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:
Jun. 27, 2023
Filed:
Feb. 28, 2022
Kddi Corporation, Tokyo, JP;
Nec Platforms, Ltd., Kawasaki, JP;
Shohei Beppu, Fujimino, JP;
Takehiro Tsuritani, Fujimino, JP;
Koji Igarashi, Fujimino, JP;
Masahiro Shigihara, Kawasaki, JP;
Masahiro Kikuta, Kawasaki, JP;
KDDI CORPORATION, Tokyo, JP;
NEC Platforms, Ltd., Kawasaki, JP;
Abstract
A reception apparatus includes: a receiving unit configured to coherently detect an optical signal and output an electrical signal containing a modulated signal and a pilot signal; a first compensating unit configured to detect a frequency of the pilot signal by performing a DFT of the electrical signal, and determine and compensate for frequency error in the electrical signal based on a reference frequency; a frequency converting unit configured to convert the frequency of the pilot signal after the compensating such that the frequency of the pilot signal is lowered by the reference frequency; and a second compensating unit configured to determine frequency error in the modulated signal after the compensating by performing a DFT on the pilot signal after the frequency converting and detecting a frequency of the pilot signal after the frequency converting.