A compact multiband antenna using λ/4 rectangular stub loaded with metamaterial for IEEE 802.11N and IEEE 802.16E

This research article describes a compact multiband antenna using λ/4 rectangular stub, loaded with metamaterial for the frequency bands 2.4, 3.5, and 5.8 GHz allocated to IEEE 802.11n (WLAN) and IEEE 802.16e (WiMAX) standards in wireless communication. Compactness, multiband, and impedance matching operations in the proposed design are accomplished by utilizing a rectangular microstrip patch, a novel metamaterial based split ring resonator (SRR), a λ/4 rectangular stub and a ground plane. The proposed SRR negative permeability retrieval mechanism is explained in detail. The electrical dimensions of the designed antenna are 0.206 λ₀ × 0.174 λ₀ (25 × 22 mm²) at lower resonating band (2.4 GHz) and fabricated on a widely available FR4 substrate having 4.4 as dielectric constant and 1.6 mm as thickness. The average gain of 2.58 dBi, good impedance matching, stable radiation characteristics with high co-polarization value and return loss bandwidth of 13.7% (2.26–2.57 GHz), 10.09% (3.27–3.60 GHz) and 5.09% (5.69–5.98 GHz) are observed at the bands of operation when the antenna is fabricated and tested.