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. 08, 1998
Filed:
Jun. 01, 1995
Gregg Edward Rasor, Boynton Beach, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An automatic frequency control is implemented in a selective call receiver (100) having a controllable frequency synthesizer (203). The output frequency of the synthesizer an is derived from a frequency reference element (205). A temperature sensor (206) with substantial thermal coupling to the frequency reference element (205) produces a temperature signal representative of an operating temperature associated with the frequency reference element. The temperature signal is coupled to a controller (105) that operates to execute a microcode program implementing the automatic frequency control. Responsive to the temperature signal and at least one set of parameters representing a predetermined temperature versus frequency characteristic of the frequency reference element, a correction factor is generated and programmed in the frequency synthesizer (203). The correction factor corrects the output frequency to reflect a frequency error of substantially zero parts per million with respect to a desired operating frequency.