Dynamic Optical Path Switching in 172-Gb/s OTDM Transmissions of Ultra-High Definition Video Signals Using Fast Channel-Identifiable Clock Recovery and Integratable Devices

We demonstrate dynamic optical path switching in 172-Gb/s OTDM transmissions of real ultra-high definition (UHD) video signals. To allow integration, the 172-Gb/s OTDM transmission system was composed of semiconductor devices, which are newly developed CMOS-based transceivers, quantum-dot SOAs and monolithic all-optical gates based on inter-sub-band transitions in a quantum well waveguide. In order to realize dynamically switchable OTDM (DS-OTDM), we developed a novel clock distribution scheme using an optical null header (ONH). The ONH, which was inserted between the OTDM signal pulses with a repetition rate equal to the clock frequency, enabled to achieve channel identification and fast yet robust clock recovery. An uncompressed UHD video signal, which required a bandwidth of 72 Gb/s for the real-time transmission, was transmitted using two channels of the 172-Gb/s DS-OTDM signal. The two channels were de-multiplexed at the same time immediately after the optical path switching. Through optical path switching, two UHD video signals were dynamically switched within a switching time of 15 μ m and displayed on a screen successively.