US 12,113,606 B2
Methods and systems for mobility management in non-terrestrial networks
Xiaojuan Shi, Guangdong (CN); Jianwu Dou, Guangdong (CN); Nan Zhang, Guangdong (CN); Wei Cao, Guangdong (CN); He Huang, Guangdong (CN); and Li Yang, Guangdong (CN)
Assigned to ZTE CORPORATION, Guangdong (CN)
Filed by ZTE CORPORATION, Guangdong (CN)
Filed on Mar. 25, 2021, as Appl. No. 17/212,594.
Application 17/212,594 is a continuation of application No. PCT/CN2018/107971, filed on Sep. 27, 2018.
Prior Publication US 2021/0314060 A1, Oct. 7, 2021
Int. Cl. H04B 7/185 (2006.01); H04W 8/08 (2009.01)
CPC H04B 7/18541 (2013.01) [H04B 7/18547 (2013.01); H04W 8/08 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method performed by a first communication node, the method comprising:
during a first time period, communicating with a non-terrestrial communication node utilizing a first communication link, wherein the non-terrestrial communication node provides at least one geographic cell in which a user equipment device (UE) is present during the first time period;
during a second time period,
communicating with a second communication node utilizing a second communication link,
establishing a third communication link between the non-terrestrial communication node and the second communication node, and not utilizing the first communication link during the second time period, and wherein the UE remains within the at least one geographic cell during the second time period,
receiving downlink data from a core network,
performing service data adaptation protocol (SDAP) processing and packet data convergence protocol (PDCP) processing on the downlink data to provide processed downlink data, and
transmitting the processed downlink data to the second communication node, wherein the second communication node is configured to forward the processed downlink data to the non-terrestrial communication node without further SDAP and PDCP processing by performing only data relaying between the first communication node and the non-terrestrial communication node; and
determining to maintain the first communication node as an anchor node for communications between the core network and the UE during both the first and second time periods, wherein security keys associated with the UE remain unchanged during both the first and second time periods.