Near-Field Signal Processing: Unleashing the power of proximity

Beam pattern; Communication environments; Electromagnetic propagation; Near field signals; Near fields; Power; Remote-sensing; Research interests; Signal-processing; Wireless communications; Signal Processing; Electrical and Electronic Engineering; Applied Mathematics; Wireless communication; Location awareness; Training; Array signal processing; Ultraviolet sources; Optics; Acoustic arrays; Acoustics; Sensors; Noise measurement

Abstract :

[en] After nearly a century of specialized applications in optics, remote sensing, and acoustics, the near-field (NF) electromagnetic (EM) propagation zone is experiencing a resurgence in research interest. This renewed attention is fueled by the emergence of promising applications in various fields, such as wireless communications, holography, medical imaging, and quantum-inspired systems. Signal processing within NF sensing and wireless communications environments entails addressing issues related to extended scatterers, range-dependent beampatterns, spherical wavefronts, mutual coupling effects, and the presence of both reactive and radiative fields. Recent investigations have focused on these aspects in the context of extremely large arrays and wide bandwidths, giving rise to novel challenges in channel estimation, beamforming, beam training, sensing, and localization. While NF optics has a longstanding history, advancements in NF phase retrieval (PR) techniques and their applications have lately garnered significant research attention. Similarly, utilizing NF localization with acoustic arrays represents a contemporary extension of established principles in NF acoustic array signal processing. This article aims to provide an overview of state-of-the-art signal processing techniques within the NF domain, offering a comprehensive perspective on recent advances in diverse applications.

Disciplines :

Computer science

Author, co-author :

Elbir, Ahmet M. ; Istinye University, Istanbul, Turkey

Demir, Ozlem Tugfe ; Middle East Technical University, Ankara, Turkey ; TOBB University of Economics and Technology, Turkey

Mishra, Kumar Vijay ; United States Army Research Laboratory, Adelphi, United States

CHATZINOTAS, Symeon ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom ; College of Electronics & Information, Kyung Hee University, Yongin-si, South Korea

Haardt, Martin ; Ilmenau University of Technology, Ilmenau, Germany

External co-authors :

yes

Language :

English

Title :

Near-Field Signal Processing: Unleashing the power of proximity

Publication date :

20 March 2025

Journal title :

IEEE Signal Processing Magazine

ISSN :

1053-5888

eISSN :

1558-0792

Publisher :

Institute of Electrical and Electronics Engineers Inc.

Volume :

Issue :

Pages :

20 - 32

Peer reviewed :

Peer Reviewed verified by ORBi

Additional URL :

http://xplorestaging.ieee.org/ielx8/79/10934750/10934794.pdf?arnumber=10934794

Available on ORBilu :

since 14 November 2025

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