HLA的实时性扩展

高层体系结构（HLA）面临的一个主要问题是其实时性差。不能满足实时分布式交互仿真的需求。文章首先分析了HLA在支持实时分布式仿真方面存在的不足，然后利用硬件时钟同步技术和绝对时戳机制，对HLA的联邦成员规则、接口规范和对象模型模板进行了实时性扩展，并与其它相关的扩展方案进行了对比分析，结果表明文中提出的方案保证了扩展后实时HLA的后向兼容性和联邦成员的高可移植性，并且保持了HLA时间管理服务的透明性。最后，该文提出了相应的网络时钟同步方案和软同步算法，该时钟同步算法在局域网环境中具有很高的精度。

Real-Time Extension to HLA

One of the major disadvantages of HLA (High Level Architecture) is its poor real- time performance, which makes HLA fail in real- time distributed - interactive simulation applications. In this paper, the limits of HLA in real - time distributed- interactive simulations are first analyzed. Then, based on the mechanism of absolute timestamp and hardware clock synchronization, a practical real- time extension to HLA is proposed, including HLA rules, interface specification, and object model template. Furthermore, other related work is also reviewed and compared, which demonstrates that the real- time extension schema proposed in this paper provides the real- time extended HLA with full backward compatibility and high federate portability, and also keeps the HLA time management service transparent to users. Finally, an algorithm of software network clock synchronization with high accuracy in LAN is introduced.