泛探雷达时-空级联目标检测与DOA估计算法

针对"泛探"雷达,提出了一种时-空级联目标检测和DOA估计算法,该方法首先利用基于DFT的数字波束形成技术完成阵元空间到波束空间的转换,然后对协方差矩阵的迹做门限检测,最后采用多级维纳滤波的子空间分解法进行到达角估计。仿真结果表明,本文提出方法对比长时间相参积累和单脉冲比幅测向方法具有较好的时域检测和测向能力。     

一种确定检测时间的方法

在许多作为侦察用的无源传感器只报出其检测结果时,利用此传感器一系列检测报告确定被检测目标何时进入及何时离开此传感器检测区域,成为解决决策级信尽融合问题的关键。本文讨论了一种利用序贯分析方法计算检测时间的近似方法。     

基于改进协方差控制的传感器管理算法

针对传统的基于协方差控制的传感器管理算法使用全遍历方法所造成的计算量大,以及传感器切换频繁的问题,提出了一种基于改进协方差控制的传感器管理算法。该算法在每一时刻首先判断前一时刻所用传感器组是否能够满足目标跟踪需求,以滤波协方差与期望协方差的偏差作为参考,结合量纲变换和特征值求取,为协方差偏差矩阵经过量纲变换后得到的量纲一致阵的所有特征值设定一个精度阈值,然后判断滤波协方差是否满足期望,从而决定是否维持当前选择的传感器组。在目标作匀速、匀加速、协同转弯等多种场景下进行了算法性能测试分析,仿真结果表明,该算法不仅在大部分场景下满足目标跟踪精度,而且能够提高传感器管理算法的实时性,同时降低传感器的切换频率。     

The prediction formula and a risk-based sensor scheduling method in target detection with guiding information

Sensor scheduling is used to improve the sensing performance in the estimation of targets' states. However, few papers are on the sensor scheduling for target detection with guiding information. This letter can remedy this deficiency. A risk-based target detection method with guiding information is provided firstly, based on which, the sensor scheduling approach is aiming at reducing the risk and uncertainty in target detection, namely risk-based sensor scheduling method. What should be stressed is that the Prediction Formula in sensor scheduling is proposed. Lastly, some examples are conducted to stress the effectiveness of this proposed method.     

基于方位角和多普勒的机动目标无源定位跟踪可观测条件

可观测性分析是无源定位与跟踪系统的前提和基础,只有满足可观测条件才能对系统进行正确求解。应用线性系统理论,以目标方位角和多普勒频率为观测量,对匀加速和匀转弯这两类最常见的机动目标进行了可观测分析,为进一步研究机动目标的无源定位与跟踪提供了理论前提。最后给出了仿真实例,验证了理论分析的正确性。     

基于到达时差法的目标定位系统

运用声被动定位理论探索空中目标的定位问题。建立了一种平面波声被动定位模型,利用简易被动声传感器阵列,分析并设计了定位系统的总体结构。提出了一种简易的计算到达时差电路设计方案,此电路利于目标的实时定位。在利用这种系统定位远距离目标时,可消除有效声速的影响。最后给出了几组实验结果,证明了此系统的可行性,但对近距离目标的定位结果较差,模型需进一步研究。     

多传感器信息的表决融合

介绍了一种多传感器信息综合方法─—表决融合。这种方法的前提是各传感器自身的处理器完成对各自的原始探测信息的处理,处理结果以合乎要求的形式输入融合中心,以便融合中心能以表决的形式进行融合处理。由于融合中心没有复杂的信息处理任务,因此,十分便于工程实现。作为例子,本文给出的是一个３传感器目标检测系统,每个传感器都定义了置信级别。融合中心的工作就是利用各传感器的检测结果和相应的置信水平来进行融合处理的。最后,还对文献１进行了探讨。     

一种无线传感器网络中的Sybil攻击检测方案

Sybil攻击破坏无线传感器网络中的数据融合、公平资源分配等机制，因此对Sybil攻击的防范与检测具有很重要的意义。将一种基于到达时间差（TDOA）的三维定位引入到Sybil攻击的检测中，算法可以检测存在的Sybil攻击并对Sybil节点进行定位。通过性能分析证明该算法具有开销小、有效性高的特点。     

基于加权动态规划和航迹关联的小目标检测技术

低信噪比下运动小目标的检测一直是成像目标检测中的一个热点问题。提出了一种新的小目标检测算法,采用方向加权的动态规划算法和二值航迹关联,克服了低信噪比下目标机动和传感器的不稳定对小目标检测的影响,实现了对深空背景下运动方式任意、速度最大达1像素/帧的弱小运动目标的有效检测。     

红外警戒系统点目标检测距离理论分析

给出了红外警戒系统点目标探测距离的计算模型与公式,分析了影响点目标探测距离的参数间关系,并得出有关目标提取算法及传感器参数选择的几点重要结论.     

Due‐window assignment with unit processing‐time jobs

In due‐window assignment problems, jobs completed within a designated time interval are regarded as being on time, whereas early and tardy jobs are penalized. The objective is to determine the location and size of the due‐window, as well as the job schedule. We address a common due‐window assignment problem on parallel identical machines with unit processing time jobs. We show that the number of candidate values for the optimal due‐window starting time and for the optimal due‐window completion time are bounded by 2. We also prove that the starting time of the first job on each of the machines is either 0 or 1, thus introducing a fairly simple, constant‐time solution for the problem. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004     

双站测向与测时差组合定位精度分析

针对无源雷达测向与测时差组合定位问题,提出一种利用前者量测结果为后者构建假量测点和协方差的新方法,并采用凸组合法对测向与假量测结果进行融合,得出综合定位精度的分布。仿真结果表明,该方法能够有效地利用两种完全不同的量测数据,提高目标的定位精度,同时给出的GDOP理论值可以真实反映组合量测的性能,具有一定的应用价值。     

多重优化的分布式无线覆盖探测算法

为满足无线通信网络信号覆盖有效性的实时实地可重复探测的需求,提出一种基于传感器网络的分布式无线覆盖探测算法。通过随机部署于目标区域内的无线传感器节点对无线通信网接收信号强度进行感知和预处理;利用变异函数构造新的BP神经网络目标函数,通过改进粒子群算法优化其初始权值和阈值;利用训练好的网络模型对存在探测盲区的目标区域进行插值估计,并联合传感器节点采集到的数据生成无线通信网络等信号强度线。仿真结果表明,所提算法比其他经典算法具有更高的精度,可有效探测目标区域无线通信网络的信号覆盖情况。     

Many‐server loss models with non‐poisson time‐varying arrivals

This article proposes an approximation for the blocking probability in a many‐server loss model with a non‐Poisson time‐varying arrival process and flexible staffing (number of servers) and shows that it can be used to set staffing levels to stabilize the time‐varying blocking probability at a target level. Because the blocking probabilities necessarily change dramatically after each staffing change, we randomize the time of each staffing change about the planned time. We apply simulation to show that (i) the blocking probabilities cannot be stabilized without some form of randomization, (ii) the new staffing algorithm with randomiation can stabilize blocking probabilities at target levels and (iii) the required staffing can be quite different when the Poisson assumption is dropped. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 177–202, 2017     

Single-lane bridge serving two-lane traffic

This paper presents a mathematical model of a single-lane bridge serving two-way traffic in alternating directions (with an FIFO rule observed within each directional queue). While the bridge serves cars moving in one direction, cars approaching from the opposite direction wait in a queue at its foot. When cars in the current direction finish crossing the bridge, it begins serving cars from the other direction, if any are present. A newly-arrived car finding an empty bridge mounts it immediately. Several cars moving in the same direction may occupy the bridge simultaneously. The crossing speed is assumed to be constant, and the arrival processes in both directions are assumed to be independent, homogeneous Poisson processes. A generalization of the alternating-priority models [1, 2] is developed to arrive at the Laplace-Stieltjes transform and the expected value of the flow time (the time interval between the moments of arrival at the bridge and departure from it) for steady state conditions. The results are discussed and some examples are presented graphically.     

临近空间传感器分布式组网研究

研究了临近空间分布式传感器网联合发现目标概率,探讨了区域警戒传感器网中部署传感器数目与该网总发现概率等的关系,提出了3种特殊的分布式网络传感器区域的布防模式,并建立了定量评价传感器网性能指标的数学模型。模型的建立为定量评估传感器组网系统效能奠定了理论基础,也为分布式传感器网络系统的部署优化、传感器的选配等提供决策依据。     

箔条云干扰下的单目标恒虚警率检测研究

箔条云在扩散过程中随着时间变化会稀释和扩大,其回波特性会发生改变,被检测目标与箔条的相互位置关系也会影响雷达恒虚警检测。针对作战对抗过程中箔条干扰易造成雷达接收机阻塞干扰目标检测,检测概率迅速降低且易丢失目标贻误战机,通过详细分析箔条的扩散过程及信号频谱特性及其箔条云和目标的两种位置关系,利用恒虚警处理算法在噪声基底为10 dB和20 dB情况下对目标进行恒定虚警率检测研究。研究结果对改善飞机检测性能和抗虚警能力以及提高战场生存率具有积极作用。     

Optimal search using two nonconcurrent sensors

Search for a stationary target is considered for a situation in which two sensors are available, but cannot be used simultaneously. The cost (in time) of switching from one sensor to the other is ignored, and each sensor is assumed to have perfect discrimination. For a specified class of searches an optimal allocation of search effort is obtained. In the case of a circular normal prior target location distribution, an example is presented in which one sensor is assumed to have a fixed sweep width and the other a stochastic sweep width. An optimal plan is found for this example. This plan produces an allocation of search effort which is expended in a disk by one sensor and in a bounding annulus by the other.     

噪声目标转向机动自动检测

根据观测器--目标保持匀速直线运动时目标方位随时间线性变化的一种可量测函数,研究了一种检测目标转向机动的新方法.由于该方法将目标方位随时间变化的非线性关系转换到另一空间的线性关系,这使得检测更加有效、直观,并且能够克服直接采用方位序列检测目标转向机动在特殊情况下失效的限制.最后计算机仿真计算及实测数据验证结果表明,该方法能快速、准确地检测目标的转向机动.     

巨磁阻传感器在齿轮精细检测中的应用

提出一种利用巨磁阻传感器进行齿轮精细检测的方法,介绍该方法的检测原理和系统组成,从可分辨最小磁场、时间响应和温度特性3个方面分析应用巨磁阻传感器的可行性和有效性,并通过实例测量实现对齿轮的磨损、点蚀等故障的有效检测与诊断.