面向低轨卫星互联网的随机接入前导码传输技术  

Investigation of Preamble Transmissions in Random Access Procedure for LEO Satellite Networks

作　　者：张洪铭 彭木根[1] 朱亮 冯兆振 周殷喆 邱慧贞 张世杰 ZHANG Hongming;PENG Mugen;ZHU Liang;FENG Zhaozhen;ZHOU Yinzhe;QIU Huizhen;ZHANG Shijie(School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China;Galaxy Aerospace(Beijing)Technology Co.,Ltd.,Beijing 100089,China)

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876 [2]银河航天(北京)科技有限公司,北京100089

出　　处：《无线电通信技术》2023年第3期478-488,共11页Radio Communications Technology

基　　金：北京市科技计划课题(Z211100004421017)。

摘　　要：围绕低轨卫星随机接入过程中前导码传输性能开展研究,在对现有基于Zadoff-Chu(ZC)序列的两种前导码设计方案基础上,提出一个三级ZC根序列级联的前导码设计方法,并给出了复杂度分析结果。此外,在考虑离散傅里叶变换扩展正交频分复用(Discrete Fourier Transform spread OFDM,DFT-s-OFDM)波形传输的情况下,对低轨卫星随机接入过程前导码检测性能开展了系统级仿真。通过仿真首先探明了不同类型前导码进行峰值检测时所具有的最优检测阈值,其次探究了不同多普勒频移和多用户干扰对前导码检测性能的作用机理,最后分析了不同天气条件对多用户前导码检测性能的影响。上述研究显示采用多个ZC根序列级联的方法可显著提高低轨卫星随机接入用户的数量,但复杂度较高,且受多用户干扰和多普勒频移的影响,该方法的检测性能受限。In this paper,preamble transmission performance is considered in random access procedure for LEO satellite networks,where a 3-level cascaded Zadoff-Chu(ZC)sequence is proposed based on existing ZC-based preamble design.Moreover,the corresponding computational complexity is analyzed.By considering Discrete Fourier Transform spread OFDM(DFT-s-OFDM),system level simulations are performed for three types preamble design in random access procedure for LEO satellite networks.This paper first given the optimal threshold values for different types of preambles,and then,analysis the effect of Doppler shift and multi-user interference on preamble detection performance.Finally,the effect of weather conditions on preamble detection is evaluated.Our studies have shown that the design of high level cascaded ZC sequence is capable of increasing the maximum random number of random access users,whilst it suffers from high computation complexity,and affected by multi-user interference and autocorrelation,the attainable preamble detection performance is limited.

关 键 词：低轨卫星互联网 随机接入过程 前导码 多普勒频移 ZADOFF-CHU序列 DFT-S-OFDM 

分 类 号：TN919.23[电子电信—通信与信息系统]