Wolfgang Schairer

160 Gb/s OTDM networking using deployed fiber

This paper reports a 160-Gb/s OTDM network comprising switching and demultiplexing through field deployed fiber. The 160-Gb/s signal was obtained by time-interleaving 16 channels of a 10-Gb/s signal. The add-drop node was realized by using a gain-transparent operation of a semiconductor optical amplifier (SOA). A subharmonic clock recovery with a prescaled electrooptical phase locked loop employing an electroabsorption modulator was applied. An OTDM receiver employed a four-wave mixing principle in an SOA. The impact of fiber chromatic and polarization-mode dispersion (PMD) is discussed. Switching and demultiplexing performance are shown for a fiber link of 275 and 550 km, respectively. Excellent operation of clock recovery, drop-through-add function, and transmission was achieved.

Interchannel nonlinear transmission penalties in polarization-multiplexed 2 x 10 Gbit/s differential phase-shift keying transmission

We discuss the performance of a multichannel 2×10Gbit?s polarization-multiplexed differential phase-shift keying transmission system. Through simulations and transmission experiments we find that, despite the constant power envelope of non-return-to-zero phase-shift keying modulation formats, polarization multiplexing strongly reduces the nonlinear tolerance and transmission performance at a 2×10Gbit?s line rate with multichannel transmission. This results in a 10 dB power penalty when comparing single- and nine-channel transmission. Additionally, multichannel impairments in differential phase-shift keying and on–off keying are compared for 2×10Gbit?s polarization-multiplexed transmission.

Equalisation of Fibre Bragg Gratings' Group Delay Ripple by means of Maximum Likelihood Sequence Estimation

Fibre Bragg Gratings are a promising technology for dispersion compensation in optical links, but suffer from group delay ripple (GDR) induced penalties. We identify maximum likelihood sequence estimation (MLSE) as an efficient technique for GDR equalization

Toward high-speed optical networks of the future: an overview of 160 Gbit/s transmission and networking

An overview of a wide choice of current technologies and components suitable for the use of 160 Gbit/s optical time domain multiplexing (OTDM) systems is given. A selection of the presented components were used to implement a 160 Gbit/s network. In a field trial on BT’s network we demonstrated transmission over 550 km and a fully operating OTDM network including a time domain add-drop multiplexer (TD-OADM) at a data rate of 160 Gbit/s at a single wavelength and a tributary data rate of 10 Gbit/s.