Low Latency MCS Design for LEO Satellite Communication Based on 5G

With the development of mobile communication, satellite communication technology has met new opportunities. In the future, the joint development of satellite and 5th Generation (5G) is the general trend. However, the characteristics of the low earth orbit (LEO) satellite and the different transmission environment will bring huge challenges to the current 5G technical standards. In this paper, we first carry out link budget for LEO satellite under Non-Terrestrial Network (NTN) channel. Then, we design a 21 level Modulation and Coding Scheme (MCS) combined of modulation mode of Digital Video Broadcasting (DVB) and the encoding mode of 5G. Inspired by the analysis of retransmission times and initial block error rate (BLER), we simulate signal noise ratio (SNR) thresholds under different target BLER and obtain a MCS table with target BLER of 10%, 1% and 0.1%. Subsequently, the retransmission times and throughput of the MCS table are simulated. Simulation results show that the designed MCS tables have better reliability and lower feedback delay, which improves throughput for LEO communication system.