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:
Dec. 16, 2003
Filed:
Feb. 27, 2002
Applicant:
Inventor:
Takahiko Kishi, Yokohama, JP;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03B 2/100 ;
U.S. Cl.
CPC ...
H03B 2/100 ;
Abstract
A frequency synthesizer that improves a unique DDS characteristic, while maintaining a circuit scale (ROM size) of a direct digital synthesizer (DDS). A first digital signal generator generates a quantized frequency signal, and a second digital signal generator generates a frequency signal having a fine frequency resolution and many spurious signals as compared with the first digital signal generator. A filter performs band rejection on an output of the second digital signal generator, and a mixer mixes an output of the first digital signal generator with an output of the filter.