Service Procedures for Providing Dual Steer between TN-NTN

This paper considers a method for providing service continuity to users between a terrestrial network (TN) and a non-terrestrial network (NTN) based on dual steer discussed in 3GPP standardizations groups. In particular, we focus on the interworking between radio access network and core network when the wireless channel quality of TN or NTN is deteriorated. For this situation, we newly propose detailed TN-NTN dual steer procedures by considering the variable radio channel.