低轨卫星星座系统的快速随机接入算法  

A Fast Random Access Algorithm of LEO Satellite Constellation

作　　者：秦兴 冉静 刘芳[1] QIN Xing;RAN Jing;LIU Fang(School of Electronic Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学电子工程学院,北京100876

出　　处：《青岛科技大学学报（自然科学版）》2021年第5期103-110,共8页Journal of Qingdao University of Science and Technology:Natural Science Edition

基　　金：国家自然科学基金项目(61821001).

摘　　要：在低轨卫星星座系统中,针对高动态终端需要快速接入的问题,提出了一种基于增强型冲突解决ALOHA(ECRA,enhan cingcontent resolution ALOHA)改进算法(MECRA,modifiedECRA).该算法利用用户终端会被两颗及以上低轨卫星覆盖的特点,数据包只需发送一次,可被多颗卫星同时接收.在接收端采用滑动窗口确定数据包的位置,并通过迭代干扰消除实现数据包的接收与检测.在此基础上引入区分优先级的接入控制,优化了高动态终端首次接入成功率.通过仿真验证了所提算法在吞吐率和丢包率方面均优于传统ECRA算法,采用优先级接入控制后,高动态终端的首次接入成功率可以达到90%以上.In the low-earth-orbit(LEO) satellite constellation system, aiming at the problem of fast access for highly dynamic terminals, this paper proposes an improved algorithm(MECRA, modified ECRA) of the enhancing content resolution ALOHA(ECRA). This algorithm takes advantage of the feature that the user terminal will be covered by two or more low-orbit satellites. The data packet only needs to be sent once and can be received by multiple satellites at the same time. At the receiving end, a sliding window is used to determine the position of the data packet, and the reception and detection of the data packet is achieved through iterative interference cancellation. On this basis, prioritized access control is introduced to optimize the first access success rate of highly dynamic terminals. It is verified by simulation that the proposed algorithm is superior to the traditional ECRA algorithm in terms of throughput and packet loss rate. After using priority access control, the first access success rate of highly dynamic terminals can reach more than 90%.

关 键 词：低轨星座 高动态终端 随机接入 迭代干扰消除 

分 类 号：TN927[电子电信—通信与信息系统]