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. 04, 2000
Filed:
Feb. 13, 1998
Terence L Johnson, Austin, TX (US);
Albert H Higashi, Gilbert, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An equalizer (106, 146) for use in systems such as an asymmetric digital subscriber line (ADSL) transceiver (5) reduces the number of calculations required for updating the equalizer coefficients. The equalizer (106, 146) takes advantage of the substantially symmetrical phase and amplitude distortion of the signal constellation, which causes both the amplitude and the phase relationship of the calculated error term for each constellation point to be equal. Instead of performing a full complex multiplication, the equalizer (106, 146) uses some but not all of the product terms between the real and imaginary components of the calculated error term and the conjugate of the received data estimate in the coefficient update calculation. The result is then scaled to account for the missing terms. The resulting equalizer (106, 146) requires fewer calculations for coefficient updating.