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:
Jul. 31, 2007
Filed:
Dec. 16, 2002
Peter Zahariev Rashev, Calgary, CA;
David M. Tholl, Calgary, CA;
Christopher John Leskiw, Calgary, CA;
Peter Zahariev Rashev, Calgary, CA;
David M. Tholl, Calgary, CA;
Christopher John Leskiw, Calgary, CA;
Nortel Networks Limited, St. Laurent, CA;
Abstract
A bank of complex gain elements is used to provide a step-wise approximation of an arbitrary complex-gain predistortion function for a nonlinear transmitter. The bank of gain elements is in an adaptive loop realizing adaptive control. The adaptive loop is closed between an Input of the gain bank and an output of the transmitter through a linear receiver at an adaptive controller composed of a bank of proportional-integral (PI) controllers. The real and imaginary parts of each predistortion gain element are controlled by a corresponding adaptive PI controller. The signals processed by the adaptive controller are represented in orthogonal coordinates in terms of real and imaginary number pairs of complex numbers. The adaptive controller achieves unconditionally stable operation independently from the arbitrary phase rotation in the input signal or the adaptive loop.