All-Optical Switches in Optical Time-Division Multiplexing Technology: Theory, Experience and Application

Optical time division multiplexing (OTDM) is one of the promisinig ways for the future high speed optical fiber communication networks. All optical switch is, being one of the core technologies of OTDM systems and networks, crucial to realize the various signal processes including time division demultiplexing, packet switching, all optical regenerating and so on. This thesis mainly studies various all optical switch technologies and their utilization in the fields of all optical signal processings in the OTDM systems and networks. The main jobs are listed as follows.\; (1) A novel all optical ultrafast demultiplexing scheme using the soliton self trapping effect in birefringent fiber is proposed.\; (2) The demultiplexing performance of the Nonlinear Optical Loop Mirror(NOLM) is thoroughly analyzed and its optimization is further discussed.\; (3) The performance analysis and the configuration optimization of the all optical switches based on the Semiconductor Optical Amplifier(SOA) are systematically presented. The speed limitation of the all optical SOA switches induced by the fast gain depletion of SOA is discussed. Besides, a novel SOA switch is proposed, which adopts the asymmetric Mach Zehnder Interferometer configuration.\; (4) The 8×2\^5 Gb/s OTDM experimental transmission system along 105 km standard fiber is realized using the NOLM demultiplexer.\; (5) The NOLM switch is used to realize the all optical 3R regeneration of 2\^5 Gb/s Return to Zero signal.\; (6) The feasibility and limitation of the all optical SOA packet switch is discussed. And a developed MZI configuration of SOA packet switch is further shown to improve the packet switching performance. Finally, an all optical packet dropping node suitable in the networks with ring or bus configuration and an all optical packet switching node in the ShuffleNet networks are proposed to show the feasibility of all optical packet switching through combining the all optical switches and the reasonable logic decisions.