W. Chujo

Multi-hop, 40 Gbit/s variable length photonic packet routing based on multi-wavelength label switching, waveband routing and label swapping

Three-hop, 40 Gbit/s, variable length all-optical packet routing with over 120 km transmission based on multi-wavelength label switching, waveband routing (label merge), and all-optical label swapping has been demonstrated experimentally for the first time. The details are expressed in the presentation.

1.28 Tbit/s (160 Gbit/s/spl times/8 wavelengths) throughput variable length packet switching using optical code based label switch

A novel ultra-high speed (over 160 Gbit/s), large throughput (over 1 Tbit/s), variable-length optical packet switching system, based on all-optical parallel table lookup for all the packets with different wavelength by an optical transparent label processor, is proposed. 1.28 Tbit/s optical packet switching with 120 km transmission is demonstrated.

Spectral domain interferometry for OCDR using non-Gaussian broad-band sources

A static Michelson interferometer coupled with optical spectral analysis has been used to perform optical coherence-domain reflectometry (OCDR). Compensation of both the coherence sidelobes caused by a non-Gaussian source spectrum and the coherence broadening caused by dispersion is shown. Reflections indistinguishable using an EDFA source and conventional scanning OCDR are clearly distinguished with this method.

1.6 bit/s/Hz, 6.4 Tbit/s OCDM/WDM (4 OCDM /spl times/ 40 WDM /spl times/ 40 Gbit/s) transmission experiment

We demonstrate the transmission of 6.4 Tbit/s OCDM/WDM (4 OCDM /spl times/ 40 WDM /spl times/ 40 Gbit/s) using, only the C-band wavelength region. A record of 1.6 bit/s/Hz spectrum efficiency is achieved by QPSK optical encoding/decoding along with optical time-gating and optical thresholding in addition to polarization multiplexing.

Direct detection of OC-192 DPSK signal using polarization-controlled differential-phase-to-intensity conversion (DPIC)

The differential-phase-to-intensity conversion (DPIC) can be used to detect an optical phase-shift of laser light. The system is based on injection locking of a semiconductor laser. We have now found the waveform of a DPIC signal can be adjusted by controlling and selecting the polarization of the lightwaves before and after the slave laser. We experimentally investigated the phenomenon, and concluded that it originated in TM-mode excitation and interference between the TE and TM modes within and after the slave laser. Such adjustment of the waveform according to the condition of polarization is useful because it can achieve direct demodulation of an optical DPSK signal without using an electrical circuit. The adoption of the DPSK signal format enables a higher bit rate than the original DPIC scheme. We demonstrated direct detection of an OC-192 (9.95328 Gb/s) DPSK signal by using polarization-controlled DPIC.

Synchronous optical demultiplexing and sampling of 80-Gb/s OTDM signals by optically recovered clock using mode-locked laser diode and symmetric Mach-Zehnder switch

A demonstration of optical demultiplexing of an 80-Gb/s signal through a fiber transmission line by using an injection mode-locked laser diode (LD) to perform all-optical subharmonic clock recovery to control a symmetric Mach-Zehnder demultiplexer is described. Moreover, simultaneous optical sampling by the recovered clock was also demonstrated.

80G to 10G bit/s variable rate photonic packet routing based on multi-wavelength label switch

A novel ultra-high speed variable data rate photonic packet routing network based on multi-wavelength label switch is proposed. 80 Gbit/s to 10 Gbit/s variable data rate photonic packet routing with all-optical label recognition using multi-section fiber Bragg gratings is demonstrated experimentally for the first time.

Simultaneously generated 3.24 Tbit/s (81 WDM /spl times/ 40 Gbit/s) carrier suppressed RZ transmission using a single supercontinuum source

A 3.24 Tbit/s (81 WDM /spl times/ 40 Gbit/s) carrier suppressed RZ (CS-RZ) format is simultaneously generated using a single supercontinuum source pumped by optically multiplexed 40 Gbit/s CS-RZ and is transmitted over an 80 km link.

Suppression of PMD induced pulse broadening by using nonlinear evolution of polarization mode-coupling

We have experimentally investigated the nonlinear evolution of the basic polarization parameters. The nonlinear suppression of PMD (polarization mode dispersion) induced pulse broadening by reducing the coupling of the polarization modes is experimentally demonstrated in 10 Gbit/s RZ signal transmission.

Hierarchical hybrid OTDM/WDM network

Hierarchical hybrid OTDM/WDM network is proposed for the future core-network. As its enabling technologies, C- and L-wavelength-band generation, OTDM-WDM mutual multiplexing format conversions, and ultrafast OTDM wavelength-band conversions are reported.