BER and Q factor evaluation of narrow-linewidth fiber ring laser

A C-band Erbium doped fiber laser is proposed and investigated. Using two sub-ring cavities and a saturable absorber, a high quality, stable and high optical signal to noise ratio operated fiber ring laser is obtained. Using different fiber Bragg gratings as wavelength filter, a narrow 3dB-bandwidth is necessary for the high quality operation. The fiber ring laser is evaluated in lightwave transmission. The Q factor and eye diagrams are also measured and discussed.