基于小波分析的激光探潜技术

介绍了利用小波分析的方法对水下目标的回波信号进行去噪声、检测及定位．模拟结果表明,该方法的时频可变性有效地克服了传统方法的不足．     

激光制导航空炸弹攻击区仿真计算

针对某型激光制导航空炸弹,进行了典型条件下的攻击区仿真计算,得出了几点结论。研究的方法和结论,可供研究激光制导武器参考,为进一步研究其它条件下投放激光制导武器的攻击区打下基础。     

等离子体粒子模拟中的改进型Borris旋动粒子方法

将等离子体粒子模拟中得到广泛应用的Borris旋动粒子方法进行了改进,用于精确求解相对论Lorentz运动方程。这种改进型Borris旋动方法在模拟粒子在强磁场中的动力学行为时仍具有相当高的计算精度,且耗费计算量较小。将改进型Borris旋动方法应用于等离子体粒子模拟中,尤其适用于模拟超强激光与等离子体的相互作用。     

烧蚀材料对辐射烧蚀驱动的Richtmyer Meshkov不稳定性影响

在惯性约束聚变靶丸内爆过程中,辐射烧蚀所产生的冲击波经过带有扰动的界面时,会触发Richtmyer-Meshkov不稳定性。惯性约束聚变内爆靶丸一般使用掺杂的CH塑料或者掺杂的Be材料作为烧蚀层,为了探索Be和CH塑料烧蚀层对Richtmyer-Meshkov不稳定性抵抗能力,对界面预制单模正弦扰动的双层靶中Richtmyer-Meshkov不稳定性发展过程进行了理论分析与数值模拟。理论分析认为Richtmyer-Meshkov不稳定性线性增长率和X射线辐射温度、界面扰动波长、扰动振幅以及烧蚀层密度有较大关系。使用辐射流体力学程序对辐射温度高达100 eV的黑体谱X射线烧蚀界面带有扰动的双层靶进行了模拟。模拟结果表明,在相同的辐射烧蚀条件下,CH塑料/泡沫(CH/Foam)靶界面扰动增长比Be/Foam快,密度较大的Be对Richtmyer-Meshkov不稳定性具有更强的抵抗能力。该研究结果对惯性约束聚变内爆靶丸的设计具有重要的参考价值。     

基于主动相位控制的脉冲激光相干合成技术

提出并验证了基于随机并行梯度下降(SPGD)算法的主动相位控制脉冲激光相干合成方案.利用低通滤波器滤除脉冲激光光强变化导致的性能评价函数起伏,提取出相位噪声导致的性能评价函数变化,然后将这个低通滤波后的性能评价函数用于SPGD算法的极值寻优过程,从而实现脉冲激光的锁相.对该方案进行了理论分析和数值模拟,并进行了两路脉冲激光相干合成实验.实验结果表明,当系统从闭环到开环时,系统性能评价函数均值提高到开环的1.6倍,干涉条纹长曝光对比度从0提高到0.43.在该方案中,通过增加合成脉冲激光路数,并在各路脉冲激光中引入多级功率放大器,能够得到更高的合成功率输出.     

激光照射指示器束散角数字化检测方法研究

激光末端制导武器系统中,激光照射指示器出射激光的束散角是一个重要的参数。介绍了一种出射激光束散角的数字化检测方法。区别于传统的套孔法和反射靶板法,该方法通过CCD采集激光光斑,用质心法确定光斑中心,根据激光能量密度分布确定激光光斑半径,进而计算出待测的激光束散角。     

光纤激光水听器的PGC实时全数字解调系统

概述了基于麦克尔逊干涉仪的光纤激光水听器的相位载波零差法(PGC)调制解调原理,通过数学推导及仿真,分析了调制信号和混频信号的频差是导致全数字化解调结果错误的主要因素之一。针对该诱导因素提供了可行的解决方案,并实现了基于DSP的1 MHz采样频率下使用PGC方法的全数字实时解调系统。对低频水声波段800Hz水声信号进行解调,实验结果表明:解调信号波形良好。     

泰氟隆烧蚀产物对电子密度的影响

采用WNND格式,对有泰氟隆烧蚀产物引射的化学非平衡NS方程进行了数值模拟。采用7组元纯空气化学反应和19组元、28种反应的空气—泰氟隆化学反应系统,对照计算了壁面有泰氟隆烧蚀产物引射和纯空气绕流两种流场,研究了泰氟隆烧蚀产物对电子密度的影响。     

Electronic warfare in the optical band: Main features,examples and selected measurement data

The paper presents the possibilities of, and methods for, acquiring, analysing and processing optical signals in order to recognise, identify and counteract threats on the contemporary battleground. The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated, including the acquisition of optical emitter signatures, as well as ultraviolet (UV) and thermal (IR) signatures. The physical parameters and values describing the emission of laser radiation are discussed, including their importance in terms of creating optical signatures. Moreover, it has been shown that in the transformation of optical signals into signatures, only their spectral and temporal parameters can be applied. This was confirmed in experimental part of the paper, which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders. It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in “solar-blind” band, various events can be identified quickly and faultlessly. The same is true for IR signatures, where the amplitudes of the recorded signal for several wavelengths are compared. This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground, namely Rocket Propelled Grenade (RPG) launches and explosions after hitting targets, trinitrotoluene (TNT) explosions, firing armour-piercing, fin-stabilised, discarding sabots (APFSDS) or high explosive (HE) projectiles. The final section describes a proposed model database of emitters, created as a result of analysing and transforming the recorded signals into optical signatures.     

舰载烟幕弹的最佳使用时机

针对激光制导反舰导弹的作战使用过程 ,依据侦察探测的倒立方律及对导弹的捕捉概率 ,探讨舰载烟幕弹的最佳使用时机问题 ,指出应充分利用舰艇 C3I系统的综合信息 ,由舰指挥员负责实施