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arXiv · 2311.11416

Rethinking Integrated Sensing and Communication: When Near Field Meets Wideband

Zhaolin Wang·Xidong Mu·Yuanwei Liu
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Abstract

This article revisits integrated sensing and communication (ISAC) systems that operate in the near-field region of large antenna arrays while utilizing large bandwidths. The article first describes the basic characteristics of a wideband sensing and communication (S&C) channel, highlighting the key changes that occur during the transition from the far-field to the near-field region, namely strong angular delay correlations and non-uniform Doppler frequencies. It is then revealed that the near-field effect can facilitate wideband-like S&C functionality, leading to efficient signal multiplexing and accurate distance sensing, and making large antenna arrays a viable alternative to large bandwidths. In addition, new capabilities for Doppler-domain signal multiplexing and velocity sensing enabled by non-uniform Doppler frequencies, which cannot be achieved by extending the bandwidth alone, are presented. Motivated by these results, several paradigm shifts required to leverage the full potential of near-field wideband ISAC systems are discussed, with particular emphasis on spectrum allocation, antenna array arrangement, transceiver architecture, and waveform design.

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Zhaolin Wang, Xidong Mu, Yuanwei Liu. 2023-11-19. Rethinking Integrated Sensing and Communication: When Near Field Meets Wideband. https://doi.org/10.1109/mcom.001.2300666

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