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. 19, 2008
Filed:
Feb. 28, 2005
Hiroyuki Yoshikawa, Machida, JP;
Shunsuke Hirano, Yokohama, JP;
Tatsuto Oka, Yokohama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A two-point frequency modulation apparatus is provided that reduces input timing difference and improves modulation accuracy. Two-point frequency modulation apparatushas: PLL circuit; frequency division ratio generatorthat generates the frequency division ratio in frequency dividerbased on first digital baseband signal Sand carrier signal; adderthat adds second digital baseband signal Sto the output signal of loop filter; a delay index calculator (filter coefficient calculator) that calculates the delay index based on the magnitude of change in the amplitude of the output signal of adder; and a delay adjuster (digital filter) that shifts the phase of one of first digital baseband signal Sand second digital baseband signal Saccording to the delay index so as to reduce the phase difference.