A large number of papers are now appearing on sixth-generation (6G) wireless systems, covering different aspects, ranging from vision, architecture, applications, and technology breakthroughs. With cellular systems in mind, this paper presents six critical, yet fundamental challenges that must be overcome before development and deployment of 6G systems. These include: Opening the sub-terahertz (sub-THz) spectrum for increased bandwidths and the ability to utilize these bandwidths, pushing the limits of semiconductor technologies for operation within the sub-THz bands, transceiver design and architectures to realize the high peak data rates, and realizations of sub-millisecond latencies at the network-level to achieve the 6G key performance indicators. Additionally, since 6G systems will not be introduced in a green fields environment, backwards compatibility with existing systems is discussed. Where possible, we present practical solutions to realize the identified challenges.

翻译：目前,关于第六代(6G)无线系统的大量论文正在出现,涉及不同方面,包括愿景、结构、应用和技术突破。考虑到蜂窝系统,本文件提出了在开发和部署6G系统之前必须克服的六大关键但根本性挑战。其中包括:打开地表下频谱,增加带宽,提高利用这些带宽的能力,将半导体技术的极限推到次级THz带内操作,使半导体设计和结构实现高峰值数据率,实现网络一级的次级延迟,以实现6G关键业绩指标。此外,由于6G系统不会在绿色田地环境中引入,因此讨论了与现有系统的逆向兼容性。我们尽可能提出实现已查明挑战的实际解决办法。