Investigation of Improvement of Dynamic Switching Operation for Wavelength Switch With Super-Structure-Grating (SSG)-DBR-LD, Delayed-Interference Signal-Wavelength Converter (DISC), and Bandpass Filter

We demonstrate dynamic wavelength switching operation using a super-structure grating (SSG)-DBR-LD and a semiconductor optical amplifier (SOA)-delayed-interference signal-wavelength converter (DISC) for optical packet switch and buffering systems. The wavelength conversion-type optical switch has the advantage of lowering packet blocking probability and reducing numbers of the required SOAs in the DISC-type wavelength converter. However, we confirmed that large optical spikes occur at the timing of wavelength switching due to the optical chirping. By detuning the center wavelength of a bandpass filter to suppress optical chirped wavelength component, we could reduce the intensity of the spikes. We also observed the alternate wavelength switching operation with small optical spikes with fixed detuning of the bandpass filter and the fixed optical phase bias of the Mach-Zehnder Delayed Interferometer (MZDI) by setting the small current variation of the SSG-DBR-LD for wavelength switching. Error free performance was also achieved under back-to-back and 50 km single mode fiber transmission.