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1.
研究了多传感器多目标的数据关联问题,提出了杂波环境下多传感器多目标跟踪的极大似然关联算法.算法中考虑了传感器对目标的漏检情况,在各个观测站传感器的观测数据不完备的情况下,建立了传感器测量与目标的可行关联分配模型,并综合采用了假点的后验概率比模型,提高了多传感器对同一目标测量的互补性和对弱信号目标的跟踪精度.理论分析和仿真实验结果表明,所提出的算法可实现杂波环境下对弱目标的持续跟踪,并且在确保航迹关联性能和较好跟踪效果的基础上,降低了算法的运算量.  相似文献   

2.
基于内嵌光纤Bragg光栅传感器的光纤光栅.玻璃纤维增强塑料复合筋(GFRP—OFBG筋),研究了GFRP-OFBG筋自身的应变和温度传感特性,研究结果表明,GFRP—OFBG智能筋具有优异的线性传感性能,筋中光栅测量的应变极限达12000με以上,波长变化达14nm;对于用GFRP-OFBG筋替换普通钢绞线的中丝而得到的GFRP-OFBG智能钢绞线,进行了应变传感、温度敏感和钒绞线松弛试验,试验结果表明,GFRP—OFBG智能钢绞线具有优异的线性传感性能和较低的应力松弛率,并可实现钢绞线受载全过程监测,绞线中光栅测量应变极限为11568.2με,光栅波长变化为15.966nm;对直接增加GFRP—OFBG筋制成的光纤光栅平行钢丝智能索和直接增加GFRP-OFBG智能钢绞线得到的光纤光栅平行钢绞线智能索,进行荷载传感试验,试验结果表明,智能索的感知线性度和重复性都比较好,并可监测70%以上公称破断索力。智能索工程应用案例表明,GFRP—OFBG筋智能拉索在实际工程中很容易得到车辆荷载下的响应曲线。  相似文献   

3.
基于RSSI的无线传感器网络加权质心定位算法   总被引:60,自引:0,他引:60  
节点定位是无线传感器网络中的关键技术之一.文中通过对无线电传播路径损耗模型的分析,提出了加权质心定位算法,用信标节点对未知节点的不同影响力来确定加权因子,以提高定位精度.并且在理论分析的基础上,提出了优选信标节点进行节点定位计算的规则,以此进一步提高节点定位精度.加权质心定位算法计算简单,定位过程中节点问无通信开销.节点定位精度较常用的极大似然估计算法高,具有较普遍的应用意义.  相似文献   

4.
针对高速磁浮列车悬浮间隙传感器的温度漂移现象,建立了基于RBF(radial basis function)神经网络的间隙传感器温度补偿模型.通过对全局最优粒子执行梯度下降寻优,将粒子群优化算法与梯度下降算法结合得到一种寻优能力更强的混合算法,并将该方法用于RBF温度补偿模型参数优化,提高了间隙传感器的补偿精度,最后,使用现场可编程门阵列FPGA(field-programmable gate array)实现了该补偿模型并进行了实验.实验结果表明:该方法能够较好地对间隙传感器进行温度补偿,补偿后的传感器输出不受环境温度影响,全量程范围内最大误差为0.45 mm,8~12 mm工作间隙范围内误差为0.16 mm.   相似文献   

5.
在OFDM系统中,影响其性能的一个重要参数就是最大多普勒频移.本文根据功率谱估计原理,首先通过对接收到的含有最大多普勒频移(fm)信息的导频信号进行快速傅立叶变换(FFT),再利用衰落信道功率谱的分布来估计出最大多普勒频移信息.仿真结果表明,此方法可以有效地估计多普勒频移,并且具有实现简单和受噪声影响小的优点.  相似文献   

6.
针对我国中西部地区雷达未实现多重覆盖,大部分飞机未配备广播式自动相关监视(automatic dependent surveillance-broadcast, ADS-B)机载设备,监视精度不高的问题,结合雷达误差模型理论,提出了基于ADS-B数据的雷达误差实时校正算法.该算法对同一时刻获得的多组ADS-B数据与雷达数据的差值进行数据融合,得到该时刻雷达误差的最优估计值,并对雷达进行误差校正.算例仿真结果表明:经该算法校正后,雷达测量的距离与真实距离之间的均方根误差约为50 m,测量的角度与真实角度之间的均方根误差约为0.04°,且校正后的航迹和真实飞行航迹基本重合.   相似文献   

7.
针对高速路OD矩阵的采集与估计,提出采用RFID技术的车联网进行部署,建立有缺失数据的OD矩阵采集方法.用拉格朗日乘数法求解OD矩阵元素概率的极大似然估计,给出基于EM算法的OD矩阵估计算法.通过912节点规模的仿真实验结果表明,提出的算法相比模拟采集准确性更高,真实数据的均方根误差降低了77.7%,验证了算法流程和模型的有效性.   相似文献   

8.
The virtual backbone is an approach for solving routing problems in wireless ad hoc and sensor networks. A connected dominating set (CDS) was proposed as a virtual backbone to improve the performance of wireless networks. The quality of a virtual backbone is measured not only by approximation factor, which is the ratio of its size to that of minimum CDS, but also time complexity and message complexity. In this paper, a distributed algorithm is presented to construct a minimum CDS for ad hoc and sensor networks. By destroying triangular loops in the virtual backbone, the proposed algorithm can effectively construct a CDS with smaller size. Moreover, our algorithm, which is fully localized, has a constant approximation ratio, linear message and time complexity, and low implementation complexity. The simulation results and theoretical analysis show that our algorithm has better efficiency and performance than conventional approaches.  相似文献   

9.
点云配准是点云数据处理的关键,直接影响最后合成结果和模型精度。目前,点云配准方法普遍存在对配准数据初始位姿要求高的缺点。将点云配准分为两个阶段:第一阶段是基于同名点配准,即粗配准,采用人机交互式,配准过程耗时短,节约时间;第二阶段是精配准,在粗配准后,依据最小二乘原理,用间接平差思想,通过最近点迭代算法对点云数据快速配准,并采用目标点集中、目标点坐标与转入目标点集中的点坐标中误差为指标,评价配准精度。进行粗配准的精配准不仅速度快、耗时短,并且可以避免因局部收敛而带来的局部最小问题。试验表明该方法有效可行。  相似文献   

10.
针对单一粒子群算法的派梯策略优化运算过程中容易陷入局部极值点的状况,结合模拟退火理论,提出一种改进型的粒子群电梯群控派梯策略,应用到目的层预约的电梯群控系统中.通过仿真和对比试验可知,基于目的层预约的电梯群控系统能有效地提高服务的各项指标,改进型的粒子群电梯群控调度策略可有效减小乘客候梯时间和电梯启停次数,改善电梯运行性能.  相似文献   

11.
To handle the problem of target tracking in the presence of standoff jamming (SO J), a Gaussian sum unscented Kalman filter (GSUKF) and a Gaussian sum particle filter (GSPF) using negative information (scans or dwells with no measurements) are implemented separately in this paper. The Gaussian sum likelihood which is derived from a sensor model accounting for both the positive and the negative information is used. GSUKF is implemented by fusing the state estimate of two or three UKF filters with proper weights which are explicitly derived in this paper. Other than GSUKF, the Gaussian sum likelihood is directly used in the weight update of the GSPF. Their performances are evaluated by comparison with the Gaussian sum extended Kalman filter (GSEKF) implementation. Simulation results show that GSPF outperforms the other filters in terms of track loss and track accuracy at the cost of large computation complexity. GSUKF and GSEKF have comparable performance; the superiority of one over another is scenario dependent.  相似文献   

12.
单ESM传感器对运动目标的快速定位方法   总被引:2,自引:2,他引:0  
研究了机载单ESM传感器对运动目标的定位问题.建立了单ESM传感器平台作航向机动时对运动目标定位的数学模型以及相应的求解方法,克服了单ESM传感器平台做直线运动时对运动目标观测存在不可观测的局限性,对于ESM平台作航向机动和匀速直线运动情况具有普遍适用性.理论分析和仿真结果表明:文中提出的算法,能够迅速有效地对运动目标进行定位,并具有较高的定位和跟踪精度,航向机动量越大,对目标的定位精度越高.  相似文献   

13.
In this paper, we proposed a registration method by combining the morphological component analysis (MCA) and scale-invariant feature transform (SIFT) algorithm. This method uses the perception dictionaries, and combines the Basis-Pursuit algorithm and the Total-Variation regularization scheme to extract the cartoon part containing basic geometrical information from the original image, and is stable and unsusceptible to noise interference. Then a smaller number of the distinctive key points will be obtained by using the SIFT algorithm based on the cartoon part of the original image. Matching the key points by the constrained Euclidean distance, we will obtain a more correct and robust matching result. The experimental results show that the geometrical transform parameters inferred by the matched key points based on MCA+SIFT registration method are more exact than the ones based on the direct SIFT algorithm.  相似文献   

14.
Accurate registration of chest radiographs plays an increasingly important role in medical applications.However, most current intensity-based registration methods rely on the assumption of intensity conservation that is not suitable for alignment of chest radiographs. In this study, we propose a novel algorithm to match chest radiographs, for which the conventional residual complexity(RC) is modified as the similarity measure and the cubic B-spline transformation is adopted for displacement estimation. The modified similarity measure is allowed to incorporate the neighborhood influence into variation of intensity in a justified manner of the weight, while the transformation is implemented with a registration framework of pyramid structure. The results show that the proposed algorithm is more accurate in registration of chest radiographs, compared with some widely used methods such as the sum-of-squared-differences(SSD), correlation coefficient(CC) and mutual information(MI)algorithms, as well as the conventional RC approaches.  相似文献   

15.
文中阐述了采用1985年7月4日和8月5日的陆地卫星TM数据对纽约州西里卡县进行农作物自动分类的研究。农作物主要指玉米和小麦。使用监督的最大似然率数字图象分类法。分类结果的精度:玉米为72~91%的正确分类率,小麦为82~88%的正确分类率,同时分类的附加误差很小。文中对如何选择训练数据,以提高分类的精度和可靠性作了研究。  相似文献   

16.
独立分量分析原理及其应用   总被引:3,自引:0,他引:3  
综述了独立分量分析(ICA)的基本原理及基于信息最大化原理的各种方法及其特性,介绍了HJ网络、基于信息最大化的Infomax法及其扩展算法、极大似然估计(MLE)法、负熵最大化法、基于高阶累量的ICA法和Dussage法,对各种方法性能做了比较,说明了ICA在生物医学信号处理中的应用,并对ICA的发展作了展望.  相似文献   

17.
视角受限传感器网络强栅栏覆盖判定算法   总被引:2,自引:0,他引:2  
栅栏覆盖研究如何分配网络时空资源来确保移动目标穿越监控区域时被监测.本文通过视角受限节点传感方向的调整,设计一种分布式算法以判定网络能否提供强栅栏覆盖.算法主要思想是利用节点及邻居节点的物理位置关系构建强/弱栅栏对.另外,本文设计贪心策略优先选择邻居节点数多的候选节点构建强栅栏路径.仿真实验证明:本算法可以较小代价判定并改善网络强栅栏覆盖性能.  相似文献   

18.
针对WSN节点定位中非测距DV-HOP算法存在较大定位误差,提出了一种多通信半径误差修正自适应布谷鸟优化DV-HOP定位算法(MEACS-D). 采用锚节点多通信半径广播消息,在跳数计数时将跳数小数化,以减小跳数长短不一造成的误差;再用虚拟相交圆几何方法计算1跳内节点与锚节的距离;通过在未知节点选择平均跳距时,加入各个锚节点权重进行计算来减少平均跳距误差;另引入可自适应搜索步长的布谷鸟算法代替极大似然估计法来定位节点坐标,以提高定位精度. 通过仿真,在不同锚节点、通信半径、总节点条件下MEACS-D算法较DV-HOP算法和原布谷鸟DV-HOP算法(CS-D)算法定位误差平均下降39.7%、10.6%,证明MEACS-D算法能有效减少定位误差.   相似文献   

19.
针对现行结构损伤检测方法仅考虑了环境和荷载对损伤的影响,未考虑传感器因时间和环境变化导致的性能退化从而严重影响损伤诊断率的问题,考虑到传感器性能退化的局部性及结构损伤的全局性,利用最小均方差估计与广义极似然比(GLRT)理论检测结构响应异常,结合统计质量控制图的控制指标超出界限的波动样式判断异常来源,并通过简支梁数值算例验证了本文提出的方法.研究结果表明:利用广义极似然比可以有效检测响应异常,利用控制图可以辨别响应异常来源;传感器性能退化导致控制指标超出界限的波动为非平稳波动,而损伤导致控制指标在一定范围内的波动为平稳波动.   相似文献   

20.
An improved list sphere decoder (ILSD) is proposed based on the conventional list sphere decoder (LSD) and the reduced- complexity maximum likelihood sphere-decoding algorithm. Unlike the conventional LSD with fixed initial radius, the ILSD adopts an adaptive radius to accelerate the list cdnstruction. Characterized by low-complexity and radius-insensitivity, the proposed algorithm makes iterative joint detection and decoding more realizable in multiple-antenna systems. Simulation results show that computational savings of ILSD over LSD are more apparent with more transmit antennas or larger constellations, and with no performance degradation. Because the complexity of the ILSD algorithm almost keeps invariant with the increasing of initial radius, the BER performance can be improved by selecting a sufficiently large radius.  相似文献   

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