“…1 The mutual coupling between antennas is an indispensable factor that cannot be ignored. According to the investigated literature, the existing mainstream decoupling technologies are described as follows: One is to introduce a new coupling current and cancel the original coupling current, such as neutralization line decoupling, 2,3 decoupling network, 4,5 and parasitic element methods. 6,7 the other is to truncate the coupling current.…”