Tunable high-gain and multiband microstrip antenna based on liquid/copper split-ring resonator superstrates for C/X band communication

We proposed a tunable, high-gain and multiband metamaterial microstrip antenna. The design structure is analysed using simulation results and measured results. The split-ring resonator superstrate and complementary split-ring resonator are used as metamaterial elements and loaded in microstrip patch antenna. The high gain is achieved by using the stacking of metamaterial superstrate above the microstrip patch antenna. We have presented the comparison of gain by loading split-ring resonator superstrate layers. The tunability is achieved by switching on and off p-i-n diodes. Three different combinations of six p-i-n diode switches are used for tuning the frequency spectrum. The improvement in bands is also achieved by different switching conditions. The liquid metamaterial superstrate shows a better response compared to the copper metamaterial superstrate. The results in terms of electric field are also presented. The design results are compared with previously published results. The proposed antenna with its tuning capacity and the high gain feature can be applied in wireless communication applications for C/X band communication.