Field Trials for 5G System Roaming as Multi-operator Network Sharing Scheme — User Mobility Problems and Solutions

In order to save capital as well as operational expenditure, many mobile operators choose 5G co-construction and sharing. 5G system roaming can be considered as one of the network sharing schemes, which is suitable for rural areas. In this paper we introduce the networking architecture and all relevant interfaces of 5G system roaming (home routed), and design field trials to verify the feasibility of the new network sharing scheme. Because the inter-RAT and inter-operator N26 interface has not been opened, some problems of mobility, in particular for voice and video call services arise. For each problem, solutions on the wireless side are proposed and tested, which are proven to be effective in addressing the above issues.