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arXiv · 2305.19559

Spatial IDFT for Squint-Free Massive Arrays

Hesham Beshary·Ali Niknejad
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Abstract

This paper presents a novel technique to build squint-free massive phased arrays. This is accomplished by explicitly implementing a spatial IDFT to cancel out the DFT imposed by the array nature which causes beam squint. In addition, the paper analyzes the beam-squint issue, which arises from two mechanisms: the coherent bandwidth limitations and the systematic delay spread in the array. These mechanisms reduce the signal-to-noise ratio and cause inter-symbol interference. This work also highlights the importance of utilizing OFDM modulation to enhance signal quality by mitigating the self-interference issue. A numerical solver is used to simulate and verify the IDFT squint-free implementation and to estimate the signal quality limitations in massive arrays.

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BibTeXRIS

Hesham Beshary, Ali Niknejad. 2023-05-31. Spatial IDFT for Squint-Free Massive Arrays. https://doi.org/10.1109/tcsi.2026.3672668

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