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arXiv · 2308.04418

Near-field 6G Networks: Why Mobile Terahertz Communications MUST Operate in the Near Field

Vitaly Petrov·Josep Miquel Jornet·Arjun Singh
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Abstract

Near-field mobile terahertz (THz) communications is one of the candidate enablers for high-rate wireless data exchange in sixth-generation (6G) networks. However, operating in the THz near field brings both attractive opportunities and severe challenges. Hence, it becomes of interest to explore if it is possible to design a realistic mobile THz communication system without working in the THz near field. To answer this question, a mathematical framework is presented modeling a mobile THz link that works exclusively in the far field. The study leads to an interesting theoretical conclusion: while the actual frequency is of (almost) no interest, such a system must operate over a limited bandwidth not exceeding a certain threshold. It is then numerically shown that operating only in the far field imposes stringent limitations on mobile THz communications, thus making them less attractive to prospective high-rate services. In contrast, it is shown that a stationary THz link can still be broadband even when staying exclusively in the THz far field. Hence, broadband mobile THz communications MUST be near-field, while broadband stationary THz links do not have to.

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Vitaly Petrov, Josep Miquel Jornet, Arjun Singh. 2023-08-08. Near-field 6G Networks: Why Mobile Terahertz Communications MUST Operate in the Near Field. https://arxiv.org/abs/2308.04418

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