New RSSI-based tracking for following mobile targets using the law of Cosines

Lately, there has been increasing interest for collecting and analyzing large amounts of data, produced by humans or mobile devices, to generate valuable knowledge. There is a common case where proximity is required between a monitoring device and a mobile target of interest, thus, a Hunter-Prey scenario needs to be implemented. The aim of this letter is to propose a new received signal strength indicator-based tracking technique, based on the Law of Cosines, which can be applied efficiently to the scenario described above. The new algorithm is evaluated through a series of simulation tests and results indicate that it outperforms common techniques such as linear least squares estimators

Location-Enabled IoT (LE-IoT): A Survey of Positioning Techniques, Error Sources, and Mitigation

The Internet of Things (IoT) has started to empower the future of many industrial and mass-market applications. Localization techniques are becoming key to add location context to IoT data without human perception and intervention. Meanwhile, the newly-emerged Low-Power Wide-Area Network (LPWAN) technologies have advantages such as long-range, low power consumption, low cost, massive connections, and the capability for communication in both indoor and outdoor areas. These features make LPWAN signals strong candidates for mass-market localization applications. However, there are various error sources that have limited localization performance by using such IoT signals. This paper reviews the IoT localization system through the following sequence: IoT localization system review -- localization data sources -- localization algorithms -- localization error sources and mitigation -- localization performance evaluation. Compared to the related surveys, this paper has a more comprehensive and state-of-the-art review on IoT localization methods, an original review on IoT localization error sources and mitigation, an original review on IoT localization performance evaluation, and a more comprehensive review of IoT localization applications, opportunities, and challenges. Thus, this survey provides comprehensive guidance for peers who are interested in enabling localization ability in the existing IoT systems, using IoT systems for localization, or integrating IoT signals with the existing localization sensors