共查询到20条相似文献,搜索用时 203 毫秒
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文中提出一种基于角反射器的箔条雷达散射特性增强方法,旨在通过增强单根箔条的散射特性,利用有限数量的箔条实现海量箔条云团的雷达散射截面积(radar cross section,RCS).在传统"偶极子"箔条的基础上,利用圆板角反射器结构的强散射特性来增强箔条的电磁散射.同时,为了兼顾各个方向上的电磁散射,利用多个圆形角反射器拼接成为外轮廓为球形的强散射结构,通过调节球形结构的半径,可以实现对单个箔条和箔条阵列RCS的控制.最后,将单个箔条组成阵列,形成新型箔条结构.对工作频率、入射角度、球形包络半径等不同参数下基于角反射器散射增强的箔条雷达散射特性进行了仿真分析,结果表明利用新型箔条散射增强结构,能使单根箔条的RCS增大30 dBm2以上. 相似文献
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针对传统角反射器的性能强烈依赖于入射波长,难以对抗变频雷达探测的问题,设计了一种加载超材料吸波体的新型三面角反射器。在8 GHz与12 GHz两个频点,产生近似相同的后向雷达散射截面(RCS)。对该角反射器的性能进行测试验证。结果表明:加载超材料吸波体后,在12 GHz频点,其RCS值下降约3.6 dBsm,在8 GHz频点,其RCS值与普通角反射器相比,下降约0.1 dBsm。新型角反射器的性能满足设计要求,为有效对抗变频雷达对角反射器假目标的探测与识别提供了新的途径。 相似文献
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太赫兹雷达散射特性的研究对于目标识别、跟踪以及截获有重要意义.设计了0.22 THz频率步进雷达散射截面(Radar Cross section,RCS)测量系统,提出了针对频率步进太赫兹雷达信号体制下,角反射器RCS的提取方法.采用实验与仿真相结合的方式,得到了单个角反射器和角反射器组在4°范围内的太赫兹雷达散射截面.结果表明,角反射器类目标的RCS实验测量结果与理论计算结果在误差范围内一致性较好,为进一步精确测量目标在太赫兹波段的散射特性奠定了研究基础. 相似文献
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微变监测雷达能够对观测区域进行全天时、全天候、非接触式、大面积、亚毫米级精度的形变位移监测,其监测精度分析是进行形变分析和精确预警的关键科学问题。本文采用便携式全方位微变监测雷达系统进行了精度研究和测试分析,首先推导了便携式全方位微变监测雷达的一维和二维信号模型,并对影响微变监测雷达监测精度的因素进行了分析;其次,设计一维形变监测实验,采用角反射器等强反射体作为观测目标,并将光学棱镜与角反射器刚性连接,通过雷达监测结果与全站仪监测结果的对比,对一维形变监测精度进行分析;最后,以分布式角反射器模拟观测场景,分析微变监测雷达的二维形变监测精度。一维、二维形变监测实验结果表明,监测结果与实际位移一致性较好,设计的参考角反测量均值在0.1mm之内,且系统形变监测精度可达亚毫米级,能够实现高精度的微变形监测应用。 相似文献
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介绍了海上电子战中的雷达无源干扰技术。说明了雷达干扰的任务和种类;并且阐述了无源干扰的含意和特点。论述了无源干扰中最常用的箔条的用途、技术指标及其在海上雷达对抗中的应用实例。此外还介绍了角反射器和龙伯透镜反射器在海上雷达干扰中的使用方法。 相似文献
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An experimental investigation of a novel corner reflector antenna with improved performance is reported. The corner reflector antenna has been structurally modified by attaching two more reflector elements. The parameters such as the primary corner angle, position, width and angle of the secondary elements have significant effects on the H-plane radiation characteristics of the antenna. Certain symmetric configurations of this triple corner reflector (TCR) antenna provide sharp beams with a gain of the order of 3 dB over that of the conventional corner reflector (CR) antenna 相似文献
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二面角是众多雷达目标中的典型散射结构,是典型的二次散射体,其特征识别对于复杂目标的识别具有重要意义。首先在频域内应用PO光学计算方法得到二面角的散射信号,通过IFT变换得到时域散射信号。采用幅度调制信号与目标的时域散射信号进行卷积,即得到目标的距离像。一维距离像是二维合成孔径成像的基础。 相似文献
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E. Sauter G. V. Schultz R. Wohlleben 《Journal of Infrared, Millimeter and Terahertz Waves》1984,5(4):451-463
To verify the enhancement in sensitivity of a Schottky barrier diode using a 90° corner reflector at submillimeter wavelength a 65∶1 scaled model of the open structure mixer was constructed and investigated at 2.8 cm wavelength. The results show clearly the advantage of a 90° corner reflector, the reality of the deviations for 45° and 60° corner reflectors found for submillimeter wavelengths, and the equality of the antenna patterns for a 90° corner reflector and a “cat-eye” (corner cube) reflector. 相似文献
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B.B. Jian 《Photonics Technology Letters, IEEE》1996,8(12):1609-1611
The effect of the corner reflector size on the performance of an etched corner reflector array laser is studied. Experimental evidence is presented to show that the operation of the corner reflector array laser is governed by the diffraction principle. The light output increases markedly if the reflector size is large enough so that diffraction can be neglected. This general principle should prove useful in the design of unguided photonic integrated circuits. 相似文献
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Two reflector antennas are proposed. The first is constructed by adding a cylindrical reflecting surface of suitable radius to theV -shaped corner reflector antenna. The feeding element is a half-wavelength dipole. The resulting cylindrical corner reflector provided a 2 dB increase in gain, minimum sidelobe level, low input reactance, and uncritical dependence of performance on frequency. The second antenna is constructed by adding a cylindrical surface to the three-dimensional corner reflector. This extension provided an increase in gain of at least 6.5 dB, an input resistance compatible with the commercially available 50- or75-Omega coaxial cables, low input reactance, and uncritical dependence of performance on frequency. A grid-type cylindrical corner reflector antenna, and a three-dimensional corner reflector antenna with a cylindrical subsurface of finite reflecting surfaces were designed, and the measured input impedances, gains, and field patterns showed excellent agreement with the theoretical results for both antennas. 相似文献
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A cluster reflector formed by a perfect electric conductor coated trihedral corner reflector, and soft and hard surface coated triangular trihedral corner reflectors, can be used in marine/air navigation. The cluster reflector scatters back circularly polarised waves of one or the other bandedness depending on which reflector is illuminated 相似文献
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飞行器翼身接合部构成的二面角反射器是很强的电磁散射源。但是传统的计算方法仅仅适用于理想二面角反射器。该文采用几何光学法和物理光学法分析矩形二面角反射器的多次反射,在照明宽度概念的基础上,提出了等效照明面积的概念。通过对等效照明面积的分析,给出了能计算任意平面形状、有遮挡效应的二面角反射器后向雷达散射截面的工程方法。通过对某高超声速飞行器翼身结合段雷达散射截面的计算,验证了该方法的正确性。 相似文献