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A new pattern‐reconfigurable antenna with the function of 360° wide‐beam scanning and main beam direction finely‐adjustable is proposed in this letter. The antenna consists of a central feeding disc which surrounded by four snowflake radiators on the top layer of the FR4 substrate. PIN diodes are placed between the disc and each snowflake patch for realizing the wide‐angle beam steering of the antenna. By controlling the four PIN diodes on the top layer, main beam can be switched in four directions with about 90° steps in the H‐plane (17°, 106°, 197°, and 287°).The bottom layer of the substrate includes a ground plane with eight rectangular ring slots. Eight PIN diodes installed on each slot are used to further control the beam direction of the antenna. By controlling the states of the PIN diodes on the bottom layer, the main beam of the proposed antenna is capable to deflect rightward or leftward about 10° on the basis of the original four states. The simulated and measured results show that the antenna operates well at 3.64–3.88 GHz under 12 states and achieves good performance with flexible pattern reconfigurability in 12 directions. The proposed antenna could be applied in 5G wireless communication systems.

In this letter, a new dual‐band circularly polarized (CP) planar monopole antenna is proposed. Simply by embedding an asymmetrical T‐shaped strip into the arc‐shaped feedline, dual‐band operation and CP radiation can be obtained. Furthermore, adding an inverted‐L‐shaped strip to the previous designing, the axial ratio bandwidths (ARBWs) can be greatly improved. After fabricating and then testing, the measured results indicate that the impedance bandwidths (IBWs) below 10‐dB can reach 240 MHz (2.39‐2.63 GHz) and 2.73 GHz (3.85‐6.58 GHz), and the 3‐dB ARBW can cover 260 MHz (2.26‐2.52 GHz) and 2.48 GHz (3.9‐6.38 GHz). The designed antenna can be applied to the WLAN (2.4/5.2/5.8‐GHz) and WiMax (5.5 GHz) multi‐function and multi‐mode communication systems felicitously.