An Eight-Beam Switchable Antenna Based on Butler Matrix for Intelligent Application of Mobile Communication

In this paper, eight-beam switchable antennas based on $4\times 4$ butler matrix for intelligent applications of mobile communication is proposed. The antenna can provide different radio wave coverage according to the requirement of the communication scene to improve the communication quality, and the structure is relatively simple. The eight-beam switchable antenna for one-dimensional radio wave coverage uses two rows of $1\times 4$ microstrip patch array with different element spacing as the radiation unit, and the eight-beam switchable antenna for two-dimensional radio wave coverage uses two rows of $1\times 4$ microstrip patch array with the same element spacing as the radiation unit. $4\times 4$ butler matrix together with PIN diodes are used as the feed network of the antennas. By switching the exciting port of butler matrix and controlling the on-off states of the PIN diodes, eight-beam switching for one-dimensional and two-dimensional radio wave coverage is realized.