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Spectral Analysis of OFDM Signals and Its Improvement by Polynomial Cancellation Coding

Overview In orthogonal frequency division multiplexing (OFDM) systems, the subcarriers are generated by an inverse discrete Fourier transform. In the literature, the spectra of these subcarriers are often represented by a sequence of sinc functions of the same polarity. This is not consistent with the intercarrier interference (ICI) cancellation properties of polynomial cancellation coding (PCC) or similar self-ICI cancellation schemes in OFDM. This paper shows the spectra of these subcarriers are more accurately represented by a sequence of sinc functions with alternating polarity. It is shown that the spectral rolloff of OFDM signals can be improved by PCC and the resultant OOB power is much reduced.

Further White Paper Details
Publisher	Institute of Electrical and Electronics Engineers	File Format	PDF, requires Acrobat Rdr 5
Date Published	January 2004	Downloads	13
Format	White Papers
Topics	Modems

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