Multi-band different polarized monopole antenna with modified ground for WLAN & Wi-MAX applications

This paper presents the design and analysis of a multi-band, dual-polarised monopole antenna consisting of a simple equilateral triangular monopole patch configured with a modified ground structure (MGS). In the presented antenna design, quad-band dual-polarised operation has been obtained by creating the three unequal rectangular slots on the ground structure. The proposed monopole antenna produces four individual frequency bandwidths with the dual sense of polarisation, namely linear polarisation (LP) and circular polarisation (CP). The antenna produces quad-band behaviour with linear wave polarisation in Band1, whereas right-hand circular polarisation (RHCP) in rest frequency bands viz. Band2, Band3, and Band4. The measured impedance bandwidths spread from 2.50 to 4.42 GHz in band2; 5.22 to 6.28 GHz in band3; and 8.40 to 10.30 GHz in band4; whereas the impedance bandwidth extends from 1.35 to 2.14 GHz in linearly polarised band 1. The measured axial ratio bandwidth (ARBW) extends from 2.82 to 3.20 GHz in band2; 5.17 to 5.94 GHz in band3; and 9.30 to 9.70 GHz in band4, respectively. The constant gain profile has been observed in all frequency bands. The proposed antenna can be applied for WLAN/ WiMAX and Wi-Fi applications.