Abstract

ARVIZU-MONDRAGON, A.; MENDIETA-JIMENEZ, F.J.  and  SANCHEZ-LOPEZ, J. de D.. Optical Phase Estimators in Modern Homodyne Communications Systems. Ing. invest. y tecnol. [online]. 2009, vol.10, n.3, pp. 187-195. ISSN 1405-7743.

This work consists of the synthesis of an optimal estimator for a random phase modulation onto a carrier to be received by a coherent detector. Our application is oriented to homodyne detection with PSK format, in modern optical communication systems. We mecha nize an estimator operating with a baseband observable in additive noise employing a state variable model for the communication channel and optimal estimation techniques. To as sess the performance of the general structure and simplified versions of the estimator we made com puter simulations and calculated the r.m.s. value of the phase error. With these results we get practical estimators that we implemented using analog electronic circuitry and a DSP. The "constant variance" estimator exhibited the minimum r.m.s. value of its phase error obtained experimentally.

Keywords : Optimal estimation; homodyne detection; Wiener processes; phase modulation; state variable.