Osamu Moriwaki

Novel PLC-based optical correlator for multiple phase-modulated labels

A correlation-based optical label processor is proposed that recognizes multiple phase-modulated labels. Noise is suppressed by employing a unique label format and differential receiving. The operating principle is confirmed experimentally by using a silica-based planar lightwave circuit.

Optical packet synchronizer using wavelength and space switching

The authors develop and demonstrate an optical packet synchronizer. Synchronization with a time resolution of 16 ns is achieved by selecting one of 64 optical paths, each with a different length, using wavelength and space switching based on a tunable distributed Bragg reflector laser diode and eight semiconductor optical amplifier gates per channel. Asynchronous optical packet signals are successfully aligned in a series of common time slots.

Performance analysis of variable optical delay circuit using highly nonlinear fiber parametric wavelength converters

The performance of a variable optical delay circuit that employs a fiber loop with highly nonlinear fiber parametric wavelength converters is discussed using both experiments and simulations. In our optical delay circuit, the delay time is determined from the number of circulations, which is controlled by the initially selected wavelength of the optical signal. We discuss the factors that limit the number of circulations described in our previous paper, derive the parameters that provide good performance levels, and confirm the performance by simulation. The simulated results indicate that 100 wavelength conversions can be achieved, namely, 100 different delay times can be given to optical packets.

Demonstration of an optical packet synchronizer for an optical packet switch

We have demonstrated a compact optical packet synchronizer. With a tunable DBR LD and SOA gates, the synchronization is successfully achieved with simple electric circuits by controlling the switching timing. Because OFCs are used, the OPSy is compact and the delay time can be controlled precisely. in this architecture, by increasing the number of wavelengths, finer resolution can be obtained without much increase in the losses and crosstalk.

AWG-Based Wavelength Router With Nonuniform Number of Transmission Paths

We have developed an arrayed-waveguide-grating (AWG)-based wavelength router with unequal transmission bandwidths for a system with nonuniformly distributed traffic. To realize the router, we designed the aperture width of the input-output waveguides at the border of the slab waveguide. We applied this AWG router to a physical star and logical full-mesh wavelength routing system, and we could create different numbers of paths between the nodes to correspond to the traffic demand

Loop-Back AWG Router With Nonuniform Transmission Capacity

We have developed an arrayed-waveguide-grating-based wavelength router with a loop-back structure for a system with nonuniformly distributed traffic. We describe the design principle with particular regard to the loop-back waveguide connections, and discuss its optical routing functions with some experimental results.

Integrated photonic decoder with complementary code processing and balanced detection for two-dimensional OCDMA

We propose a novel integrated-photonic decoder for two-dimensional (time/wavelength) OCDMA, which processes complementary codes and utilizes balanced detection to reduce unwanted cross-correlation interference. We successfully carried out a 10 Gbit/s transmission that demonstrated its effectiveness.