From the Publisher:
A Unique, Cutting-Edge Approach to Optical Filter Design With more and more information being transmitted over fiber-optic lines, optical filtering has become crucial to the advanced functionality of todays communications networks. Helping researchers and engineers keep pace with this rapidly evolving technology, this book presents digital processing techniques for optical filter design. This higher-level approach focuses on filter characteristics and enables readers to quickly calculate the filter response as well as tackle larger and more complex filters. The authors incorporate numerous theoretical and experimental results from the literature and discuss applications to a variety of systemsincluding the new wavelength division multiplexing (WDM) technology, which is fast becoming the preferred method for system upgrade and expansion. Special features of this book include:
*The theory underlying various architectures that can approximate any filter function
*Filter design techniques applicable to a broad range of materials systemsfrom silica to fiber to microelectromechanical (MEM) systems
*Design examples relevant to filters for WDM systems and planar waveguide devices
*250 figures as well as problem sets for use in graduate-level studies

Optical Filter Design and Analysis: A Signal Processing Approach

Silica-based planar lightwave circuits (PLC) provide various important devices for both optical wavelength-division-multiplexing networks and optical access network. This paper is an overview of recent progress in PLC technology including optical power splitters, arrayed-waveguide gratings, thermooptic switches, and hybrid integrated PLC's.

Silica-based planar lightwave circuits

Recent progress in optical time-division-multiplexed (TDM) transmission technologies is reviewed including optical short pulse generation, time-division multiplexing/demultiplexing, timing extraction, and waveform measurement. The latest 400-Gbit/s transmission experiments based on optical signal processing are presented and the possibility of terabit/second TDM transmission is discussed.

Ultrahigh-speed optical time-division-multiplexed transmission technology based on optical signal processing

Silica-based planar lightwave circuits (PLCs) are playing key roles in both optical dense wavelength-division multiplexing networks and optical access networks. This paper provides an outline of PLC technology focusing on passive devices such as arrayed waveguide grating multiplexers.

Silica-based planar lightwave circuits: passive and thermally active devices

We propose using a novel multifunction optical filter with a Michelson–Gires–Tournois interferometer (MGTI) for future smart wavelength-division-multiplexed network system applications. The MGTI filter is a typical Michelson interferometer in which one of its reflecting mirrors is replaced with a Gires–Tournois resonator. One unique feature of this device is that it can function as a channel-passing (CP), a channel-dropping (CD), or a wide-bandpass (BP) filter, depending on the interferometer arm-length difference. Other interesting features are that (1) the linewidths of both the CP and the CD filter are twice as narrow as that of a typical Fabry–Perot filter with similar parameters, (2) theoretical visibility is always unity regardless of the mirror reflectance value, and (3) the BP filter has an excellent boxlike response function. Numerical results showing these characteristics are presented.

Multifunction optical filter with a Michelson-Gires-Tournois interferometer for wavelength-division-multiplexed network system applications.

The authors report, in detail, an integrated-optic variable group-delay dispersion equalizer based on a lattice-form programmable optical filter. The variable dispersion equalizer consists of an alternating cascade of symmetrical and asymmetrical Mach-Zehnder interferometers. An equalizer with nine symmetrical and eight asymmetrical interferometers is fabricated on a planar lightwave circuit and its dispersion varied step by step from -681 to +786 ps/nm in the operational frequency range of 16.3 GHz. The effectiveness of the equalizer is shown by compensating the dispersion of three different fibers with a single equalizer. The performance of the equalizer is also evaluated and examined by numerical investigations.

Variable group-delay dispersion equalizer using lattice-form programmable optical filter on planar lightwave circuit

The authors report the first realisation of an integrated-optic variable group-delay dispersion equaliser using a lattice-form programmable optical filter. The equaliser consists of seven tunable couplers and six asymmetrical Mach-Zehnder interferometers cascaded alternately in series. The dispersion can be varied step by step from -923 ps/nm to +653 ps/nm.

Variable group-delay dispersion equaliser based on a lattice-form programmable optical filter

The higher order (third order) dispersion of dispersion shifted fibre has been successfully compensated by using a lattice-form programmable filter fabricated on a planar lightwave circuit. The equaliser offers a dispersion slope of -15.8 ps/nm/sup 2/ over 170 GHz in the 1.55 /spl mu/m region. The effectiveness of the equaliser has been confirmed by the pulse transmission experiment in which the trailing ripples of pulses caused by the higher order dispersion of 300 km dispersion shifted fibre have been eliminated.

Higher order dispersion equaliser of dispersion shifted fibre using a lattice-form programmable optical filter

The effectiveness of a variable group-delay dispersion equaliser in compensating for the dispersions of various lengths of fibre is explained The variable dispersion equaliser has a lattice-form programmable optical filter configuration and its dispersion can be varied from -681 to 786 ps/nm The dispersion of three different fibres has been compensated for with a single equaliser

Dispersion compensation using a variable group-delay dispersion equaliser

The authors report 200 Gbit/s, 100 km time-division-multiplexed transmission with 2 ps signal pulses using a dispersion slope equaliser on a planar lightwave circuit. The pulse distortion caused by the dispersion slope is almost completely recovered, and the power penalty is improved by > 4 dB by the equaliser.

K. Jinguji

Papers

Variable group-delay dispersion equalizer using lattice-form programmable optical filter on planar lightwave circuit

Variable group-delay dispersion equaliser based on a lattice-form programmable optical filter

Higher order dispersion equaliser of dispersion shifted fibre using a lattice-form programmable optical filter

Dispersion compensation using a variable group-delay dispersion equaliser

Dispersion slope equalising experiment using planar lightwave circuit for 200 Gbit/s time-division-multiplexed transmission