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:
Mar. 07, 1989
Filed:
Dec. 22, 1987
Ben Flugstad, Newman Lake, WA (US);
Raymond L Fried, Liberty Lake, WA (US);
Alan Hedge, Chapel Hill, NC (US);
Barton L McJunkin, Spokane, WA (US);
Mark D Talbot, Liberty Lake, WA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A phase-locked loop (PLL) frequency synthesizer having an analog, out-of-band component path and a digital, in-band component path to provide frequency modulation (FM) of the synthesized output signal is described. The in-band FM component is octave scaled by an analog scaling means and coupled to an analog-to-digital converter to provide a digital number to be decade added to the PLL divide number to change the PLL frequency in response to the in-band FM signal. The out-of-band FM component is also scaled and applied to a loop summing node and summed with the PLL error signal to vary the PLL frequency. The scaling in both the in-band component path and out-of-band component path is equalized to provide a flat frequency response. Additional, the in-band component is scaled to allow use of the analog-to-digital converter over its maximum range to maintain a high signal-to-noise ratio.