Investigation of the influence of the CSRR resonator parameters on the characteristics of a Ku-band microstrip SIW antenna

The paper presents the results of simulation of a Kuband microstrip substrate integrated waveguide antenna (SIW antenna) with a complementary split ring resonator (CSRR) using the computational electromagnetics code FEKO. Structural synthesis of the antenna design is used to study the influence of geometrical parameters of a resonator on the main antenna characteristics. The frequency dependences of the return loss, gain and voltage standing wave ratio in 9.5 - 13.5 GHz band are analyzed. The field distribution inside the antenna, the distribution of surface currents and the parameters of radiation patterns at resonant frequencies are also discussed. The research shows that the combination of substrate integrated waveguide technology and CSRR structure allows reducing the resonant frequency by 12.7% and obtaining the second resonant frequency, which is 8.5% higher in comparison with a SIW antenna without CSRR. It also leads to the improvement of the antenna parameters at the second resonant frequency, except for the operating band, which narrows by almost 1.5 times.