Metamaterial‐based frequency reconfigurable antenna

A frequency reconfigurable antenna based on metamaterial is presented. It is composed of a coplanar‐fed straight‐line monopole with two double split‐ring resonators (DSRRs) of different size disposed at its proximity. Each cell exhibits a negative permeability over a frequency band, which produces magnetic couplings with the monopole that starts to radiate at new bands; the whole structure is now a tri‐band antenna. The frequencies over which the two DSRRs exhibit a negative permeability have been arbitrarily chosen to show that the proposed approach can be used to create new operating bands and also to introduce notches. By using a single switch at each metamaterial cell, their effect can be deactivated and the corresponding resonance can be suppressed, resulting in a frequency reconfigurable antenna. Simulated and measured results are presented and good agreement is achieved.