A Study of a Novel Triple- Broadband, Dual- Polarized Antenna with High Isolation and Low Cross - Polarization

A Study of a Novel Triple- Broadband, Dual- Polarized Antenna with High Isolation and Low Cross - Polarization

A design of a novel triple-broadband antenna for mobile communications is presented. The reference antenna is composed of an L-shape microstrip line which feeds a pair of folded dipoles by coupling. The bandwidth of this structure in each band is widened by introducing a pair of coordinate crossovers and manipulating the parameters of parasitic elements. It is shown that the presence of crossovers in the proposed design causes a nearly complete impedance match to the source in both printed dipoles. The proposed antenna achieves a bandwidth of 54% with return loss less than -10 dB for the first band, covering a frequency range of 1.2-2.1 GHz, which is suitable for 2G/3G applications. An 11% for the second band, with a frequency range of 3.4-3.8 GHz, suitable for WiMAX services. Also, a 14% for the third band with frequency coverage of 5.35-6.15 GHz, meant for WLAN applications. A ±450 dual-polarized element is also presented, which is based on the proposed antenna element. The numerical simulations are carried out by High Frequency Structure Simulator (HFSS) and then the results are confirmed with measurements.