Characteristic Modes: Progress, overview, and emerging topics

Over the past decade, characteristic mode analysis (CMA) research has grown from a niche topic to a mainstream topic, warranting a tutorial-style special issue to survey the significant progress that has been made in this field. In this introductory article, the focus is on providing the big picture. We start with a simple description of characteristic modes (CMs). Next, we examine the trends in this field and provide further insights into CMA’s historical development. We will also address common myths surrounding the subject. Then, leaving the detailed coverage of major topics to several other articles, we summarize recent applications of CMA in scattering and other emerging topics. Finally, we conclude with some future perspectives on this field.