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:
Apr. 11, 2000
Filed:
Mar. 04, 1999
Thomas M Walley, Loveland, CO (US);
Jacob L Bell, Ft. Collins, CO (US);
William L Pherigo, Jr, Ft. Collins, CO (US);
Hewlett Packard Company, Palo Alto, CA (US);
Abstract
Disclosed is a system and method for generating a data sequence from a two frequency coherent phase signal. The system comprises an integrated magnetic read channel that includes a magnetic reader circuit configured to generate an analog two frequency coherent phase (F2F) signal from a magnetic strip, the analog F2F signal having a number of alternating positive and negative peaks having a respective positive and negative transitions therebetween. The output of the magnetic reader circuit is applied to an analog-to-digital converter configured to convert the analog F2F signal into a digital F2F signal. Thereafter, the digital F2F signal is applied to a peak detector configured to identify the alternating negative and positive peaks. The magnetic read channel also includes a transition calculator configured to determine a transition time between each of the consecutively positioned alternating positive and negative peaks, and a frequency locked loop configured to determine a transition type for each of the transition times. Finally, the output of the frequency locked loop is applied to a data separator configured to determine a data value from the transition types.