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arXiv · 2206.05570

A Two-Dimensional FFT Precoded Filter Bank Scheme

R. Pereira Junior·C. A. F. da Rocha·B. S. Chang·D. Le Ruyet
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Abstract

This work proposes a new precoded filter bank (FB) system via a two-dimensional (2D) fast Fourier transform (2D-FFT). Its structure is similar to Orthogonal Time Frequency Space (OTFS) systems, where the OFDM transmitter is changed to a filter bank multi-carrier (FBMC) one, thus obtaining a lower out-of-band emission. The complex orthogonality of the FBMC transmission is guaranteed by using precoding based on a discrete Fourier transform, which is also used to implement the two-dimensional fast Fourier transform. Through the use of a global transmission matrix, we propose a hybrid receiver for the new system. First, a frequency domain equalization is performed, followed by an interference cancellation on the delay-Doppler domain. The simulation results show that the proposed system obtains an error performance similar to other OTFS systems, and superior performance as compared to other precoded FBMC systems.

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BibTeXRIS

R. Pereira Junior, C. A. F. da Rocha, B. S. Chang, D. Le Ruyet. 2022-06-11. A Two-Dimensional FFT Precoded Filter Bank Scheme. https://arxiv.org/abs/2206.05570

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