| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical communication device capable of performing proper adjustment of an operating point of a light modulation means. <P>SOLUTION: An addition means 1d sums up a bias voltage of a bias voltage generating means 1b and a pilot signal of a pilot signal generating means 1c. The light modulation means 1e modulates the light of the light source 1a based on an electric signal and also modulates the light by the signal based on the addition means 1d, to output an optical signal. A monitoring means 1f outputs a monitor signal monitoring the level of the optical signal. A reference signal output means 1g outputs a reference signal having the same phase as that of a pilot signal included in the monitor signal. A pilot-signal synchronous detection means 1h performs synchronous detection of the monitor signal with the reference signal. A noise synchronous detection means 1i extracts noise contained in the monitor signal and performs synchronous detection of the noise with the reference signal. A control signal output means 1j subtracts a synchronous detection value of the noise synchronous detection means 1i from a synchronous detection value of the pilot signal synchronous detection means 1h, to output a control signal. <P>COPYRIGHT: (C)2008,JPO&INPIT |
