IEEE

IEEE - Complex signal processing is not complexIEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS―I: REGULAR PAPERS, VOL. 51, NO. 9, SEPTEMBER 2004

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Complex Signal Processing is Not Complex
Kenneth W. Martin, Fellow, IEEE
Abstract―Wireless systems often make use of the quadrature relationship between pairs of signals to effectively cancel out-of-band and interfering in-band signal components. The understanding of these systems is often simplied by considering both the signals and system transfer functions as “complex” quantities. The complex approach is especially useful in highly integrated multistandard receivers where the use of narrow-band xed-coefcient lters at the RF and high IF must be minimized. This paper rst presents a tutorial review of complex signal processing for wireless applications. The review emphasizes a graphical and p