基于UT变换的自适应扩维IMM电扫描跟踪算法

针对机动目标跟踪问题,采用扩维的匀速和转弯(ACV-2ACT)模型组成模型集,结合电扫描雷达波束灵活的特点,利用自适应调度算法,设计了一种基于UT变换的自适应扩维IMM算法.通过无味滤波器估计转弯率和状态,使模型集具有自调整能力.与EKF-AIMM算法进行仿真比较,结果表明在相同情况下,本算法有较好的稳定性,能更加有效节约雷达资源.     

IMM/MHT fusing feature information in visual tracking

In multi-target tracking, Multiple Hypothesis Tracking (MHT) can effectively solve the data association problem. However, traditional MHT can not make full use of motion information. In this work, we combine MHT with Interactive Multiple Model (IMM) estimator and feature fusion. New algorithm greatly improves the tracking performance due to the fact that IMM estimator provides better estimation and feature information enhances the accuracy of data association. The new algorithm is tested by tracking tropical fish in fish container. Experimental result shows that this algorithm can significantly reduce tracking lost rate and restrain the noises with higher computational effectiveness when compares with traditional MHT.     

基于修正无偏转换测量的交互式多模型算法

雷达系统中的目标跟踪技术不仅需要从噪声中将能够直接测量得到的信号提取出来,估计出不能直接测量的诸如目标加速度等信息;而且还要处理从球坐标系到笛卡尔直角坐标系下量测的非线性转换。针对此问题,本文提出了集交互式多模型和修正的无偏转换测量两者优点的IMM-MUCMKF跟踪算法。理论分析和仿真结果表明,本算法的跟踪性能要优于集交互式多模型和不敏卡尔曼的IMM-UKF算法。     

角闪烁背景下基于IMM算法的末制导雷达目标跟踪

为了抑制末制导雷达目标跟踪过程中的角闪烁噪声,对闪烁噪声的统计特性进行了分析,建立了符合其分布的统计模型及系统的状态空间模型,用交互多模型算法解决了角闪烁背景下的目标跟踪问题;并根据该问题的特点,对IMM算法进行了简化.仿真结果表明,用交互多模型方法抑制角闪烁噪声是非常有效的,基于转换卡尔曼滤波的IMM算法比基于扩展卡尔曼滤波的IMM算法具有更高的跟踪精度;简化的IMM算法虽然在跟踪精度上不如基本的IMM.但仍然达到了很好的滤波效果,而且大大降低了计算的复杂程度,是一种更符合工程实际的抑制角闪烁噪声的方法.     

具有径向速度量测雷达的自适应波形选择问题研究

针对二维机动目标跟踪的波形选择问题,将传统正交自适应波形选择法进行扩展。该波形选择方法以IMM-EKF作为基础跟踪算法,将IMM-EKF输出的预测协方差对应的椭球投影到r-r觶平面上,选择量测误差椭圆与投影椭圆正交的发射波形。仿真结果表明,该算法可以有效改善目标跟踪精度,并讨论了参数选择对正交法改善跟踪系统精度的影响。     

一种IMM和JPDA混合型多目标跟踪算法研究

本文研究基于IMMJPDA算法的多机动目标跟踪,并对IMMJPDA算法中聚矩阵的构成进行了改进.当目标采用不同模型时,将产生多个相互独立的聚矩阵和可行矩阵,同时得到相应的可行矩阵的条件概率.最后利用模型概率对上述条件概率进行加权求和得到关联概率.改进后的IMMJPDA算法在RMSE超调性能上有了一定的提高.     

A tracker-aware detector threshold optimization formulation for tracking maneuvering targets in clutter

In this paper, we consider a tracker-aware radar detector threshold optimization formulation for tracking maneuvering targets in clutter. The formulation results in an online method with improved transient performance. In our earlier works, the problem was considered in the context of the probabilistic data association filter (PDAF) for non-maneuvering targets. In the present study, we extend the ideas in the PDAF formulation to the multiple model (MM) filtering structures which use PDAFs as modules. Although our results are general for the MM filters, our simulation experiments apply the proposed solution in particular for the interacting multiple model PDAF (IMM-PDAF) case. It is demonstrated that the suggested formulation and the resulting optimization method exhibits notable improvement in transient performance in the form of track loss immunity. We believe the method is promising as a detector-tracker jointly-optimal filter for the IMM-PDAF structure for tracking maneuvering targets in clutter.     

飞机姿态角辅助的交互式多模型跟踪算法

为借助飞机姿态角提高跟踪性能,在一种改进的IMM算法基础上,一方面,对飞机处于各运动模型时姿态角的变化规律进行分析,利用姿态角求解角度变化率来实时更新模型集;另一方面,通过在姿态角滤波过程中加入机动检测和极性判别,提升了离散点过程滤波器的输入量测值的精度.之后,提出了一种基于飞机姿态角辅助的交互式多模型跟踪算法.仿真验...     

一种基于UKF交互多模型算法

交互多模型采用模型软切换方式有效地解决了目标运动模式多样化的问题,是目前最具实用性的多模型机动目标跟踪算法。自从1988年提出该算法后,迅速在雷达机动目标跟踪与雷达组网技术中得到了广泛的应用。结合交互多模型算法和目前发展较为成熟的非线性估计算法———无味滤波算法,以高机动反舰导弹目标跟踪为应用背景,以基于匀速运动、匀加速运动、匀速转弯和“当前”统计模型这四种跟踪模型组成的模型集为基础,对交互多模型算法进行了仿真研究,证实了该算法的有效性。     

Radiation degradation characteristics of component subcells in inverted metamorphic triple‐junction solar cells irradiated with electrons and protons

The radiation response of In_0.5Ga_0.5P, GaAs, In_0.2Ga_0.8As, and In_0.3Ga_0.7As single‐junction solar cells, whose materials are also used as component subcells of inverted metamorphic triple‐junction (IMM3J) solar cells, was investigated. All four types of cells were prepared using a simple device layout and irradiated with high‐energy electrons and protons. The essential solar cell characteristics, namely, light‐illuminated current–voltage (LIV), dark current–voltage (DIV), external quantum efficiency (EQE), and two‐dimensional photoluminescence (2D‐PL) imaging were obtained before and after irradiation, and the corresponding changes due to the irradiations were compared and analyzed. The degradation of the cell output parameters by electrons and protons were plotted as a function of the displacement damage dose. It was found that the radiation resistance of the two InGaAs cells is approximately equivalent to that of the InGaP and GaAs cells from the materials standpoint, which is a result of different initial material qualities. However, the InGaAs cells show relatively low radiation resistance to electrons especially for the short‐circuit current (I sc). By comparing the degradation of I sc and EQE, data, It was confirmed that the greater decrease of minority‐carrier diffusion length in InGaAs compared with InGaP and GaAs causes severe degradation in the photo‐generation current of the InGaAs bottom subcells in IMM3J structures. Additionally, it was found that the InGaP and two InGaAs cells exhibited equivalent radiation resistance of V oc, but radiation response mechanisms of V oc are thought to be different. Further analytical studies are necessary to interpret the observed radiation response of the cells. © 2016 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd.