Dual-band/dual-mode ε negative resonance antenna

In this paper a dual-band resonance antenna based on the ε negative (ENG) transmission line (TL) resonator is presented. This antenna has two unit cells and implemented using the mushroom like structures in which two notches are cut from edges. The operational frequencies of this antenna correspond to the zeroth and first resonance frequencies of the ENG TL resonator. By variation of the length of the notches, various frequency ratios can be obtained. The presented antenna has a monopolar radiation pattern at the first frequency and broadside radiation pattern at the second frequency. Hence this is a dual-mode antenna which has two different radiation mechanisms at its operational frequencies.