5G Integrated User Downlink Adaptive Transmission Scheme for Low Earth Orbit Satellite Internet Access Network

Abstract

After the low-earth orbit (LEO) satellite Internet has gone through the two stages of competing with the terrestrial network and supplementing the terrestrial network, it has begun to enter the third stage of constructing the satellite-ground integrated network with the terrestrial network to provide seamless global coverage. 5G New Radio (NR) is one of the core enabling technologies of the third stage of satellite Internet. This paper focuses on how to make full use of the power and bandwidth resources on the LEO satellite by using adaptive transmission scheme to maximize the throughput of the user downlink based on 5G NR. To solve the problem that the ultra-long propagation delay, outdated channel state information (CSI) and dynamic multi-scenario of LEO satellite will lead to the high implementation cost and greatly reduced performance when applied the 5G adaptive transmission scheme to LEO satellites, we optimized the adaptive transmission scheme of 5G NR based LEO satellite from multiple dimensions such as adaptive transmission process, signal to noise ratio (SNR) prediction and modulation and coding scheme (MCS) adaptive switching strategy. The simulation results show that compared with the fixed threshold switching strategy based adaptive transmission scheme, the proposed scheme can improve the average throughput of the system by 26.6% under the dynamic multi-scenario environment served by the LEO satellite.