Power Wide Area Network Technology Research Articles

Wearable Fall Detectors Based on Low Power Transmission Systems: A Systematic Review

Early attention to individuals who suffer falls is a critical aspect when determining the consequences of such accidents, which are among the leading causes of mortality and disability in older adults. For this reason and considering the high number of older adults living alone, the development of automatic fall alerting systems has garnered significant research attention over the past decade. A key element for deploying a fall detection system (FDS) based on wearables is the wireless transmission method employed to transmit the medical alarms. In this regard, the vast majority of prototypes in the related literature utilize short-range technologies, such as Bluetooth, which must be complemented by the existence of a gateway device (e.g., a smartphone). In other studies, standards like Wi-Fi or 3G communications are proposed, which offer greater range but come with high power consumption, which can be unsuitable for most wearables, and higher service fees. In addition, they require reliable radio coverage, which is not always guaranteed in all application scenarios. An interesting alternative to these standards is Low Power Wide Area Network (LPWAN) technologies, which minimize both energy consumption and hardware costs while maximizing transmission range. This article provides a comprehensive search and review of that works in the literature that have implemented and evaluated wearable FDSs utilizing LPWAN interfaces to transmit alarms. The review systematically examines these proposals, considering various operational aspects and identifying key areas that have not yet been adequately addressed for the viable implementation of such detectors.

Assessment of the dynamic parameters of a 673-meter cable-stayed bridge with wireless three-component MEMS-based sensors

Dynamic structural monitoring of bridges under ambient vibrations is a method to assess dynamic parameters of structures with low intrusiveness, e.g. with Operational Modal Analysis (OMA) data processing. Yet, several barriers hinder its adoption for real world applications, such as a lack of adequate sensors or industrial sensor networks and more generally, a lack of integrated solutions. In this paper, we present a data collection campaign using a novel wireless sensing system for dynamic structural monitoring of civil engineering structures. The core enabler of this SHM product named S-lynks is the use of a novel ultra-low noise seismic MEMS accelerometer, QuietSeisTM, which makes possible to envision a true industrial wireless sensor network for OMA in civil engineering structures. We developed a bespoke wireless sensing system composed of Wireless Sensor Nodes (WSN) and Gateways (WSG) and combining Low Power Wide Area Network (LPWAN) and Wireless Local Area Network (WLAN) technologies to manage the WSN wake up, synchronization and data transmission to WSG. This product has been used on a 675-meter cable-stayed bridge to assess the dynamic parameters from ambient vibrations measurements. We successfully triggered 120 measure points on the deck and inside a tower in less than 10 hours. More than 20 modes are identified between 0 and 5 Hz, with well-defined mode shapes. Extra measurements on a few cables to identify the tension allow explaining the asymmetry observed in some mode shapes.

Description and analysis of Sigfox received signal strength indicator dataset by using statistical techniques

Low power wide area network (LPWAN) technology has expanded and is essential in the development of applications for the internet of things (IoT). The Sigfox LPWAN network is characterized by its long-range coverage, low cost and power consumption. In this article, a set of 5174 values is analyzed, containing 1606 null RSSI data, obtained with the Sipy module and MicroPython, which provide a coverage map of several points with a resolution of 200 meters deployed in Quito–Ecuador. It is evaluated the type of distribution to which the set of network measurements is adjusted and an optimal 900 MHz propagation model in suburban environments is determined from the measurements obtained from the known base station. As a result, the lost values of RSSI were predicted using the inverse normal distribution method in the original values, observing that they conform to a logistic distribution. The data from the base station were subjected to a data augmentation algorithm designed in MATLAB, determining that the stanford university interim (SUI) model reduces the precision error in the trend of the curve by not presenting changes greater than 5 dB, achieving a precision of 97% with respect to the fit of the curve of the data.

INVESTIGATION OF THE FEATURES OF THE APPLICATION OF LORAWAN TECHNOLOGY IN AUTOMATIC SYSTEMS

The proliferation of the Internet of Things (IoT) has led to an increasing demand for efficient and scalable communication technologies to support automatic systems. Low Power Wide Area Network (LPWAN) technologies, such as Long Range Wide Area Network (LoRaWAN), have emerged as promising solutions for connecting a myriad of IoT devices. This research investigates the features and applications of LoRaWAN technology in automatic systems. The study begins with a comprehensive review of LoRaWAN technology, exploring its key attributes, including long-range communication, low power consumption, and wide coverage. We delve into the unique advantages that LoRaWAN offers in the context of automatic systems, such as smart cities, industrial automation, and agricultural monitoring. Furthermore, the research examines the challenges and limitations associated with LoRaWAN deployment, considering factors such as network congestion, security, and scalability. Through empirical analysis and case studies, we evaluate the real-world performance of LoRaWAN in diverse automatic system scenarios. The findings of this study contribute to a deeper understanding of the capabilities and limitations of LoRaWAN technology in supporting automatic systems. It informs practitioners, researchers, and policymakers about the potential applications and challenges of integrating LoRaWAN into IoT ecosystems for enhanced automation.

Potenciando el Desarrollo de IoT con Tecnología LPWAN: Caso de Estudio en la Universidad Nacional de Misiones

This document underscores the vital role of Low Power Wide Area Network (LPWAN) technology in advancing the Internet of Things (IoT) and enabling connectivity for low-power devices, prioritizing factors like range, durability, and cost-efficiency. It explores the influences on LPWAN performance, including Ultra Narrow Band (UNB) and Spread Spectrum (SS) modulations, offering in-depth insights into their technical characteristics, pros, and cons across licensed and unlicensed operational spectrums. Notable challenges encompass battery life, quality of service, coverage, and expenditure. The city of Posadas, Argentina, is showcased as a successful LoRaWAN testbed, illustrating the system’s commendable performance and functionality.

Coverage Analysis of LoRa and NB-IoT Technologies on LPWAN-Based Agricultural Vehicle Tracking Application

This study focuses on the recently emerged Internet of Vehicles (IoV) concept to provide an integrated agricultural vehicle/machinery tracking system through two leading low power wide area network (LPWAN) technologies, namely LoRa and NB-IoT. The main aim is to investigate the theoretical coverage limits by considering the urban, suburban, and rural environments. Two vehicle tracking units (VTUs) have been designed for LoRa and NB-IoT connectivity technologies that can be used as reference hardware in coverage analysis. On this basis, the closed-form explicit analytical expressions of the maximum transmission range have been derived using the Hata path loss model. Besides, the computer simulation results have been validated via the maps from XIRIO online radio planning tool. In light of the obtained findings, several evaluations have been made to enhance the LPWAN-based agricultural vehicle tracking feasibility in smart farms.

FEMTOSAT-Based Air Quality Monitoring: Leveraging Satellite Data and LoRa Communication for Improved AQI Predictions

The exponential growth of the global population has given rise to an alarming surge in air pollution levels, casting profound repercussions on economies, ecosystems, and human well-being. The predominant method for assessing air quality involves the deployment of sensors atop buildings at regular intervals. However, this approach faces significant drawbacks, including heightened energy consumption associated with each building's sensor infrastructure and its inapplicability in sparsely populated rural areas. Addressing these limitations, the utilization of FEMTOSAT technology emerges as a solution, capitalizing on satellite data for autonomous air pollution monitoring, analysis, and mitigation. Amidst the evolving scientific landscape, the integration of Low Power Wide Area Network (LoRa) technology assumes a pivotal role within the Internet of Things (IoT), facilitating long-range data communication with minimal power consumption. In this context, LoRa communication serves as the conduit for transmitting and receiving data from satellites via RF signals. The satellite-derived environmental data, thus collected, serves as the foundation for computing the Air Quality Index (AQI) at specific locations, a critical metric that informs us about air quality conditions, whether pristine or contaminated. The AQI computation factors in various pollutants, including NO2, CO, O3, PM2.5, SO2, and PM10, all of which significantly influence air quality. This study employs a range of machine learning (ML) techniques, including time series analysis, linear regression, Support Vector Machines (SVM), and logistic regression, to predict and forecast AQI values. These models amalgamate AQI data from diverse sources, yielding robust and dependable AQI prediction models. Notably, modern sensor technology simplifies and enhances data collection accuracy. In the realm of environmental data analysis, only ML algorithms can grapple with the complexity of processing vast datasets to generate precise and trustworthy predictions. The incorporation of integrated sensors as payload in the Femto Sat mission epitomizes the mission's objectives. This system is characterized by its cost-effectiveness, lightweight design, durability, redundancy, and user-friendly interface, requiring minimal power consumption for operation.

Delay Optimization in LoRaWAN by Employing Adaptive Scheduling Algorithm With Unsupervised Learning

Low Power Wide Area Network (LPWAN) technologies have been exponentially growing because of the tremendous growth of the Internet of Things (IoT) devices across the globe. Several LPWAN technologies have been utilized by the researchers to address certain issues like increased number of collisions, retransmissions, delay, and energy consumption. However, Long Range Wide Area Network (LoRaWAN) is the most suitable and attractive technology in terms of delay optimization, low cost and efficient energy consumption. The main issue which arises in LoRaWAN is because of its high packet drop rate due to collision. The reason behind this packet drop rate is the MAC scheme known as Pure Aloha used by LoRaWAN for the transmission of the frames. Long Range (LoRa) End Devices (EDs) initiate communication with Pure Aloha that leads to a high number of retransmissions. These retransmissions further enhance the delay in LoRa networks. This paper aims to optimize the delay in LoRaWAN by using an Adaptive Scheduling Algorithm (ASA) with an unsupervised probabilistic approach called Gaussian Mixture Model (GMM). By using ASA with GMM, the retransmissions are reduced which optimizes the delay in LoRaWAN. The results show that in our approach, Packet Collision Rate (PCR) is reduced by 39% as compared to conventional LoRaWAN. In addition, the Packet Success Ratio (PSR) is also increased by 39% as compared to the conventional LoRaWAN and Dynamic Priority Scheduling Technique (PST). Further, the delay is optimized by 91% and 79%. This research could be effective for the environments where the critical data of patients need to be sent with optimised retransmissions and minimum delay towards gateways.

A comparative study on LPWAN standards: Nb-IoT and LTE-M

Given the proliferation of connected objects as well as the rise of Low Power Wide Area Network (LPWAN) technologies designed to enable communication with low energy, the main ones being NB-IoT and LTE-M in our daily life. This is why in this article; our study will focus on the evaluation of the specificities of these two standards: NB-IoT and LTE-M

A Survey on Evolved LoRa-Based Communication Technologies for Emerging Internet of Things Applications

Survey/review study A Survey on Evolved LoRa-Based Communication Technologies for Emerging Internet of Things Applications Fang Yao 1,3, Yulong Ding 2,3,*, Shengguang Hong 2,4, and Shuang-Hua Yang 2,5,* 1 The Ta-tech company, Nanjing 210009, China 2 Shenzhen Key Laboratory of Safety and Security for Next Generation of Industrial Internet, Department of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China 3 Department of Computer Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China 4 The School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150006, China 5 Department of Computer Science, University of Reading, West Berkshire RG6 6UR, United Kingdom * Correspondence: dingyl@sustech.edu.cn; Shuang-hua.yang@reading.ac.uk Received: 17 September 2022 Accepted: 17 October 2022 Published: 22 December 2022 Abstract: The concept of Internet of Things (IoT) greatly extends the coverage area that human being is able to perceive, access, and even control. By connecting various “Things” to the Internet, the IoT makes it possible to measure and manage the physical world as needed. As one of the most widely adopted Low Power Wide Area network technologies, the Long-Range-Radio (LoRa) has the features of long range, low power, and robustness, and thus plays an important role in building IoT applications where IoT objects are connected to the internet at affordable costs. Since the development of LoRa, many IoT applications have adopted LoRa and achieved success in the market. Currently, IoT technologies keep evolving towards different fields, giving rise to multifarious IoT applications including industrial IoT, smart city IoT, healthcare IoT, and direct-to-satellite IoT. In the meantime, LoRa also keeps developing and finding its position in various IoT applications either as a main or complementary player. The objective of this survey is to (1) provide a fundamental understanding of the LoRa technology; (2) explore research activities studying LoRa based communication systems for new IoT applications; and (3) demonstrate how the LoRa technology works together with other technologies to deliver better IoT services to end users.

Energy Consumption of IoT Devices: An Accurate Evaluation to Better Predict Battery Lifetime

AbstractLoRa to say Long Range is one of the Low Power Wide Area Network technologies suitable for Internet of Things due to its low power consumption. In this paper we evaluate the energy consumption of a LoRa network using the LoRaWAN protocol which is based on the pure Aloha access method. We define a reference scenario (scenario 0), which consists in neglecting the energy consumption related to the different states of the end‐devices after transmission of a packet that does not require downlink acknowledgment and then we compare this scenario 0 to scenario 1, scenario 2 and scenario 3. Indeed the scenario 1 consists in considering the states of the end‐devices after transmission in uplink of a packet without acknowledgment, in the evaluation of the energy consumption. However, scenario 2 takes into account the different states of the end‐devices in scenario 1 with an acknowledgment on the first reception window. While in scenario 3 the acknowledgment is done on the second reception window always taking into account the end‐devices states. The simulation results with the LoRaSim tool have shown that the network energy consumption (NEC) increases significantly when considering the different states of the end‐device after uplink transmission of a packet without acknowledgment, but also that the increase of the NEC related to end‐device states is even more important if packets are acknowledged. Thus for a rigorous evaluation of the NEC, it is important to take into account the states of the end‐device after transmission of a packet but also the eventual acknowledgments in order to better predict the battery lifetime.

From Demodulation to Decoding: Toward Complete LoRa PHY Understanding and Implementation

LoRa, as a representative of Low Power Wide Area Network technology, has attracted significant attention from both academia and industry. However, the current understanding of LoRa is far from complete, and implementations have a large performance gap in SNR and packet reception rate. This article presents a comprehensive understanding of LoRa physical layer protocol (PHY) and reveals the fundamental reasons for the performance gap. We present the first full-stack LoRa PHY implementation with a provable performance guarantee. We enhance the demodulation to work under extremely low SNR (-20 dB) and analytically validate the performance, where many existing works require SNR > 0. We derive the order and parameters of decoding operations, including dewhitening, error correction, deinterleaving, and so on, by leveraging LoRa features and packet manipulation. We implement a complete real-time LoRa on the GNU Radio platform and conduct extensive experiments. Our method can achieve (1) a 100% decoding success rate while existing methods can support at most 66.7%, (2) -142 dBm sensitivity, which is the limiting sensitivity of the commodity LoRa, and (3) a 3,600-m communication range in the urban area, even better than commodity LoRa under the same setting.

Mechanism for IPv6 adaptation in LoRa topologies

One of the main requirements of an IoT solution is the support of end-to-end IPv6 connectivity. Most Wireless Personal Area (WPAN) physical and link layers like Bluetooth Low Energy (BLE), ITU-T G.9959 and IEEE 802.15.4 support adaptation mechanisms that, based on the IPv6 over Low Power Wireless Personal Area Networks (6LoWPAN) protocol, enable IPv6. On the other hand, Low Power Wide Area Network (LPWAN) technologies like LoRa and SigFox are not typically designed to support access-side IPv6 and rely on gateways for translation and overall cloud connectivity. Lack of end-to-end IPv6 connectivity implies that many of these LPWAN technologies do not fully comply with the IoT paradigm preventing the direct interaction between devices of different physical technologies. In this paper we present an adaptation mechanism that enables end-to-end IPv6 support in an LPWAN scenario that relies on a LoRa physical layer. The scheme is analyzed, modeled and implemented by means of an experimental framework that serves to examine the efficiency of the proposed solution.

Secure proxy MIPv6-based mobility solution for LPWAN

With the advancement and the wide deployment of the Internet of Things, Low Power Wide Area Network (LPWAN) technologies will respond to applications requiring low power and long range features. In this context, mobility is an additional requirement needed by several applications including supply chain monitoring and health-care supervision. Proxy Mobile IPv6 (PMIPv6) as an extension of Internet Protocol (IP) is used in the LPWAN protocol stack since it provides mobility management. But PMIPv6 does not provide secure access for mobile nodes joining to the network. In this paper, we propose a new mobility solution for LPWAN based on PMIPv6 and we provide a new authentication mechanism to achieve secure access to the network. Thereafter, we evaluate the performance of the proposed solution by simulation using the Network Simulator 3 (NS-3) and by theoretical analysis. Moreover, the security of the proposed authentication mechanism is assessed using an informal security analysis as well as using the AVISPA validation tool. Finally, we compare the performance of our solution with other proposed solutions where we show the improvements made by our solution with respect to several parameters and requirements.

Time-slotted LoRa MAC with variable payload support

LoRaWAN is an upcoming Low Power Wide Area Network (LPWAN) technology for Internet of Things implementations in various application domains. Despite its various advantages, LoRaWAN employs an Aloha-based MAC, which in terms of performance cannot guarantee high packet delivery ratio and low latency. To overcome this issue, we propose a time-slotted scheme, called TS-VP-LoRa, which supports multiple transmission times and packet sizes at the same time. In TS-VP-LoRa, scheduling is coordinated by the LoRa gateway, broadcasting beacon frames periodically for the synchronization of LoRa end-devices. A channel hopping mechanism is also proposed in order to minimize the occurrence of collisions and to evenly split the transmission load among all channels. TS-VP-LoRa is evaluated and compared to three other MAC-layer schemes in single gateway simulation scenarios with up to 500 nodes. The proposed scheme has proven to achieve low latency with high packet delivery ratios, significantly minimize collisions and maintain a relatively low energy consumption despite the scaling of the LoRa network.

A Configurable Mathematical Model for Single-Gateway LoRaWAN Performance Analysis

LoRaWAN is a Low Power Wide Area Network technology featuring long transmission ranges and a simple MAC layer, which can support sensor data collection, control applications and reliable services thanks to the flexibility offered by a large set of configurable system parameters. However, the impact of such parameters settings on the system’s performance is often difficult to predict, depending on several factors. To ease this task, in this paper, we provide a mathematical model to estimate the performance of a LoRaWAN gateway serving a set of devices that may or may not employ confirmed traffic. The model features a set of parameters that can be adjusted to investigate different gateway and end-device configurations, making it possible to carry out a systematic analysis of various trade-offs. The results given by the proposed model are validated through realistic ns-3 simulations that confirm the ability of the model to predict the system performance with high accuracy, and assess the impact of the assumptions made in the model for tractability.

Packet Fragmentation Over Sigfox: Implementation and Performance Evaluation of SCHC ACK-on-Error

The static context header compression and fragmentation (SCHC) framework has been recently designed by the Internet engineering task force (IETF). SCHC provides adaptation layer functionality intended to efficiently support IPv6-based and other applications over low power wide area network (LPWAN) technologies. As of the writing, technology-specific profiles are being standardized in order to describe how SCHC can be tailored when used over a given underlying technology. In this article, we provide the first performance evaluation of SCHC over Sigfox, a flagship LPWAN technology. We focus on the main SCHC over Sigfox fragmentation mode, called ACK-on-Error, which offers low overhead, reliability, and reassembly functionalities. We provide a theoretical analysis and an experimental evaluation in real environments that correspond to two geographical zones with different Sigfox radio settings: 1) Barcelona (Spain) and 2) Santiago (Chile). The study focuses on modeling and evaluating packet transfer times, and the required number of uplink and downlink messages. The results show that a small change in packet sizes may significantly affect the transfer times, especially when no duty-cycle restrictions are enforced. Also, we observe that, under certain conditions, an increase in the fragment loss rate (FLR) may decrease the packet transfer time, and that the number of uplink and downlink messages is not proportional to such increase due to the fact that downlink messages are device-driven. The results provide useful insights for researchers, developers, implementers, and providers, with applicability to the application design, network planning, and resource management of Internet of Things (IoT) solutions.

Low Power Wide Area Network Technologies: Open Problems, Challenges, and Potential Applications

Nowadays, the number of internet of things (IoT) connected devices continues to increase exponentially. However, the core underlying wireless network technologies that enable IoT devices to achieve such growth and wide applications face numerous challenging deployment requirements such as operating range, power consumption, and cost. Low-power wide-area network (LPWAN) technologies enable long-distance, low-power, and low data transmission at a low cost. These new wireless technologies shape the IoT ecosystem due to their wide applications. This study aims to review the various features and analyze the performances of the leading LPWANs, namely LoRa, SigFox, NB-IoT, and Weightless. Initially, precise descriptions of their underlying technologies and various applications were provided. Then, several challenges facing the LPWANs and potential solutions were outlined. Finally, the study analyzed their performance against several specifications, including frequency range, Bandwidth, Modulation, and so on. The outcome shows that these technologies are more efficient than the short and medium-range IoT technologies, particularly regarding power, range, and cost. The study’s findings are hoped to provide a guide and eliminate LPWAN technology selection issues.

Analysis and optimization of downlink energy in NB-IoT

The efficient and simpler version of Internet of things (IoT) is Narrowband Internet of Things (NB-IoT). It is a low power wide area network (LPWAN) technology standardized by Third Generation Partnership Project (3GPP) and is mainly used for LPWA applications. The deployment of NB-IoT is easy and it utilizes low power. To extend the possibilities of NB-IoT in terms of coverage, traffic and power,efficient energy consumption has become a concern. In this paper, the NB-IoT model has been analysed with respect to the reception of downlink (DL) packets. Energy optimization of downlink packet has been done with the help of particle swarm optimization (PSO). By optimizing the non-constraint parameters of NB-IoT,84.98% and 61.07% decrease in energy consumption has been observed. Overall, average energy efficiency of the system has been increased. The non-optimized and optimized NB-IoT systems have been critically compared.

Analysis of LoRaWAN 1.0 and 1.1 Protocols Security Mechanisms.

LoRaWAN is a low power wide area network (LPWAN) technology protocol introduced by the LoRa Alliance in 2015. It was designed for its namesake features: long range, low power, low data rate, and wide area networks. Over the years, several proposals on protocol specifications have addressed various challenges in LoRaWAN, focusing on its architecture and security issues. All of these specifications must coexist, giving rise to the compatibility issues impacting the sustainability of this technology. This paper studies the compatibility issues in LoRaWAN protocols. First, we detail the different protocol specifications already disclosed by the LoRa Alliance in two major versions, v1.0 and v1.1. This is done through presenting two scenarios where we discuss the communication and security mechanisms. In the first scenario, we describe how an end node (ED) and network server (NS) implementing LoRaWAN v1.0 generate session security keys and exchange messages for v1.0. In the second scenario, we describe how an ED v1.1 and an NS v1.1 communicate after generating security session keys. Next, we highlight the compatibility issues between the components implementing the two different LoRaWAN Specifications (mainly v1.0 and v1.1). Next, we present two new scenarios (scenarios 3 and 4) interchanging the ED and NS versions. In scenario three, we detail how an ED implementing LoRaWAN v1.1 communicates with an NS v1.0. Conversely, in scenario four, we explain how an ED v1.0 and an NS v1.1 communicate. In all these four scenarios, we highlight the concerns with security mechanism: show security session keys are generated and how integrity and confidentiality are guaranteed in LoRaWAN. At the end, we present a comparative table of these four compatibility scenarios.