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:
Oct. 13, 2015
Filed:
Jul. 25, 2014
Research & Business Foundation Sungkyunkwan University, Suwon-si, KR;
Research & Business Foundation SUNGKYUNKWAN UNIVERSITY, Suwon-si, KR;
Abstract
An apparatus and method for compensating output signals of a magnetic encoder are disclosed. The apparatus includes a pre-calibration unit, an advanced phase detector, a loop filter, a voltage controlled oscillator (VCO), and a pulse generator. The pre-calibration unit obtains two phase-compensated waveforms through trigonometric function operations, and adjusts the amplitudes of the two phase-compensated waveforms to the same value, thereby generating input sine and cosine waves. The advanced phase detector generates an error output signal through trigonometric function operations. The loop filter sets the filter transfer function of an active lead-lag filter, and then filters the error output signal. The VCO generates a compensated signal. The pulse generator outputs a phase index, and generates two output pulses having a phase difference of 90 degrees in accordance with a pulse generation rule of a look-up table.