航迹规划中雷达探测空间的生成

从飞机突防习行任务规划出发，综合考虑地球曲率、陆地（或海洋）的反射和杂波干扰、大气折射和吸收损耗等因素的影响，采用临界散射截面法生成了对空警戒雷达在不同地貌、发现概率下，对不同雷达散射截面的目标的探测空间。计算并分析了飞行高度、目标雷达散射截面、发现概率和地貌等因素对雷达探测空间的影响，以便选择低探测概率的飞行走廓，这对制定和实施安全突防飞行策略有实际意义。     

航迹规划中反舰巡航导弹的雷达突防能力

在导弹航迹规划中，需要计算导弹突防过程中被雷达发现的概率。为此，在雷达方程中引入雷达系统特征常数以简化雷达方程，从探测概率与信噪比的关系出发，通过一系列的推导并考虑杂波的影响得出探测概率与目标距离的关系，提出在航迹规划中用横距探测概率来表征反舰巡航导弹的雷达突防能力。算例计算结果较为真实，表明该方法有一定应用价值。     

闪光雷达中APD探测性能分析

针对闪光雷达,给出了一种分析雪崩光电二极管(ADD)探测性能的方法.通过理论推导及仿真的方法,对APD接收到信号光功率、探测器的噪声、信噪比以及APD的探测性能进行了分析.结果表明.通过选择合理的APD增益,可提高的信噪比和探测概率,通过增大APD探测阈值,可以降低虚警概率.     

美式电子篱笆对空间目标检测概率的计算

为了检验美式电子篱笆对空间目标的探测能力,本文以电子篱笆系统对空间目标的检测概率作为研究对象,结合空间目标运行仿真和雷达探测仿真两个领域,通过空间目标轨道运动、雷达接收信噪比和雷达检测概率计算等数学模型计算此系统对穿越的空间目标的检测概率,从检测概率的角度给出了电子篱笆的性能评估。然而检测概率并不等同于捕获概率,所以进一步的研究工作可在对有用信号提取成功的概率方面开展。     

从探测概率的角度评价飞机的隐身性能

采用雷达散射截面(RCS)均值来衡量飞机的隐身性能并不能给出足够充分的信息,从信号检测概率的角度来衡量飞机的可探测性可以提供更完整的信息。本文从探测概率的角度详细分析了4种典型隐身飞机RCS起伏数据与虚警概率、探测概率、探测距离、信噪比(SNR)等参数间的关系,并给出了完整的推导过程,采用此方法可以对任意飞机目标在给定雷达参数下的可探测性进行准确计算。一般在雷达性能评估中需要用到RCS起伏模型,本文对飞机目标回波信号进行检测分析时采用数值计算方法,信号的概率密度函数(PDF)直接来源于原始回波起伏信号,避免了模型拟合带来的回波特性失真,且不会产生大的计算误差。通过对比分析计算结果发现:单脉冲检测下回波信号均值中值比越大,回波取值范围越小,则信号的检测概率越小,其中均值中值比一般相差3倍以上时可以得到明显不同的检测概率;在快起伏假设下,非相参积累检测的积累脉冲数Nin即便较小,也能得到较大的信噪比增益,此增益可能大于Nin。     

飞行器对下视PD雷达隐身性能计算方法

通过研究杂波频谱密度与等多普勒线对应角度的关系，推导了目标信号落在旁瓣杂波频谱不同位置时临界散射截面的算法．在无需知道ＰＤ雷达脉冲积累数的情况下，得到了ＰＤ雷达载机与目标飞机以任意姿态遭遇时、对应于任何发现概率的临界散射截面的计算方法．经分析算例表明，如果战斗机或攻击机既具有超音速巡航能力又采用了隐身技术，将对敌方的下视警戒系统构成威胁．     

单脉冲跟踪雷达多目标检测算法性能分析

对2种检测单脉冲雷达主波束内是否存在2个不可区分目标的算法进行了推广,将其应用到波束内可能存在N个不可区分的目标,并仿真了波束内存在3个目标时的检测性能。仿真表明,在总信噪比相同时,3个目标的检测概率不一定大于2个目标的检测概率,处于方位向上间距最大的2个目标的信噪比对整个检测概率影响较大。     

超大尺寸共形吸波体雷达散射截面分析及验证

受结构复杂、超大尺寸、制作工艺等多种条件的限制,超大尺寸共形吸波体装机应用后的雷达散射截面研究开展较少,亟需从仿真及试验两个方面加强研究。本文从超大尺寸共形吸波体的双马来酰亚胺材质隐身翼面前缘制作工艺和基于仿真评估的结构设计出发,对共形吸波体的分层结构参数进行优化,对机翼前缘共形吸波体的装机雷达散射截面进行试验验证。结果表明：本文设计的超大尺寸共形吸波体垂直极化下在2~18GHz 取得-1.1~-22.4 dB 的雷达散射截面减缩效果,雷达散射截面的仿真评估误差可以控制在6.5 dB 以内,其中材料的电磁参数各向异性测试对仿真误差有决定性影响。     

湍流等离子体尾迹雷达散射截面的计算及其影响因素分析

针对一阶畸变波Born近似模型,深入分析了湍流内外尺度和电子数密度脉动值对雷达散射截面的影响,并且给出了关于湍流外尺度的一个经验的,能被工程上较好使用的公式.在以上分析的基础上,计算了几种高程条件下再入小钝头锥体等离子尾迹的雷达散射截面,与已有实验结果进行了对比分析.分析和计算结果表明,湍流的外尺度和局部电子数密度值对雷达散射截面值影响较大;湍流内尺度变化的影响不大.     

基于Agent理论的飞机敏感性评估方法

在以信息战为核心的现代战争中,各机种、多平台之间的信息交互成为影响战争结果的关键因素。因此进行飞机敏感性设计时,应当置于信息对抗的环境中并考虑信息交互过程。本文阐述了网络中心战的理论,建立了基于Agent理论的战场模型以及飞机对抗模型,通过对Agent对抗过程中的3个阶段（探测阶段、信息交互阶段、作战阶段）进行建模仿真,研究了预警机探测能力、飞机雷达散射截面（RCS）、信息传输时延和红外电子对抗能力等因素对飞机敏感性的影响,得到了雷达特征参数、飞机RCS与探测概率之间的关系,传输时延与先敌发射概率之间的关系,以及红外干扰弹的最优发射区间,为飞机的敏感性设计提供了一定的依据。     

关于低RCS目标外形优化中目标函数的确定

在分析了低RCS目标外形优化中现有的两种目标函数的局限性的基础上,根据雷达检测概率与目标RCS分布之间的关系,提出了一种新的目标函数,即目标在威胁区域内其RCS大于规定的临界RCS的概率。算例表明本文所提出的目标函数比现有的目标函数更为有效,适用范围更广。为低RCS目标外形优化设计以及气动与隐身一体化设计提供了一个合理而有效的目标函数。     

The Jet Fighter Radar Cross Section

Two jet fighter models, 1/8th of original size, have been measured in the "radar range" installed in the anechoic chamber of the Armament Technology and Procurement Group in Berne. The measurements have been made at a frequency of 40 GHz (5 GHz for full scale), with an accuracy of ± 2 dB and a dynamic range of 80 dB. The statistical distribution of the radar cross section has been calculated with the help of a computer, based on the measured data. The detection probability has been calculated with the help of a correlation procedure. This procedure allows explanation of the symmetry relation between the detection probability and the cumulative distribution of the radar cross section, and of a well-known characteristic of the median value of the radar cross section. A statistical model is proposed for the distribution of the radar cross section of jet fighters, consisting of the distribution of a spheroid in which each element itself exhibits a Rayleigh fluctuation. This model presents a certain number of interesting characteristics, and there is an acceptable degree of coincidence with the measured values.     

Probability of Detecting a Swerling I Targetet on Two Correlated Observations

Modern radars characterized by electronically steered beams, frequency agility, and range-ambiguous waveforms can use a processing technique whereby each new detection is followed by a second dwell to verify the initial detection. The second dwell is used to minimize false alarms and to resolve range and/or Doppler ambiguities. Under the assumption of a Swerling I target model, the target cross section remains constant when both dwells occur on the same scan and the same transmission frequency is used. Analytic expressions have been developed for the probability of detecting a Swerling I target on both of the correlated dwells (same target cross section). These expressions are used to calculate the probability of a second dwell detection given a first dwell detection and the probability of at least one detection on two dwells. These probabilities are compared with those of independent dwells (independent target cross sections) which result when two transmission frequencies of sufficient separation are utilized.     

Probability of Detecting Aircraft Targets

The statistics of aircraft radar cross section (RCS) are estimated by fitting members of the chi-square family of distributions to empirical distributions obtained from blocks of RCS data, each block of data corresponding to a particular aircraft azimuth aspect. The parameters of the fitted distributions vary with azimuth aspect angle, type of aircraft, and radar frequency. Detection probabilities based on the estimated statistics are calculated and compared with detection probabilities based on Rayleigh statistics. This comparison indicates that the average value of radar cross section has much more effect on probability of detection than the normalized variance of RCS, and in the usual situation tends to mask the effect of the normalized variance on probability of detection.     

Calculation of probability of detection for log-normal targetfluctuations

An accurate, simple, and reliable method for the computation of the probability of detection for a target whose radar cross section is constant within a scan but fluctuates log-normally scan-to-scan is presented     

Probablity of Detection for ICW Radars

Eclipsing of received signals is analyzed for Interrupted Continuous Wave (ICW) radars. A probability density for the Signal to Noise Ratio (SNR) at the Doppler filter output is derived which incorporates eclipsing effects and a fluctuating target cross section model. The probability of detection as a function of SNR is calculated for typical ICW parameters and the magnitude of the detection loss due to eclipsing is assessed     

Calculation of Probability of Detection with Target Scintillation

This paper presents a computational method for the calculation of probability of detection using measured radar target cross-section data. The described method can also be used for probability of detection calculations when the radar target cross section follows a specified probability density function. Using the computational procedure of the paper, a number of curves are generated which can be used for probability of detection calculations with exponential and Gaussian radar target cross-section distributions. The results obtained using theoretical distributions are compared with the corresponding results using actual target cross-section measurements. The results of computer runs are compared to the corresponding values in the literature where available.     

隐身飞机在大仰角时的生存力评估

介绍了生存力基本概念;给出了飞机发现概率的计算;在缺少某些雷达参数时,所提出的发现概率计算方法仍然适用。讨论了几种减缩RCS的实际可行的方法,并就隐身设计给出了指导性的意见。