Читать книгу Shaping Future 6G Networks - Группа авторов - Страница 24

Every new mobile generation features a new radio technology, which typically pushes for higher frequencies and, thanks to new coding and signal processing algorithms, enables much higher data rates and communication capacities to mobile users. In city centers, the deployment of new antenna systems for ever smaller cell sizes operating in ever higher frequencies is facing limitations with signal distribution through walls and windows, representing big challenges. Chapter 6 provides an overview of the development of new reflective materials to enhance coverage of urban areas, introducing the technology and the challenges of reconfigurable intelligent surfaces (RIS) for smart radio environments.

In 6G, terahertz (THz) communications represent this next big radio access network innovation. Chapter 6 describes the new technical capabilities and the research challenges to be mastered to exploit these capabilities. In particular, THz base stations will enable the seamless integration of sensing, localization, and communications, making new types of applications possible. At the same time, they put immense requirements on the core network to utilize these new capabilities.

While THz access networks feature small cell sizes and are likely used for indoor use cases, satellite networks have already gained momentum in the context of 5G evolution for outdoor coverage in rural environments, the maritime environment, and the sky. Besides satellites at different orbit levels, drones and high‐altitude platforms have also emerged as so‐called non‐terrestrial networks in the recent past. The authors of Chapter 8 address opportunities and technical challenges to master the upcoming 6G network architectures, including the need for new mechanisms for dynamic access and backhaul network integration, as well as challenges in roaming and handovers in between moving cells and networks.