Effect of Antenna Element Placement on Chassis Modes

In this paper, the effect of an actual antenna element location on the chassis modes is investigated. The chassis modes are significantly affected by the presence of the antenna and the amount of effect depends on the structure as well as the location of the antenna on the chassis. The presence of the antenna also creates a new mode that only depends on the geometry of the antenna and is not affected by the location of the antenna on the chassis. In the presence of the antenna, the current maxima of all the modes shift towards the antenna element, that is why pure excitation of single characteristic mode is not possible.