1. Liu H, Darabi H, Banerjee P, Liu J (2007) Survey of wireless indoor positioning techniques and systems. IEEE Trans Syst Man Cybern C Appl Rev 37(6):1067–1080
2. Honkavirta V, Perälä T, Ali-Löytty S, Piché R (2009) Comparative survey of WLAN location fingerprinting methods. In: Workshop on positioning, navigation and communication. IEEE Press, New York, pp 243–251
3. Bahl P, Padmanabhan VN (2000) RADAR: An In-building RF-based user location and tracking system. In: IEEE International conference on computer communications, pp. 775–784 (2). IEEE Press, New York
4. Kessel M, Werner M (2011) SMARTPOS: Accurate And precise indoor positioning on mobile phones. In: International conference on mobile services, resources, and users. IARIA XPS Press, pp 158–163
5. Liao I-E, Kao K-F (2008) Enhancing the accuracy of WLAN-based location determination systems using predicted orientation information. Inform Science 178(4):1049–1068