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. 03, 1989
Filed:
Jul. 21, 1988
Masaru Yamaguchi, Tokyo, JP;
Takenori Ogata, Miyagi, JP;
NEC Corporation, Tokyo, JP;
Abstract
A digital automatic line equalizer for compensating distortion of a digital signal transmitted through a transmission line comprises a transversal filter having a set of tap gains for producing an equalized signal as a filter output from the digital signal incoming thereto. A first multiplier squares a current one of the filter output to produce a squared signal and other multipliers multiply the current and the previous ones of the filter outputs to produce product signals. In a calculator, the product signals are weighted and are, thereafter, summed together with the squared signal to produce summed signals which are averaged for a predetermined time duration into a mean value. A controller has a plurality of sets of values for the set of tap gains, compares the mean value with a reference value to produce an error signal and determines one set of the plurality of sets of values in response to the error signal to make the set of tap gains equal to the set of values thereby to maintain the mean value to the reference value so that the transversal filter produces the equalized signal.