ID 原文 译文
13124 针对HF定频信道探测杂波背景下的检测问题，提出了一种基于瑞利分布映射的阈值提取方法，并根据多层次阈值提取结果和基于游程码的二值图像标记及图像膨胀填充方法，给出了 HF定频信道杂 波背景能量层次轮廓（文中统称背景分割方法），为后续的检测研究提供支持。 Aiming at the detection problem of HF fixed-frequency channel detection clutter background, a threshold extraction method based Rayleigh distribution map is proposed, and accordmg to the multilevelthreshold extraction result and the binary image mark and image expansion filling method based on rurrlength code, the background energy [evel profile of HF fixed frequency channel clutter is given, which provides support for subsequent detection research.
13125 研究表明，本方法在多种HF定频信道探测的杂波背景分割中，均能给出较理想的杂波背景轮廓，对后续的海杂波提取及相关检测有一定的指导作用。 The research shows that this method can give an deal clutter background contour in the clutter in the clutter background segmentation of multiple HF fxed-frequency channel detecton, wch has a certain guding effect on the subsequent sea clutter extraction and correlation detection.
13126 基于2014—2016年发布的全球电信系统(global telecommunication system, GTS)数据，对南海海域附近8个探空站数据进行了统计分析，获得了南海海区低空大气波导参数统计特征以及概率分布特征结果。 Based on the Global Telecommuncaton System(GTS) data Hrom 2014 to 2016 , a statstical analysis from eight radiosonde stations data near South China Sea(Scs)s gSen in this paper. We obtained the annual duct parameters and probablty dstrbuton characteristics of the lower atmospherc ducts.
13127 结果表明：年度统计来看,南海海区表面波导发生概率在20%左右，大部分表面波导高度位于100 m 以下，强度小于10 M，悬空波导发生概率在50%左右，悬空波导顶高、层底高、底高参数一般位于1 000〜 2 500 m，强度位于4 M〜15 M，空间分布基本呈现中部高、南北低(与热带辐合带相关)的特点。 Annual statstcs show that the probablty oH surHace duct occurrence Fn the South Chna Sea Fs about 20% , and most surface duct heights are below 100 m and the duct intensity is smaller than 10 M. The probabllity of elevated duct occurrence is about 50%. The parameters of top height, bottom height and bottom height of elevated duct are generally between 1 000 and 2 500 m, and the intensity is 4 M —15 M. The spatial distribution of atmospheric duct is high in the middle part and low in the north and south part, which is related to the inter tropical convergence zone (ITCZ).
13128 月份统计来看，南海北部以及中部具有明显的月份变化(与南海季风密切相关)，而南海南部(靠近赤道)月份变化则不明显。 Monthly statistics show that there are obvious monthly variations In the northern and central South Chna Sea, which closely relates to the South Chna Sea monsoon, while the variations are not obvious in the southern South China Sea area (the area near the equator).
13129 统计分析结果可为南海海区雷达、通信系统的运行保障提供参考。 These statistical analysis results can serve as a reference for radar and communication system working or operating in this sea area.
13130 针对雷达探测临近空间高超声速目标模拟试验中的雷达散射截面(radar cross section, RCS) 逼真模拟问题，提出了一种适用于临近空间高超声速飞行器等离子体鞘套下目标RCS衰减模拟方法。 In order to solve the problem of radar cross section(RCS) simulation in the simulation test of radar detecton of hypersonc target in near space , a target RCS reducton simulaton method sutable for near space hypersonc vehicle under plasma sheath is proposed.
13131 首先，利用不同高度、不同速度对应的等离子体频率和电子碰撞频率的相关数据，拟合得出不同速度、不同高度对应的等离子体频率和电子碰撞频率关系表。 Firstly, based on the relevant data oH plasma frequency and electron collision frequency corresponding to different altitude and velocity, the relaton- ship table of plasma frequency and ebsctron coliision frequency corresponding to different velocity and altitude was fitted.
13132 其次，实时查表得到给定雷达频率情况下不同目标高度与速度对应的等离子体频率和电子碰撞频率，建立目标等离子体包覆模型和电磁波传输模型，计算雷达电磁波的衰减 系数和反射系数。 Secondly, the plasma frequency and electronic collision frequency corresponding to different target altitude and velocty are obtained by real-time tab l e l ookup under given radar frequency. The target plasma coating mode! and ekctromagnetic wave transmission model are estabiished, and the attenuation coeffcent and reflecton coeffcent of radar electromagnetc wave are calculated.
13133 最后，通过雷达电磁波的衰减系数和反射系数模拟出目标RCs衰减。 Finally, the RCS reduction of target can be simulated by the attenuaton coefficient and reflection coefficient of radar electromagnetic wave.