A compact complementary split ring resonator (CSRR) based perfect metamaterial absorber for energy harvesting applications

A novel Compact Complementary Split Ring Resonator (CSRR) metamaterial unit cell with perfect absorption, beneficial for ambient power harvesting, is proposed to operate in the S- and C-band. The size of the structure is 15 × 15 × 1.575 mm3 with dimensions of 0.18λ0 × 0.18λ0 × 0.019λ0 at the lowest absorption frequency. The proposed compact-sized CSRR structure exhibits notable characteristics such as high absorption coefficients and polarization-insensitive behaviours across a wide range of angles. The results demonstrate a notably high absorption efficiency of 97%, 99%, and 98% at 3.7275 GHz, 4.7075 GHz, and 5.9325 GHz. A 3 × 3 array is designed and verified by experimental results. The proposed design exhibits superior performance compared to previously published designs, which suffer from significant limitations such as a large metamaterial structure, reduced absorption frequency bands, and a lower fraction of absorption bands. The proposed design exhibits potential for utilization in developing wireless sensor network applications that require compact and highly efficient harvesting systems