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. 02, 2010
Filed:
Jun. 19, 2007
Hiroki Kimura, Hokkaido, JP;
Tsukasa Kobata, Hokkaido, JP;
Yasuo Kitayama, Hokkaido, JP;
Naoki Onishi, Hokkaido, JP;
Hiroki Kimura, Hokkaido, JP;
Tsukasa Kobata, Hokkaido, JP;
Yasuo Kitayama, Hokkaido, JP;
Naoki Onishi, Hokkaido, JP;
Nihon Dempa Kogyo., Ltd., Tokyo, JP;
Abstract
A digitally controlled PLL oscillation circuit has a VCO, a frequency divider, a reference oscillation circuit, an A/D converter, a phase comparator, a digital filter, a D/A converter, and an analog filter. A reference signal supplied from the reference oscillation circuit is output through a narrow-band crystal filter (MCF) to the A/D converter to cancel noise, jitter and a spurious wave included in the reference signal, making it possible to prevent the phase noise characteristic and spurious characteristic of a VCO output from being degraded.