基于多业务调度的DTN海上宽带通信网络资源分配算法研究

The low-cost and high-wideband emerging maritime wideband communication networks could intrinsically provide tremendous changes for maritime communication, clearing the way of replacing of current maritime satellite system. The applicant plans to apply Delay-Tolerant Networking (DTN), cooperative technology and green-energy communication technolgy to maritime wideband network innovatively, investigating the optimal resource allocation issues of heterogeneous services in uploading and downloading process respectively, while solving the current shortcoming of maritime wideband communication efficiently. The specific schemes include: (1) Time-capacity mapping is utilized effectively to transform the original scenario with time-based intermittent network connectivity into a virtually cumulative-capacity-based continuous scenario. The time-capacity mapping based two phase (TMTP) algorithm and adaptive maximum weight 2-independent set in interval graph algorithm will be proposed to address the resource allocation issue for multi-vessel cooperative transmission scenario; (2) Based on green energy buffer model, which resorts to G/G/1 queue to model the energy buffer, resource management scheme is designed to shift from energy efficiency to energy sustainability. The transient states of energy depletion duration, maximum carry delay and resource allocation algorithms can be obtained by utilizing diffusion approximation and leaky bucket theory; and (3) Towards the link with bottleneck between backbone network and base stations, a service pre-downloading mechanism is implemented. Meanwhile, the optimal resource allocation and double-loop MAC scheduling scheme are investigated accordingly. This project is meant as a petri dish to provide valuable theoretical guidance and technical support of planning and cost-performance evaluation for future maritime wideband networks.

构建低成本，高带宽的海上宽带通信网络将取代现行卫星通信系统，带来海上通信巨大变革。本项目创新性地将DTN延迟容忍网络、协作技术、绿色通信技术应用到海上宽带系统中，研究上传及下载过程的多业务资源优化分配问题,弥补目前海上宽带通信资源分配研究空白。具体方案：（1）采用时间-容量映射方法将时间上的不连续转换为累积容量上的连续，解决DTN网络连接中断问题。针对多船协作场景，提出二阶段容量最大化算法、间隔图n个最大权重集合改进算法；（2）基于G/G/1模型进行能量缓存器充放电过程分析，将海上绿色通信中能量有效性问题转化为能量可持续性问题。扩散近似理论、令牌漏桶理论都将应用于能量损耗周期、最大延迟周期分析及资源分配算法；（3）为解决主干网与基站连接的传输“瓶颈”现象，实施基于信息预下载的协作下载模型资源分配及双环MAC调度机制。课题将为构建海上宽带系统前期规划和成本性能估算提供理论依据和技术支撑。

构建低成本，高带宽的“海上高速公路”是面向海事界提出的E-Navigation战略，适应目前航海领域业务遇险、紧急、安全以及常规通信、提供更有吸引力的业务需求的重要举措。以应对未来海事通信环境中各种复杂的环境和任务，带来航海模式更安全更高效的转变，也将宽带通信从陆地扩展到海洋,实现未来智能无人船舶的重要基础保障。本项目创新性地将DTN延迟容忍网络、协作技术、绿色通信技术应用到海上宽带系统中，研究上传及下载过程的多业务资源优化分配问题以及安全问题,弥补了目前海上宽带通信资源分配研究空白。具体方案为：（1）基于4G/5G技术、协作技术、WiMAX技术、DTN技术以及绿色通信技术构建海上宽带网络架构；（2）基于DTN技术的海上宽带系统资源优化分配研究。采用时间-容量映射方法将时间上的不连续转换为累积容量上的连续，解决DTN网络连接中断问题。针对多船协作场景，提出二阶段容量最大化算法、间隔图n个最大权重集合改进算法；（3）海上绿色宽带通信资源优化分配研究。基于G/G/1模型进行能量缓存器充放电过程分析，基于扩散近似理论、令牌漏桶理论将海上绿色通信中能量有效性问题转化为能量可持续性问题；（4）为解决主干网与基站连接的传输“瓶颈”现象，进行基于信息预下载的协作下载模型资源分配及双环MAC调度机制。（5）海上通信网络中船队群通信的安全认证协议研究。采用基于椭圆曲线密码体制 (Elliptic Curve Cryptosystems) 的DH (Diffie-Hellman) 密钥交换协议 (ECDH) 提供前向安全性，提高认证的效率，以克服海上军事群组用户隐私易泄露、中间人攻击等安全问题。课题将为构建海上宽带系统前期规划和成本性能估算提供理论依据和技术支撑，使我国海事信息物理融合系统建设方面达到国际先进水平，较大程度上促进我国海洋经济的开发与发展。