Patent ID: 9014574
Filing Date: 2015-04-21
Classification: H04B,H04J

Abstract:
1. An optical receiver, comprising: a coherent optical detector receiving an optical signal in which a plurality of BPSK modulated carrier waves are polarization-multiplexed, performing coherent detection by mixing the received optical signal with local light, and outputting a plurality of first electrical signals corresponding to the plurality of carrier waves; a butterfly FIR filter receiving the plurality of first electrical signals and extracting a plurality of second electrical signals corresponding to each of the plurality of carrier waves from the plurality of first electrical signals; and a coefficient controller calculating a sum of respective phases of the second electrical signals output from the butterfly FIR filter, adaptively controlling tap coefficients of the butterfly FIR filter so that the calculated phase sum may become equal to 0 or π, and outputting tap coefficients after being controlled to the butterfly FIR filter.