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61.
泛探雷达长时间相参积累目标检测方法研究   总被引:1,自引:0,他引:1       下载免费PDF全文
泛探雷达利用同时多个接收波束覆盖整个观测空域,可利用长时间相参积累提高动目标检测性能,然而必须解决目标在长积累时间之内出现跨波束、跨距离单元和跨多普勒单元现象带来的积累增益下降问题。在跨波束影响可忽略前提下,研究了基于Keystone变换与Dechirping变换相结合的运动补偿方法,并在此基础上提出了基于Clean思想的多目标检测流程。通过对仿真数据与外场实测数据的处理与分析,验证了本文方法的有效性,可以用于泛探雷达的目标检测。  相似文献   
62.
由于海洋环境的复杂性和水声信道的特殊性,多目标跟踪过程中的目标威胁评估一直是水声信号处理领域的突出难题.目标威胁度是目标分配的重要依据,必须综合考虑目标的多种特征信息.针对水下声自导系统,提出了目标威胁度评估指标体系,构建隶属度函数对各个指标进行了量化,并建立了基于模糊折衷的目标威胁度综合评价模型.仿真结果证明该方法能有效节省航程,为提高水下航行器的作战效能提供了有效途径.  相似文献   
63.
为了对机动目标进行ISAR成像,以在时间和频域同时具有高分辨率的时频变化替代傅氏变换作谱分析,得到机动目标距离—瞬时多普勒像。实测数据处理结果表明,与直接用距离—多普勒(R D)算法相比,该方法得到的图像质量有明显提高。  相似文献   
64.
为有效地对战争目标情报进行快捷、准确地分析处理,从而确定目标区域战场价值程度,以炮兵某次进攻战斗为战术背景,将敌防御区域按照目标分布特点划分为12个小区域;再根据目标的属性和打分原则,运用打分法分别求出各个小区域的综合得分情况;最后采用模糊聚类分析方法和Excel应用软件对其价值进行分析评估,依据模糊聚类结果从而确定重点区域,为指挥员和决策机关制定正确的策略提供科学的依据。  相似文献   
65.
通过对时间上敏感的目标的分析确定,打击过程的指挥与控制及注意事项的研究,对一体化作战行动的联合目标选择与打击的相关问题进行了探讨.  相似文献   
66.
Up to the present, there is only very little research on how the population perceives terrorism and its threats, even though support from the population is crucial for effective counterterrorism. By eliciting beliefs and subjecting them to content analyses, six factors were found that determine the protection worthiness of a target in the people's view: the potential damage to “people,” “symbolism,” “economy,” “politics,” “nature,” and “image/publicity.” These empirically found factors are in line with factors specified by terrorist target selection models. They differ in the strength of their cognitive representation among participants and, thus, their subjective importance to the people. The first three factors are shared among all participants, whereas the latter ones could only be found in a part of the participant sample. People's judgments of the targets' protection worthiness differ substantially from their judgments of the targets' attractiveness to terrorists, even though the same factors seem to be involved. This study offers an insight into the people's mental model about protection worthiness of targets. Together with classical risk analysis and knowledge about terrorists, these results can form a basis for setting up a holistic scheme for critical infrastructure protection.  相似文献   
67.
《防务技术》2022,18(9):1622-1642
Steel-tube-confined concrete (STCC) targets are provided with excellent anti-penetration performance over semi-infinite concrete (SIC) targets since the steel tube imposes passive restraint on the in-filled concrete during the penetration process. Grid STCC system with square steel tubes is a potential solution to protective structures. In this paper, experiments of 9-cell grid STCC targets penetrated by 12.7 mm Armor Piercing Projectile (APP) were performed. The influence of side length and thickness of steel tube, steel ratio and impact velocity on anti-penetration performance were taken into account. Additionally, single-cell square STCC targets were also designed and tested for comparison with the 9-cell grid STCC targets. Damage modes and parameters of the tested targets were measured and discussed. Moreover, the stiffness of radial confinement of grid STCC targets is achieved according to the elastic solution of infinite cylindrical shell in Winkler medium. Furthermore, the penetration resistance and depth of penetration (DOP) for grid STCC targets are obtained on the basis of the dynamic finite spherical cavity-expansion (FSCE) models including radial confinement effect. It is shown that the 9-cell grid STCC targets with optimal dimension match of thickness and side length of steel tube can reduce the DOP by about 17 % and 23 % in comparison with the SIC targets and single-cell square STCC targets, respectively, due to both the confinement of square steel tube to concrete in the impacted cell and the additional confinement of the surrounding cells to the impacted cell; the penetration resistance and DOP of the grid and cellular STCC targets with similar steel ratio is close, and thus the grid STCC targets with simpler manufacturing process and excellent in-plane expandability are preferred in engineering practice; moreover, the predicted results of DOP model based on the FSCE models agree well with the tested results with the maximum disparity less than 12 % and the proposed model is more applicable to the grid and cellular STCC targets with high radial confinement.  相似文献   
68.
通过对传统的联合概率数据关联算法(JPDA)在平行临近及小角度交叉目标的关联跟踪中引起的航迹合并问题的分析,提出了一种基于最大交互概率的改进比例联合概率数据关联算法.该算法找出距离两逼近目标的交互概率中心最近的有效观测,引入一比例因子对该观测与所有目标的关联概率进行修正,将逼近目标“拉开”,从而抑制了航迹的合并.仿真结...  相似文献   
69.
基于间歇采样转发干扰理论,提出了一种ISAR二维群目标生成方法。采用伴飞式干扰机,对所掩护的目标回波信号进行间歇采样转发,在ISAR上形成逼真的虚假二维群目标图像;通过调整干扰机和目标的空间位置关系,生成二维假目标序列,并能模拟目标的动态姿态变化。在介绍了间歇采样转发干扰的基本原理后,阐述了伴飞式干扰原理,然后从理论上推导了了伴飞式干扰机的功率和空间位置要求,接下来着重分析了二维群目标生成的理论原因,指出了影响二维群目标分布的关键因素和群目标的姿态角变化规律,最后进行了仿真验证,结果表明了该方法的有效性。研究成果对于ISAR干扰机的设计和工程应用具有指导意义。  相似文献   
70.
本文中讨论由若干个相依目标群组成的平面点目标系统的火力分配问题。对于武器型号相同的情形,得到了“边际毁伤递减原理”和“循序最优方案即全局最优方案”等结论,并在此基础上提出了问题的解算方法。对于武器型号不同的情形,提出了“循序最优枚举法”,并得出有关结论。  相似文献   
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