High-Performance Air-Filled Multiband Antenna for Seamless Integration Into Smart Surfaces

A highly efficient air-filled multiband antenna is presented for unobtrusive integration into smart surfaces. By introducing a capacitive loading ridge in the cavity formed by two coupled eighth-mode resonators, the higher order modes are judiciously manipulated. A supplementary slot-mode resonance is provided by a resonant U-slot in the first resonator. These measures yield dual-band impedance ma...