NG‐RAN Evolution

This chapter describes some NG‐Radio Access Network (5G‐RAN) evolution paths, which will help expanding 5G networks into new market segments and new deployment options. It defines two important NG‐RAN architecture enhancements: relays and satellite. First, the chapter describes the Integrated Access‐Backhaul (IAB) architecture and then elaborates on the design decisions made to accommodate multi‐hop transport, Quality of Service, and spectrally efficient resource sharing between backhauling and access. IAB introduces wireless relaying to 5G. Prior to 5G, 3GPP networks were traditionally designed to support terrestrial mobile networks. 3GPP conducted a number of studies in Release‐15 and Release‐16 for the support of non‐terrestrial network (NTN) connectivity and committed to specify enhancements needed for NTN in Release‐17. The chapter further highlights critical factors to be considered such as flow and congestion control, duplexing constraints, cross‐link interference, and inter‐node time synchronization. Finally, it discusses autonomous network integration of IAB nodes and dynamic topology changes.