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. 29, 2007
Filed:
Jun. 19, 2003
Mitsuya Komamura, Saitamaken, JP;
Mitsuya Komamura, Saitamaken, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
A pulse width modulator for producing a PWM signal having reduced nonlinear distortion through interpolation processing with fewer computation steps is provided. The computational processing, W={1+α(X−X)}{0.25 (X+X)}+0.5, is performed in accordance with successive sample values (X, X) in a PCM data train to determine a weighting factor (W). The computational processing, Xq=0.5·X(W−W)+X(1−W)+0.5·X(W+W), is performed using the sample values (X, X), a sample value (X) previous to the sample value (X), and the weighting factor (W) to thereby determine an interpolated sample value (Xq) having an amplitude close to that of an original analog signal (X(t)) generating the PCM data train. A point in time (tq) at which a reference signal (R(t)) takes on the interpolated sample value (Xq) is then determined to produce a PWM signal (Spwm) which is logically inverted at the point in time (tq).