Nonsplit dual-stage EDFA operating in the C- plus L-band

Abstract

The feasibility of a dual-stage erbium-doped fiber amplifier (EDFA) design for operation in both the C-band and the L-band is studied. The design is comprised of nonsplit single-pass amplification at both bands, thus eliminating the need for band multiplexing and demultiplexing in an individual band-amplification design. The results show that the amplifier provides continuous homogeneous gain ranging from 1530 to 1605 nm with an average gain of 19.7 dB at -30-dBm input signal power. A minimum gain variation of 9.5 dB was achieved for this entire range, which includes the standard 1530-nm-region gain peak in a silica-based EDF and without the assistance of any gain-flattening devices. The noise figure was below 7.4 dB for the entire C- plus L-band region for a minimum of 5.3 dB at 1570 nm, with signal power of -30 dBm. This C- plus L-band EDFA provides an average output power of 6.1 dBm at -10 dBm input signal power.