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:
Aug. 08, 2000
Filed:
Sep. 11, 1998
Ronald D Boesch, Morrisville, NC (US);
Domenico Arpaia, Cary, NC (US);
Ericsson Inc., Research Triangle Park, NC (US);
Abstract
Modulation systems and methods compensate for the DC offset that is introduced by the digital-to-analog converter and/or the low pass filter thereof. Compensation is preferably provided in the digital domain, to thereby reduce DC offset within acceptable limits for the modulation that is being used. More preferably, compensation is provided by subtracting from the digital input signal, a digital value representing the DC offset in the filtered analog signal that is introduced by the digital-to-analog converter and/or the low pass filter. A sensor senses the DC offset in the filtered analog signal. An analog-to-digital converter is responsive to the sensor to convert the sensed DC offset into a digital offset signal. A subtractor is responsive to the analog-to-digital converter to subtract the digital DC offset signal from the digital input signal and to apply the digital input signal minus the DC offset signal, to the digital-to-analog converter.