Rockwell International Corporation

Thomas R Hope

Roger K Loper

Robert A Newgard

Charles S Farlow

Richard A Groshong

A system connecting and controlling gain and phase errors in a direct conversion receiver having a pair of signal channels carrying I and Q baseband signal components in a quadrature relationship. The system operates by treating all phase and gain errors as resident in the Q channel and thus describes an iterative process generating a plurality of intermediary signals that in turn incorporate a trigonometric product of the IF signal and the I and Q signal component to produce a pair of correction factors that ideally maintains a matched quadrature relationship between the two signal channels.

System for correcting quadrature gain and phase errors in a direct

A communication system and a method for using an approximating frequency synthesizer with frequency correction by digital signal processing (DSP) means to provide a radio transmitter or receiver with rapid high resolution tuning capabilities. A user selects a frequency upon which he wishes to transmit or receive information. An approximating synthesizer is used to provide an RF injection frequency. A radio controller interprets the user selected frequency and determines the closet available approximating synthesizer frequency. The controller commands the approximating synthesizer to the determined available frequency and calculates the difference in the determined available frequency and the user selected frequency. The calculated difference or error is passed on to the DSP for correction during frequency mixing in a single or multiple step process.

Growing community of inventors

Mount Vernon, IA, United States of America

Thomas R Hope