Wideband dual‐polarised electromagnetic‐fed patch antenna with high isolation and low cross‐polarisation

Abstract

A wideband dual-polarised patch antenna with high isolation and a low cross-polarisation level is presented. Two orthogonal linearly-polarised modes are excited by the electromagnetic-fed structure. One of the two modes is excited by a pair of hook-shaped probes with a 180 o phase difference; while the other is excited by a magnetic-coupled loop, which is comprised of a metal loop and an open-ended transmission line. By introducing two shorting pins, the isolation between two feeding ports can be enhanced to more than 40 dB. Moreover, the radiation patterns in the ± 45°planes have a cross-polarisation level of less than − 30 dB within the 3 dB beam widths. The measured − 10 dB reflection coefficients bandwidth of the two modes are 40.7% (2.45-3.7 GHz) and 38.7% (2.6-3.85 GHz). The gains of the proposed antenna are about 8.7 and 9.1 dBi over the operating band. Thus, this antenna is highly suitable for the base station antenna that is required to cover the operating bandwidth of 3.5 GHz WiMAX systems.

Broadband Dual-Polarized Stacked Patch Antenna with High Isolation

“…As the isolation between two orthogonal polarization ports plays a vital role, substantial efforts have been made to improve it. The methods could be using slot-coupled feed [2], hybrid feeds [3], dual-feed for single port [4], dual capacitive feeds with open-circuited microstrip stubs [5] or slot loaded technique [6] and so on.…”

A broadband proximity-coupled dual-polarized microstrip antenna with L-shape backed cavity for X-band applications

“…In particular, since the microstrip antenna has attractive features, such as low profile, light weight and easy fabrication, it becomes one of the primary choices for implementing the dual-polarized radiation [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. However, the disadvantage of conventional microstrip antennas is the limited frequency bandwidth.…”

“…Toward this issue, many advanced techniques have been presented in recent years to design broadband dual-polarized microstrip antennas. These techniques include using the shaped slotted patch [9], stacked patch [10][11][12], shaped probe feed [13], and electromagnetic feed [14]. For example, in [11], * Corresponding author.…”

Wideband Planar Inverted-F Mimo Antenna With High Isolation

“…In recent years, many methods have been explored to deal with the isolation characteristic of a MIMO system [2][3][4][5][6][7][8][9][10][11]. In the design of [2], a folded resonator with about half a guided wavelength placed above the antenna is used to improve the isolation.…”

“…In [8], a tree-like structure is proposed to suppress surface wave propagation so as to reduce mutual coupling between radiating elements, and the measured isolation in the whole bandwidth exceeds 16 dB. In [9], two shorting pins are introduced to reduce the coupling between the feeding ports, and the isolation can be enhanced to more than 40 dB. High port isolation is implemented by employing anti-phase feeding technique [10,11].…”