发表机构
Interuniversitair Micro Electronica Centrum; Katholieke Universiteit Leuven（微电子研究中心; 鲁汶天主教大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文分析并近似稀疏天线阵列的空间宽带阵列因子，提出卷积表示和解析公式，证明旁瓣随带宽-孔径乘积增大而有效抑制。
AI 中文摘要
本工作研究了线性稀疏天线阵列的空间宽带（SWB）阵列因子（AF）。SWB AF被表述为匹配滤波器，并表示为空间窄带（SNB）AF与SWB核的空间变卷积。最初针对均匀阵列推导的SWB AF近似被重新审视并扩展到稀疏阵列。该近似在广泛的参数范围内被证明保持准确。将SWB AF表示为卷积提供了对带宽-孔径乘积如何修改SNB AF的直观解释。具体而言，SWB核充当SNB AF的 averaging 窗口，抑制SNB AF的旁瓣电平（SL）。在稀疏阵列中，远离主瓣的旁瓣可视为随机的、类似噪声的，使得平均和抑制特别有效。接下来，首先引入SNB稀疏阵列中期望SL和峰值旁瓣电平（PSL）的解析公式，随后将其扩展到SWB体制。最后，提供了具有均匀频谱的均匀稀疏阵列的期望SL和PSL电平的简单闭式表达式。期望的SWB SL和PSL被表述为带宽-孔径乘积的函数，并显示随距主瓣距离的增加而稳步下降。
英文摘要
This work investigates the spatially wideband (SWB) array factor (AF) of linear thinned antenna arrays. The SWB AF is formulated as a matched filter and expressed as a spatially variant convolution of a spatially narrowband (SNB) AF and a SWB kernel. Originally derived for uniform arrays, the SWB AF approximation is revisited and extended to thinned arrays. The approximation is shown to remain accurate across a wide range of parameters. Representing the SWB AF as a convolution offers an intuitive interpretation of how the bandwidth-aperture product modifies the SNB AF. Specifically, the SWB kernel acts as an averaging window for the SNB AF, suppressing the sidelobe levels (SL) of the SNB AF. In thinned arrays, the sidelobes away from the mainlobe can be treated as random, noise-like, making averaging and suppression particularly effective. Next, the analytical formulas for the expected SL and peak-to-sidelobe level (PSL) in SNB thinned arrays are first introduced and subsequently extended to the SWB regime. Finally, simple closed-form expressions for the expected SL and PSL levels of the uniformly thinned arrays with a uniform spectrum are provided. The expected SWB SL and PSL are formulated as functions of the bandwidth-aperture product and are shown to steadily decrease with distance from the mainlobe.
