【作者】 高闻天； 谢文轩； 高仕鹏； 朱立东；

【Author】 Gao Wentian;Xie Wenxuan;Gao Shipeng;Zhu Lidong;National Key Laboratory of Wireless Communications ,University of Electronic Science and Technology of China;Shenzhen Institute for Advanced Study,University of Electronic Science and Technology of China;

【机构】 电子科技大学通信抗干扰全国重点实验室； 电子科技大学(深圳)高等研究院；

【摘要】 本文深入探讨了5G随机接入方法在卫星通信中的应用,特别是针对低轨卫星系统。随机接入技术是用户与卫星通信系统建立联系的关键环节,对于实现地面与卫星通信网络的融合至关重要。本文分析了低轨卫星通信系统的特点,包括多普勒频偏、自由空间传播损耗和多径效应等,并探讨了随机接入的处理流程和时序模型。结合低轨卫星信道的独特性和随机接入信号的特性,本文建立了用户随机接入模型,并对小区选择前的下行同步过程和物理下行共享信道(PDSCH)的随机接入信号性能进行了评估。仿真结果表明,经过适当的调整,地面网络的5G NR随机接入流程可以有效应用于卫星通信场景中。更多还原

【Abstract】 This paper deeply discusses the application of 5G random access method in satellite communications,especially for low-earth orbit satellite systems.Random access technology is a key part for users to establish connection with satellite communication systems,and is essential for the integration of terrestrial and satellite communication networks.In this paper,the characteristics of low-earth orbit satellite communication systems are analyzed,including Doppler frequency offset,free-space propagation loss and multipath effect,and the processing flow and timing model of random access are discussed.Combined with the uniqueness of the LEO satellite channel and the characteristics of the random access signal,this paper establishes a user random access model,and evaluates the downlink synchronization process before cell selection and the random access signal performance of the physical downlink shared channel(PDSCH).The simulation results show that the 5G NR random access process of the terrestrial network can be effectively applied to the satellite communication scenario after appropriate adjustment.更多还原