Performance Study of Rectangular Microstrip Patch Antennas with Split Ring Resonator Structure

In this paper a four element rectangular microstrip patch antenna is designed for 9.1GHz, with a peak gain of 10.09dB and peak sidelobe level of -10.74dB. By placing split ring resonator structures at height of half the wavelength above the antenna array, improvement in gain, 3dB gain bandwidth are observed with simultaneous reduction in peak sidelobe level. By placing these left handed split ring resonator structures above the array, shift in resonant frequency to 8.7GHz is also observed, which leads to frequency miniaturization. An improvement of 1.3dB in gain, 96.4MHz in 3dB gain bandwidth are observed at 8.7GHz, with 2.95dB reduction in peak sidelobe level. The simulations are carried using HFSS software and performance parameters are compared.