Q-Bandwidth relations for the design of coupled multi-element antennas

A number of interesting approaches for the design of coupled antennas are available [1, 2]. However, with the increasing demand on more compact wireless devices and the urging need for faster design cycles, it is desired to cast the design process in a well defined procedure. This procedure should take into account the governing physical limitations while simultaneously reducing the number of parametric design trials. To this end, this work proposes a systematic approach for the realization of coupled multi-element antennas. Such approach can be adopted easily using either an electromagnetic simulator, or when building antennas on the bench. Not only does the presented analysis define some useful upper bounds on the achievable impedance bandwidth, but it also significantly accelerates the development cycle and alleviates the need for an exhaustive set of parametric trials and optimization cycles.