基于正交惠更斯源的极化相控阵雷达阵元设计与极化测量方法研究

The design and development of polarimetric phased array radar is a challenge problem in current radar community. There is an inherent technical difficulty for planer polarimetric phased array radar system consisted of common dual-polarized elements. When beams steering away from array broadside,the radiate fields of two polarized electric fields are not orthogonal, and there will be cross couplings between signals of two polarizd channel which can cause errors in polarimetric parameters measurement.In order to reslove this problem, a innovative theoretic model of polarimetric phased array antenna consisted of orthonogal Huygens sources elements is proposed in this project, and the orthogonality of two polarized radiate fields is assured. In order to resolve the problem of accurate polarimetric parameters measurement in phased array radar, three aspects of researches will be carried out in this project with the help of proposed model. Firstly, the methods of designing and developing practical dual-polarized orthogonal Huygens sources antennas will be investigated in this project. Secondly, polarimetric parameters measurement methods in different polarimetric measurement modes will be investigated based on the new polarization basis induced by orthogonal Huygens soureces. Thirdly, the errors of polarimetric parameters measurement casued by the non-ideality of element's polarized characteristics and mutual coupling effects will be investigated in this project, and the calibration technology of polarimetric phased array radar will be addressed.

研制具有精确极化测量能力的相控阵雷达，是当前雷达研究领域的一项挑战性课题。以传统双极化天线为阵元的平面相控阵雷达系统，存在一个固有的技术难题：当电扫波束指向偏离阵面法线方向时，天线主波束内两种极化的辐射电场将不再具有正交性，这会引起两个极化通道信号在空间中交叉耦合，从而导致极化测量存在较大的误差。本项目创新性地提出了一种以正交惠更斯源为阵元的极化相控阵天线方案，可保证两种极化的辐射场在任意波束指向上的空间正交性，从而在理论上解决了这一难题。以此为基础，面向气象探测等领域的应用需求，围绕相控阵雷达极化参数精确测量问题，本项目将开展以下研究：①研究正交惠更斯源这一特殊形式双极化阵元的设计方法和工程实现方案；②基于正交惠更斯源所引入的新极化基，研究不同极化测量体制下的极化参数测量方法；③分析由实际天线阵元极化非理想性和阵元互耦效应所引入的极化测量误差，研究相控阵体制雷达极化测量误差校准技术。

目标极化信息的获取精度直接制约着极化信息的处理能力和应用效果。具有精密极化测量能力的相控阵雷达因其快速的波束扫描和灵活的信号处理等能力将在未来的气象观测、空中监视、防空反导等领域中全面提升雷达的检测、跟踪、测量、成像、识别以及抗干扰等性能。相控阵雷达天线极化特性随波束扫描角度改变而变化这一规律将对精密极化测量产生严重影响，是亟待解决的瓶颈问题。本项目针对这一问题，以基于正交惠更斯源阵元模型的极化相控阵雷达极化测量方案为基础，在极化相控阵天线空域极化特性分析与建模、极化相控阵天线阵元与阵列设计、极化相控阵天线波束形成技术、极化相控阵雷达目标参数估计方法、极化相控阵雷达测量误差校正技术等方面进行了深入研究，攻克了相关的关键技术问题，达到了预期研究目标，为新一代极化相控阵雷达系统的研制提供了理论、技术和应用支撑。