Mode investigation of parasitic annular ring loaded dual band coplanar waveguide antenna with polarization diversity characteristics

Abstract

This document presents a dual band dual polarized coplanar waveguide (CPW) antenna with single port feed. Lower resonating band is circular polarized, while the upper band is linear polarized. A novel concept of realizing dual polarization by suppressing the undesired modes is introduced in this work. Orthogonal Even/Odd modes are excited at lower band and a phase difference of 90° is maintained between them. Hence, circular polarization behavior is realized for lower operating band. For upper band, Odd mode is suppressed by introducing step shaped modifications in the ground plane at left side of the feed line, resulting in linear polarized upper band. Dual band nature of the antenna is confirmed by 10 dB impedance bandwidth extending from 3.91‐5.31 GHz to 7.51‐8.72 GHz. Circular polarized nature of lower band is confirmed by enclosure of lower band by 3 dB axial ratio bandwidth extending from 4.01 to 5.59 GHz. Advantages of proposed antenna involves the use of single port feed for generating dual polarization performance along with compact antenna size.(30 × 30 × 1.6 mm3).

A Compact Dual Band Dual Polarized Monopole Antenna With Enhanced Bandwidth for C, X, and Ku Band Applications

“…These novel design elements helped in obtaining measured dual IBWs from 5.85-6.52 GHz and 7.25-13.64 GHz, and the measured dual ARBWs from 7.22-10.99 GHz and 11.67 GHz-12.25 GHz. This is the widest IBW with wide ARBWs obtained compared to the earlier cited related designs antenna [4][5][6][7]. This antenna gives flexibility in dual-band dual-polarization operations in a single device, which is desired for replacing multiple apparatus.…”

“…Their CP characteristics also help in effectively combatting multipath interference or fading. To satisfy these requirements of DBDP antennas showing both linear and circular polarizations, different techniques have been utilized by various researchers [4][5][6][7]. An asymmetric dipole like radiator coupled with a T-shaped feed line having wide ground plane slot was used [4] to obtain dual-band characteristics.…”

“…FR4-epoxy and PTFE) to provide LP in lower band and CP in upper band. Another DBDP antenna with single port coplanar waveguide (CPW) feed [7] was designed to obtain LP in lower band and CP in upper band.…”