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:
Jul. 24, 2012
Filed:
Oct. 07, 2009
Applicants:
Koichi Aratani, Yokohama, JP;
Hirotake Ishii, Yokohama, JP;
Dan Xu, Fujisawa, JP;
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H04L 27/06 (2006.01);
U.S. Cl.
CPC ...
Abstract
An OFDM demodulator which does not require a reference signal for synchronization of carriers and can reduce influence of phase rotation by a propagation path when carrier synchronization is made. The OFDM demodulator performs Fourier transform plural times in 2 or more different operation ranges for the same OFDM symbol, calculates phases of sub carriers from the plural-time results of the Fourier transform, compares the calculated phases for each of the plural-time results of the Fourier transform and detects an error in frequency of reproduction carrier from the compared results.