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:
Feb. 16, 1999
Filed:
Sep. 05, 1996
Naoyuki Saito, Kawasaki, JP;
Takanori Iwamatsu, Kawasaki, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A carrier reproducing circuit for detecting a phase error when an inputted baseband signal is out of phase and bringing the baseband signal into phase even in QAM systems in which normal signal points are located in a non-square pattern in a phase-amplitude signal space. When the baseband signal is out of phase, a first region decision circuit detects a presence of the baseband signal in a first region and outputs a first signal, and a second region decision circuit detects a presence of the baseband signal in a second region and outputs a second signal. If the second signal is not outputted over a predetermined period of time around the time at which the first signal is outputted, then a selective outputting circuit outputs a phase error detected by a phase error decision circuit with respect to the baseband signal at the time the first signal is outputted, to a control signal generator. If the second signal is outputted in the predetermined period of time, then the selective outputting circuit outputs the phase error detected by the phase error decision circuit with respect to the baseband signal at the time the first signal is outputted in a preceding cycle to the control signal generator.