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arXiv · 2105.13596

A Low-Complexity Method for FFT-based OFDM Sensing

Kai Wu·J. Andrew Zhang·Xiaojing Huang·Y. Jay Guo
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Abstract

OFDM sensing is gaining increasing popularity in wideband radar applications as well as in joint communication and radar/radio sensing (JCAS). As JCAS will potentially be integrated into future mobile networks where OFDM is crucial, OFDM sensing is envisioned to be ubiquitously deployed. A fast Fourier transform (FFT) based OFDM sensing (FOS) method was proposed a decade ago and has been regarded as a de facto standard given its simplicity. In this article, we introduce an easy trick -- a pre-processing on target echo -- to further reduce the computational complexity of FOS without degrading key sensing performance. Underlying the trick is a newly disclosed feature of the target echo in OFDM sensing which, to the best of our knowledge, has not been effectively exploited yet.

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BibTeXRIS

Kai Wu, J. Andrew Zhang, Xiaojing Huang, Y. Jay Guo. 2021-05-28. A Low-Complexity Method for FFT-based OFDM Sensing. https://arxiv.org/abs/2105.13596

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