【作者】 张鹏；

【导师】 杨鹏；

【作者基本信息】 电子科技大学 ， 电子科学与技术， 2024， 硕士

【摘要】 凭借着快速波束扫描和灵活的波束赋形能力,相控阵天线成为现代军事和民用行业不可或缺的关键技术,但其成本高昂和结构冗杂等缺点严重限制了传统相控阵天线在毫米波频段的广泛应用。因此,将辐射与低相位量化移相结合的数字比特阵列应运而生。数字比特阵列是通过加载可控集总元件构建可编程的数字化天线结构,从而对空间电磁波特性进行实时调控。因无需TR组件即可实现波束扫描和空间功率合成,所以强制馈电的数字比特阵列具有低成本、低剖面和易与载体平台集成等优点。本文探讨了Ka波段强制馈电数字比特阵列的设计原理,验证了毫米波低成本相控阵方案的实现方法,具体研究内容如下:设计了一款基于级联移相的Ka波段稀布阵列样机,该样机利用粒子群算法和遗传算法优化出最小间距约束的稀布子阵布局,并将该六边形子阵旋转拼接为64阵元的稀布阵列,以此解决阵元间距扩大引起的副瓣电平抬升等问题。得益于小型化天线单元的双线极化可重构和2比特相位量化特性,该阵列的实物样机可以在Ka波段实现两种极化下±60°范围内良好的二维空间波束扫描,其最高增益达到18.5 d Bi。与同口径半波长均匀阵列相比其法向增益损失在1 d B以内,角度分辨率损失小于20%。设计了一款Ka波段有源数字比特阵列,该天线将集成了4个PIN二极管的2比特小型化天线单元组成2×4规模的一维阵列,并构建了加载有源器件的8层PCB叠层设计方案。实测结果显示,该阵列可在一维空间内实现±58°的实时波束扫描,且在58°方向处其扫描增益损失仅为3.3 d B,副瓣电平为-3.6 d B。该阵列可在Ka波段实现最高41 d Bm的饱和EIRP,以此证明其空间大功率合成的能力。该阵列为毫米波低成本有源相控阵的设计提供了可行的解决方案。更多还原

【Abstract】 With its fast beam scanning and flexible beamforming ability,phased-array antenna has become an indispensable key technology in modern military and civilian industries.However,its high cost and complex structure seriously limit the widespread application of traditional phased-array antenna in the millimeter wave band.Therefore,digital bit array that combines radiation and low quantization phase shift has emerged.Digital bit array is a programmable digital antenna structure constructed by loading controllable lumped elements,so as to real-timely control the characteristics of spatial electromagnetic wave.Due to its beam scanning and spatial power synthesis can be achieved without TR module,directly fed digital bit array has advantages such as low cost,low profile,and easy integration with carrier platforms.This article discusses the design principle of Kaband directly fed digital bit array,and verifies the implementation method of millimeterwave low-cost phased-array scheme.The specific research contents are as follows:A Ka-band sparse array prototype based on cascaded phase shift is designed.The prototype uses particle swarm optimization and genetic algorithm to optimize the layout of the sparse subarray with minimum spacing constraints.The hexagonal subarray is rotated and spliced into a sparse array of 64 elements to solve the problem of sidelobe level rise caused by the expansion of array element spacing.Thanks to the dual line polarization reconfigurability and 2-bit phase quantization characteristics of the miniaturized antenna unit,the physical prototype of this array can achieve good twodimensional spatial beam scanning in ±60° range of two polarizations in the Ka-band,with a maximum gain of 18.5 d Bi.Compared with the same aperture half-wavelength uniform array,its loss of normal gain is less than 1 d B and the resolution loss at each scanning angle is less than 20%.A Ka-band active digital bit array is designed,which integrates a 2-bit miniaturized antenna unit with four PIN diodes to form a 2×4 scale one-dimensional array.An 8-layer PCB laminated design scheme was constructed to load active devices.The measured results show that the array can achieve real-time beam scanning of ±58° in onedimensional space,and the scanning gain loss at the 58° direction is only 3.3 d B,with the sidelobe level of-3.6 d B.The array can achieve the saturated EIRP of up to 41 d Bm in Ka-band,demonstrating its capability of spatial high-power synthesis.This work provides a feasible solution for the design of low-cost active phased-array antenna in the millimeter wave band.更多还原