# Feasibility of LoRa for Smart Home Indoor Localization
## 5 Conclusions  
LoRa is one of wireless telecommunications systems, and this system could provide long-range, low-power, low-bitrate data transmission. Meanwhile, LoRa has a strong performance of interference elimination and high network efficiency. These characteristics reveal that LoRa could be potentially used in the IoT and location-based services (LBS).  
This research demonstrates the feasibility of LoRa for indoor localization applications. Firstly, we compare the strengths and weaknesses of existing technologies used for indoor localization. Then, the practical experiment evaluates the accuracy and the precision of LoRa localization in both LOS and NLOS conditions in a furnished home setting where the localization area is relatively smaller than offices or corporate buildings. The experimental results show that LoRa localization could achieve accuracies better than 1.6 m in LOS and 3.1 m in extreme NLOS conditions. In all cases, the precision is better than 25 cm. In addition, the results suggest that LoRa can be used for some indoor localization applications, even with a simple implementation without using any signal or data filtering. For instance, initial locations of multiple mobile assistive robots can be estimated without input from human users. Initial pose estimate is an important step in indoor robot localization followed by probabilistic adjustment of the location and orientation using sensors attached to the robots. With longer range communication and higher penetration capabilities, LoRa can be considered a promising technology that combines communication and localization.  
After our preliminary experiments, a few problems related to the LoRa's use in the smart home indoor localization are revealed and they need to be studied in future research. For example, the accuracy of indoor localization can be increased by optimizing the three-dimensional positioning algorithm to satisfy more application scenarios. By doing so, coordinates of tags can be more accurately determined to allow users to locate objects, such as small electronic devices, in the building precisely. The 3.1 m accuracy under NLOS in this study would still benefit users to find objects easily or utilize location-based assistance using the rough coordinates of tags. However, more precise locations obtained by optimizing the performances could reduce potential errors, such as false alarms and incorrect locations of objects. Also, the LoRa localization technology system could extend into mobile applications, which lets end-users access the needed location-based information anytime and anywhere. Our research team will conduct further studies to improve the applicability of LoRa in smart home indoor localization.  
Conceptualization, K.K. and J.I.K.; methodology, K.K. and M.H.; software development, M.H. and N.S.; hardware prototyping, M.H.; validation, K.K. and M.J.S.; formal analysis, N.S. and O.G.; investigation, W.S.; data curation, O.G.; writing--original draft preparation, S.L. and J.I.K.; writing--review and editing, W.S. and M.J.S.; visualization, S.L. and N.S.; supervision, K.K. and J.I.K. All authors have read and agreed to the published version of the manuscript. This research was funded by City University of Hong Kong, grant number 7200593. Institutional Review Board Statement: Not appliable. Informed Consent Statement: Not appliable. Data Availability Statement: Not appliable. Conflicts of Interest: The authors declare no conflict of interest.