Raman amplifier (DRA), a lumped Raman amplifier (LRA) and Er-doped fiber amplifier (EDFA). Properties of hybrid amplification determine the realization of the proposed upgrading method. For estimating the gain and OSNR (optical signal noise ratio) of EDFA with 980 and 1480nm pumping, we have developed new equations. Calculated gain and OSNR values of EDFA and LRA are compared with experimental results and they show in good agreement.