Active FSS enclosed beam-switching node for wireless sensor networks

A wireless node with beam-switching and beam-sweeping features for wireless sensor networks (WSNs) is proposed. A readily available VirtualSense wireless node which makes use of 2.4GHz IEEE 802.15.4 wireless transceivers, as well as active cylindrical slot frequency selective surfaces (FSSs) are employed. The active FSS is made up of twelve columns with four hybrid slots each, dividing the cylinder by 30^o. The dimension of the cylinder is calculated to enclose the node with a folded dipole antenna in the center, so that compactness can be maintained. By changing the configuration of the active PIN diodes, omnidirectional and swept directional signal transceiving of nodes can be switched agilely. The work can make communication in nodes controllable depending on the demands of application, and bring flexibility and compatibility in WSNs.