Principles of the architecture of the fifth generation cellular networks

Abstract

A review of the principles of formation of the architecture of the fifth generation cellular communication standard (5G) has been carried out. The main limitations and principles of 5G architecture implementation are revealed. The main 5G NR protocol stacks are defined, which are divided into three main layers: physical; MAC, RLC, PDCP; RRC, which are represented schematically. The essence of the O-RAN network is described, which offers the possibility of full (or partial) execution of the protocol stack in a remote computing center implemented on a personal computer, due to which the cloud concept of C-RAN (Cloud RAN) is implemented. The current 3GPP 5G architecture is illustrated, highlighting the shortcomings of the architecture shown. The main areas requiring detailed processing include, first of all, the section of protocols between the radio interface and the N2/N3 protocol stack of RAN nodes, which will allow to implement stable access and constant communication in the network, minimizing external influences, and secondly, modification of the user equipment control panel , by controlling the uplink data flow, which will allow the control panel to flexibly connect to various networks such as 5GC, 4G CN, or directly to the Internet. The latest architecture of the fifth generation (5G) cellular standard is presented, which communicates with 5G through a unified interaction object instead of separate interaction functions. A modification of the user equipment control panel is proposed, minimal software changes in the 3GPP 5G architecture are noted, which are easy to implement, and the most important thing in the proposed approach is the absence of changes in the protocol between the user control panel and gNB and 5GC, as well as gNB and 5GC. It is emphasized that the architecture of the fifth generation cellular communication standard RAN 5G has simplified integration with multiple RATs, efficient data flow control in the RAN, the flexibility to connect to any CN or the Internet directly through the RAN based on 4G/5G/Wi-Fi.