Novel architecture of wavelength interleaving filter with Fourier transform-based MZIs

A novel wavelength interleaving filter (interleaver) has been demonstrated with Fourier transform-based Mach Zehnder interferometers (MZIs). The interleaver works as two independent 1/spl times/2 interleavers by sharing their delay lines and couplers.

1. Introduction

A density of channels as well as a bit-rate per channel in Dense-Wavelength Division Multiplexing (D-WDM) systems has been higher and higher to accommodate exploded traffic demand, which sets too 'demanding performance to optical components. In order to improve such a situation, interleave-filtering technique, which separates the incoming spectrum into two complementary sets of periodic spectra, has been viewed with keen interest. The several types of interleaving filters (interleavers) have been proposed. Using the technique combined with a conventional MUX/DEMUX such as arrayed waveguide gratings (AWGs) or 'thin film filters (TFFs), D-WDM systems could be easily and flexibly upconverted.