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:
Sep. 25, 2001
Filed:
Dec. 03, 1999
Youko Omori, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A signal estimator estimates a transmission signal series using Viterbi algorithm, and outputs an estimated signal and a minimum path metric signal. A switching unit is controlled by a control signal in such a manner that, for a certain period from the start of the operation of PLL which requires quick response, a minimum path metric history signal is selected, while, in the other case, an estimated signal is selected. A replica generator generates a replica signal using a signal output from the switching unit. The generation of the replica signal using the path metric history signal offers quick response, but on the other hand, the accuracy is low. On the other hand, the use of the estimated signal offers high accuracy, but on the other hand, the response speed is low. Thus, a phase change contained in a received signal is corrected in a highly accurate and quick manner.