Franz Dr. Auracher

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. >

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.