Beneficial Interaction of Coupling and Mismatch in a Two-Antenna System

Multiantenna systems are commonplace in the wireless world. Multiple antennas in a limited volume have coupling among them, which can in many cases be detrimental. However, there are also use cases where the coupling can be a benefit. In this paper, we derive an analytical result to show a benefit of interaction in a two antenna case through weighted feeding, which has been used in the recently proposed antenna cluster concept. The theoretical results are demonstrated with three examples, where different types of two-feed antennas are designed to a mobile phone chassis.