Digital signal processing in 112-Gb/s polarization-multiplexed 16-QAM coherent optical receiver

摘要

In this paper, we discuss digital signal processing methods and its impacts in 112-Gb/s polarization-division-multiplexed 16-ary quadrature amplitude modulation (PDM 16-QAM) coherent optical receiver. Impacts of in-phase/quadrature-mismatch (IQ-mismatch) in the receiver are investigated and the IQ-mismatch compensation by digital signal processing is examined. We also analyze a 16-QAM optical signal generated by applying four-level electrical signals to single in-phase/ quadrature (IQ)-modulator.