基于ISAR 成像和散射中心提取的目标RCS 近场测量方法

Near-field Measurement of Target RCS Based on ISAR Imaging and Scattering Center Extraction

中文关键词:  雷达散射截面积  二维ISAR 成像  近场测量  探头补偿  CLEAN 算法

英文关键词:radar scattering cross section  2D ISAR imaging  near-field measurement  probe compensation  CLEAN algorithm

中文摘要:

      本研究通过结合逆合成孔径雷达(ISAR)成像和散射中心提取技术,实现了近场测试距离下目标雷达散射截面积(RCS)的有效测量。利用近场球面波修正技术和探头补偿技术减少了近场球面波效应和收发探头对成像质量的影响。对ISAR 目标图像采用散射中心提取技术,消除了ISAR 目标图像中由于带宽有限所导致的旁瓣效应。文中针对散射中心提取中截断阈值的选取准则进行了深入研究,给出了截断阈值判定的经验公式并结合仿真实验进行了验证。最终利用标准球锥散射体的暗室近场测量数据对文中所提出的方法进行了实测验证,并与多层快速多极子(MLFMA)方法仿真结果 吻合良好,验证了文中方法的有效性。

英文摘要:

      In this paper, the effective measurement of the target radar scattering cross section (RCS) area at the near-field test distance is achieved by combining inverse synthetic aperture radar ( ISAR) imaging and scattering center extraction techniques.The near-field spherical wave correction technique and probe compensation technique are used to reduce the effect of near-field spherical wave effect and transceiver probe on the imaging quality. The scattering center extraction technique is applied to the target ISAR image to eliminate the side-lobe effect caused by the limited bandwidth in the target ISAR image and to reduce the data storage requirement. The selection criterion of the truncation threshold in the scattering center extraction is studied in depth, and the empirical formula for the determination of the truncation threshold is given and validated with simulation experiments. Finally, the chamber near-field measurements of standard spherical cone scatterers were used to validate the method studied in this paper, and the results agreed well with the multilayer fast multipole simulations, which verified the effectiveness of the proposed method.