Beam Forming Network Design Using 4×4 Butler Matrix for ISM Band-III (24GHz) Applications

Beam steering antennas are the perfect solution for the diversity of system utilization, mostly attained by using a phased array where phase shifters are used to command the respected main beam of the desired radiation pattern. In this paper, we designed a unidirectional antenna that operates at Industrial Scientific Medical (ISM) band III (24 GHz). A Beam Forming Network (BFN) called Butler Matrix comprising of a Branch Line Coupler (BLC) and the Crossovers. These all are designed concerning the operating frequency. A 4×4 Butler Matrix is designed and by providing a power source at each port of the input side respectively, and an antenna at each port of output side the beam pattern can be steered at the angles of +50°,+20°, _20°,_50°. The intelligibility of the design makes it acceptable for ISM Band III applications.