The polarization-scrambling technique could be used not only to suppress the polarization-induced detrimental effects in a long-haul lightwave system, but also to monitor various polarization-related parameters. However, this technique could interact with polarization-mode dispersion (PMD) and polarization-dependent loss, and then cause timing jitters, irregular intensity modulations, and PMD-induced repolarization. This problem could be substantially reduced by using the optimized scrambling frequency of about 10 kHz.
In amplified wavelength-division-multiplexed (WDM) networks, the performance of a low-frequency (<100 kHz) pilot-tone-based monitoring technique could be deteriorated by the slow dynamic properties of erbium-doped fiber amplifiers (EDFAs). We develop a simple model to describe this effect and estimate the maximum size of WDM network that the pilot-tone-based monitoring technique could support. The result shows that 100-kHz pilot tones could be used for the cost-effective monitoring of metro optical networks (32 channels, 320-km transmission).
We propose a control technique for erbium doped fiber amplifier (EDFA) gain transient occurring in optical burst network. In the optical burst network, optical packets are generated randomly and packet stream has idle time when no packet exists. This bursty nature of optical burst network causes gain transient in the EDFA with slow gain dynamics. To resolve this problem, the optical power of a channel delivering the burst control packets (BCPs) is modulated based on the information of the burst data (BD) packets contained in the BCP itself to feed constant power to the EDFA. We experimentally demonstrate 2.0-dB and 2.6-dB reductions in power fluctuation and gain transient in EDFA output, respectively. We show the stable transmission of 2.488 Gbit/s rate BCP and 9.953 Gbit/s rate BD packets using the proposed technique. The proposed method can be applied to optical burst switching (OBS) network which adopt out-of-band control channel covering small number of BD channels.
Conference Committee Involvement (2)
Optical Transmission, Switching, and Subsystems IV
5 September 2006 | Gwangju, South Korea
Optical Transmission, Switching, and Subsystems III