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:
May. 21, 2013
Filed:
May. 22, 2009
Steven a Gronemeyer, Cedar Rapids, IA (US);
Steven A Gronemeyer, Cedar Rapids, IA (US);
CSR Technology, Inc., Sunnyvale, CA (US);
Abstract
Systems and methods for calibrating real time clock are provided. A representative receiver includes a GPS device comprising a real time clock (RTC) circuitry that generates RTC clock signals and a temperature compensated crystal oscillator (TCXO) that generates TCXO clock signals. A ratio counter circuitry receives both the RTC clock signals and the TCXO clock signals and determines a frequency ratio by comparing the RTC clock signals and the TCXO clock signals. A computing device receives the frequency ratio and estimates a current RTC frequency based on the received frequency ratio. The computing device is configured to calibrate an estimated RTC time being maintained at the RTC circuitry based on an estimated RTC frequency from a prior estimation, the current RTC frequency and an elapsed time of the RTC circuitry.