Monopulse Leaky Wave Antennas for RSSI-Based Direction Finding in Wireless Local Area Networks

We investigate the use of a single leaky wave antenna (LWA) for amplitude-monopulse direction finding when compared to the more conventional use of two tilted antennas. Thanks to the inherent bidirectional feeding and scanning behavior of LWAs, it is demonstrated a more compact and planar design while offering similar functionality in the far field. The frequency beam squinting effect suffered by the LWA, and its capability to create frequency-scanned monopulse patterns, are also analyzed; moreover, its smaller size mitigates the near-field effects, thus reporting a superior localization performance in the proximity of the antenna. This is experimentally demonstrated with prototypes designed in the 2.4 GHz ISM band, which are subsequently applied for direction finding of mobile devices connected to a Wi-Fi network.