Rethinking Beam Squint Mitigation in XL-MIMO: The Impact of Practical TTD Constraints

Research output: Contribution to book/Conference proceedings/Anthology/ReportConference contributionContributedpeer-review

Abstract

The integration of extremely large-scale multipleinput multiple-output (XL-MIMO) and ultra wideband (UWB) communications is essential to address the escalating demand for high data rates in sixth generation (6 G) wireless networks. However, the expansion of antenna array apertures and/or signal bandwidth introduces the spatial-wideband effect, resulting in frequency-dependent propagation characteristics and the manifestation of the beam squint phenomenon. To mitigate beam squint, true-time delay (TTD) elements have been proposed as promising hardware solutions. Despite this, most existing TTD-based precoding architectures assume idealized conditions, such as unbounded delay ranges and infinite resolution, which are impractical for real-world implementation. In this context, this paper investigates the performance degradation caused by practical TTD constraints. Simulation results demonstrate that under realistic hardware limitations and a finite number of TTD elements, conventional precoding schemes are insufficient to suppress beam squint in XL-MIMO systems as the antenna count scales. These findings underscore the necessity for hardwareaware TTD precoding designs that can effectively accommodate the constraints of practical implementations.

Details

Original languageEnglish
Title of host publication2025 28th International Workshop on Smart Antennas (WSA)
PublisherIEEE Canada
Pages53-59
Number of pages7
ISBN (electronic)9798350392685
ISBN (print)979-8-3503-9269-2
Publication statusPublished - 18 Sept 2025
Peer-reviewedYes

Workshop

Title28th International Workshop on Smart Antennas
Abbreviated titleWSA 2025
Conference number28
Duration16 - 18 September 2025
Website
Degree of recognitionNational event
LocationFriedrich-Alexander-Universität Erlangen-Nürnberg
CityErlangen
CountryGermany

External IDs

ORCID /0000-0002-0738-556X/work/195440874
ORCID /0000-0002-1315-7635/work/195441932
ORCID /0000-0002-1680-6581/work/195442214
ORCID /0000-0001-7075-8990/work/195442217
Scopus 105022420699

Keywords

Keywords

  • Antenna arrays, Bandwidth, Delay effects, Delays, Finite element analysis, Hardware, Precoding, Prevention and mitigation, Ultra wideband communication, Wireless networks