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:
Apr. 15, 2003
Filed:
Feb. 19, 1999
Tatsuya Tsuruoka, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A DAB (Digital Audio Broadcasting) receiver includes a delay circuit for delaying a received DAB signal by a prescribed period, a correlation circuit for taking correlation between a delayed output of the delay circuit and the DAB signal, a moving average circuit for moving-averaging a correlation output of the correlation circuit over a width that is equal to a guard period, a peak detection circuit for detecting a position in time of a peak of a moving average output of the moving average circuit, a calculation circuit for calculating an error in a reception frequency based on a phase deviation in the DAB signal at the position in time that is indicated by a peak detection output of the peak detection circuit, an FFT (Fast Fourier Transform) circuit for subjecting the DAB signal to FFT processing, and a detection circuit for determining a reception center frequency based on an FFT output of the FFT circuit. The error in the reception frequency is corrected by controlling a local oscillation frequency based on a calculation output of the calculation circuit. An error in the reception frequency is corrected by performing carrier shifting based on a detection output of the detection circuit. As a result, the time necessary for tuning can be shortened.