【作者】 齐飞林；

【导师】 张守宏；

【作者基本信息】 西安电子科技大学 ， 信号与信息处理， 2010， 博士

【摘要】 共形天线阵列不仅具有良好的宽角扫描和空气动力学特性,而且还可以减小雷达散射截面积(RCS)和减小天线/天线罩之间的相互作用,因而在弹载、机载、星载等武器系统中有着广泛的应用前景。毫米波雷达导引头可以采用与其外形相匹配的共形天线阵列代替传统的精密万向伺服跟踪系统,为多模导引头的复合制导提供了实现条件,进而可以改善整个制导系统的性能。将共形阵列技术应用于光电复合制导体制的毫米波导引头,是一种创新型应用概念。本文研究的毫米波共形阵列数字波束形成相关技术,为复合制导体制下共形阵列在毫米波导引头中的应用提供理论和技术支持。本文首先分析了国内外共形阵列最优波束形成理论的研究进展,围绕国防预研项目及国家自然科学基金项目的研究任务,分两部分针对毫米波导引头共形阵列数字波束形成技术进行研究：(1)研究了复合制导体制下的毫米波导引头共形阵列,包括多模孔径复合中的参数设计、共形阵列与平面阵列的性能分析比较、共形阵列对于不同气动外形(几何模型)的波束性能分析与阵列布阵方式、共形阵列的优化布阵方法以及低副瓣波束形成方法；(2)研究了毫米波导引头共形阵列单脉冲和/差波束形成方法。论文内容可概括为如下以下六章：第二章对光电复合制导体制下毫米波导引头中的共形天线阵列技术的若干性能进行了分析。首先,对多模导引头的复合方式进行了分析与讨论；其次,对高速应用场合下毫米波圆锥共形阵列的参数设计进行了研究；然后,推导了共形阵列与平面阵列的天线方向图综合模型,并对扫描时的波束特性进行了分析与比较；最后,对毫米波复合制导体制下圆锥共形阵列的波束扫描区域进行了定量分析,针对毫米波导引头与多模传感器的孔径复合问题,提出了一种基于线性优化二分法的圆锥台共形阵列孔径规划方法。仿真结果表明本文的结构参数设计在高速应用场合下可以得到满足需求的毫米波体制圆锥共形阵列的天线方向图。第三章研究了光电复合制导体制下不同气动外形导引头共形阵列对波束扫描特性的影响,以及不同布阵方式对导引头共形阵列方向图的影响。在对目前世界上各国在役战术导弹进行分析的基础上,构建了几种典型导引头气动外形的结构模型,讨论了适用于共形阵列的不同阵列布阵方式,并建立了任意气动外形下的方向图综合模型。随后针对矩形栅格阵列布阵方式分析比较了不同气动外形导引头共形阵列的波束性能,选择波束扫描性能最优时的气动外形作为研究对象,讨论了不同布阵方式对共形阵列波束特性的影响。仿真和分析表明,在复合制导体制下的矩形栅格阵列布阵方式下,圆锥型导引头共形阵列的波束扫描特性最优；在已知最优气动外形导引头结构的基础上,采用不同布阵方式对导引头共形阵列进行波束形成,矩形栅格阵列布阵方式最优。第四章研究了复合制导体制下毫米波导引头共形阵列的两种优化布阵方法：(1)采用三角栅格阵列布阵方式,提出了一种新的子阵划分方法,开展了基于极化的子阵级自适应处理的布阵方法研究,仿真结果说明利用本文提出的子阵划分方法可以有效抑制由于子阵划分和阵列稀布引起的栅瓣效应,提升导引头共形阵列的子阵级自适应处理性能,极大的减轻自适应处理的运算量；(2)提出了基于最优极化方式的导引头共形阵列稀疏布阵优化设计,仿真结果表明该方法能有效抑制阵列单元稀布而引发的栅瓣效应,极大的降低了阵元分布的密度。第五章研究了复合制导体制下毫米波圆锥型导引头共形阵列的低副瓣波束形成方法。首先,回顾了基于自适应阵列理论的波束形成算法；其次,对极化方式下的交替投影优化方法进行了归纳；然后在实现共形阵列单元极化一致性的前提下,兼顾副瓣电平、阵列增益以及主波束宽度的影响,提出了修正的多目标遗传进化算法；最后根据三种优化方法对毫米波圆锥型导引头共形阵列进行低副瓣波束形成的优化。仿真结果表明在毫米波导引头共形阵列单元实现极化方向一致性的基础上,采用多目标遗传进化算法进行低副瓣波束形成优化,在交叉极化电平、主波束宽度以及阵列增益等性能上其综合性能是最优的。第六章针对传统阵列划分形式的圆锥型导引头共形阵列在偏离视轴方向时无法形成俯仰差波束的问题,研究了阵列结构不满足对称条件的单脉冲测角接收波束(和／差波束)形成。首先从圆锥型导引头共形阵列的结构特性入手,分析了波束指向偏离视轴方向时的圆锥共形阵列的阵元分布情况,构建了入射坐标系和入射参考平面,在此基础上分别提出了基于平面投影方法的共形阵列单脉冲和／差波束形成方法和基于等效源理论的共形阵列单脉冲和／差波束形成方法。仿真结果表明,两种方法均能有效解决在波束指向偏离视轴时的和／差波束形成问题,其中基于等效源理论的和／差波束形成方法具有更好的波束性能,而基于平面投影方法的和／差波束形成方法具有使用灵活、波束形成快速等优点。第七章：对全文工作进行了总结,并对未来的工作进行了展望。更多还原

【Abstract】 The benefits of conformal arrays include reduction of aerodynamic drag, wide angle coverage, reduction of Radar Cross-Section (RCS) and elimination of radome-induced bore-sight error, etc. So conformal arrays will find their potential and promising applications in a variety of fields, ranging from space-borne, airborne, ship-borne, and missile-borne radar, space vehicles and wireless communications to sonar, etc. The antenna conforming to the shape of Millimeter Wave radar seeker surface can substitute the precise universal servo tracking system, have ability of more space and load to install new types of equipment, and then improves the system performance. Conformal arrays in millimeter wave radar seeker with optic/electric compound guidance system is of an innovative concept. This dissertation mainly study the technology about digital beam-forming methods for millimeter wave conformal array, and provide theory and technoligical support for the application of conformal array in millimeter wave compound guidence system.The research development of optimal beam-forming for conformal arrays at home and abroad is analyzed in detail. Then, around research tasks of Advanced Defense Research Programs of China and National Science Foundation of China, the principal study content about digital beamforming methods for millimeter wave radar seeker conformal array of this dissertation is:(1) aperture compound and parameter design in compound guided system, performance analysis and comparison of conformal array and planar array, performance analysis of conformal array seekers with different aerodynamic shape (geometry) and array configuration, optimal array configure method of conformal array, and low sidelobe beam-forming method for conformal arrays; (2) mono-pulse sum/difference beam synthesis method of millimeter wave radar seeker conformal arrays.The main content of this dissertation is summarized as the following chapters:Chapter 2 analyzes some performances of conformal arrays in millimeter wave optic/electric compound guidance system. Firstly, multi-mode seeker compound mode is discussed; secondly, in high speed applications parameter design of millimeter wave conical array is studied; thirdly, conformal array and planar array antenna models are established, and characteristics of scan beam are analyzed and compared; Finally, the quantitative analysis of beam scan region in millimeter wave conical array in compound guided system is studied. For the aperture compound problem of millimeter wave conformal array, based on the dichotomy of linear optimization, the conical array aperture programming method is proposed. Simulation results show that antenna patterns meet the requirements, and the advantages of multi-mode seeker are fully played with the given configuration parameters in high speed applications.In Chapter 3, the beam scanning characteristics of different aerodynamic shape conformal arrays in millimeter wave optic/electric compound guidance system, and array pattern performance of different conformal array configuration are studied. After analyzing the world’s tactical missile in service, several typical aerodynamic seeker conformal array models are constructed, and the conformal array pattern synthesis models of arbitrary shape are established. With regular array configuration beam performance of different aerodynamic shapes is compared. Then the aerodynamic shape of the best performance is selected to analysis the beam performance of different array configuration. Simulation and experimental results show that, with rectangular grid array configuration, the scanning beam performance of conical array is optimal; and the rectangular grid array configuration is optimal in the optimal aerodynamic shape.Chapter 4 developes two optimization methods for array configuration of conformal arrays in millimeter wave optic/electric compound guidence system:(1) With triangular grid array configuration, a new subarray partition method is proposed, and based on subarray adaptive processing considering the polarization, the subarray configuration method is proposed. Simulation results show that the proposed method can effectively suppress the gatelobe caused by the subarray division and sparse array configuration, enhance adaptive subarray processing performance, and greatly reduce the computational burden. (2) Based on the optimal polarization mode, sparse array configuration method of conformal arrays is proposed. Simulation results show that the proposed method can greatly reduce the element density, and effectively suppress the gatelobe caused by the sparse array configuration.Chapter 5 mainly studies low sidelobe beamforming method of conical arrays in millimeter wave optic/electric compound guidence system. Firstly, the traditional plane arrays optimization algorithm based on adaptive array theory is given. Secondly, the alternating projection optimization method considering polarization mode is summarized. Thirdly, after the element polarization of conformal array is adjusted to be consistent, a multi-objective genetic algorithm, considering the sidelobe level, the array gain and the main beam width, is proposed. Lastly, the three optimization methods are used to synthesis low sidelobe pattern of millimeter wave conical array. Simulation results show that after polarization direction of all elements in millimeter wave conformal array achieve consistency, the method based on multi-objective genetic algorithm is have advantages in the cross polarization level, beam width and the array gain.When pointing direction offset the visual axial, conical array is unsymmetrical. In Chapter 6, to synthesize mono-pulse sum and difference beams for Millimeter Wave conical arrays, which the traditional divided method cannot afford, a novel approach based on the equivalence principle is proposed. Firstly, structure characteristics of conformal array are analyzed. Secondly, array element distribution is analyzed, when the beam direction is offset the visual axial. Thirdly, the incident coordinate system and the incident reference plane are constructed respectively. Lastly, the method based on plane projection and the method based on the equivalent principle are proposed to form the mono-pulse sum/difference beam of conformal arrays. Simulation results show that both methods can effectively form the sum/difference beam with the beam direction offset the visual axial, the method based on the equivalent principle can achieve better beam performance, but the method based on the plane projection is more flexible and rapid.Chapter 7 concludes this dissertation and some proposals for future work are also presented.更多还原