Abstract
Multiple-input multiple-output (MIMO) technique is a key technique for communication in the future. It can effectively enhance channel capacity. For future fifth-generation (5G) terminals, it is still a challenging task to realize desirable isolation within a compact size. To achieve an acceptable isolation level, many decoupling methods have been developed. We review the most recent research on decoupling methods, including the employment of external decoupling structures, orthogonal modes, and reduction of ground effect, and discuss the development trends of the MIMO array in 5G smartphones.
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Xiao-xi ZHANG designed the research. Xiao-xi ZHANG wrote the first draft of the manuscript. Ying LIU and Ai-di REN helped organize the manuscript. Xiao-xi ZHANG and Ai-di REN revised and edited the final version.
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Xiao-xi ZHANG, Ai-di REN, and Ying LIU declare that they have no conflict of interest.
Project partially supported by the National Natural Science Foundation of China (Nos. 61871309 and 61971335)
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Zhang, Xx., Ren, Ad. & Liu, Y. Decoupling methods of MIMO antenna arrays for 5G applications: a review. Front Inform Technol Electron Eng 21, 62–71 (2020). https://doi.org/10.1631/FITEE.1900466
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DOI: https://doi.org/10.1631/FITEE.1900466