DS-CDMA system outer loop power control and improvement for multi-service

When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control （OLPC） technology has to be adopted to enrich the target signal interference ratio （Silt） and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.     

Research on robust fault-tolerant control for networked control system with packet dropout

A kind of networked control system with network-induced delay and packet dropout, modeled on asynchronous dynamical systems was tested, and the integrity design of the networked control system with sensors failures and actuators failures was analyzed using hybrid systems technique based on the robust fault-tolerant control theory. The parametric expression of controller is given based on the feasible solution of linear matrix inequality. The simulation results are provided on the basis of detailed theoretical analysis, which further demonstrate the validity of the proposed schema.     

Performance evaluation from stochastic statecharts repre-sentation of flexible reactive systems：a simulation approach

This paper focuses on the performance analysis of flexible reactive systems. The performance analysis consists of two phases： first system modeling, second performance evalua-tion. The paper models the flexible reactive system by the stochas-tic statecharts method, and uses the simulation method to evalu-ate the performance. To make use of the feature of event-triggered state transitions in the statecharts, a new method of simulation is proposed based on the techniques of the discrete-event system simulation. The new method solves the problem of computer imple-mentation of stochastic events, probabilistic transition, concurrent states, paral el actions, and broadcast communication mechanism in the stochastic statecharts. An example of a flexible manufactur-ing system is presented. The simulation result of the example is consistent with the analytical result, which shows the feasibility of the proposed new simulation method.     

基于KD-DRT的雷达射频信号半实物仿真系统实现

首先介绍了分布实时仿真系统的四层体系结构,从而引出支撑系统KD-DRT;再提出采用这种分层的分布实时仿真技术构建精确制导武器的雷达射频信号半实物仿真系统;对系统模块的层次化分解以及分布系统的时间同步策略进行了分析,最后给出了系统的具体实现结构,验证了KD-DRT针对雷达信号级分布实时仿真的有效性。

Abstract：

4-tier hiberarchy was put forward as the standard architecture of distributed real-time simulation system, and KD-DRT was introduced as a supporting platform. A radar RF signal simulation system for precisely guided missile was constructed based on KD-DRT. The system modules were arranged to different layer according to its time restriction and the time synchronization method of the distributed system was studied. At last, the simulation system was constructed and the efficiency of KD-DRT in simulation of radar signal was proved.     

上行多用户MIMO-OFDMA系统调度与预编码设计

提出了一种基于码书的最大化吞吐量预编码与Round-Robin行列式多用户调度相结合的方案。利用行列式调度算法效用函数以及预编码酉阵码书的特点,两者能够独立设计,同时相互结合提高系统的整体性能。将方案在一个多小区MIMO-OFDMA系统中进行仿真评估,并设计改进的MMSE-SIC接收机。仿真结果表明联合设计方案能够大大增加系统吞吐量,同时改善小区边缘用户的传输性能,有利于公平性的满足。

Abstract：

An uplink multiuser scheduling and precoding scheme was proposed which combined throughput maximization precoding based on the codebook and determinant multiuser scheduling.Through utilizing of the determinant utility function and the unitary codebook,the degisn of the multiuser scheduling and the precoding design could be independent while the combination of which could improve the system performance.The scheme was evaluated in a multi-cell MIMO OFDMA system simulation platform in which a modified MMSE-SIC receiver was implemented.The simulation results show that the design can improve the system throughput greatly and enhance the transmission performance of cell edge users which benefits for the fairness requirement.     

基于BOM的STSS系统仿真设计与实现

以空间跟踪与监视系统（Space Tracking and Surveillance System,STSS）为仿真对象,基于高层体系结构（High Level Architecture,HLA）分布式仿真技术设计、开发STSS仿真系统。分析了STSS技术特点及仿真需求,按照基本对象模型（Base Object Model,BOM）开发标准构建系统的层次化联邦架构,提高了系统开发效率和模型的可重用性。通过对不同场景的多次仿真,初步验证了STSS的性能指标,说明该系统具有良好的适应性。

Abstract：

Based on HLA distributed simulation technology, design and implementation of STSS simulation system, the technical traits of STSS system and demands of simulation were analyzed. According to BOM development standard, a framework in hierarchy of STSS simulation system was constructed, which has effectively improved the efficiency of system realization and the capability of model reuse. By simulating the different scenarios repeatedly, the performance parameter of the STSS simulation system was tentatively verified, and applicability of the simulation system was proved.     

Applying process mining approach to support the verification of a multi-agent system

Using agent development tools to construct an agent-based system is a well applied approach.However,the development tools usually do not have the function to check the feasibility about the workflow of the agent system during it implementation stage.Therefore,to develop an evaluation approach to analyze the feasibility of a developing agent system such that the improper workflow of an agent system can be found in the early design stage is a necessary task to reduce the risk of implementation.In this research,a Petri Net(PN) based three-stage evaluation approach was developed.In the conceptual stage,the pitfall of the current agent system developing process was examined and an improvement analysis process was specified.Then,in the system design stage,an evaluation approach which extracted the process log file from a developing agent system into a PN model in terms of a process mining approach-α algorithm was proposed.This model was simulated in a PN simulation package.The agent system performance was evaluated in terms of analyzing the deadlock phenomena of the PN model.Finally,in the implementation stage,the proposed concept was implemented by using an agent developing tool JADE and a PN simulation tool CPN.An agent-based robotic assembly system was used to examine the possible deadlock of the agent system.     

一种新型UUV半实物仿真系统设计与实现

针对UUV导航与控制系统高精度仿真的需要,设计了一种支持捷联惯导、多普勒测速仪、深度传感器和GPS接收机接入的半实物仿真系统,解决了GPS卫星导航信号仿真、多普勒测速仪水声回波模拟和UUV深浅水航行深度模拟问题,进行了导航与控制系统的半实物仿真试验,分别测试了GPS导航仿真子系统、多普勒测速仿真子系统和深度模拟子系统。试验结果表明,该仿真系统满足了仿真实时性和计算精度的要求,对于UUV研制具有重要的应用价值。

Abstract：

To satisfy the requirement of high accuracy simulation of complicated navigation and control system of unmanned underwater vehicle, a new plan of simulation system was proposed, which afforded the interface environment for SINS, Doppler velocity instrument, depth sensor and GPS receiver. The GPS satellite navigation signal simulation, the acoustic echo of Doppler velocity instrument and the sailing depth simulation were solved. The simulation experimentation combining hardware was processed, and the GPS simulation subsystem, the Doppler velocity simulation subsystem and the sailing depth simulation subsystem were all tested. The results show that the simulation system meets the real-time and accuracy requirements, and the system has important application value for UUV development.     

IMPROVED ROBUST H-INFINITY ESTIMATION FOR UNCERTAIN CONTINUOUS-TIME SYSTEMS

The design of full-order robust estimators is investigated for continuous-time polytopic uncertain systems. The main purpose is to obtain a stable linear estimator such that the estimation error system remains robustly stable with a prescribed H∞ attenuation level. Firstly, a simple alternative proof is given for an improved LMI representation of H∞ performance proposed recently. Based on the performance criterion which keeps the Lyapunov matrix out of the product of the system dynamic matrices, a sufficient condition for the existence of the robust estimator is provided in terms of linear matrix inequalities. It is shown that the proposed design strategy allows the use of parameterdependent Lyapunov functions and hence it is less conservative than the earlier results. A numerical example is employed to illustrate the feasibility and advantage of the proposed design.     

Global stabilizing controller design for linear time-varying systems and its application on BTT missiles

A parametric method for the gain-scheduled controller design of a linear time-varying system is given. According to the proposed scheduling method, the performance between adjacent characteristic points is preserved by the invariant eigenvalues and the gradually varying eigenvectors. A sufficient stability criterion is given by constructing a series of Lyapunov functions based on the selected discrete characteristic points. An important contribution is that it provides a simple and feasible approach for the design of gain-scheduled controllers for linear time-varying systems, which can guarantee both the global stability and the desired closed-loop performance of the resulted system. The method is applied to the design of a BTT missile autopilot and the simulation results show that the method is superior to the traditional one in sense of either global stability or system performance.     

基于有限元法的开关变换电路的近场特性分析

为进一步明确电力电子开关变换电路工作时的近场特性，尝试采用基于有限元方法的ANSYS软件以BUCK电路为例进街。了分析，首先采用场路锅合的方法得到与已有结果相符的电感线圈电流波形，在此基础上对采用不同布局的BUCK电路实体原型建立了有限元模型，并对其进行了3D电磁场分析，得到了清晰的电磁场分布及其变化规律。通过分析为电力电子电路的电磁兼容设计提供了依据和新的思路。     

高速背板互连的信号完整性仿真方法

提出了一种高速背板互连的信号完整性仿真方法。高速接插件的厂商只提供参数模型,借助矢量拟合方法可以推导出电路模型,再使用部分元等效电路法仿真走线得到等效电路模型。推导出联合仿真的方法,实现了高速背板互连的信号完整性仿真。通过等效电路的仿真结果和厂商提供的原始参数进行的比较,以及部分元等效电路法与商用软件仿真结果的比较验证了等效电路的正确性。最后对完整的板间互连通道进行了仿真,并将最终的仿真结果与商用软件的仿真结果进行了比较,证明了所提方法的正确性,给出了整个通道眼图仿真分析结果。     

基于MATLAB的电磁轴承开关功放建模与仿真研究

在分析电磁轴承开关功放的工作原理基础上,应用MATLAB/Simulink中的电力系统工具箱（PSB）建立了电磁轴承开关功放系统的仿真模型,并详细介绍了系统模型的内部结构和Simulink/PSB建模方法。电磁轴承开关功放系统的仿真与实验显示,仿真与实验结果吻合较好,验证了系统模型的正确性,从而为电磁轴承开关功放的特性分析提供了一种可行的研究方法。     

ADAPTIVE PRACTICAL OUTPUT MANEUVERING CONTROL FOR A CLASS OF NONLINEAR SYSTEMS

This paper deals with the adaptive practical output maneuvering control problems for a class of nonlinear systems with uncontrollable unstable linearization. The objective is to design a smooth adaptive maneuvering controller to solve the geometric and dynamic tasks with an arbitrary small steady tracking error. The method of adding a power integrator and the robust recursive design technique are employed to force the system output to track a desired path and make the tracking speed to follow a desired speed along the path. An example is considered and simulation results are given. The proposed design procedure can be illustrated by the use of this example.     

GNSS接收机射频前端电路相位噪声评估方法

相位噪声是影响全球卫星导航系统(global navigation satellite system, GNSS)接收机性能的一个重要因素,在高性能的接收机设计中,射频前端电路的相位噪声评测是不可忽略的。传统观测相位噪声的方法主要是利用频谱分析仪等专业仪器来实现,其无法观测GNSS接收机射频前端电路(包含模数(analog-digital，AD)转换器)的相位噪声。分析了接收机相位噪声和热噪声在信号复平面域的表现特征,提出了在信号复平面域评估GNSS接收机射频前端电路相位噪声的方法,并对该方法进行了仿真验证和实测验证。利用相位噪声对信号在复平面实部和虚部影响不同的特点,对采集到的信号数字中频数据进行相干积分处理,定量估算接收机射频系统的相位噪声。结果表明,该方法具有较高的评估准确度,可以用于测量与评估GNSS接收机射频前端电路(包含AD转换器)的设计质量,预测接收机性能。     

面向突发事件的电网韧性能力评价及构建方法

近年来,我国对电力系统面对突发事件时的性能表现提出了更为严格的要求,利用韧性的概念构建电网系统能够实现应急全周期内避免损失.文章利用应急管理理论分阶段刻画韧性的特征,在描述突发事件下电网韧性能力的同时提出了一种定量评价电网韧性的方法,它侧重于电网在突发事件发生后随着时间的推移维持稳定、抵抗中断、恢复性能的调整能力:利用给出的韧性评价指数结合电网特有的包括运行模式、组件物理强度和网络拓扑结构在内的电网特征,针对性地描述了能够增强电网韧性的措施.最后举例选取N-1准则措施利用PSCAD软件进行仿真模拟,利用韧性评价指数说明N-1措施能够增强电网韧性的同时,验证了韧性评价指数的合理性.电网实例引用IEEE14节点模型.     

闭环辨识条件下迭代激励信号设计方法

针对闭环系统辨识中激励信号的优化选择问题,提出一种迭代的优化激励信号设计方法.以优化控制的性能指标作为激励信号选择的目标函数,考虑闭环辨识的鲁棒性稳定性,以及激励信号、控制信号和输出信号的能量限定,求取激励信号的优化能量谱,并以迭代的方法逐步选择优化的激励信号和闭环辨识系统模型,从而得到满足闭环系统性能的系统模型和相应的激励信号.仿真验证结果表明,使用该方法得到的激励信号去激励闭环系统,进行模型辨识,能够有效提高辨识模型的准确性.     

基于射频收发器的高中频DBF系统设计

由于数字波束形成(digital beam forming,DBF)系统需要多个天线单元来形成波束,将极大增加系统的体积与功耗,无法很好地应用在无人机、导弹和微纳卫星平台中.针对上述问题,提出一种基于射频收发器AD9371的新型高中频(high intermediate frequency,high-IF)架构DBF系...     

基于小波分解的系统辨识最优实验设计

提出了一种基于小波分解的系统辨识最优输入信号的设计方法。将小波 的多分辨率分析理论应用于控制系统的最小二乘辨识中，并且与闭环系统的控制性能指标关联起来，从而得出一种最优辨识输入信号的设计方法。这种方法是与控制相关的一种辨识方法，能获得比普通的系统辨识方法更好的结果。仿真结果证明了这种方法的有效性。     

雷达伺服系统多目标优化控制设计及仿真研究

提出一类新型非线性控制器和多目标优化控制系统大相角裕量设计法。应用这些结果对线性优化系统进行优化,可以获得性能指标比原系统好得多的多目标优化控制系统。给出用大相角裕量多目标优化设计法来设计雷达伺服系统的实例,计算机仿真校验其性能指标的结果表明,多目标优化系统的性能指标确比线性优化系统好。设计方法简单、通用、适用于工程设计。