Compact radiator antenna: A new approach to enhance the bandwidth using ENG-TL and C-CSRR mushroom meta-resonator

This work presents a new and efficient approach for enhancing the bandwidth and reducing the E-plane cross-polarization (X-pol) of an epsilon negative transmission line (ENG-TL) antenna with reduced size for working in 2.4 GHz Industrial, Scientific and Medical (ISM) band. The antenna consists of ENG-TL on which a curved meander line inductor is loaded for the generation of zeroth-order resonance mode. Subsequently, a miniaturized and low profile (0.06 lambda(0) x 0.06 lambda(0) x 0.013 lambda(0) at 2.44 GHz) circular-complementary split-ring resonator (C-CSRR) based mushroom meta-resonator is stacked over the ENG-TL antenna enhances the bandwidth twice without increasing any additional area. The proposed antenna provides a radiating element size of 0.17 lambda(0) x 0.15 lambda(0) excluding the feedline and total antenna dimension including ground plane is 0.17 lambda(0) x 0.20 lambda(0) x 0.025 lambda(0) at 2.45 GHz. The measured results shows an enhanced impedance bandwidth (IBW) of 7.40%, an acceptable gain of 2.8 dBi, and X-pol value better than 35 dB is obtained for the E-plane. The antenna compactness, extended IBW, low X-pol levels, improved gain, high gain-to-area ratio, and acceptable radiation efficiency indicates that the proposed antenna is appropriate for working in 2.4 GHz (2.4-2.484 GHz) ISM band.

Automated summary

This work presents a new efficient approach for enhancing antenna bandwidth and reducing cross-polarization in the 2.4 GHz ISM band, utilizing ENG-TL antenna with loaded meander line inductor and mushroom meta-resonator. The proposed antenna achieves extended bandwidth, low cross-polarization levels, improved gain, and high gain-to-area ratio, making it suitable for the specified frequency range.