A LoRa-Based Mobile Localization Method In Urban Environment:Design And Implementation

In our daily lives,we can see all kinds of IoT devices everywhere,and how to manage these devices is a major challenge in the large-scale application of the Internet of Things.One of the Solutions is to install a localization system on these devices so that we can get the location of them in a real time.In addition,most of the applications provided by IoT sensing devices are location-based services.If the geographic location of the device is not known,the data which from sensor will be meaningless.Most location-based applications usually use GPS for localization.However,the energy consumption caused by GPS is very high,which is not suitable for low-power scenarios in the Internet of Things.Based on this,This paper proposes an outdoor mobile localization method in an urban environment based on LoRa.LoRa is a new wireless communication technology,which has the characteristics of long-distance communication and low power consumption at the same time,and is naturally suitable for scenarios in the Internet of Things.The innovation of this article is:using the environmental sensitivity of the LoRa signal,and its received signal strength indication RSSI is strongly correlated with the environment,this article uses the RSSI of the signal as the fingerprint information in the fingerprint localization scheme,and refer to the Okumura-Hata wireless signal propagation model to propose a new LoRa signal prediction model to generate a fingerprint database,which avoids the manual fingerprint collection process in the traditional fingerprint-based localization method,and improves the flexibility of the localization system.Compared with other outdoor wireless localization solutions,the advantage of this system is that no additional sensing equipment is needed,which reduces the cost of the system;And because of the popularization of LoRa technology,the deployment of the system is also convenient.The use of LoRa signals to estimate the location of the object can be used in various ranges of outdoor and indoor environments.In the research process of this subject,we conducted a large number of experiments and tested the system functionality in a real environment.The result shows that in an environment where the terrain around the node changes significantly,the localization accuracy of this system can reach within 10 meters,Even in areas with a large number of people and dense buildings,this solution can control the localization accuracy to about 30 meters,which is an acceptable localization error for the localization of IoT devices in an urban environment.