Patent ID: 8340533
Filing Date: 2012-12-25
Classification: H04B

Abstract:
1. An optical balanced receiver comprising: an optical coupler for combining input optical information signal and optical reference signal and outputting two optical interfering signals whose phases are opposite to each other; two photodetectors for receiving the two optical interfering signals and outputting, as detection signals, electrical signals having amplitudes corresponding to the interference intensities of the received optical interfering signals; a balance compensation type difference device for compensating an intensity fluctuation component added to a difference signal of the two detection signals due to the difference in amplitude and/or delay between the detection signals output from the two photodetectors in accordance with an input control signal, and outputting the compensated difference signal of the two detection signals; and a control circuit for outputting the control signal to the balance compensation type difference device, wherein the balance compensation type difference device comprises: an analog-to-digital converter for converting the difference signal to a digital signal; and a digital signal processor for compensating the amplitude and/or delay of converted signal in accordance with the control signal from the control circuit.