Kensaku Kawauchi Takashi Miyaki Jun Rekimoto Directional Beaconing: A Robust WiFi Positioning Method Using Angle-of-Emission Information. 103-119 2009 LoCA http://dx.doi.org/10.1007/978-3-642-01721-6_7 conf/loca/2009 db/conf/loca/loca2009.html#KawauchiMR09