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TOPS-SAR通过波束快速扫描可以极大地提高SAR的测绘效率,然而传统TOPS-SAR模式波束只在雷达一侧扫描,为了进一步提高SAR的测绘效率,本文提出了一种改进的TOPS模式,即双侧TOPS-SAR模式。在该模式下,雷达左右两侧分时快速扫描,可以克服传统扫描模式只能一侧成像的缺陷。针对该新模式,提出了一种基于子孔径的成像处理方法,该方法通过子孔径成像并进行图像拼接,实现天线波束扫描与成像同时进行。仿真和实测数据处理结果验证了该算法的有效性。 相似文献
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邱德厚 《太赫兹科学与电子信息学报》2019,17(5):845-849
提出一种实波束扫描雷达前视成像回波建模方法。使用实波束扫描实现雷达平台正前视区域二维高分辨成像。根据雷达波束掠过成像扇区的时间先后关系,将成像扇区方位向回波数据表征为天线主瓣波束采样序列与目标反射率分布函数沿成像扇区方位向采样序列之间卷积的形式。最后,通过仿真数据验证了本建模方法的有效性。 相似文献
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介绍了一种双波束相控阵天线,阐述了其工作原理、设计方法及实测结果。该天线阵工作于P波段,用于雷达干扰发射系统,发射波束为方位同时双波束,并且每个波束均可独立电扫描,实现了同时对多目标、多方位的雷达干扰。 相似文献
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相控阵雷达由于其波束扫描的快速性和稳定性、波束控制的灵活性、易实现多波束探测和跟踪、易实现波束锐化
等优点,已广泛应用于地面雷达,也是弹载雷达的一个重要发展方向。作者研制的数控移相收发组件实现了将射频移相
转至中频移相实现,具有低成本、体积小、相位变化灵活的特点。 相似文献
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某些低空目标指示雷达中,在方位上机械扫描的同时,俯仰上采用时序波束电扫的方法,实现三坐标测量,因其造价低,而被广泛使用.由于这种雷达俯仰面波束的时序扫描而产生低波位的强地物回波处理剩余,作为地物杂波在高波位时跨周期出现,影响雷达系统正常的检测与显示,为解决此问题文中提出了一种比较有效的处理方法. 相似文献
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天线方向图是天线辐射特性的重要参数,大型电扫相控阵雷达的天线方向图往往难以准确测量。扫描方向图是利用电扫相控阵波束捷变的特点形成的方向图,较为准确地表征了天线的辐射特性,是对天线方向图很好地近似。文中结合多个大型雷达的工程研制经验论述了在远场和中场测试天线方向图的方法,提高了测试效率和精度,得到了令人满意的结果。 相似文献
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相频扫天线阵系统研制报告 总被引:1,自引:0,他引:1
一、概况相频扫天线阵系统专题研究是兵器工业部于一九七九年正式下达的部重点专题研究项目。它是为研制新型炮位侦察校射雷达而设置的,它的研制成果将是该雷达整机研制的重要基础。该雷达能电控天线波束快速扫描以处理多个目标,并能测出炮弹一段轨迹,通过外推确定敌方炮位,达侦察之目的;或确定我方炮弹落点,达校射之目的。因此要求天线波束能在±45°范围内快速扫描,在俯仰面小角度扫描,并且具有较高的波束指向精度。为使雷达体积小重量轻、结构紧凑而选择了 X 波段。 相似文献
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JY-21全固态航管一次监视雷达是按中国民航空中交通管制(ATC)需求研制的新一代机场监视雷达(ASR)。该雷达集飞机监视和气象探测于一体.具有独立的气象信息通道.可以自动提取飞机的点迹数据和气象的反射率数据.整机在不失性能先进的前提下.突出了可靠性、维修性设计.具有较好的联机维修特性。本文叙述了JY-21雷达的技术特点和设计原理。 相似文献
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本文回顾和梳理了当前片上雷达(Radar on Chip, RoC)的架构和射频前端、天线及信号处理等芯片化研究进展,以及基于异质异构集成、3D先进封装技术的雷达系统集成实现方案。在此基础上,从物理形态、实现工艺及技术发展等方面对片上雷达未来发展趋势进行了分析,指出基于硅基半导体工艺,片上集成多路雷达收发前端、波形产生及信号处理等雷达功能单元,实现片上系统(System on Chip, SoC);或者通过异质异构及先进封装技术,将高度集成的雷达芯片集成在一个封装内,实现封装系统(System in Package, SiP),从而满足雷达系统微型化、轻重量、低成本和低功耗的发展需求。同时,基于芯片化可扩充多通道阵列模块也有望构建大型复杂阵列雷达系统。该方案为未来小型化武器装备提供有效的探测感知手段,也为蓬勃发展的民用雷达提供可行的技术路径。 相似文献
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舰载雷达的工作环境海杂波多,导致雷达在跟踪时可能关联上杂波。针对这个特点,本文应用最近邻联合概率数据关联(NJPDA)算法作为舰载雷达目标跟踪的数据关联算法,这个算法可以解决密集目标的正确跟踪问题。仿真结果理想,仿真场景设为目标相交、目标平行、有杂波时均可正确跟踪。 相似文献
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主要介绍利用MATLAB软件的GUI功能构造雷达伺服系统仿真软件包,举例说明驱动功率计算,误差估计,可靠性估算的计算机辅助分析和设计,利用本文设计的软件工具包可以简单方便地估算伺服系统的基本性能,用以指导实际系统设计。 相似文献
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SAR Images of Rooms and Buildings Based on FDTD Computer Models 总被引:1,自引:0,他引:1
This paper presents synthetic aperture radar (SAR) images of rooms and buildings based on numerical simulations, with application to sensing through the wall (STTW) scenarios. We use the finite-difference time-domain modeling technique to compute the radar return from configurations of increasing complexity, where humans and furniture objects are placed in a room. We apply SAR image formation techniques and analyze the images obtained for various wall materials, aspect angles, and radar parameters. We investigate the multipath propagation issues relevant to STTW imaging radar and discuss the radar parameter tradeoff based on image quality. We also look at images obtained in cross-polarization, demonstrating how this radar operational mode can achieve significant clutter rejection. The phenomenological results obtained in this paper can be used as guidance by radar engineers in order to optimize the performance of STTW SAR imaging systems. 相似文献
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In the traditional transmitting beamforming radar system, the transmitting antennas send coherent waveforms which form a highly focused beam. In the multiple-input multiple-output (MIMO) radar system, the transmitter sends noncoherent (possibly orthogonal) broad (possibly omnidirectional) waveforms. These waveforms can be extracted at the receiver by a matched filterbank. The extracted signals can be used to obtain more diversity or to improve the spatial resolution for clutter. This paper focuses on space-time adaptive processing (STAP) for MIMO radar systems which improves the spatial resolution for clutter. With a slight modification, STAP methods developed originally for the single-input multiple-output (SIMO) radar (conventional radar) can also be used in MIMO radar. However, in the MIMO radar, the rank of the jammer-and-clutter subspace becomes very large, especially the jammer subspace. It affects both the complexity and the convergence of the STAP algorithm. In this paper, the clutter space and its rank in the MIMO radar are explored. By using the geometry of the problem rather than data, the clutter subspace can be represented using prolate spheroidal wave functions (PSWF). A new STAP algorithm is also proposed. It computes the clutter space using the PSWF and utilizes the block-diagonal property of the jammer covariance matrix. Because of fully utilizing the geometry and the structure of the covariance matrix, the method has very good SINR performance and low computational complexity. 相似文献
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Wideband radar imaging with range gating and high sensitivity can be achieved with the use of low-cost commercially available narrowband IF filters. Such filters reduce the effective receiver noise bandwidth of the radar system. This allows for high sensitivity, comparable to that of single-sideband radio receivers, while at the same time acquiring de-chirped wide-band received waveforms. A carefully developed radar architecture, based on the use of these IF filters, is shown in this paper. This radar architecture is then implemented in an X-band linear rail synthetic-aperture-radar (SAR) imaging system. The X- band rail SAR is a linear FM-chirped radar, which chirps from approximately 7.5 GHz to 12.5 GHz. The radar front end is mounted onto an eight-foot-long linear rail. The transmitted power is adjustable to 10dBm or less. It will be shown that objects as small as groups of pushpins in free space can be imaged using transmitted power as low as 10 nW. These results are compared to previous direct-conversion X-band FMCW rail SAR work. A high-sensitivity X-band rail SAR such as this could be useful for measuring low-radar-cross-section (RCS) targets. This radar could be used in high clutter environments that require a range gate. This low-power X-band rail SAR could be useful for operation in restricted transmission areas, where maximum radiated power is severely limited. Other applications include any that require low transmitter power, such as automotive radar. 相似文献