TY  - JOUR
T1  - Optimal Low Earth Orbit Satellite Selection Algorithm to Reduce Handover Failure Rate in NTN
AU  - Seo, Kyunghee 
AU  - Kwon, Jinsol 
AU  - Baek, Hoki 
JO  - The Journal of Korean Institute of Communications and Information Sciences
PY  - 2024
DA  - 2024/1/1
DO  - 10.7840/kics.2024.49.11.1574
KW  - Non-terrestrial Networks
KW  - Baseline handover
KW  - Conditional handover
KW  - Optimization
AB  - LEO satellites provide low latency and high data transmission speeds in NTN, ensuring reliable coverage for UE over wide areas. However, due to their high speed of 7-8 km/s, frequent handovers are required as the communication links with LEO satellites change often. BHO is not suitable for satellite communications due to unnecessary handovers and increased energy consumption. Conditional handover, specified in 3GPP Release 16, uses various trigger conditions to maintain stable network connections despite the rapid movement and irregular cell coverage of LEO satellites. This paper proposes an algorithm for selecting the optimal target satellite to minimize handover failure probability and provide uninterrupted service to UE. The proposed algorithm considers the available resources of the satellites in addition to existing research, reducing handover failures due to resource shortages. The proposed optimization algorithm and reward function demonstrate superior performance compared to existing algorithms.