Patent ID: 6693970
Filing Date: 2004-02-17
Classification: H04L

Abstract:
A vector modulator circuit for performing a circular rotation of a vector in accordance with a predetermined modulation scheme, the vector comprising of orthogonal I and Q components of a radio frequency signal to be transmitted, and formed from an IIN and QIN data streams applied to the vector modulator circuit,wherein the vector modulator circuit comprises: a plurality of digital rotation stages coupled in sequence, wherein the first stage receives the IIN and QIN data streams and the last stage outputs a vector comprising of the orthogonal I and Q components of a digital intermediate frequency signal; a plurality of pipeline registers and adding/subtracting elements for forming each of the digital rotation stages, each stage rotating an input vector by an individual elementary angle, said input vector being the output vector of the previous digital rotation stage; an angle computation block for counting a plurality of individual elementary rotation angles, each of the angles being applied to one of the rotation stages; and a phase accumulator for receiving a frequency control word and for generating at an intermediate frequency input word ZIN for applying to the angle computation block.