The Cyclic Prefix of OFDM/DMT – An Analysis
نویسندگان
چکیده
We address the impact of a too short cyclic prefix on multicarrier systems such as Orthogonal Frequency Division Multiplex (OFDM) and Discrete MultiTone (DMT). The main result is that the intersymbol interference (ISI) and intercarrier interference (ICI) may be spectrally concentrated and analytical expressions showing this are given. A practical implication is, e.g., that the cyclic prefix in some xDSL systems can be surprisingly short, as shown in one example of ADSL transmission. Keywords— Intersymbol interference (ISI), intercarrier interference (ICI), multicarrier transmission, cyclic prefix, time-domain equalization.
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