Improved Beam Steering Direction in Spiral Antenna Using PIN Diodes for Wireless Communication System

This paper introduces a novel spiral antenna design capable of generating four steerable beams for wireless communication. The antenna features a central circular disc surrounded by four stubs, with each stub supporting a spiral arm equipped with a PIN diode. A coaxial probe positioned at the center evenly distributes power to the four spiral arms. Operating within the Wi-Fi band at 2.45 GHz, the antenna can achieve four distinct operating states at the same frequency. Beam steering in four directions (0°±, 90°±, 180°±, and 270°±) is achieved by selectively activating and deactivating the PIN diodes. With a peak directivity of 5.79 dBi at 0°±, the antenna offers high performance and precise beam control.