Localization for Mobile Entities -- MGALE: A Modified Geometry-Assisted Location Estimation Algorithm Reducing Location Estimation Error in 2D Case under NLOS Environments -- Predicting User-Cell Association in Cellular Networks from Tracked Data -- Discovering Significant Places from Mobile Phones – A Mass Market Solution -- Adaptive Motion Model for a Smart Phone Based Opportunistic Localization System -- Localization Using RSSI -- Model-Free Probabilistic Localization of Wireless Sensor Network Nodes in Indoor Environments -- A Calibration-Free Localization Solution for Handling Signal Strength Variance -- Indoor Location and Orientation Determination for Wireless Personal Area Networks -- Localization with Novel Sensors -- Localize Vehicles Using Wireless Traffic Sensors -- On the Feasibility of Determining Angular Separation in Mobile Wireless Sensor Networks -- Controlling Error Propagation in Mobile-Infrastructure Based Localization -- Estimation of Indoor Physical Activity Level Based on Footstep Vibration Signal Measured by MEMS Accelerometer in Smart Home Environments -- Localization by Experiments -- Inferring Motion and Location Using WLAN RSSI -- WASP: An Enhanced Indoor Locationing Algorithm for a Congested Wi-Fi Environment -- A Long-Duration Study of User-Trained 802.11 Localization -- Invited Papers -- Tutorial on Location Determination by RF Means -- A Survey on Localization for Mobile Wireless Sensor Networks -- Performance of TOA- and RSS-Based Indoor Geolocation for Cooperative Robotic Applications.

This book constitutes the refereed proceedings of the second International Workshop on Mobile Entity Localization and Tracking in GPS-less Environnments, MELT, held in Orlando, Florida, USA, in September 2009 in conjunction with the 11th International Conference on Ubiquitous Computing (Ubicomp 2009). MELT is a forum for the state-of-the-art technologies in mobile localization and tracking and novel applications of location-based services. The research contributions in these proceedings cover significant aspects of localization and tracking of mobile devices that include techniques suitable for smart phones and mobile sensor networks in both outdoor and indoor environments using diverse sensors and radio signals. Novel theoretical methods, algorithmic design and analysis, application development, and experimental studies are presented in 14 papers that were reviewed carefully by the program committee. In addition, three invited papers, with topics on location determination using RF systems, Cramer-Rao-Bound analysis for indoor localization and approaches targeting mobile sensor networks, are also included in the proceedings.