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:
Jun. 01, 2004
Filed:
May. 23, 2000
Kazuhiko Uchiyama, Saitama, JP;
Sei Kato, Saitama, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
An intermediate frequency signal S is demodulated and the noise component contained in a null portion (no-signal portion) is detected as the noise component contained in a signal of the sub-carrier frequencies. The frequency f of a reference frequency signal LO of a local oscillator is feedback-controlled in accordance with the noise component thus detected. Further, the frequency f of the reference frequency signal LO is feedback-controlled in accordance with an error rate detected by an error correction section . Thus, the sub-carriers within the intermediate frequency signal S subjected to the frequency conversion by a mixer based on the reference frequency signal LO thus feedback-controlled is separated from the noise component on the frequency axis. The intermediate frequency signal S is subjected to the Fourier transformation by a digital mixer/FFT calculation section , so that the noise component can be suppressed.