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. 20, 2004
Filed:
Jan. 29, 1999
David L. Hershberger, Nevada City, CA (US);
Abstract
A digital television transmitter for an ATSC or NTSC signal includes a digital vestigial sideband modulator having a digital sinusoidal source. A digital multiplier arrangement multiplies a digital signal including the information in the digital television signal by a sequence derived by the digital sinusoidal source to derive plural orthogonally phased digital product signals. A digital lowpass filter arrangement passes low frequency components of the plural digital product signals and rejects high frequency components of the plural digital product signals. A signal combiner arrangement combines a carrier with signals containing information passed by the lowpass filter arrangement necessary to derive a vestigial sideband signal. The combiner arrangement includes at least one digital to analog converter that in different embodiments derives a vestigial sideband signal that modulates an I.F. or R.F. carrier.