Patent ID: 6359523
Filing Date: 2002-03-19
Classification: H04L

Abstract:
An orthogonal modulator, wherein an offset between an in-phase component (I signal) and a quadrature component (Q signal) is eliminated, which comprises:a generation means for generating base band signals on the basis of said I signal, said Q signal, an inverted signal of said I signal (IB) and an inverted signal of said Q signal (QB); a mixing means for mixing said base band signals and a plurality of carrier waves; an extraction means for extracting DC levels of said I signal (I), said inverted signal of said I signal (IB), said Q signal (Q) and said inverted signal of said Q signal (QB) in the signal outputted from said mixing means; a comparison means for comparing said DC levels of said I, IB, Q and QB signals with each other; an addition means for adding a comparison result to another comparison result; and an offset elimination means for subtracting addition results from said I, IB, Q and QB signals before said I, IB, Q and QB signals are applied to said mixing means.