Multi-band microstrip-fed slot antenna loaded with split-ring resonator
A microstrip-fed compact multi-band slot antenna using a single split-ring resonator (SRR) is proposed. The SRR acting as a loading element introduces multiple lower-order resonances in the antenna, which can be controlled by varying the SRR's dimensions as well as its position with respect to the arm of the slot, without altering the geometry of the radiating slot. The concept is validated by a full-wave simulation study and by measurement on a fabricated prototype. The proposed antenna has satisfactory gain and monopolar radiation patterns in all the operating bands.