目标起伏特性对雷达威力性能的影响分析

介绍了典型雷达目标RCS起伏模型,阐述了起伏目标在实际中的应用,建立了目标损耗和雷达作用距离之间的关系,为不同目标的等效替代推算提供了理论依据.验证了雷达目标满足卡平方分布时发现概率和起伏因子之间的关系.并针对不同类型的起伏目标,建立了雷达探测距离和发现概率之间的关系,为雷达的威力检测和飞行目标的航线设计提供依据.     

Adaptive sliding mode control of modular self-reconfigurable spacecraft with time-delay estimation

The reconstruction control of modular self-reconfigurable spacecraft (MSRS) is addressed using an adaptive sliding mode control (ASMC) scheme based on time-delay estimation (TDE) technology. In contrast to the ground, the base of the MSRS is floating when assembled in orbit, resulting in a strong dynamic coupling effect. A TED-based ASMC technique with exponential reaching law is designed to achieve high-precision coordinated control between the spacecraft base and the robotic arm. TDE technology is used by the controller to compensate for coupling terms and uncertainties, while ASMC can augment and improve TDE’s robustness. To suppress TDE errors and eliminate chattering, a new adaptive law is created to modify gain parameters online, ensuring quick dynamic response and high tracking accuracy. The Lyapunov approach shows that the tracking errors are uniformly ultimately bounded (UUB). Finally, the on-orbit assembly process of MSRS is simulated to validate the efficacy of the proposed control scheme. The simulation results show that the proposed control method can accurately complete the target module’s on-orbit assembly, with minimal perturbations to the spacecraft’s attitude. Meanwhile, it has a high level of robustness and can effectively eliminate chattering.     

One-bit splitting deceptive jamming against SAR

One-bit quantization is a promising technique due to its performance retention and complexity reduction in a deceptive jammer against synthetic aperture radar (SAR). In this paper, the 1-bit quantization technology is utilized to agilely generate split false targets in the SAR imagery once the radar signal is intercepted, which reduces the complexity of the jammer significantly with guaranteed focusing quality. A single-frequency threshold is used to decompose harmonics incurred by the 1-bit quantization, and its parameters are adjusted through different pulse repetition intervals to provide steerable modulations. In this way, the SAR signal is split into coupled false scatterers during the 1-bit interception. By further deploying amplitude, time-delay, and Doppler frequency modulations on the 1-bit intercepted signal, the split false targets are created. The proposed approach is compared with different deceptive jamming methods to show its validity in effectiveness and cost, and numerical experiments are also presented for verification.     

基于语言评价与模糊数的群体意见共识方法

针对具有自然语言评价信息的群决策问题,给出了一种基于语言评价信息与梯形模糊数的群体意见共识方法.该方法先通过无量纲化处理、语言评价信息转换为梯形模糊数、对梯形模糊数进行集结等步骤,形成群体对方案的综合评价值(梯形模糊数);然后对群体意见进行共识分析和评价;最后对共识结果进行方案排序.通过对实例进行分析,表明该方法能得到切合实际的决策效果.     

基于GA的模糊PID控制在质量矩导弹系统上的应用

针对三轴稳定的质量矩导弹姿态控制系统,提出了一种基于遗传算法进行参数寻优的模糊PID控制方法。在建立姿控系统数学模型的基础上,首先设计了姿态控制的优先级函数,然后根据实际的姿态控制系统,设计了遗传算法的性能指标函数和具体的优化策略,最后给出了模糊PID控制器的设计思路。仿真结果说明了该方法的有效性。     

高频地波雷达目标高度估计的AR模型方法

高度估计对于高频地波雷获取三维信息、提高预警能力很有意义。然而目标RCS的随机起伏对高度估计产生严重影响,通过对RCS随机起伏的AR模型建模和模型参数的自适应估计,提出了在RCS变化的条件下高度估计的扩展卡尔曼滤波算法。通过Monte Carlo仿真和外场试验数据的处理,验证了该方法对抑制RCS随机起伏、提高高度估计精度的有效性。     

基于频率补偿的时延估计方法

由于2个测量站的通道幅相不一致而导致送给时延估计器的两路信号的频率有差异,继而影响时延估计和系统定位精度。首先理论推导了频率差异是如何影响广义相关时延估计的,接着应用频域相关函数对频率差异做准确估计和补偿,最后给出了频差补偿后的时延估计方法。以4种常用通信信号为例,仿真验证了不同信噪比下所提出方法的正确性和有效性。     

应急指挥决策方案的模糊综合评价研究

针对灾害现场应急指挥决策方案优选问题,提出了方案优选评价的可行性、时效性和安全性指标,应用模糊数学的相关理论构建了模糊综合评价的数学模型,采取专家调查打分法解决了方案评价影响因素的权重值及其评价等级的隶属度的确定问题,并采取加权平均算法对权重集A和影响因素评判隶属度矩阵R进行运算,得到的结果不仅反映了所有因素权值的影响,而且保留了单因素评判的全部信息,能够体现"模糊综合评价"的实质。     

混合气体识别的响应等效性与瞬态信号正交分解模型

针对目前混合气体识别大多采用传感器稳态响应信号、基于线性混合假设或大量样本学习,而瞬态响应信号特征分析主要应用非正交分解的问题,提出一种基于响应等效性与瞬态信号正交分解的混合气体识别模型。分析金属氧化物半导体传感器对混合气体的响应特性,建立基于气体响应成分等效性假设的气体非线性混合模型,在此基础上,提出并应用一种新的正交基函数——扩展类Legendre正交基,对气体传感器瞬态响应信号进行分解;通过对正交分解系数与气体浓度的回归分析,验证二者之间的指数型关联关系,并以正交分解系数为特征参数,利用气体非线性等效混合模型对混合气体分解与辨识。实验结果表明,尽管这种混合气体识别模型仅用单一气体检测的先验知识,对混合气体的识别误差仍可达到15%以内。     

装甲装备作战效能评估的模糊Petri网模型研究

利用模糊Petri网清晰、简单的知识表示能力和模糊推理能力,将其应用于装甲装备作战效能评估中。基于"能力需求分析"方法建立了装甲装备的分层效能评估指标体系,并对其优化和赋权方法做了简要介绍;介绍了模糊Petri网的定义和基于BP算法的学习能力;在此基础上以装甲装备战场感知能力二级指标为例介绍了基于模糊Petri网模型的评估方法,并对评估结果进行了分析。