Enhanced ADR for LoRaWAN networks with mobility

Abstract

LoRa is becoming an attractive low cost and low power WAN solution for many real-world IoT applications. LoRa has been designed for static end-devices to individually use the optimal configuration through an adaptive data rate mechanism (ADR), thanks to the possibility to choose a set of LoRa physical layer transmission parameters. However a large class of IoT applications (e.g. connected farm) also includes mobile nodes with specific mobility patterns. For those applications, the current ADR control algorithm may not be efficient when the radio channel attenuation rapidly changes because of the node mobility. This paper contributes to enhance the ADR mechanism by taking into account the position of the mobile devices and their trajectories in order to have a dynamic allocation. The Enhanced-ADR (E-ADR) minimizes the transmission time and energy consumption as well as packet loss for mobile devices. The testbed-based experiments show that E-ADR improves the quality of service (QoS) of the overall networks.

Proof of Concept of an IoT-Based Public Vehicle Tracking System, Using LoRa (Long Range) and Intelligent Transportation System (ITS) Services

“…Although the Dragino gateway was located in the roof of a tall building (approximately 25 meters), it was not possible to obtain LoS with most sections of the routes, and the obstacles were considerable (mainly, other buildings). To improve the percentage of received messages, we researched some other possible causes and solutions [21][22][23]. We found out that the main cause of the high percentage of lost packets was actually due to a large number of obstacles in the LoS and the Spread Factor used because the value of 7 has a low range.…”

“…One possible way to modify the relevant LoRa parameters is through an adaptive data rate (ADR) algorithm [23], which features an automatic learning method using the di erent transmission parameters. However, considering the low number of devices in our experiment and the low number of parameters to modify, we consider this approach is not necessary in our case.…”

“…is might be due to some particularity of the LoRaWAN protocol, or the processing done in the test. We reviewed literature in this regard [21][22][23] trying to find a solution and ran some tests related to data rate and access channels (detailed in experiment 2). Finally, we achieved connection to the LoRaWAN in an acceptable time of a few seconds; however, connection through LoRa messages proved to be faster.…”

“…In this experiment (third), we performed tests with LoR-aWAN in the OTAA mode, showing that the devices took much time registering on the network. e cause for this long connection delay was researched [21][22][23]. We found out that a LoRaWAN operates in several frequency channels that are determined by the gateway con guration.…”

Mobility-Aware Resource Assignment to IoT Applications in Long-Range Wide Area Networks

“…The resource allocation issues in LoRaWANs have been studied mostly for static EDs [9]- [12]. However, limited attention is paid to resource management when EDs are mobile [13]. The primary aim of these schemes is to enhance the packet success ratio (PSR).…”