Abstract
We report the development of two lab prototypes for all optical clock recovery and optical synchronization, composed by a DFB semiconductor laser driven by a ultra-fast switching current circuit. It was verified that a fast switch of the laser bias current accomplished by the strong feedback in the external cavity induce the self-pulsation needed for correct operation. In the presence of optical RZ signals, the device leaves is natural pulsation frequency synchronizing with the input data.

Abstract
CANopen is a truly open protocol that has not been developed by one company alone. Several working groups, consisting of many different device manufacturers and end-users, have co-operated to produce the CANopen standards, now under the supervision of the CAN in Automation organisation. CANopen has been produced as a result of EU funding. This article gives an overview of some of the fundamental concepts of CANopen communication and of CANopen implementation. © IEE: 1999.

Abstract

Abstract
This paper summarizes the research activities of the optical communications group at University of Aveiro and Institute of Telecommunications - Aveiro pole. Several activities like clock recovery systems, both electrical and all optical, electrical equalizers for very high bit rate DST systems, post-detection filters for multigigabit optical receivers, soliton systems, simulation work on WDM, DST, EDFA and short pulse generation for high bit rate systems are presented.

Abstract

Abstract