【作者】 黄飞；

【导师】 王跃科；

【作者基本信息】 国防科学技术大学 ， 仪器科学与技术， 2008， 博士

【摘要】 传统仪器面向广域测控应用时,存在体系结构不开放以及缺少测量信息完整性(时间一致性、空间一致性以及溯源一致性)支持等问题。作者所在研究组基于“测量信息完整性”的观点和“开放体系结构”的思路,提出了“网络仪器”的解决方案,以实现仪器资源的开放互联和信息资源的广域共享。由于现有网络交换技术存在数据交换时延不确定的问题,在构建网络仪器时,为了满足探头资源(智能传感器和执行器)的网络接入和时间确定性数据交换的需求,本文引入“测控HUB”这一设备单元,并将其定义为具备时间统一和时间确定性数据交换功能的网络仪器的边界设备。论文以“网络仪器”为背景,围绕“时间确定性”这一核心问题,对测控HUB的结构组成、时间统一、时间确定性数据交换、以及测控HUB的设计实现与性能测试等问题进行了研究,论文主要工作如下:1、从网络仪器需求的角度,阐述了测控HUB的概念与特征,给出了时间确定性数据交换模型;基于网络仪器的体系结构框架以及测控HUB的概念,提出了测控HUB的完整构建方案,对测控HUB及其组成要素(外部端口、内部链路和功能单元)的结构进行了设计。2、从基准时间接入、时间测量和时间传递三个方面对测控HUB中的时间统一技术展开研究。(1)针对多基准时间信号的可信判别问题,提出一种以事件时刻精确测量为基础的通用可信判别方法,解决了现有方法不能同时对周期和非周期时间信号进行可信判别的问题;(2)针对基准时间信号到达等事件发生时刻的精确测量要求,设计了基于统一时间的事件时刻精确测量方法,实现了具有延迟时间自校功能和连续实时测量能力的事件时刻精确测量电路(已申请国家发明专利);(3)针对目前采用“时间同步”策略的时间传递方法存在时间校正误差的问题,提出一种基于“时钟交联”策略的时间传递方法,避免了时间校正环节,从而消除了时间校正的不确定误差,提高了时间传递精度。3、针对测控HUB时间确定性数据交换的需求,在对常规数据交换技术所存在的交换时延不确定问题分析的基础上,提出一种基于时间压力的时间确定性数据交换策略及其最大压力优先(LPQF)调度算法,深入研究了LPQF调度算法的基本原理、数学模型和实现方法,并采用网络微积分理论对LPQF调度算法进行了分析;设计了仿真软件对LPQF调度算法的性能进行验证,结果表明该调度算法相对于现有交换设备的调度算法能够有效保证数据包交换时延的确定性(“基于时间压力的时间确定性数据交换方法及交换装置”已申请国家发明专利)。4、结合卫星导航用户设备测试系统的项目需求,设计实现了测控HUB原型系统;针对测控HUB的性能测试问题,归纳了测控HUB的性能指标系列,并设计了各项性能指标的测试方法;开发了基于多DSP互联的测控HUB性能测试平台,并基于该平台对测控HUB原型系统的性能进行了评估。更多还原

【Abstract】 The main problems existing in traditional instrument for wide-area measure and control application are the absence of an open architecture and measurement information integrity, such as clock synchronization, space consistency and traceability consistency. To solve these problems and realize the wide-area sharing of information resources under an open interconnection of instrument, a solution for the Instrument on Network(ION) is proposed. It is based on the perspective of measurement information integrity and the idea of open architecture. Meanwhile, a nondeterministic data transmission problem appears when using the existing network switching technology to construct the proposed ION. Considering the problems of probe’s network access and data’s deterministic exchange time in the ION, a“Measure-control HUB(MCHUB)”device unit is designed. It is defined as the border device that has the capability of unified time and deterministic switch delay.Based on the background of ION, this dissertation focuses on the core issue of“time deterministic”. The problems included structure and component of the MCHUB, unified time, data deterministic-time exchange, the design, implementation and performance evaluation of MCHUB are studied. The major research efforts include the following aspects.1. Considering the demands of ION, the concept and the characteristic of MCHUB are expounded. Also a deterministic data exchange model is presented. Based on the architecture of ION and the concept of MCHUB, the structure of MCHUB and a constructure design of its components are proposed.2. The unified time internal of MCHUB is researched with respect to benchmark time access, precise time measurement and time transfer.(1) Current existing evaluation methods can not provide the credible discrimination to the periodic time signal and the nonperiodic time signal at the same time. Aiming at the credible discrimination problem for multiple benchmark time signals, an evaluation method based on accurate event-time measurement is proposed. This method realized the simultaneous discrimination of the periodic time signal and the nonperiodic time signal.(2) In order to satisfy the requirement of the accurate measurement of time benchmark signal’s arrival events, a precise measurement method based on unified time is carried out. Also an accurate measurement circuit which has the ability of delay’s self-calibration within delay unit and continuous real-time measurement is designed.(3) A method of time transfer based on“clock jioned”is proposed for the consideration that errors rise during the time transfer process based on the time synchronization. The proposed method eliminates the errors brought by revised clock in course of synchronization and improves the precision of time transfer.3. To satisfy the deterministic data exchanging demand of MCHUB, the data exchange strategy based on the time pressure and schedule algorithm of largest pressure queue first(LPQF) is proposed according to the analysis of the nondeterministic time of conventional data exchange technology. The schedule algorithm of LPQF including basic principle, mathematical model, algorithm design and realization are comprehensively studied. It is analyzed by network calculus theory. To verify the performance of scheduling algorithm, a emulational software is designed. The simulate results show that LPQF guarantees the certainty of deterministic time’s data exchange and hence has better performance than other current algorithms.4. A prototype of MCHUB is designed based on the demand of satellite navigation equipment test system. To evaluate the performance of MCHUB, a series of performance index is concluded. And the test method of performance index is designed. At last, the performance test platform is constructed by multi-DSP’s interconnection. The prototype of MCHUB is evaluated by the performance test platform.更多还原