Patent
Efficient employment of digital upsampling using IFFT in OFDM systems for simpler analog filtering
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TLDR
In this article, the NL point IFFT is further optimized by exploiting the fact that (N−1) L of the frequency domain symbols are zero, which enables an embodiment that consists of a pre-processor that multiplies the input samples by complex phase factors, followed by L point IffTs.Abstract:
Systems and methods are provided for transmitting OFDM information via IFFT up-sampling components that transmit data at a higher sampling rate than conventional systems to simplify filter requirements and mitigate leakage between symbols. In one embodiment, an NL point IFFT is performed on a zero inserted set of frequency domain symbols. In another embodiment, the NL point IFFT is further optimized by exploiting the fact that (N−1) L of the frequency domain symbols are zero. This enables an embodiment that consists of a pre-processor that multiplies the input samples by complex phase factors, followed by L point IFFTs.read more
Citations
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References
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Journal ArticleDOI
Fast fourier transforms: a tutorial review and a state of the art
Pierre Duhamel,Martin Vetterli +1 more
TL;DR: Note: V. Madisetti, D. B. Williams, Eds.
Patent
Transmission and reception in a hostile interference environment
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System and method of signal wave shaping for spectrum control of an ofdm signal
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Patent
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