基于仿生原理的电小间距天线阵列超分辨测向方法研究

This research is inspired by a parasitic fruit fly called Ormia ochracea for its remarkable ability of locating the cricket's sound source, and focuses on both the theory and critical technologies for implementing biologically inspired electrically small antenna arrays with super-resolution direction finding. Firstly, a biomimetic circuit model is studied in detail which is incoprated into two receiving antennas for amplifying the phase difference of receiving signals. By combining with the equivalent circuit of electromagnetic coupling between two antennas, we can build a circuit network model for fully describing the two-element biomimetic antenna array. Such a circuit model can be extended to N-port equivalent network model for N-element biomimetic antenna array which can include both the electromagnetic coupling and biomimetic coupling between the array elements. This model is the basis of analysis and design of biomimetic direction finding antenna arrays. Secondly, high resolution direction finding algorithm is stuided and modified by incorporating the special array manifold and steering vector of the proposed biomimetic antenna array. Finally, we will design and fabricate two prototypes of biomimetic electrically small antenna array: one is with two elements and the other is with four or eight circularly distributed elements. The element spacing is chosen as 0.05 or 0.1 wavelengh. The proposed biomimetic arrays are expected to achieve the same or better resolution of direction finding than the ones with traditional element spacing of half wavelength. Their performance will be verified by experimental tests. The proposed idea breaks through the technical bottleneck of poor accuracy of direction finding with electrically small antenna arrays, and will be a significant complement to the existing direction finding methods. This project deserves more research and the achievement will be very significant for both civil and military applicatons.

受Ormia ochracea寄生蝇优异的超分辨声源定位能力的启发，本项目研究在电小间距天线阵列上实现超分辨高精度仿生测向的机理及其实现的方法。首先，深入研究增强两天线感应信号相位差的仿生耦合电路，结合电小间距阵元电磁耦合等效电路，建立双天线电磁耦合-仿生耦合电路模型，并在此基础上发展圆环阵列超分辨测向的多端口电磁耦合-仿生耦合电路网络模型。该电路等效模型是分析和设计仿生测向阵列的主要依据。其次，研究仿生测向天线的阵列结构和导向矢量特性，修正原有的高分辨测向算法。最后，结合电磁耦合、仿生耦合模型及测向算法的研究，在电小间距（0.05～0.1 个波长）的双天线及圆环阵列上达到或超过相应半波长间距阵列的测向精度，实现超分辨测向性能。该项目研究有望突破电小间距天线阵列高精度测向的技术瓶颈，丰富和拓展目前无源电磁测向的方法，具有重要的学术研究价值，且成果在军用及民用领域均具有广泛的应用价值。

受Ormia ochracea 寄生蝇优异的超分辨声源定位能力的启发，本项目研究在电小间距天线阵列上实现超分辨高精度测向的原理及其实现方法。分析了Ormia 机械耦合的超分辨无源测向的机理，研究了电小间距双天线（间距为0.1波长及0.02波长）测向的电路耦合模型，并提出了测量这种耦合机制对测向精度改善的新定义。分析了电磁耦合对电小间距双天线以及电小间距四单元圆环天线测向的影响，完成考虑耦合的电小间距阵列高分辨测向算法的修正和优化。推导了强电磁耦合情况下电小间距阵列测向估计误差的克莱美边界。提出了多种改进电小间距阵列测向分辨率的方法，包括加载高磁材料、加载人工超材料、以及一种新颖的振子互连的电小间距双端口及四端口测向阵列结构。对振子互连结构的电小间距双端口及四端口测向阵列进行了实验验证，结果证明了电小间距阵列实现高精度测向的可行性。上述研究成果初步证明了电小尺寸天线阵列上实现高精度测向的可行性，并提供了重要的研究思路，丰富和拓展了目前无源电磁测向的方法，在军用及民用领域均具有重要的应用价值。