A. Ebberg

Comparison of polarization handling methods in coherent optical systems

The authors compare three polarization handling methods in coherent optical systems. These methods are: endless polarization control, polarization diversity, and data-induced polarization switching. These methods are also compared with active, data-synchronous polarization switching. It is seen that endless polarization control is potentially the most powerful candidate, however, the choice of polarization control devices remain questionable. Polarization diversity is as versatile as polarization control and is potentially the fastest method; however, it yields lower receiver sensitivity. Endless control or a well-designed diversity receiver should be used for coherent trunk systems. Data-induced polarization switching is restricted to frequency-shift-keying (FSK) systems. It promises a loss span similar to that of diversity, but is far simpler, which makes it recommendable for FSK distribution systems. >

A coherent OFDM switching system for flexible optical network configuration

A coherent optical switching node based on the combination of a frequency conversion stage with a space switching matrix is proposed for flexible interconnection of future integrated broadband communication networks. The basic system concept is presented together with the architecture of a demonstrator, which allows one to study the functionality available in future networks. The major subsystems and components of the demonstrator are described, and experimental results concerning frequency stabilization, frequency switching, and space switching are presented. >

Von GSM zu DECT: Die mobile Sprach- und Datenkommunikation

Dr.-Ing. Hermann Rodler studierte Nachrichtenund Hochfrequenztechnik an der T U München und promovier te 1993 an der Ruhr-Universität Bochum. Seit 1985 ist er bei der Siemens AG tätig, bis 1992 im Bereich Forschung und Entwicklung von optischen Kommunikat ionssys temen. Bis 1996 war er Leiter des Technology Department von Siemens in Japan, danach Projektleiter für die Entwicklung von IP Telefonie und Mobilkommunikat ions-Prototypen. Seit 1997 ist er für die strategische Produktplanung von Sprachund Daten-Kommunikat ionssystemen im Geschäftsbereich Information and Communication Networks verantwortlich.

Comparison of endless polarization control and data- induced polarization switching in an ultrasensitive FSK hetero- dyne system

Endless polarization control1,2 (EPC) and data-induced polarization switching3,4 (DIPS) have been suggested to solve the polarization problem in optical FSK heterodyne receivers. We compare both methods, we believe for the first time, in terms of receiver sensitivity and polarization response speed.

Pattern-independent FSK heterodyne transmission with endless polarization control and a 119 photoelectrons/bit receiver sensitivity

Abstract We demonstrate 140-Mbit/s FSK transmission with a -56.7-dBm receiver sensitivity. The system features endless polarization control, Manchester coding to overcome the nonuniform FM response of the DFB laser, and a highly efficient sub-carrier demodulation scheme.