In this paper, a four switchable beam antenna dedicated to Wireless Sensor Network (WSN) nodes in the 2.4 ISM band (2.4-2.485 GHz) is presented. It consists of two fed monopoles and two loaded parasitic ones. The nature and value of the load are obtained using the Uzkov equations, allowing to determine current weighting coefficients in the case of two separately fed antennas, in order to maximize the gain and the directivity in a given direction. Reconfigurability is achieved using reflector and director elements activated by PIN diodes to reduce the back radiation and pointing in the desired direction. Thus, a first system is obtained which consists of two elements, one fed and the other loaded with an inductor, with a maximum gain of 5.2 dBi in simulation and 4.7 dBi measured at 2.4 GHz in azimuthal directions of 90˚ and 270˚. Then, the system is compared with another, composed of two antennas fed separately. Finally, the same methodology is applied to an array of four antennas, in which two antennas are fed, and two are loaded. This last structure is capable of steering its radiation pattern in the azimuth plane, covering a 360˚ angle with four beams (0˚, 90˚, 180˚ and 270˚). The total gain achieved is 4 dBi for each beam in the azimuth plane.
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