面向火星临近空间时变信道的文件可靠传输机理

项目名称： 面向火星临近空间时变信道的文件可靠传输机理

项目编号： No.61201144

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 电子学与信息系统

项目作者： 焦健

作者单位： 哈尔滨工业大学

项目金额： 27万元

中文摘要： 火星探测任务极远的通信距离和复杂的临近空间环境使得表面探测设备无法直接向地球返回探测信息，需要构建火星中继轨道器构建临近空间网络，以中继存储转发的容迟网络体制传输数据文件。而火星临近空间网络的稀疏节点大范围高速移动，同时对文件可靠传输和节点存储资源提出了挑战。深空弱链路的大传播时延以及高误码率，使得传统的深空信道编码和确认重传机制无法满足未来深空探测的需求。随着面向传输层文件分组的长纠删码技术兴起，课题以保障火星临近空间文件可靠传输为切入点，首先对火星临近空间时变信道建模并研究统计特性，以获得节点间的最大吞吐量期望策略；然后针对以火星中继轨道器划分开的两段中继链路，分别设计匹配分段链路质量的差异和设备能力的长纠删编码并与相应的深空容迟网络下存储转发体制的协议层进行联合优化。在保障火星临近空间链路传输性能的同时，保障节点存储能力和资源利用率，并建立仿真验证平台修改和完善上述算法。

中文关键词： 星际互联网；火星临近空间网络；时变信道；文件传输；纠删编码

英文摘要： While the extremely long distance between Mars to Earth and sophisticated proximity space environment, the Martian surface detectors are unable to communicate directly to Earth. In order to overcome these constraints, the Mars Proximity Networks (MPN) is proposed, which have utilized store-and-forward communications system under Delay Tolerant Network (DTN) to increase data return from resource constrained landers. The sparsity and high-speed mobility in a large scale of MPN nodes, have challenged the reliable file delivery and buffer management simultaneity. The current deep space channel coding and conventional ARQ schemes are underperforming, where the high error bit rate and huge propagation delay in MPN environment, and spacecraft storing capabilities limitations. It motivated for using long erasure coding （LEC） systems in the transmission protocol level to provide a further level of protection with respect to conventional bit-level codes. The proposal is focus on the reliable file delivery over MPN, the Mars proximity channel and the statistics of the time-varying need to be researched firstly, to maximize the number of successfully transmitted bits. As Mars obiter divided the two different relay link, the LEC schemes need to be design separately to match the different quality of the link and equipment cap

英文关键词： Interplanetary internet；Mars proximity networks；time-varying channel；file delivery；erasure codes