The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 22, 2013
Filed:
Oct. 27, 2010
Hwan-seok Chung, Daejeon-si, KR;
Sun-hyok Chang, Daejeon-si, KR;
Jyung-chan Lee, Daejeon-si, KR;
Kwang-joon Kim, Daejeon-si, KR;
Hwan-Seok Chung, Daejeon-si, KR;
Sun-Hyok Chang, Daejeon-si, KR;
Jyung-Chan Lee, Daejeon-si, KR;
Kwang-Joon Kim, Daejeon-si, KR;
Electronics and Telecommunications Research Institute, Daejeon-Si, KR;
Abstract
An apparatus for receiving optical signals in DQPSK and method of controlling a phase offset in receiving optical signals for DQPSK is provided. An original optical signal modulated in DQPSK is received. The original optical signal is delayed by one bit to make a delay optical signal such that an interference on the original optical signal and the delay optical signal is performed. A control signal is generated by use of an interference result between the original optical signal and the delay optical signal. A phase offset for the interference between the original optical signal and the delay optical signal is controlled by use of the generated control signal. In receiving optical signals, the phase offset between the delay optical signal and the original optical signal is precisely controlled, thereby optimizing the transfer characteristics of an optical delay interferometer.