Ultra-wideband antenna with switchable band-notched behaviour

Capacitive Coupling Element Antennas for Multi-Standard Mobile Handsets

“…Equivalent circuit modeling and theory of characteristic modes (TCM) have been used to analyze the chassis-antenna coupling of the CCE and various other antennas [4], [13], [14], and consequently, to optimize the coupling, e.g., by choosing the best location for the antenna excitation or by modifying the ground plane [15], [16]. Also the shape of the feeding strip/plate affects the potential performance of an antenna [16]- [18], regardless of the type of the antenna.…”

Analysis and design of antennas for wireless communications using modal methods

“…From the current distribution of these modes in the two structures, it is possible to deduce that this is caused by the optimal location of the slot in a position within the structure, where the current is not significantly altered. The height of the slot, measured from the ground plane, is critical to avoid disturbing the current distribution of modes J 1 and J 3 excessively [131]. These modes present a very intense current at the base of the monopole, whose value decreases sharply as it flows away.…”

“…Therefore, the antenna filtering capability can be further improved by making this band-notched behaviour switchable [131] [132]. Since the existence of interfering systems depends on the antenna environment, the filtering function exhibited by planar monopoles with fixed band-notched behaviour might not be necessary in some cases.…”