Ultra-robust air-filled multiband antenna for smart surface integration

A low-cost and highly efficient multiband antenna, operating in the SRD860 (863–870 MHz), 2.4-GHz ISM (2.4–2.4835 GHz) and LTE-7 (2.5–2.69 GHz) frequency standards, is proposed for deployment in smart surfaces. It exploits the electromagnetic shielding of a ridged air-filled cavity with completely metallized sidewalls, to enable extensive integration opportunities. Measurements demonstrate the excellent antenna robustness in several integration scenarios, indicating a great compatibility with a wide range of superstrates, as well as a strong isolation from supporting and surrounding materials.