低轨卫星通信系统的前导序列设计  

Preamble Design for Low Earth Orbit Communication Systems

作　　者：朱剑锋 孙耀华 彭木根[1] ZHU Jianfeng;SUN Yaohua;PENG Mugen(School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876

出　　处：《北京邮电大学学报》2022年第6期75-81,共7页Journal of Beijing University of Posts and Telecommunications

基　　金：国家重点研发计划项目(2020YFB1806703);国家自然科学基金项目(62001053);北京市新一代信息通信技术创新项目(Z211100004421017)。

摘　　要：由于低轨卫星波束小区最大前导到达时间差远大于第5代移动通信系统(5G)地面小区的最大前导到达时间差,在后5G低轨卫星通信系统中直接应用现有5G前导序列设计方案易导致定时提前估计失败。为此,通过分析两步定时提前估计流程和前导序列间干扰,提出一种增强前导序列设计方案,包括灵活级联前导子序列以及在子序列间进行差异化功率分配。仿真结果表明,当接入用户数为32且信噪比为-10 dB时,所提方案比现有方案能显著降低前导漏检率和用户随机接入失败的可能性。Since maximal preamble arrival time difference is much more significant in satellite beam cells than that in terrestrial case, current preamble formats in the fifth generation of mobile communications system(5 G) cannot be directly applied to beyond 5 G low earth orbit satellite networks, which can easily cause timing advance(TA) estimation failures. To cope with this challenge, by investigating 2-step TA estimation procedure and inter-preamble interference, an enhanced preamble format design scheme is proposed, whose core idea lies in flexible cascading of sub-sequences and differential power allocation among them. Simulation results show that when 32 users access and signal to noise ratio is-10 dB, our proposal can achieve a much lower missed detection rate of preamble and decrease the failure probability of random access, compared with benchmarks.

关 键 词：低轨卫星 随机接入 前导序列设计 定时提前估计 

分 类 号：TN927.2[电子电信—通信与信息系统]