有限孔径下超指向性平面阵优化设计

Optimization of Superdirective Planar Arrays under a Limited Aperture

摘要:

本文针对有限孔径约束下水听器阵列优化设计问题,研究了四种平面阵列结构：均匀圆阵、五层嵌套圆形阵列、8臂对数螺旋阵列及伞骨架阵列。通过建立各阵列的数学模型,对比分析了不同阵列指向性函数的主瓣宽度、最高旁瓣级等性能参数指标以及各向同性噪声场中最大指向性因子,最后给出了最佳超指向性阵列设计流程。仿真对比结果表明,均匀圆阵具有最窄的水平方向主瓣宽度和最低旁瓣级,但是其俯仰方向主瓣宽度最宽,适用于水下全向目标监视的应用场景；伞骨架阵列具有最窄的俯仰方向主瓣宽度和次低旁瓣级,但是其水平方向主瓣宽度最宽,适用于对空域目标进行广角监视的应用场景。另两种阵列性能介于二者之间。本研究为不同水声探测场景下的阵列选型提供了理论依据与设计参考。

Abstract:

This paper addresses the optimized design of hydrophone arrays under finite-aperture constraints, investigating four planar array configurations: the uniform circular array, five-layer nested circular array, 8-arm logarithmic spiral array, and umbrella skeleton array. By establishing mathematical models for each array configuration, a comparative analysis is performed on key performance parameters of the directivity functions, including mainlobe width and maximum sidelobe level, as well as the maximum directivity factor in isotropic noise fields. Furthermore, an optimized design procedure for superdirective arrays is presented.Simulation results indicate that the uniform circular array achieves the narrowest horizontal mainlobe width and the lowest sidelobe level, while exhibiting the widest elevational mainlobe width, making it suitable for applications such as underwater omnidirectional target surveillance. In contrast, the umbrella skeleton array demonstrates the narrowest elevational mainlobe width and the second-lowest sidelobe level, but with the widest horizontal mainlobe width, rendering it appropriate for wide-angle surveillance of aerial targets. The performance of the other two arrays lies between these two extremes. This study provides a theoretical foundation and design reference for array selection in various underwater acoustic detection scenarios.