一种基于CRDSA的VDE-SAT随机接入方法-《计算机技术与发展》

文章信息/Info

作者:: 王志文1; 杨树树2; 唐寅1; 谢飞宇1; 陈春婷1; 1. 成都信息工程大学计算机学院,四川成都 610225;2. 南京电子设备研究所,江苏南京 210007

Author(s):: WANG Zhi-wen1; YANG Shu-shu2; TANG Yin1; XIE Fei-yu1; CHEN Chun-ting1; 1. School of Computer Science,Chengdu University of Information Technology,Chengdu 610225,China;2. Nanjing Electronic Equipment Research Institute,Nanjing 210007,China

Keywords:: VHF data exchange-satellite; multiple-copy technology; interference elimination; direct sequence spread spectrum; power di-versity

摘要:: 甚高频数据交换-卫星部分(VHF Data Exchange-Satellite,VDE-SAT)是下一代海事通讯系统甚高频数据交换系统(VHF Data Exchange System,VDES)的关键组成部分,用于实现航海船站与海事卫星以及航海船站间的相互通信和数据传输,其链路层接入性能对于 VDES 的实际应用效果有着重要影响。针对当前实际应用中航海船站随机接入 VDES 系统容易出现峰值吞吐量较低和线性工作区较短的问题,该文在深入分析国际电信联盟制定的 ITU-R M. 2092 标准规范和航海船站接入 VDE-SAT 的技术特性,以及现有无线网络随机接入协议的基础上,提出一种适用于 VDE-SAT 的基于功率分集和直接序列扩频的竞争解决分集时隙 ALOHA( Power Diversity and Direct Sequence Spread Spectrum CRDSA,PD - DS -CRDSA)方法。该方法在传统无线网络竞争解决分集时隙 ALOHA(Contention Resolution Diversity Slotted ALOHA,CRDSA)算法的基础上,通过采用多副本技术和连续干扰消除技术提高数据包成功解码率,同时引入功率分集和直接序列扩频技术,在一定程度上消除了传统 CRDSA 算法容易出现的“环路”问题。实验仿真结果表明,该方法在提高 VDE-SAT 随机接入的峰值吞吐量,延长线性工作区和降低数据包碰撞率等方面有较好表现。

Abstract:: The VHF Data Exchange-Satellite (VDE-SAT) plays a crucial role in the VHF Data Exchange System (VDES),the next-generation maritime communication system facilitating communication between maritime satellites and ship stations. The performance of link layer access significantly influences the practical effectiveness of VDES. Addressing the challenge of low peak throughput and limited linear working range in current maritime ship station applications of random access to the VDES system, we conduct a comprehensive analysis of the ITU-R M. 2092 standard specifications and maritime ship station issues. Leveraging the technical features of VDE-SAT access and existing random access protocols in wireless networks,we propose the Power Diversity and Direct Sequence Spread Spectrum Contention Resolution Diversity Slotted ALOHA (PD-DS-CRDSA) method for VDE-SAT. This method builds upon the traditional wireless network Contention Resolution Diversity Slotted ALOHA (CRDSA) algorithm,enhancing performance through multi-copy technology and continuous interference cancellation. By incorporating power diversity and direct sequence spread spectrum technology,the proposed approach mitigates the ’loop’ problem inherent in the traditional CRDSA algorithm. Experimental simulations demonstrate the proposed method is effective in improving the peak throughput of VDE - SAT random access, extending the linear working area and reducing the packet collision rate.