fourth‐generation mobile wireless communication networks, the focus of most antenna researchers was largely on antennas for radar and satellite communications. On the other hand, antenna designers working in the mobile communication industry were faced with “engineering” challenges largely ignored by the majority of academic antenna researchers. The collocation and coexistence of antennas for 3G and 4G, as well as the demand for antenna miniaturization and stringent specifications, posed serious research challenges to the antenna community. However, judging by the number of publications, one may argue that base station antennas and terminal antennas did not receive the attention they deserved from academic researchers. This lack of attention might have been partly attributed to the unique global industrial landscape formed in that period; the industry was consolidated to only a few players in the end. Moving forward to 5G and 6G, the technology competition among national governments and industries from all around the globe is rapidly gathering pace, thus attracting the widespread interest of the international antennas community. As a result, research on 5G and 6G antennas has started taking center stage globally. In this chapter, we have provided our own perspectives for 5G and 6G antennas. We have outlined some of the major challenges facing antenna researchers and designers, and have enunciated possible technology pathways. In the following chapters, we shall present detailed overviews, and our own studies to address some of the main technical challenges associated with 5G and beyond antenna arrays. We have mainly focused on antennas for base stations and large platforms. Given the potentially vast scope of 5G and 6G systems, we make no claim that all the antenna topics for 5G and beyond have been covered.
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