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. 11, 1990
Filed:
Oct. 17, 1988
Applicant:
Inventors:
Don R Holcomb, Sr, Scottsdale, AZ (US);
Mark J Brown, Phoenix, AZ (US);
Lawrence R Schumacher, Mesa, AZ (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
455182 ; 455192 ; 455260 ; 455296 ; 331 / ;
Abstract
An additional mixer is included in the feedback loop of a PLL which can be one of the local oscillators of a dual conversion system. A fine tuning frequency synthesizer is coupled to an input of the additional mixer for providing fine frequency control of the PLL. The fine tuning frequency synthesizer can include an additional phase locked loop. Also, a feedback signal for suppressing noise created by another local oscillator can also be applied to the additional mixer.