EA-transceiver for full-duplex WDM ring networks

A 1.55 μm waveguide electroabsorption (EA) modulator is presented as a full-duplex optical transceiver for wavelength division multiplex (WDM) optical networks. The modulation characteristics are experimentally analysed in terms of the extinction ratio and insertion loss while the detection properties are characterised by the responsivity. The 3 dB-bandwidth of the transceiver was found to be 17 GHz for modulation as well as for detection. The RF link gain of an optical access network incorporating the EA-transceiver was measured at microwave frequencies up to 15 GHz. The RF up- and downlink insertion losses at 0 dBm optical power are -27 dB and -34 dB, respectively. Furthermore, error-free full-duplex optical transmission of a 256 Mb/s PRBS (downlink) and a 56 Mb/s PRBS (uplink) is demonstrated and a practical architecture of an optical ring network is proposed in which the EA-transceiver is employed in a transparent and full-duplex base station