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:
Dec. 04, 2001
Filed:
Feb. 25, 2000
Thorsten Nygren, Täby, SE;
Alina Oramas Alvarez, Upplands Väsby, SE;
Telefonaktiebolaget LM Ericsson (publ), Stockholm, SE;
Abstract
A reflective predistorter compensates for phase and amplitude variations imposed on an input signal by one or more non linear transfer characteristics of, for example, a power amplifier operating at or near saturation. The predistorter includes a hybrid having an input terminal, an output terminal and at least two relative phase terminals separated by 90 degrees. A first compensation circuit may be coupled to one of the relative phase terminals and may include a combination of linear and passive non-linear circuit elements. A second compensation circuit, identical to the first compensation circuit may be coupled to an other of the relative phase terminals includes a second combination of linear and passive non-linear circuit elements. The passive non-linear circuit elements may be one or more diodes and if more than one, the diodes are not configured as antiparallel. A first and second bias control circuit may be included for controlling a bias level in the first and second compensation circuit.