A Compact Novel Multi-Band Monopole Antenna for WLAN/WiMAX/Sub-6 GHz 5G Applications

Abstract

In this work, a compact novel multi-band monopole radiator with multiple resonant branches is introduced for the Wireless Local Area Network (WLAN), Worldwide Interoperability for Microwave Access (WiMAX),and Sub-6 GHz 5G wireless applications. It is realized on an FR-4 substrate of 16 x 24 mm² compact footprint, which is more compact than the other similar multi-band designs in the literature. The monopole radiator comprises the partial ground plane with the multiple branches of (i) larger and shorter branches of the split etched loop, (ii) inverted E-shaped branch, (iii) rectangular stub. The optimized antenna geometry provides a good return loss performance of  -24, -39, -19, and -17 dB at the operating frequencies of 2.45, 3.5, 4.2, and 5.8 GHz. It achieves an impedance bandwidth of 100 MHz (2.4 – 2.5 GHz), 200 MHz (3.4 – 3.6 GHz), and 2200 MHz (4 – 6.2 GHz) in the lower, middle, and higher bands, respectively, to provide wireless connectivity for the 2.4, 5.2, and 5.8 GHz bands of WLAN,  3.5GHz band of WiMAX, and   Sub-6 GHz 5G n79 band (4.4 – 5 GHz)applications. The presented multi-band antenna reports peak gains of 1.1, 2.4, 2.7, and 4.1 dBi at the 2.45, 3.5, 4.2, and 5.8 GHz resonant frequencies. Similarly, the antenna accomplishes 72, 91, 94, and 95% radiation efficacies at the operating frequencies. The introduced multi-band design can be used as anappropriate candidate for portable wireless devices as it exhibits compact features with a very good port and radiation characteristics.