A High Gain Zero Index Metamaterial for Radome Applications

Antennas in radar systems are protected on the outside by dielectric materials called radomes. Radomes are prone to boresight error and loss of electromagnetic energy. Metamaterials can be used in enhancing the performance of radome by eliminating boresight error and alleviating loss of energy. This paper proposes a compact single layer radome made up of an S-shaped zero-index metamaterial that operates at X-band frequency i.e., 10 GHz. A radome is designed by the periodic repetition of 10 x 7 S-ring unit cells. Radome is realized on Rogers RT/Duriod 5870 substrate (having permittivity ɛr = 2.33) with dimensions of 35 mm x 35mm x 0.5mm. The proposed design provides an overall gain of 9.8dB (18% more than antenna), eliminates the boresight error and has a wider band of operation from 9 to 11 GHz.