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11.
为了提高教学效果,减少实装损耗,加强新装备保障能力,研制某型火控雷达维修训练模拟器;该模拟器以网络化主控计算机单元为核心,由实装操作分系统、虚拟装备分系统、实装部组件分系统、动感分系统、联动分系统组成,具有操作训练、维修训练、武器系统联动训练及训练评估等功能,解决了新型雷达装备教学与训练中实装损耗大、装备数量少、训练效率低等问题;该模拟器已用于多个雷达专业的操作、维修、综合演练等教学实践中,与以往的训练设备相比可操作性好,应用范围广,教学效果明显;文中介绍了模拟器的功能结构、硬件设计、软件设计及其应用。 相似文献
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Active cancellation stealth is a smart signal blanking method, that it has become an important developing direction on modern stealth technology. In order to further explore the active cancellation stealth technology, we are considering the detection and cancellation of receiving/transmitting antenna pattern is different. Put forward active cancellation system simulation structure diagram based on MATLAB/SIMULINK, where the phased array radar system as the modelling object, and established the active cancellation stealth system mathematical model based on digital radio frequency memory (DRFM) and the radar signal processing system of the coherent video simulation model, based on linear frequency modulation and radar coherent pulse signal simulation, verified the rationality and validity of the design, as the active cancellation stealth engineering technology laid the foundation. 相似文献
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Xianming Sun Haihua Wang Yiping Han Xiaowei Shi 《International Journal of Infrared and Millimeter Waves》2007,28(11):993-1001
A melting layer of precipitation is composed of melting snow particles, and we modeled them by three-layered spherical particles,
in which the innermost layer is air, the middle ice and the outermost water. Based on this model, the radar reflectivity,
together with the specific phase shift and the specific attenuation of a melting layer of precipitation, were computed at
1–100 GHZ by using the Mie theory. The radar bright band is explained by this model. We compared our numerical results with
that in the literature Zhang (IEEE Transactions on Antennas and Propagation 42(3):347–356, 1994), Zhang (IEEE Transactions
on Antennas and Propagation 42(3):492–500, 1994). It demonstrates that the three-layered snow sphere model is appropriate
and practicable, so the computed results are more accurate. This study can be used in radar remote sensing and satellite-earth
communications. 相似文献
18.
Wenqin Wang 《International Journal of Infrared and Millimeter Waves》2006,27(11):1433-1444
In remote sensing applications, there is a special interest in the lightweight, cost effective, and high resolution imaging
sensors. The combination of linearly frequency modulated continuous wave (LFMCW) technology and synthetic aperture radar (SAR)
technique can lead to such a sensor. This paper concentrates on the analysis of waveform errors in millimeter-wave (MMW) LFMCW
SAR. The generating scheme of millimeter-wave LFMCW waveforms with phase locked loop (PLL) and direct digital synthesizer
(DDS) combined frequency synthesizer is investigated. The impacts of quantization errors, spurs, and frequency nonlinearities
are analyzed. Simulation results show that the quality of LFMCW waveforms has a direct influence on the SAR images. Hence
a scheme of frequency synthesizer to achieve high performance MMW LFMCW waveform is proposed. This synthesizer driven by a
DDS array can adaptive suppress the spurious level without degradation of excellent frequency linearity and fast switching
speed. 相似文献
19.
为解决某雷达高度表试验过程中发生的动作高度测试异常故障,采用故障树分析法对雷达高度表和测试设备进行故障排查。经检测发现,测试设备上位机的串口通信卡接收下位机的数据中有几十帧数据帧出现CRC校验位错误,被应用程序丢弃。原因是下位机发出的数据信号存在一定程度的畸变,上位机串口通信卡的串口控制器芯片OX16PCI694适应性不足导致数据读取出错。而应用程序在健壮性设计上也存在缺陷,以数据帧数来计算时间及雷达动作高度,但丢弃数据帧时未作相应处理。采用兼容性好的串口控制器芯片16C554重新设计通信卡,在上位机与下位机通信协议中增加数据的帧序号。经试验验证故障定位正确,解决措施有效。 相似文献
20.
The infinite T-matrix method is a powerful tool for electromagnetic scattering simulations, particularly when one is interested in changes in orientation of the scatterer with respect to the incident wave or changes of configuration of multiple scatterers and random particles, because it avoids the need to solve the fully reconfigured systems. The truncated T-matrix (for each scatterer in an ensemble) is often computed using the null-field method. The main disadvantage of the null-field based T-matrix computation is its numerical instability for particles that deviate from a sphere. For large and/or highly non-spherical particles, the null-field method based truncated T-matrix computations can become slowly convergent or even divergent. In this work, we describe an electromagnetic scattering surface integral formulation for T-matrix computations that avoids the numerical instability. The new method is based on a recently developed high-order surface integral equation algorithm for far field computations using basis functions that are tangential on a chosen non-spherical obstacle. The main focus of this work is on the mathematical details required to apply the high-order algorithm to compute a truncated T-matrix that describes the scattering properties of a chosen perfect conductor in a homogeneous medium. We numerically demonstrate the stability and convergence of the T-matrix computations for various perfect conductors using plane wave incident radiation at several low to medium frequencies and simulation of the associated radar cross of the obstacles. 相似文献