Design of Metamaterial Inspired Miniaturized Microstrip Antennas Based on Zero Order Resonators

Metamaterial inspired zero order resonator (ZOR) at a desired frequency of around 2.45GHz has been designed and optimized using full wave electromagnetic software for its use in a highly compact antenna that requires zero phase shift. Equivalent circuit of the resonator based on modified composite right left hand transmission line (MCRLHTL) has been obtained and results have been compared with microstrip realization on FR4 epoxy substrate with relative permittivity=4.4 and thickness=1.6mm. The ZOR that is impedance matched with quarter wave transformer depicts monopolar radiation pattern with resonant frequency of 2.49GHz whereas the antenna when impedance matched with single stub tuning depicts patch like radiation pattern with resonant frequencies of 2.42GHz and 2.51GHz.