A Perspective on the Impact of Group Delay Dispersion in Future Terahertz Wireless Systems

TL;DR

This paper examines how group delay dispersion affects future 6G terahertz wireless systems, highlighting challenges, potential benefits, and the role of photonic GDD control devices for system optimization.

Contribution

It provides a comprehensive analysis of GDD sources, experimental validation, and discusses innovative mitigation and utilization strategies, including photonic devices, for 6G systems.

Findings

Atmospheric GDD impacts 6G performance confirmed experimentally.

GDD manipulation strategies have limited effectiveness in 6G.

Leveraging GDD can enhance security and simplify hardware in 6G.

Abstract

This article discusses the challenges and opportunities of managing group delay dispersion (GDD) and its relation to the performance standards of future sixth-generation (6G) wireless communication systems utilizing terahertz frequency waves. The unique susceptibilities of 6G systems to GDD are described, along with a quantitative description of the sources of GDD, including multipath, rough surface scattering, intelligent reflecting surfaces, and propagation through the atmosphere. An experimental case-study is presented that confirms previous models quantifying the impact of atmospheric GDD. Several GDD manipulation strategies are presented illustrating their hindered effectiveness in the 6G context. Conversely, some benefits of leveraging GDD to enhance 6G systems, such as improved security and simplified hardware, are also discussed. Finally, a perspective on using photonic GDD control devices is provided, revealing quantitative benefits that may unburden existing equalization schemes. The article argues that GDD will uniquely and significantly impact some 6G systems, but that its careful consideration along with new mitigation strategies, including photonic devices, will help optimize system performance. The conclusion provides a perspective to guide future research in this area.