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:
Nov. 25, 2025
Filed:
Sep. 29, 2023
Nec Corporation, Tokyo, JP;
Masaki Sato, Tokyo, JP;
NEC CORPORATION, Tokyo, JP;
Abstract
A distortion compensation filter whose filter coefficient is adaptively controlled compensates for a distortion included in a reception signal obtained by performing coherent reception of a signal transmitted from a transmitter in a receiver. A group delay ripple calculation device calculates a group delay included in the reception signal based on a filter coefficient of a distortion compensation filter and calculates group delay ripple from the calculated group delay. The feedback calculation unit calculates a phase response based on the calculated group delay ripple. The feedback calculation unit feeds the calculated phase response back to one or more filters having a phase compensation function disposed in a stage before an adaptive equalization filter included in the receiver, and causes one or more filters to at least partially compensate for the group delay ripple.