Circularly polarized sequentially rotated antenna array for dual‐band WLAN applications

Abstract

This article presents a dual‐band circularly polarized (CP) 2 × 2 sequentially rotated (SR) antenna array with four slot antennas, a wideband sequential‐phase shifter (SPS), and reflected plane for wireless local area network (WLAN) operations. By designing the four slot antennas for dual‐band CP operations, the wideband SPS including four outputs with a sequential phase shift of 90° for improving bandwidth, and a conductor‐backed reflected plane for enhancing antenna gain, a high‐gain and dual‐band CP SR antenna array can be realized. The measured impedance bandwidth for return loss of 10 dB is 93.81% (2.36‐6.5 GHz). Both measured CP bandwidths for axial ratio of 3 dB are 22.64% (2.35‐2.95 GHz) and 49.16% (4.5‐6.77 GHz), which can cover all the WLAN bands. Maximum antenna gains are 12.32, 9.91, and 11.66 dBic in the range of 2.4 to 2.484, 5.15 to 5.35, and 5.725 to 5.875 GHz, respectively.

A novel single‐layer dual‐band circularly polarized metasurface antenna for maritime communications

“…Finally, the antenna achieved a 3 dB axial ratio bandwidth of 22.2% and a maximum gain of 9.3 dBic at 6.9 GHz. Other similar works were reported with various shaped MTSs in references, [7][8][9][10][11] All of them showed good circular polarization performance with the help of the MTS.…”