Low Power Wide Area Network Technologies Research Articles

Energy Consumption Model of SCHC Packet Fragmentation over Sigfox LPWAN.

The Internet Engineering Task Force (IETF) has standardized a new framework, called Static Context Header Compression and fragmentation (SCHC), which offers adaptation layer functionality designed to support IPv6 over Low Power Wide Area Networks (LPWANs). The IETF is currently profiling SCHC, and in particular its packet fragmentation and reassembly functionality, for its optimal use over certain LPWAN technologies. Considering the energy constraints of LPWAN devices, it is crucial to determine the energy performance of SCHC packet transfer. In this paper, we present a current and energy consumption model of SCHC packet transfer over Sigfox, a flagship LPWAN technology. The model, which is based on real hardware measurements, allows to determine the impact of several parameters and fragment transmission strategies on the energy performance of SCHC packet transfer over Sigfox. Among other results, we have found that the lifetime of a device powered by a 2000 mAh battery, transmitting packets every 5 days, is 168 days for 2250-byte packets, while it increases to 1464 days for 77-byte packets.

Insights into the Issue of Deploying a Private LoRaWAN.

The last decade has transformed wireless access technologies and crystallized a new direction for the internet of things (IoT). The modern low-power wide-area network (LPWAN) technologies have been introduced to deliver connectivity for billions of devices while keeping the costs and consumption low, and the range of communication high. While the 5G (fifth generation mobile network) LPWAN-like radio technologies, namely NB-IoT (narrowband internet of things) and LTE-M (long-term evolution machine type communication) are emerging, the long-range wide-area network (LoRaWAN) remains extremely popular. One unique feature of this technology, which distinguishes it from the competitors, is the possibility of supporting both public and private network deployments. In this paper we focus on this aspect and deliver original results comparing the performance of the private and public LoRAWAN deployment options; these results should help understand the LoRaWAN technology and give a clear overview of the advantages and disadvantages of the private versus public approaches. Notably, we carry the comparison along the three dimensions: the communication performance, the security, and the cost analysis. The presented results illustratively demonstrate the differences of the two deployment approaches, and thus can support selection of the most efficient deployment option for a target application.

SCHC over LoRaWAN Efficiency: Evaluation and Experimental Performance of Packet Fragmentation.

Low Power Wide Area Networks (LPWAN) are expected to enable the massive connectivity of small and constrained devices to the Internet of Things. Due to the restricted nature of both end devices and network links, LPWAN technologies employ network stacks where there is no interoperable network layer as a general case; instead, application data are usually placed directly into technology-specific two-layer frames. Besides not being able to run standard IP-based protocols at the end device, the lack of an IP layer also causes LPWAN segments to operate in an isolated manner, requiring middleboxes to interface non-IP LPWAN technologies with the IP world. The IETF has standardized a compression and fragmentation scheme, called Static Context Header Compression and Fragmentation (SCHC), which can compress and fragment IPv6 and UDP headers for LPWAN in a way that enables IP-based communications on the constrained end device. This article presents a model to determine the channel occupation efficiency based on the transmission times of SCHC messages in the upstream channel of a LoRaWAN™ link using the ACK-on-Error mode of standard SCHC. The model is compared against experimental data obtained from the transmission of packets that are fragmented using a SCHC over LoRaWAN implementation. This modeling provides a relationship between the channel occupancy efficiency, the spreading factor of LoRa™, and the probability of an error of a SCHC message. The results show that the model correctly predicts the efficiency in channel occupation for all spreading factors. Furthermore, the SCHC ACK-on-Error mode implementation for the upstream channel has been made fully available for further use by the research community.

LoRa Networking Techniques for Large-scale and Long-term IoT: A Down-to-top Survey

Low-Power Wide-Area Networks (LPWANs) are an emerging Internet-of-Things (IoT) paradigm, which caters to large-scale and long-term sensory data collection demand. Among the commercialized LPWAN technologies, LoRa (Long Range) attracts much interest from academia and industry due to its open-source physical (PHY) layer and standardized networking stack. In the flourishing LoRa community, many observations and countermeasures have been proposed to understand and improve the performance of LoRa networking in practice. From the perspective of the LoRa networking stack; however, we lack a whole picture to comprehensively understand what has been done or not and reveal what the future trends are. This survey proposes a taxonomy of a two-dimensional (i.e., networking layers, performance metrics) to categorize and compare the cutting-edge LoRa networking techniques. One dimension is the layered structure of the LoRa networking stack. From down to the top, we have the PHY layer, Link layer, Media-access Control (MAC) layer, and Application (App) layer. In each layer, we focus on the three most representative layer-specific research issues for fine-grained categorizing. The other dimension is LoRa networking performance metrics, including range, throughput, energy, and security. We compare different techniques in terms of these metrics and further overview the open issues and challenges, followed by our observed future trends. According to our proposed taxonomy, we aim at clarifying several ways to achieve a more effective LoRa networking stack and find more LoRa applicable scenarios, leading to a brand-new step toward a large-scale and long-term IoT.

Performance evaluation of LoRa based sensor node and gateway architecture for oil pipeline management

These days, the oil industrial industry is leaning toward employing smart field improvements to streamline various activities in the midstream area. Oil transportation over large distances via pipelines has a cheap cost and high efficiency in this sector. If pipelines are not properly maintained, they may fail, potentially causing catastrophic, long-term, and irreversible consequences on both natural and human conditions. Low power wide area networks (LPWANs) are without a doubt one of the domains that cause the most from industrial fields when it comes to realizing the vision of the internet of things (IoT). Long-range (LoRa) is an emerging LPWAN technology that is particularly useful for transmitting data over long distances. The goal of this work is to offer a methodology for managing oil pipelines over long distances utilizing the LoRa communication protocol and the installation of sensor nodes and LoRa gateways along the pipeline. We also used the optimized network engineering tools (OPNET) simulator to examine various simulation findings of LoRa performance.

A Survey on LoRaWAN Technology: Recent Trends, Opportunities, Simulation Tools and Future Directions

Low-power wide-area network (LPWAN) technologies play a pivotal role in IoT applications, owing to their capability to meet the key IoT requirements (e.g., long range, low cost, small data volumes, massive device number, and low energy consumption). Between all obtainable LPWAN technologies, long-range wide-area network (LoRaWAN) technology has attracted much interest from both industry and academia due to networking autonomous architecture and an open standard specification. This paper presents a comparative review of five selected driving LPWAN technologies, including NB-IoT, SigFox, Telensa, Ingenu (RPMA), and LoRa/LoRaWAN. The comparison shows that LoRa/LoRaWAN and SigFox surpass other technologies in terms of device lifetime, network capacity, adaptive data rate, and cost. In contrast, NB-IoT technology excels in latency and quality of service. Furthermore, we present a technical overview of LoRa/LoRaWAN technology by considering its main features, opportunities, and open issues. We also compare the most important simulation tools for investigating and analyzing LoRa/LoRaWAN network performance that has been developed recently. Then, we introduce a comparative evaluation of LoRa simulators to highlight their features. Furthermore, we classify the recent efforts to improve LoRa/LoRaWAN performance in terms of energy consumption, pure data extraction rate, network scalability, network coverage, quality of service, and security. Finally, although we focus more on LoRa/LoRaWAN issues and solutions, we introduce guidance and directions for future research on LPWAN technologies.

Low-Power Wide-Area Networks: A Broad Overview of Its Different Aspects

Low-power wide-area networks (LPWANs) are gaining popularity in the research community due to their low power consumption, low cost, and wide geographical coverage. LPWAN technologies complement and outperform short-range and traditional cellular wireless technologies in a variety of applications, including smart city development, machine-to-machine (M2M) communications, healthcare, intelligent transportation, industrial applications, climate-smart agriculture, and asset tracking. This review paper discusses the design objectives and the methodologies used by LPWAN to provide extensive coverage for low-power devices. We also explore how the presented LPWAN architecture employs various topologies such as star and mesh. We examine many current and emerging LPWAN technologies, as well as their system architectures and standards, and evaluate their ability to meet each design objective. In addition, the possible coexistence of LPWAN with other technologies, combining the best attributes to provide an optimum solution is also explored and reported in the current overview. Following that, a comparison of various LPWAN technologies is performed and their market opportunities are also investigated. Furthermore, an analysis of various LPWAN use cases is performed, highlighting their benefits and drawbacks. This aids in the selection of the best LPWAN technology for various applications. Before concluding the work, the open research issues, and challenges in designing LPWAN are presented.

Coverage and Energy-Efficiency Experimental Test Performance for a Comparative Evaluation of Unlicensed LPWAN: LoRaWAN and SigFox

Low Power Wide Area Networks (LPWAN) have emerged as an appealing IoT communication solution. Large coverage and low power consumption are critical requirements when deploying a communication network to support an IoT application. Despite the fact that existing LPWAN technology solutions promote IoT requirements such as long communication range, energy efficiency, scalability, and low cost, there are numerous concerns about the performance of this type of communication network. With a wide range of LPWAN technologies available, there is growing interest in their evaluation. This paper proposes an experimental comparative evaluation based on coverage and energy-efficiency test performance for LoRaWAN and SigFox, two emerging LPWAN technologies operating in sub-GHz Industrial, Scientific, and Medical (ISM) frequency bands. Recent works have presented various comparison studies of LPWAN technologies, however most of them have been tackled from the perspective of comparing their technical specifications without presenting measurement results obtained from network deployment scenarios. We argue that by proposing a comparative evaluation from an experimental perspective, the comparison discussion is taken to the next level. The experimental evaluation has been proposed first by selecting coverage and energy-efficiency as the most significant design goals for LPWAN applications. Second, by proposing the test performance to evaluate those goals, where extensive measurements are made in network deployments, and finally, by highlighting the main findings about performance for both network for comparison purposes. Results show that in a test with fair conditions LoRaWAN performed better than SigFox in an urban environment in terms of coverage, obtaining a better packet delivery rate (PDR ≳ 80%) with higher radio strength signal (RSSI ≳ - 110 dBm). Whereas Sigfox shows better energy efficiency with a 20 % of more sent messages under the same test conditions.

Setting up an IoT lecture for Centrale Lille: A LoRa(WAN)™-based labwork, from data transmission to data visualization

As part of the education reform of the École Centrale de Lille, a new lecture for the “Internet of Things” has been created. Entitled “Mobile networks, IoT and UHS (Ultra High Speed) communications” and taught in English it takes place in the “Advanced communication networks” teaching unit (UE) for the third year students of the École Centrale de Lille engineering curriculum as well as for master students enrolled in Centrale Lille. In this lecture, students acquire knowledge about cellular networks, new LPWAN (Low Power Wide Area Network) technologies such as LoRa™ or Sigfox™ and UHS communications. The labwork focuses on the LoRa(WAN) protocol, where students create their first and complete IoT application, from data transmission to data visualization using popular applications/software. The lab-work is based on a “problem analysis/problem resolution” (PAPR) approach where students first need to analyze what they observe and finally need to propose solutions to avoid encountered problems based on knowledge acquired during the lecture.

Assessment of LoRaWAN Transmission Systems Under Temperature and Humidity, Gas, and Vibration Aging Effects Within IIoT Contexts

Within the big picture of the Internet of Things (IoT), a brand new paradigm has risen since few years ago in the context of industrial scenarios: the industrial IoT (IIoT), whose aim is to transplant all of the features, characteristics, and scopes of the IoT into industrial settings. The latter ones might be subject to a wide range of environmental conditions from the point of view of both temperature and relative humidity, along with harmful gases exposure and vibration due to, for instance, machinery. Therefore, whenever their monitoring is performed by means of devoted infrastructures, such extreme working conditions must be born in mind during the pertaining design phases. Mostly, industrial monitoring is put into effect by resorting to wireless sensor networks (WSNs) enabled by low-power wide area network (LPWAN) technologies. This set of facilities includes an ample heterogeneity of standards and techniques. However, the long-range (LoRa) modulation and the LoRa wide area network (LoRaWAN) protocol extensively proved to be reliable and robust alternatives. Thus, in this article, the variations of hardware performances of a LoRaWAN sensor node, in terms of transmission capabilities, due to the changes of temperature and relative humidity, vibration, and gaseous atmospheres, such as CO, NO, and NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , which are typical of industrial processes, are investigated. In so doing, an aging process due to the aforementioned phenomena was induced. To this end, a measurement campaign within controlled environments (i.e., a climatic chamber, a fume extraction plant, and an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ad hoc</i> vibration test bench) was sorted out, whose results show a physiological performances drop that neither undermines the network reliability nor damages the sensor node electronics.

Experimental test and performance of RSSI-based indoor localization in LoRa Networks

LoRa (Long Range) is a wireless communication technology, which has established itself in recent years as one of the most widely used LPWAN (Low-Power Wide-Area Network) technologies in various IoT (Internet of things) applications. It is based on Chirp spread spectrum modulation (CSS) in which the number of bits per symbol depends on the spreading factor used, that varies from 7 to 12. In this paper, we have considered the RSSI (Received Signal Strength Indicator) parameter in the indoor environment. For LoRa, we use the LoRa transceiver based on two HTCC AB01 modules for their ability to modify the spreading factor (SF). In our work, we transmit in the 868MHz frequency band, and we use a bandwidth 125 KHz and three spreading factors SF7, 9 and 12. Subsequently, we tried to measure RSSI in an indoor environment with a short distance under LOS and NLOS conditions for three spreading factors. We sent the temperature measured by the DHT11 sensor from the transmitter to the receiver to measure the RSSI for each distance and for each spreading factor. The experimental results show that LoRa can be used in an indoor context, and that the spreading factor improve the performance of this technology in terms of RSSI. Moreover, the power losses of the received signal are more important in the NLOS conditions compared to those observed in the LOS conditions.

LoRaWAN Base Station Improvement for Better Coverage and Capacity

Low Power Wide Area Network (LPWAN) technologies provide long-range and low power consumption for many battery-powered devices used in Internet of Things (IoT). One of the most utilized LPWAN technologies is LoRaWAN (Long Range WAN) with over 700 million connections expected by the year 2023. LoraWAN base stations need to ensure stable and energy-efficient communication without unnecessary repetitions with sufficient range coverage and good capacity. To meet these requirements, a simple and efficient upgrade in the design of LoRaWAN base station is proposed, based on using two or more concentrators. The development steps are outlined in this paper and the evaluation of the enhanced base station is done with a series of measurements conducted in Zagreb, Croatia. Through these measurements we compared received messages and communication parameters on novel and standard base stations. The results showed a significant increase in the probability of successful reception of messages on the novel base station which corresponds to the increase of base station capacity and can be very beneficial for the energy consumption of most LoRaWAN end devices.

LoRa: A Proposed Connectivity Technology for Internet of Things Applications in the Kurdistan Region of Iraq

The Internet of Things (IoT) has become one of the most important trends of this century. Recent advances in many different communication technologies and protocols, and access to low-cost and low-power microcontrollers and sensors have made it more prevalent. &#x0D; Globally, most IoT adoption comes from developed countries such as the United States, United Kingdom, Western Europe, and East Asia, as these countries have a well-established nationwide IoT infrastructure. In contrast, the IoT application in developing countries such as Kurdistan Region of Iraq (KRI) remains restricted as deployment faces main challenges. On the one hand, selecting the right technology for IoT applications can be complicated with so many IoT connectivity technologies such as Cellular, Wi-Fi, Low Power Wide Area Network (LPWAN), Bluetooth, and ZigBee on the market. On the other hand, the main impediment seems to be the lack of IoT infrastructure technologies in developing countries. &#x0D; In this paper, a comparative study on the main LPWAN technologies has been carried out in terms of cost and coverage of the network and range to become connectivity technology for IoT applications in the KRI. Based on the study, LoRa technology has been presented and proposed as the optimal connectivity technology to establish an IoT infrastructure for the KRI. The proposed network enables the deployment of IoT applications easier and faster. In addition, various LoRa based IoT applications have been proposed that benefit many sectors. A potential application has been set out as a case study to show case the significance of the new infrastructure. &#x0D; The proposed LoRaWAN infrastructure can accommodate a vast range of applications and will revolutionize IoT applications in the KRI as it enables data transmission over a long distance while using extremely low power.

Toward Ubiquitous Connectivity via LoRaWAN: An Overview of Signal Collision Resolving Solutions

The ever increasing demand for energy-efficient, long-range, and license-free Internet of Things (IoT) communication networks has spurred great interest in unlicensed low-power wide area networks (LPWANs). Such a revolutionary technology represents a paradigm shift in the development of wireless networks, as it can enable low-power (milliwatts) IoT devices to transmit at low data rates (kilobits per second) over long distances (several kilometers), which is clearly different from conventional IoT networking technologies (e.g., Wi-Fi and ZigBee) that only support short-range communications. Specifically, long-range WAN (LoRaWAN) is a leading and representative LPWAN technology that has been gathering remarkable attention from both academia and industry because of its open source software and installation ease. Despite this interest, however, current LoRaWAN is not yet a mature communication platform to provide ubiquitous connectivity for a wide variety of IoT applications. This is mainly because LoRaWAN typically serves a large volume of coexisting end devices among which signal collisions frequently occur at the physical layer (LoRa) of LoRaWAN, thereby leading to severe degradation of overall network capacity. In this context, the aim of this article is to provide a comprehensive overview of up-to-date physical-layer solutions for LoRa collision resolution. We particularly investigate different types of LoRa collisions resulting from the spreading factor network parameter. Moreover, the potential visions of physical-layer design to resolve LoRa collisions that might be considered for future research are also discussed.

LoRa Enabled Smart Inverters for Microgrid Scenarios with Widespread Elements

The introduction of low-power wide-area networks (LPWANs) has changed the image of smart systems, due to their wide coverage and low-power characteristics. This category of communication technologies is the perfect candidate to be integrated into smart inverter control architectures for remote microgrid (MG) applications. LoRaWAN is one of the leading LPWAN technologies, with some appealing features such as ease of implementation and the possibility of creating private networks. This study is devoted to analyze and evaluate the aforementioned integration. Initially, the characteristics of different LPWAN technologies are introduced, followed by an in-depth analysis of LoRa and LoRaWAN. Next, the role of communication in MGs with widespread elements is explained. A point-by-point LoRa architecture is proposed to be implemented in the grid-feeding control structure of smart inverters. This architecture is experimentally evaluated in terms of latency analysis and externally generated power setpoint, following smart inverters in different LoRa settings. The results demonstrate the effectiveness of the proposed LoRa architecture, while the settings are optimally configured. Finally, a hybrid communication system is proposed that can be effectively implemented for remote residential MG management.

Attack-aware Synchronization-free Data Timestamping in LoRaWAN

Low-power wide-area network technologies such as long-range wide-area network (LoRaWAN) are promising for collecting low-rate monitoring data from geographically distributed sensors, in which timestamping the sensor data is a critical system function. This article considers a synchronization-free approach to timestamping LoRaWAN uplink data based on signal arrival time at the gateway, which well matches LoRaWAN’s one-hop star topology and releases bandwidth from transmitting timestamps and synchronizing end devices’ clocks at all times. However, we show that this approach is susceptible to a frame delay attack consisting of malicious frame collision and delayed replay. Real experiments show that the attack can affect the end devices in large areas up to about 50,000, m 2 . In a broader sense, the attack threatens any system functions requiring timely deliveries of LoRaWAN frames. To address this threat, we propose a LoRaTS gateway design that integrates a commodity LoRaWAN gateway and a low-power software-defined radio receiver to track the inherent frequency biases of the end devices. Based on an analytic model of LoRa’s chirp spread spectrum modulation, we develop signal processing algorithms to estimate the frequency biases with high accuracy beyond that achieved by LoRa’s default demodulation. The accurate frequency bias tracking capability enables the detection of the attack that introduces additional frequency biases. We also investigate and implement a more crafty attack that uses advanced radio apparatuses to eliminate the frequency biases. To address this crafty attack, we propose a pseudorandom interval hopping scheme to enhance our frequency bias tracking approach. Extensive experiments show the effectiveness of our approach in deployments with real affecting factors such as temperature variations.

Impact of Compression and Small Cell Deployment on NB-IoT Devices Coverage and Energy Consumption with a Realistic Simulation Model

In the last few years, Low-Power Wide-Area Network (LPWAN) technologies have been proposed for Machine-Type Communications (MTC). In this paper, we evaluate wireless relay technologies that can improve LPWAN coverage for smart meter communication applications. We provide a realistic coverage analysis using a realistic correlated shadow-fading map and path-loss calculation for the environment. Our analysis shows significant reductions in the number of MTC devices in outage by deploying either small cells or Device-to-Device (D2D) communications. In addition, we analyzed the energy consumption of the MTC devices for different data packet sizes and Maximum Coupling Loss (MCL) values. Finally, we study how compression techniques can extend the battery lifetime of MTC devices.

ScienceIoT: Evolution of the Wireless Infrastructure of KREONET.

Here, we introduce the current stage and future directions of the wireless infrastructure of the Korea Research Environment Open NETwork (KREONET), a representative national research and education network in Korea. In 2018, ScienceLoRa, a pioneering wireless network infrastructure for scientific applications based on low-power wide-area network technology, was launched. Existing in-service applications in monitoring regions, research facilities, and universities prove the effectiveness of using wireless infrastructure in scientific areas. Furthermore, to support the more stringent requirements of various scientific scenarios, ScienceLoRa is evolving toward ScienceIoT by employing high-performance wireless technology and distributed computing capability. Specifically, by accommodating a private 5G network and an integrated edge computing platform, ScienceIoT is expected to support cutting-edge scientific applications requiring high-throughput and distributed data processing.

LPWAN and Embedded Machine Learning as Enablers for the Next Generation of Wearable Devices.

The penetration of wearable devices in our daily lives is unstoppable. Although they are very popular, so far, these elements provide a limited range of services that are mostly focused on monitoring tasks such as fitness, activity, or health tracking. Besides, given their hardware and power constraints, wearable units are dependent on a master device, e.g., a smartphone, to make decisions or send the collected data to the cloud. However, a new wave of both communication and artificial intelligence (AI)-based technologies fuels the evolution of wearables to an upper level. Concretely, they are the low-power wide-area network (LPWAN) and tiny machine-learning (TinyML) technologies. This paper reviews and discusses these solutions, and explores the major implications and challenges of this technological transformation. Finally, the results of an experimental study are presented, analyzing (i) the long-range connectivity gained by a wearable device in a university campus scenario, thanks to the integration of LPWAN communications, and (ii) how complex the intelligence embedded in this wearable unit can be. This study shows the interesting characteristics brought by these state-of-the-art paradigms, concluding that a wide variety of novel services and applications will be supported by the next generation of wearables.

LoRa Communications as an Enabler for Internet of Drones towards Large-Scale Livestock Monitoring in Rural Farms.

Currently, smart farming is considered an effective solution to enhance the productivity of farms; thereby, it has recently received broad interest from service providers to offer a wide range of applications, from pest identification to asset monitoring. Although the emergence of digital technologies, such as the Internet of Things (IoT) and low-power wide-area networks (LPWANs), has led to significant advances in the smart farming industry, farming operations still need more efficient solutions. On the other hand, the utilization of unmanned aerial vehicles (UAVs), also known as drones, is growing rapidly across many civil application domains. This paper aims to develop a farm monitoring system that incorporates UAV, LPWAN, and IoT technologies to transform the current farm management approach and aid farmers in obtaining actionable data from their farm operations. In this regard, an IoT-based water quality monitoring system was developed because water is an essential aspect in livestock development. Then, based on the Long-Range Wide-Area Network (LoRaWAN®) technology, a multi-channel LoRaWAN® gateway was developed and integrated into a vertical takeoff and landing drone to convey collected data from the sensors to the cloud for further analysis. In addition, to develop LoRaWAN®-based aerial communication, a series of measurements and simulations were performed under different configurations and scenarios. Finally, to enhance the efficiency of aerial-based data collection, the UAV path planning was optimized. Measurement results showed that the maximum achievable LoRa coverage when operating on-air via the drone is about 10 km, and the Longley–Rice irregular terrain model provides the most suitable path loss model for the scenario of large-scale farms, and a multi-channel gateway with a spreading factor of 12 provides the most reliable communication link at a high drone speed (up to 95 km/h). Simulation results showed that the developed system can overcome the coverage limitation of LoRaWAN® and it can establish a reliable communication link over large-scale wireless sensor networks. In addition, it was shown that by optimizing flight paths, aerial data collection could be performed in a much shorter time than industrial mission planning (up to four times in our case).