Patent ID: 9215011
Filing Date: 2015-12-15
Classification: H04B

Abstract:
1. An optical receiver, comprising: a signal processor configured to perform digital signal processing on a polarization demultiplexed signal which is obtained by demultiplexing a polarization multiplexed signal corresponding to a reception signal, the signal processor includes: an adaptive equalization circuit configured to compensate for the polarization demultiplexed signal by control of a filter coefficient; a first frequency offset estimation circuit configured to receive a first polarization demultiplexed signal which is diverged at a preceding stage to the adaptive equalization circuit and estimate a first frequency offset of the first polarization demultiplexed signal for each of polarized waves; a second frequency offset estimation circuit to receive a second polarization demultiplexed signal diverged at a succeeding stage to the adaptive equalization circuit and estimate a second frequency offset of the second polarization demultiplexed signal for each of the polarized waves; and a decision circuit to decide whether the filter coefficient is correct based on a first difference between the first frequency offset and the second frequency offset and output, when the decision circuit decides that the filter coefficient is incorrect, a first trigger for re-calculation of the filter coefficient to the adaptive equalization circuit.