基于动态加权的分布式多传感器航迹融合算法

针对目前分布式航迹融合算法中鲁棒性和实时性问题,基于充分利用多传感器测量数据中互补和冗余信息的思想,通过局部航迹估计间模糊支持度函数的建立和支持度矩阵的求解,动态地实现各局部航迹估计在融合中心权重的合理分配,进而提出了一种基于动态加权的分布式多传感器航迹融合算法。最后,通过蒙特卡罗仿真验证了该算法的有效性。     

A-SMGCS的多场面监视雷达多目标航迹相关

航迹融合由航迹相关和航迹合成组成,航迹相关是航迹融合的前提;针对先进场面运动引导控制系统(A-SGMCS)中场面监视雷达对目标的跟踪,文中研究了多场面监视雷达的多目标航迹相关问题;首先,建立分布式多场面监视雷达多目标航迹融合的总体框架,利用GPS授时和外推内插的方式进行场面监视雷达的同步,利用坐标平移实现空间对准;然后,介绍基于层次划分思想的聚类算法,再利用此方法进行多场面监视雷达多目标跟踪的航迹相关研究;最后,进行了仿真验证;仿真结果表明,文中所采用的方法对目标数确定和不确定的航迹都能够进行正确相关,有效地解决了场面监视雷达的航迹相关问题。     

噪声方差未知情况下多传感器航迹融合

在多传感器信息融合中,已有的航迹融合算法都是在噪声方差已知情况下基于最优的卡尔曼滤波算法的,而实际应用中噪声方差往往是未知的.针对上述问题,基于扩展记忆因子递推最小平方(EFRLS)估计的滤波方程,研究了噪声方差未知情况下集中式、分布式、混合式多传感器航迹融合方法.并对三种航迹融合算法的跟踪性能和卡尔曼滤波融合算法的性能进行了仿真比较.由于多级式多传感器的航迹融合方法可由本文的方法直接推广,所以只需研究两级的情况就可.     

基于改进加权航迹关联的异步融合算法与仿真

在分布式多传感器信息融合系统中,来自各传感器的局部航迹往往是不同步的。针对分布式多传感器异步航迹关联与融合问题,文中提出一种基于改进加权航迹关联的异步航迹顺序融合算法。把多传感器异步航迹外推校准到同一时刻,实现异步航迹的同步化,再用改进的加权航迹关联算法进行航迹关联,并利用顺序融合算法对已关联航迹进行融合。仿真结果表明了该算法的有效性。     

一种新的异类传感器信息融合算法

针对典型的雷达和红外异类传感器信息融合系统,提出了一种新的雷达和红外信息融合算法。对雷达和红外传感数据进行了预处理,分别滤波得到各自的局部航迹,基于线性最小均方误差准则（Linear Minimum Mean Square Error,LMMSE）对局部航迹进行融合以得到最终航迹。仿真结果表明：该算法可以对雷达和红外传感器进行有效融合并大幅提高航迹跟踪精度。     

带反馈信息的多传感器航迹融合算法

基于分布式多传感器航迹融合系统,采用序贯处理的方法,研究了相关条件下带反馈信息的多传感器航迹融合问题.以估计误差方差阵迹最小准则导出了相应的融合算法,并进行了仿真分析.仿真结果表明带反馈信息的多传感器航迹融合算法的可行性和有效性,同时也表明带反馈的融合算法比不带反馈的融合算法具有更高的跟踪精度.     

多传感器噪声方差未知情况下的异步航迹融合

针对分布式多传感器数据融合系统,提出了一种多传感器异步航迹融合算法。现有的多传感器信息融合算法大都基于Kalman滤波器,要求噪声方差已知,并且假定各传感器同步采样,不考虑通信延迟。本文在分布式处理的模式下,基于各传感器在扩展记忆因子递推最小平方(EFRLS)估计形成本地航迹的基础上,提出了一种融合误差均方差矩阵的迹最小意义下的异步目标航迹融合算法。仿真实验结果表明,这种融合算法是有效的,算法接近集中式融合算法的精度。     

无人飞行器航迹方案的VIKOR择优评价

针对无人飞行器智能航迹规划算法导致的多航迹选择问题,构建基于多准则妥协解排序法(VIKOR)的航迹路线择优评价体系.为快速获得各威胁源的综合威胁信息,采用路线分割和极限的思想,建立综合威胁计算模型,并给出模型参数变化范围计算方法.以变异系数法确定指标权重,采用可最大化群体利益且弱化个体遗憾的VIKOR算法融合威胁信息,给出基于VIKOR算法的航迹方案择优评价方法和步骤.该评价方法可获得具有优先级别的妥协最优航迹方案,使评价结果更容易被决策者接受.实际航迹路线择优问题验证了所提出方法的有效性.     

基于新型AFCM的多传感器目标跟踪航迹融合

多目标跟踪是多传感器系统信息融合中的核心技术之一.采用新型的AFCM模糊算法实现对多目标交叉状态下航迹数据关联.该算法定义了一种新的度量空间中的距离,通过新的距离定义有效抑制含有噪声点的样本及目标航迹交叉在迭代中对数据关联聚类中心点的大幅偏差.同时应用改进带加权的航迹融合算法对红外和毫米波雷达传感器测量的航迹数据进行融合.仿真试验证明,新的算法在综合多传感器探测优势的基础上,对航迹的融合结果优于SF算法.新的数据关联算法和改进的加权航迹融合算法为多源信息融合提供了一种可靠有效的多目标跟踪技术.     

基于反馈结构的多传感器自适应航迹融合算法

在分布式多传感器信息融合系统中,自适应融合算法通过预先设定两个距离测度。然后将它们与逻辑判决树中的阈值进行比较来选择不同的融合算法,达到适应系统特性的不断变化,平衡精度与计算量之间矛盾的目的;反馈结构可用来提高局部节点的跟踪性能,进而提高全局航迹的融合精度．综合上述两种方法,提出一种新的基于反馈结构的多传感器自适应航迹融合算法,并在传感器异步的情况下讨论了其具体的计算过程．仿真结果表明该算法以较小的计算量达到了近似加权协方差算法（WCF）的融合精度．     

基于伪测量的分布式最优单步延迟航迹融合估计

融合中心如何处理无序局部数据,对分布式多传感器系统的运行品质至关重要．本文将系统中的局部估计转化为伪测量,将分布式融合估计转化为二级集中式融合估计．将所得的伪测量兼分布式融合估计算法与单步延迟的无序测量数据（out-of-sequencemeasurements,OOSM）最优滤波-A1算法进行组合,得出了分布式多传感器系统的最优单步延迟无序航迹（out-of-sequence tacks,OOST）估计算法,适用于航迹无序局部数据融合估计．该算法具有最优估计性能．     

Identification of nonlinear systems with outliers using wavelet neural networks based on annealing dynamical learning algorithm

This paper presents an annealing dynamical learning algorithm (ADLA) to train wavelet neural networks (WNNs) for identifying nonlinear systems with outliers. In ADLA–WNNs, wavelet-based support vector regression (WSVR) is adopted to determine the initial translation and dilation of a wavelet kernel and the weights of WNNs due to the similarity between WSVR and WNNs. After initialization, ADLA with nonlinear time-varying learning rates is applied to train the WNNs. In the ADLA, the determination of the learning rates would be a key work for the trade-off between stability and speed of convergence. A computationally efficient optimization method, particle swarm optimization (PSO), is adopted to find the optimal learning rates to overcome the stagnation in the training procedure of WNNs. Due to the advantages of WSVR and ADLA (WSVR–ADLA), the WSVR-based ADLA–WNNs (WSVR–ADLA–WNNs) can robust against outliers and achieve the promising efficiency of system identifications. Three examples are simulated to confirm the performance of the proposed algorithm. From the simulated results, the feasibility and superiority of the proposed WSVR–ADLA–WNNs for identifying nonlinear systems with artificial outliers are verified.     

Multi-Source Adaptive Selection and Fusion for Pedestrian Dead Reckoning

Accurate multi-source fusion is based on the reliability, quantity, and fusion mode of the sources. The problem of selecting the optimal set for participating in the fusion process is nondeterministic-polynomial-time-hard and is neither sub-modular nor super-modular. Furthermore, in the case of the Kalman filter (KF) fusion algorithm, accurate statistical characteristics of noise are difficult to obtain, and this leads to an unsatisfactory fusion result. To settle the referred cases, a distributed and adaptive weighted fusion algorithm based on KF has been proposed in this paper. In this method, on the basis of the pseudo prior probability of the estimated state of each source, the reliability of the sources is evaluated and the optimal set is selected on a certain threshold. Experiments were performed on multi-source pedestrian dead reckoning for verifying the proposed algorithm. The results obtained from these experiments indicate that the optimal set can be selected accurately with minimal computation, and the fusion error is reduced by 16.6% as compared to the corresponding value resulting from the algorithm without improvements. The proposed adaptive source reliability and fusion weight evaluation is effective against the varied-noise multi-source fusion system, and the fusion error caused by inaccurate statistical characteristics of the noise is reduced by the adaptive weight evaluation. The proposed algorithm exhibits good robustness, adaptability, and value on applications.      

雷达与ACARS数据融合研究

为了更好地利用雷达与ACARS进行空中目标监控,研究了雷达与ACARS的数据融合问题,提出了一种数据融合算法。对雷达与ACARS数据进行坐标变换和时空配准;对二者进行航迹关联,包括空间粗关联、逻辑航迹关联和多义性处理;对关联航迹进行融合。仿真结果表明,该算法可以提高空中目标监控的数据率,识别出雷达中的部分商用和通用航空飞机,得到目标更加详细和准确的信息。     

Optimizing wavelet neural networks using modified cuckoo search for multi-step ahead chaotic time series prediction

Determining the optimal number of hidden nodes and their proper initial locations are essentially crucial before the wavelet neural networks (WNNs) start their learning process. In this paper, a novel strategy known as the modified cuckoo search algorithm (MCSA), is proposed for WNNs initialization in order to improve its generalization performance. The MCSA begins with an initial population of cuckoo eggs, which represent the translation vectors of the wavelet hidden nodes, and subsequently refines their locations by imitating the breeding mechanism of cuckoos. The resulting solutions from the MCSA are then used as the initial translation vectors for the WNNs. The feasibility of the proposed method is evaluated by forecasting a benchmark chaotic time series, and its superior prediction accuracy compared with that of conventional WNNs demonstrates its potential benefit.     

Optimization of wavelet neural networks with the firefly algorithm for approximation problems

The effectiveness of swarm intelligence has been proven to be at the heart of various optimization problems. In this study, a recently developed nature-inspired algorithm, specifically the firefly algorithm (FA), is integrated in the learning strategy of wavelet neural networks (WNNs). The FA, which systematically optimizes the initial location of the translation parameters for WNNs, has reduced the number of hidden nodes while simultaneously improved the generalization capability of WNNs significantly. The applicability of the proposed model was demonstrated through empirical simulations for function approximation study, with both synthetic and real-world data. Performance assessment demonstrated its enhancement over the K-means clustering and random initialization approaches, as well as to the other neural network models reported in the literature, whereby a noteworthy decrease in the approximation error was observed.

     

Adaptive annealing learning algorithm-based robust wavelet neural networks for function approximation with outliers

In this study, a robust wavelet neural network (WNN) is proposed to approximate functions with outliers. In the proposed methodology, firstly, support vector machine with wavelet kernel function (WSVM) is adopted to determine the initial translation and dilation of a wavelet kernel and the weights of WNNs. Then, an adaptive annealing learning algorithm (AALA) is adopted to accommodate the translations, the dilations, and the weights of the WNNs. In the learning procedure, the AALA is proposed to overcome the problems of initialization and the cut-off points in the robust learning algorithm. Hence, when an initial structure of the WNNs is determined by a support vector regression (SVR) approach, the WNNs with AALA (AALA-WNNs) have fast convergence speed and can robust against outliers. Two examples are simulated to verify the feasibility and efficiency of the proposed algorithm.     

多传感器异步航迹融合算法与仿真

针对分布式多传感器数据融合系统,提出了一种多传感器异步航迹融合算法。由于不同传感器的采样时间各不相同,融合算法首先利用最小二乘法将局部航迹统一到融合中心的融合时间点,然后利用多传感器自适应航迹融合算法,将局部航迹进行融合,得到系统航迹。仿真结果表明该算法能够较好的解决异步航迹的融合问题,以较小的计算量达到了接近加权协方差(WCF)算法的融合精度。     

无线传感器网络簇内自适应融合算法研究*

无线传感器网络中采集的数据存在着较大的冗余与误差,且影响数据的可靠性。针对这个问题,分析了簇内数据误差成因,提出了一种改进后的自适应数据融合算法。该算法从节点测量数据自身着手,通过迭代得到各个节点测量数据的无偏估计值,以各个节点与估计值的欧氏距离作为各节点可信度的描述。实验证明,该融合算法提高了数据的精度和可信度。同时,通过与分批估计融合方法和传统的自适应加权融合方法的比较分析,表明该方法融合效果更好。