Conventional multiband antennas suffer from strong interactions among different operating frequencies, complex configurations, low bandwidth, and reduced efficiencies. A design concept for a multibeam multiband antenna in wireless devices is proposed in this paper. The design concept provides a promising approach to augment transmission and reception. The principle of design involves a primary radiating element embedded in a triplate conformation which excites a passive array of multiple frequency secondary radiators, forming a frequency selective structure in triplate (FSST). The higher order mode behavior of the parent antenna characterizes the design of FSST placed in its nearfield. The mathematical modeling and analysis of the design methodology is also presented. As proof of concept, the proposed design methodology is validated with simulations and experiments at four unlicensed communication bands and the results are compared.

中文翻译：

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基于FSS的无线设备三板天线设计理念

传统的多频带天线在不同的工作频率、复杂的配置、低带宽和降低的效率之间存在强相互作用。本文提出了一种无线设备中多波束多频带天线的设计理念。该设计概念为增强传输和接收提供了一种有前途的方法。设计原理涉及嵌入三板构造的初级辐射元件，它激发多频次级辐射器的无源阵列，形成三板（FSST）的频率选择结构。父天线的高阶模式行为表征了放置在其近场中的 FSST 的设计。还介绍了设计方法的数学建模和分析。作为概念证明，