Shunsuke Mitani

NRZ-OOK-to-RZ-BPSK modulation-format conversion using SOA-MZI wavelength converter

A novel all-optical modulation-format conversion from nonreturn-to-zero on-off keying (NRZ-OOK) to return-to-zero binary phase-shift keying (RZ-BPSK) is proposed. A Mach-Zehnder interferometric (MZI) wavelength converter consisting of integrated semiconductor optical amplifiers (SOAs) is utilized to implement the proposed format conversion. Error-free operation at a bit rate of 10.7 Gb/s is experimentally demonstrated in order to show the feasibility of the proposed scheme. The received sensitivity of the converted signal is improved by 2.9 dB compared with a back-to-back NRZ-OOK signal at BER=10 -9. In addition, a reasonable dispersion tolerance of the converted signal up to plusmn500 ps/nm is observed. The numerical simulation based upon the carrier-rate equation verifies the experimental results

All-optical modulation format conversion from NRZ-OOK to RZ-QPSK using parallel SOA-MZI OOK/BPSK converters

A novel all-optical modulation format conversion from non-return-to-zero on-off-keying (NRZ-OOK) to return-to-zero quadrature-phase-shift-keying (RZ-QPSK) is proposed and experimentally demonstrated. The proposed format conversion scheme is based on parallel Mach-Zehnder interferometric (MZI) OOK/binary-PSK (BPSK) converters, consisting of integrated semiconductor optical amplifiers (SOAs). We experimentally demonstrate that in both decoded channels of the converted RZ-QPSK signal bit error rate (BER) curves show almost the same receiver sensitivity at a symbol-rate of 10.7 Gsymbol/s. In addition, a reasonable dispersion tolerance of the converted signal up to +295 ps/nm is observed. The numerical simulation based upon carrier rate equation verifies the experimental results.

All-optical format conversion from NRZ-OOK to RZ-BPSK using SOA-MZI wavelength converter

We propose a novel all-optical NRZ-OOK/RZ-BPSK format conversion scheme, using cross-phase modulation effects in a MZI-SOA. We experimentally demonstrate error free conversion at 10.7 Gb/s with a negative power penalty of 2.9 dB

Adaptive Optical PMD Compensation with Twin Chirped Fibre Gratings for a 40Gbps CSRZ-DQPSK signal

Twin chirped fibre gratings and a DOP monitoring scheme realize adaptive PMD compensation for CSRZ-DQPSK signals. The proposed scheme successfully suppressed degradation of the signal quality after 320km transmission over a high PMD span.

Wavelength Conversion Characteristics of SOA-MZI Based All-Optical NRZ-OOK/RZ-BPSK Modulation Format Converter

All-optical wavelength conversion and modulation format conversion will be needed in the next generation high-speed optical communication networks. We have proposed and successfully demonstrated the error free operation of all-optical modulation format conversion from NRZ-OOK to RZ-BPSK using SOA based MZI wavelength converter. In this paper, we experimentally investigate the wavelength conversion characteristics of the proposed NRZ-OOK/RZ-BPSK modulation format converter. The results show that error free modulation format conversion is possible over the entire C band.

All-optical NRZ-OOK to RZ-QPSK conversion using parallel SOA-MZI OOK/BPSK converters

We propose a novel all-optical NRZ-OOK/RZ-QPSK modulation format converter using parallelized SOA-MZIs and demonstrate the proof-of-the-principle experiment at 10.7 GSymbol/s by using the test parallel SOA-MZI OOK/BPSK converters.