| US 7,580,640 B2 | ||
| Method and apparatus for extracting optical clock signal | ||
| Jaemyoung Lee, Seoul (Korea, Republic of); and Je Soo Ko, Daejeon (Korea, Republic of) | ||
| Assigned to Electronics and Telecommunications Research Institute, Daejeon (Korea, Republic of) | ||
| Filed on Oct. 12, 2006, as Appl. No. 11/546,749. | ||
| Claims priority of application No. 10-2005-0096948 (KR), filed on Oct. 14, 2005. | ||
| Prior Publication US 2007/0086784 A1, Apr. 19, 2007 | ||
| Int. Cl. H04B 10/00 (2006.01); H04B 10/12 (2006.01) | ||
| U.S. Cl. 398—155 [398/160; 359/325; 359/341.2; 359/495; 359/515] | 18 Claims |
| 1. An apparatus for extracting an optical clock signal, the apparatus comprising:
a reflector rotating frequency components of an input optical signal by a predetermined angle and then reflecting them;
a bi-directional amplifier amplifying frequency components of the input optical signal before transmitting them to the reflector
and amplifying frequency components reflected from the reflector;
a polarization beam splitter splitting a predetermined polarization component from the optical input signal through an input
terminal;
a Fabry-Perot filter selecting frequency components for clock signal extraction from the predetermined polarization component
received from the polarization beam splitter, transmitting the selected frequency components to the bi-directional amplifier,
and removing noise from the frequency components that have been reflected from the reflector and amplified by the bi-directional
amplifier; and
a photodetector receiving the noise-removed frequency components from the Fabry-Perot filter and obtaining a beat frequency
component from the noise-removed frequency components to extract an optical clock signal.
|