Accession Number : ADD011679
Title : Orthogonalizer for Inphase and Quadrature Digital Data.
Descriptive Note : Patent,
Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC
Personal Author(s) : Lewis,B L
Report Date : 18 Dec 1984
Pagination or Media Count : 5
Abstract : This invention relates generally to radar systems and more particularly to methods and apparatus for correcting phase imbalances between inphase and quadrature channels of digital signal processing systems. Inphase and quadrature phase non-orthogonality (where by the term 'non-orthogonality' is meant correlation) has been a problem in digital signal processors such as adaptive moving target indicators (MTI) and coherent sidelobe cancellers. Adaptive interference cancelers are limited in the amount of interference they can cancel by the non-orthogonality of the inphase and quadrature data. An orthogonalizer is disclosed wherein a series of complex digital numbers is received, each number having correlated (non-orthogonal) real and imaginary parts; a weight is established which is a measure of the correlation; the product is formed of one of the parts of one of the received complex numbers with the weight; and the product is subtracted from the other part of the one received complex number to decorrelate (orthogonalize) the real and imaginery parts thereof.
Descriptors : *PATENTS, *DIGITAL DIFFERENTIAL ANALYZERS, DIGITAL SYSTEMS, COMPLEX NUMBERS, REAL NUMBERS, CORRELATION TECHNIQUES
Subject Categories : Statistics and Probability
Distribution Statement : APPROVED FOR PUBLIC RELEASE