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1
Park, Jean, and Juyeop Kim. "An Implementation Design of Unified Protocol Architecture for Physical Layer of LoRaWAN End-Nodes." Electronics 10, no. 20 (October 19, 2021): 2550. http://dx.doi.org/10.3390/electronics10202550.
Повний текст джерелаАнотація:
LoRa Wide Area Networks (LoRaWAN) can provide a connectivity service to Internet of Things (IoT) for an extremely long run-time and with low power consumption. As the LoRaWAN is extensively applied to various IoT scenarios, LoRaWAN solutions face a flexibility issue in terms of inter-operating with various kinds of LoRa modem hardware and protocol scenarios. In this regard, we design a unified protocol architecture for LoRaWAN physical layer, which can flexibly correspond to various deployment and operational cases. The new protocol architecture includes a hardware abstraction sub-layer, which contains generalized handlers for configuring various kinds of the LoRa modem, and a physical procedure sub-layer that structurally models the physical layer procedures of the LoRaWAN based on Finite State Machine(FSM). We illustrate the flexibility of the new protocol architecture by implementing an extensive feature that enhances the packet reception ratio based on the status of preamble detection. For evaluating the new protocol architecture, we implement the LoRaWAN physical layer protocol on real-time embedded systems and conduct experiments. The experimental results show that the proposed protocol robustly transmits and receives packets and generates little amount of additional burden compared with the conventional open source protocol provided by SemTech.
2
Kim, Seungku, Heonkook Lee, and Sungho Jeon. "An Adaptive Spreading Factor Selection Scheme for a Single Channel LoRa Modem." Sensors 20, no. 4 (February 13, 2020): 1008. http://dx.doi.org/10.3390/s20041008.
Повний текст джерелаАнотація:
When the low power wide area network (LPWAN) was developed for the internet of things (IoT), it attracted significant attention. LoRa, which is one of the LPWAN technologies, provides low-power and long-range wireless communication using a frequency band under 1 GHz. A long-range wide area network (LoRaWAN) provides a simple star topology network that is not scalable; it supports multi-data rates by adjusting the spreading factor, code rate, and bandwidth. This paper proposes an adaptive spreading factor selection scheme for corresponding spreading factors (SFs) between a transmitter and receiver. The scheme enables the maximum throughput and minimum network cost, using cheap single channel LoRa modules. It provides iterative SF inspection and an SF selection algorithm that allows each link to communicate at independent data rates. We implemented a multi-hop LoRa network and evaluated the performance of experiments in various network topologies. The adaptive spreading factor selection (ASFS) scheme showed outstanding end-to-end throughput, peaking at three times the performance of standalone modems. We expect the ASFS scheme will be a suitable technology for applications requiring high throughput on a multi-hop network.
3
Slaný, Vlastimil, Adam Lučanský, Petr Koudelka, Jan Mareček, Eva Krčálová, and Radek Martínek. "An Integrated IoT Architecture for Smart Metering Using Next Generation Sensor for Water Management Based on LoRaWAN Technology: A Pilot Study." Sensors 20, no. 17 (August 20, 2020): 4712. http://dx.doi.org/10.3390/s20174712.
Повний текст джерелаАнотація:
This pilot study focuses on the design, implementation, optimization and verification of a novel solution of smart measuring of water consumption and crisis detection leading to a smart water management platform. The system implemented consists of a modular IoT platform based on a PCB (Printed Circuit Board) design using the M2.COM standard, a LoraWAN modem and a LoraWAN gateway based on the Raspberry Pi platform. The prototype is modular, low-cost, low-power, low-complex and it fully reflects the requirements of strategic technological concepts of Smart City and Industry 4.0, i.e., data integration, interoperability, (I)IoT, etc. The study was produced in cooperation with M.I.S Protivanov and VODARENSKA AKCIOVA SPOLECNOST, a.s. (industry partners distributing drinking water in the Olomouc and South-Moravian regions) to depict the current situation in the Czech Republic, characterized by extreme weather fluctuations and increasingly frequent periods of drought. These drinking water distributors are also constantly placing new demands on these smart solutions. These requirements include, above all, reliability of data transmission, modularity and, last but not least, low cost. However, smart water management (water consumption, distribution, system identification, equipment maintenance, etc.) is becoming an important topic worldwide. The functionality of the system was first verified in laboratory conditions and, then, in real operation. The study also includes checking signal propagation in the municipal area of the village of Zdarna, where the radius of the proposed measuring system was tested. A laboratory test with simulation of water leakage is also part of this work. Subsequently, the system was tested in a residential unit by means of water leakage detection using the MNF method (minimum night flow); the detection success rate was 95%.
4
Gu, Chaojie, Linshan Jiang, Rui Tan, Mo Li, and Jun Huang. "Attack-aware Synchronization-free Data Timestamping in LoRaWAN." ACM Transactions on Sensor Networks 18, no. 1 (February 28, 2022): 1–31. http://dx.doi.org/10.1145/3474368.
Повний текст джерелаАнотація:
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.
5
Gu, Chaojie, Linshan Jiang, Rui Tan, Mo Li, and Jun Huang. "Attack-aware Synchronization-free Data Timestamping in LoRaWAN." ACM Transactions on Sensor Networks 18, no. 1 (February 28, 2022): 1–31. http://dx.doi.org/10.1145/3474368.
Повний текст джерелаАнотація:
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.
6
Matni, Nagib, Jean Moraes, Helder Oliveira, Denis Rosário, and Eduardo Cerqueira. "LoRaWAN Gateway Placement Model for Dynamic Internet of Things Scenarios." Sensors 20, no. 15 (August 4, 2020): 4336. http://dx.doi.org/10.3390/s20154336.
Повний текст джерелаАнотація:
Extended Range Wide Area Network (LoRaWAN) has recently gained a lot of attention from the industrial and research community for dynamic Internet of Things (IoT) applications. IoT devices broadcast messages for neighbor gateways that deliver the message to the application server through an IP network. Hence, it is required to deploy LoRaWAN gateways, i.e., network planning, and optimization, in an environment while considering Operational Expenditure (OPEX) and Capital Expenditure (CAPEX) along with Quality of Service (QoS) requirements. In this article, we introduced a LoRaWAN gateway placement model for dynamic IoT applications called DPLACE. It divides the IoT devices into groups with some degree of similarity between them to allow for the placement of LoRaWAN gateways that can serve these devices in the best possible way. Specifically, DPLACE computes the number of LoRaWAN gateways based on the Gap statistics method. Afterward, DPLACE uses K-Means and Fuzzy C-means algorithms to calculate the LoRaWAN gateway placement. The simulations’ results proved the benefits of DPLACE compared to state-of-the-art LoRaWAN gateway placement models in terms of OPEX, CAPEX, and QoS.
7
Bankov, Dmitry, Evgeny Khorov, and Andrey Lyakhov. "LoRaWAN Modeling and MCS Allocation to Satisfy Heterogeneous QoS Requirements." Sensors 19, no. 19 (September 27, 2019): 4204. http://dx.doi.org/10.3390/s19194204.
Повний текст джерелаАнотація:
LoRaWAN infrastructure has become widely deployed to provide wireless communications for various sensor applications. These applications generate different traffic volumes and require different quality of service (QoS). The paper presents an accurate mathematical model of low-power data transmission in a LoRaWAN sensor network, which allows accurate validation of key QoS indices, such as network capacity and packet loss ratio. Since LoRaWAN networks operate in the unlicensed spectrum, the model takes into account transmission attempt failures caused by random noise in the channel. Given QoS requirements, we can use the model to study how the performance of a LoRaWAN network depends on the traffic load and other scenario parameters. Since in LoRaWAN networks the transmissions at different modulation and coding schemes (MCSs) typically do not collide, we use the model to assign MCSs to the devices to satisfy their QoS requirements.
8
Mukhamejanova, Almira D., Elans A. Grabs, Kumyssay K. Tumanbayeva, and Eleonora M. Lechshinskaya. "Traffic simulation in the LoRaWAN network." Bulletin of Electrical Engineering and Informatics 11, no. 2 (April 1, 2022): 1117–25. http://dx.doi.org/10.11591/eei.v11i2.3484.
Повний текст джерелаАнотація:
LoRaWAN is one of the most commonly used technologies serving the internet of things (IoT) and machine-to-machine (M2M) devices. The traffic growth in the LoRaWAN network gives rise to many problems, which are solved using mathematical modelling. The actual task, in this case, is the development of a traffic simulation model in the LoRaWAN network. This article discusses the issues of traffic simulation in the LoRaWAN network and its research using the MATLAB system. The authors have developed a LoRaWAN network server model as a queuing system with incoming self-similar traffic in the MATLAB system using a separate subsystem for the input traffic modelling allowing to change the number of sources in the LoRaWAN network. The simulation results made it possible to establish the dependences of the network server’s buffer memory, the probability of packet loss from the incoming self-similar traffic parameters, and reveal the possibilities of traffic modelling in the MATLAB system.
9
Al mojamed, Mohammad. "On the Use of LoRaWAN for Mobile Internet of Things: The Impact of Mobility." Applied System Innovation 5, no. 1 (December 24, 2021): 5. http://dx.doi.org/10.3390/asi5010005.
Повний текст джерелаАнотація:
A long-range wide-area network (LoRaWAN) targets both mobile and static Internet of Things (IoT) applications; it is suited to IoT applications, which require a large coverage area while consuming less power at a low data rate; it provides a solution for transferring data between IoT devices with a minimum cost in terms of power, at the expense of higher latency. LoRaWAN was designed for static low-power long-range networks. However, several IoT solution applications involve the use of mobility. Therefore, this study investigates the usage of LoRaWAN in the field of mobile Internet of Things applications such as bike rentals, fleet monitoring, and wildlife and animal tracking applications. Using the OMNeT++ simulator, two different well-known mobility models are used to investigate the influence of mobility on the performance of mobile LoRaWAN. The results show that intense LoRaWAN networks can operate under a high velocity and varying traffic load. It can be observed that the random waypoint model combination yields a better performance, but at the cost of higher collisions and energy consumption. As a consequence, the results suggest the reconsideration of mobile IoT solutions over LoRaWAN.
10
Maudet, Sébastien, Guillaume Andrieux, Romain Chevillon, and Jean-François Diouris. "Refined Node Energy Consumption Modeling in a LoRaWAN Network." Sensors 21, no. 19 (September 25, 2021): 6398. http://dx.doi.org/10.3390/s21196398.
Повний текст джерелаАнотація:
LPWAN technologies such as LoRa are widely used for the deployment of IoT applications, in particular for use cases requiring wide coverage and low energy consumption. To minimize the maintenance cost, which can become significant when the number of sensors deployed is large, it is essential to optimize the lifetime of nodes, which remains an important research topic. For this reason, it is necessary that it is based on a fine energy consumption model. Unfortunately, many existing consumption models do not take into account the specifications of the LoRaWAN protocol. In this paper, a refined energy consumption model based on in-situ measurements is provided for a LoRaWAN node. This improved model takes into account the number of nodes in the network, the collision probability that depends on the density of sensors, and the number of retransmissions. Results show the influence of the number of nodes in a LoRaWAN network on the energy consumption of a node and demonstrate that the number of sensors that can be integrated into a LoRaWAN network is limited due to the probability of collision.
11
Hosseinzadeh, Salaheddin, Hadi Larijani, Krystyna Curtis, and Andrew Wixted. "An Adaptive Neuro-Fuzzy Propagation Model for LoRaWAN." Applied System Innovation 2, no. 1 (March 18, 2019): 10. http://dx.doi.org/10.3390/asi2010010.
Повний текст джерелаАнотація:
This article proposes an adaptive-network-based fuzzy inference system (ANFIS) model for accurate estimation of signal propagation using LoRaWAN. By using ANFIS, the basic knowledge of propagation is embedded into the proposed model. This reduces the training complexity of artificial neural network (ANN)-based models. Therefore, the size of the training dataset is reduced by 70% compared to an ANN model. The proposed model consists of an efficient clustering method to identify the optimum number of the fuzzy nodes to avoid overfitting, and a hybrid training algorithm to train and optimize the ANFIS parameters. Finally, the proposed model is benchmarked with extensive practical data, where superior accuracy is achieved compared to deterministic models, and better generalization is attained compared to ANN models. The proposed model outperforms the nondeterministic models in terms of accuracy, has the flexibility to account for new modeling parameters, is easier to use as it does not require a model for propagation environment, is resistant to data collection inaccuracies and uncertain environmental information, has excellent generalization capability, and features a knowledge-based implementation that alleviates the training process. This work will facilitate network planning and propagation prediction in complex scenarios.
12
Mtetwa, Njabulo Sakhile, Paul Tarwireyi, Cecilia Nombuso Sibeko, Adnan Abu-Mahfouz, and Matthew Adigun. "Blockchain-Based Security Model for LoRaWAN Firmware Updates." Journal of Sensor and Actuator Networks 11, no. 1 (January 7, 2022): 5. http://dx.doi.org/10.3390/jsan11010005.
Повний текст джерелаАнотація:
The Internet of Things (IoT) is changing the way consumers, businesses, and governments interact with the physical and cyber worlds. More often than not, IoT devices are designed for specific functional requirements or use cases without paying too much attention to security. Consequently, attackers usually compromise IoT devices with lax security to retrieve sensitive information such as encryption keys, user passwords, and sensitive URLs. Moreover, expanding IoT use cases and the exponential growth in connected smart devices significantly widen the attack surface. Despite efforts to deal with security problems, the security of IoT devices and the privacy of the data they collect and process are still areas of concern in research. Whenever vulnerabilities are discovered, device manufacturers are expected to release patches or new firmware to fix the vulnerabilities. There is a need to prioritize firmware attacks, because they enable the most high-impact threats that go beyond what is possible with traditional attacks. In IoT, delivering and deploying new firmware securely to affected devices remains a challenge. This study aims to develop a security model that employs Blockchain and the InterPlanentary File System (IPFS) to secure firmware transmission over a low data rate, constrained Long-Range Wide Area Network (LoRaWAN). The proposed security model ensures integrity, confidentiality, availability, and authentication and focuses on resource-constrained low-powered devices. To demonstrate the utility and applicability of the proposed model, a proof of concept was implemented and evaluated using low-powered devices. The experimental results show that the proposed model is feasible for constrained and low-powered LoRaWAN devices.
13
Lin, Jun, Zhiqi Shen, Chunyan Miao, and Siyuan Liu. "Using blockchain to build trusted LoRaWAN sharing server." International Journal of Crowd Science 1, no. 3 (September 4, 2017): 270–80. http://dx.doi.org/10.1108/ijcs-08-2017-0010.
Повний текст джерелаАнотація:
Purpose With the rapid growth of the Internet of Things (IoT) market and requirement, low power wide area (LPWA) technologies have become popular. In various LPWA technologies, Narrow Band IoT (NB-IoT) and long range (LoRa) are two main leading competitive technologies. Compared with NB-IoT networks, which are mainly built and managed by mobile network operators, LoRa wide area networks (LoRaWAN) are mainly operated by private companies or organizations, which suggests two issues: trust of the private network operators and lack of network coverage. This study aims to propose a conceptual architecture design of a blockchain built-in solution for LoRaWAN network servers to solve these two issues for LoRaWAN IoT solution. Design/methodology/approach The study proposed modeling, model analysis and architecture design. Findings The proposed solution uses the blockchain technology to build an open, trusted, decentralized and tamper-proof system, which provides the indisputable mechanism to verify that the data of a transaction has existed at a specific time in the network. Originality/value To the best of our knowledge, this is the first work that integrates blockchain technology and LoRaWAN IoT technology.
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Nashiruddin, Muhammad Imam, Maruli Tua Baja Sihotang, and Muhammad Ary Murti. "Comparative study of low power wide area network based on internet of things for smart city deployment in Bandung city." Indonesian Journal of Electrical Engineering and Computer Science 25, no. 1 (January 1, 2022): 425. http://dx.doi.org/10.11591/ijeecs.v25.i1.pp425-439.
Повний текст джерелаАнотація:
Smart city implementation, such as smart energy and utilities, smart mobility & transportation, smart environment, and smart living in urban areas is expanding rapidly worldwide. However, one of the biggest challenges that need to be solved is the selection of the appropriate internet of things (IoT) connectivity technologies. This research will seek for the best candidate low power wide area network (LPWAN) technologies such as long-range wide area network (LoRaWAN), narrow-band internet of things (NB-IoT), and random phase multiple access (RPMA) for IoT smart city deployment in Bandung city is based on IoT network connectivity between with six technical evaluation criteria: gateway requirements, traffic/data projection, the best signal level area distribution, and overlapping zones. Bass model is carried out to determine the capacity forecast. While in coverage prediction, LoRaWAN and NB-IoT use the Okumura-Hata propagation, and Erceg-Greenstein (SUI) model is used for RPMA. Based on the simulation and performance evaluation results, RPMA outperforms LoRaWAN and NB-IoT. It required the least gateway number to cover Bandung city with the best signal levels and overlapping zones.
15
Chinchilla-Romero, Natalia, Jorge Navarro-Ortiz, Pablo Muñoz, and Pablo Ameigeiras. "Collision Avoidance Resource Allocation for LoRaWAN." Sensors 21, no. 4 (February 9, 2021): 1218. http://dx.doi.org/10.3390/s21041218.
Повний текст джерелаАнотація:
The number of connected IoT devices is significantly increasing and it is expected to reach more than two dozens of billions of IoT connections in the coming years. Low Power Wide Area Networks (LPWAN) have become very relevant for this new paradigm due to features such as large coverage and low power consumption. One of the most appealing technologies among these networks is LoRaWAN. Although it may be considered as one of the most mature LPWAN platforms, there are still open gaps such as its capacity limitations. For this reason, this work proposes a collision avoidance resource allocation algorithm named the Collision Avoidance Resource Allocation (CARA) algorithm with the objective of significantly increase system capacity. CARA leverages the multichannel structure and the orthogonality of spreading factors in LoRaWAN networks to avoid collisions among devices. Simulation results show that, assuming ideal radio link conditions, our proposal outperforms in 95.2% the capacity of a standard LoRaWAN network and increases the capacity by almost 40% assuming a realistic propagation model. In addition, it has been verified that CARA devices can coexist with LoRaWAN traditional devices, thus allowing the simultaneous transmissions of both types of devices. Moreover, a proof-of-concept has been implemented using commercial equipment in order to check the feasibility and the correct operation of our solution.
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Wu, Yin, Genwei Guo, Guiyun Tian, and Wenbo Liu. "A Model with Leaf Area Index and Trunk Diameter for LoRaWAN Radio Propagation in Eastern China Mixed Forest." Journal of Sensors 2020 (June 22, 2020): 1–16. http://dx.doi.org/10.1155/2020/2687148.
Повний текст джерелаАнотація:
Internet of Things (IoT) is a very promising technology in forest engineering, especially for the environment and plant growth monitoring. LoRa Wide Area Network (LoRaWAN) is a prevailing choice for the Forestry IoT owing to its low-power and long-range ability. Real-world deployment and network optimization require accurate path-loss modeling, so the LoRaWAN radio channel in the forest is needed to be intensively studied. However, most of the subsistent propagation models do not involve specific forestry environmental parameters. In this paper, two parameters related with the trees are considered: the leaf area index and the tree trunk diameter. Due to the time-changing characteristics of these two items (from spring to winter), an empirical model has been developed through extensive measurement campaigns: Firstly, the channel measurement platform is designed based on a real scene of mixed forest. Secondly, the fading characteristics of the channel transmission for LoRa nodes are tested, and the corresponding model is presented and evaluated. Lastly, an energy harvesting LoRaWAN is deployed and operated in a sampled forest region of Eastern China for environment monitoring based on our propagation model. The results show that 433 MHz LoRa path loss in the mingled forest could be precisely predicted by our proposed model. Moreover, network coverage and energy consumption optimization of the LoRa nodes could be performed, which enables the perpetual development of reliable forestry evolution monitoring system.
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Jung, Ji-Young, and Jung-Ryun Lee. "Throughput and Packet Loss Probability Analysis of Long Range Wide Area Network." Applied Sciences 11, no. 17 (August 31, 2021): 8091. http://dx.doi.org/10.3390/app11178091.
Повний текст джерелаАнотація:
Long Range Wide Area Network (LoRaWAN) is the one of the promising low power wide area network (LPWAN) technologies at present and is expected to grow in the foreseeable future as a tool to provide connectivity among small things. In this paper, we present a simple analytical model to compute the throughput and packet loss probability of Medium Access Control (MAC) for Class-A of LoRaWAN. This analysis results can be used as a reference for deploying the appropriate number of end-devices (EDs) that can be accepted in a gateway (GW) while maximizing network throughput or guaranteeing the packet loss rate of EDs.
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Farhad, Arshad, Dae-Ho Kim, and Jae-Young Pyun. "Resource Allocation to Massive Internet of Things in LoRaWANs." Sensors 20, no. 9 (May 6, 2020): 2645. http://dx.doi.org/10.3390/s20092645.
Повний текст джерелаАнотація:
A long-range wide area network (LoRaWAN) adapts the ALOHA network concept for channel access, resulting in packet collisions caused by intra- and inter-spreading factor (SF) interference. This leads to a high packet loss ratio. In LoRaWAN, each end device (ED) increments the SF after every two consecutive failed retransmissions, thus forcing the EDs to use a high SF. When numerous EDs switch to the highest SF, the network loses its advantage of orthogonality. Thus, the collision probability of the ED packets increases drastically. In this study, we propose two SF allocation schemes to enhance the packet success ratio by lowering the impact of interference. The first scheme, called the channel-adaptive SF recovery algorithm, increments or decrements the SF based on the retransmission of the ED packets, indicating the channel status in the network. The second approach allocates SF to EDs based on ED sensitivity during the initial deployment. These schemes are validated through extensive simulations by considering the channel interference in both confirmed and unconfirmed modes of LoRaWAN. Through simulation results, we show that the SFs have been adaptively applied to each ED, and the proposed schemes enhance the packet success delivery ratio as compared to the typical SF allocation schemes.
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Bouguera, Taoufik, Jean-François Diouris, Jean-Jacques Chaillout, Randa Jaouadi, and Guillaume Andrieux. "Energy Consumption Model for Sensor Nodes Based on LoRa and LoRaWAN." Sensors 18, no. 7 (June 30, 2018): 2104. http://dx.doi.org/10.3390/s18072104.
Повний текст джерела
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Behjati, Mehran, Aishah Binti Mohd Noh, Haider A. H. Alobaidy, Muhammad Aidiel Zulkifley, Rosdiadee Nordin, and Nor Fadzilah Abdullah. "LoRa Communications as an Enabler for Internet of Drones towards Large-Scale Livestock Monitoring in Rural Farms." Sensors 21, no. 15 (July 26, 2021): 5044. http://dx.doi.org/10.3390/s21155044.
Повний текст джерелаАнотація:
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).
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Tsakmakis, Athanasios, Anastasios Valkanis, Georgia Beletsioti, Konstantinos Kantelis, Petros Nicopolitidis, and Georgios Papadimitriou. "An Adaptive LoRaWAN MAC Protocol for Event Detection Applications." Sensors 22, no. 9 (May 6, 2022): 3538. http://dx.doi.org/10.3390/s22093538.
Повний текст джерелаАнотація:
In recent years, the Internet of Things (IoT) is growing rapidly and gaining ground in a variety of fields. Such fields are environmental disasters, such as forest fires, that are becoming more common because of the environmental crisis and there is a need to properly manage them. Therefore, utilizing IoT for event detection and monitoring is an effective solution. A technique for monitoring such events over a large area is proposed in this research. This work makes use of the Long-Range Wide Area Network (LoRaWAN) protocol, which is capable to connect low-power devices distributed on large geographical areas. A learning-automata-based hybrid MAC model is suggested to reduce the transmission delay, when a small part of the network produces event packets stemming from an event occurrence that is related to environmental monitoring applications, such as events related to forest fires. The proposed hybrid MAC is evaluated via simulation, which indicates that it achieves significantly higher performance in terms of packet delay, when compared to traditional LoRaWAN schemes.
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Paul, Biswajit. "A Novel Mathematical Model to Evaluate the Impact of Packet Retransmissions in LoRaWAN." IEEE Sensors Letters 4, no. 5 (May 2020): 1–4. http://dx.doi.org/10.1109/lsens.2020.2986794.
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Muñoz, Rodrigo, Juan Saez Hidalgo, Felipe Canales, Diego Dujovne, and Sandra Céspedes. "SCHC over LoRaWAN Efficiency: Evaluation and Experimental Performance of Packet Fragmentation." Sensors 22, no. 4 (February 16, 2022): 1531. http://dx.doi.org/10.3390/s22041531.
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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.
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Тунеголовец, Д. К. "ASSESSMENT OF THE APPLICABILITY OF LARAWAN TECHNOLOGIES FOR THE ORGANIZATION OF A BACKUP COMMUNICATION CHANNEL FOR METEOROLOGICAL SUPPORT OF AIRFIELDS." ВЕСТНИК ВОРОНЕЖСКОГО ГОСУДАРСТВЕННОГО ТЕХНИЧЕСКОГО УНИВЕРСИТЕТА, no. 5 (November 19, 2021): 25–31. http://dx.doi.org/10.36622/vstu.2021.15.5.004.
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В настоящее время информация о состоянии атмосферы широко используется как при составлении прогнозов погоды, так и при решении многих экономических задач. Существенная особенность метеорологических явлений - их пространственно-временная изменчивость. Это вызывает необходимость такой организации наблюдений, которая позволит своевременно отметить возникновение явления и проследить за ходом его развития. Статистика показывает, что в период с 1997 по 2000 годы произошло порядка 193 авиационных инцидентoв, которые обусловлены недостатками метеорологического обеспечения полетов. Поэтому задача повышения качества метеорологического обеспечения является актуальной. На основе модельных и практических экспериментов показано, что беспроводной канал связи LoRaWaN способен объединить весь поток данных, поступающих с удаленных метеорологических датчиков, которые используют разные протоколы для взаимодействия друг с другом. В ходе выполнения эксперимента получены положительные результаты, доказывающие возможность организации таких каналов связи для задач метеообеспечения аэродромов. Также приводится структурная схема для организации канала связи. При этом не требуется прокладка кабельных коммуникаций связи, когда стоимость такого вида работ, включая согласование, зачастую значительно превышает стоимость самого метеорологического оборудования At present, information on the state of the atmosphere is widely used both in the preparation of weather forecasts and in solving many economic problems. An essential feature of meteorological phenomena is their spatial and temporal variability. This makes it necessary to organize observations in such a way that will allow timely noting the occurrence of the phenomenon and monitoring the progress of its development. Statistics show that in the period from 1997 to 2000 there were about 193 aviation incidents, which were caused by shortcomings in the meteorological support of flights. Therefore, the task of improving the quality of meteorological support is urgent. This article shows, based on model and practical experiments, that the LaRaWAN wireless communication channel is able to combine the entire data stream coming from remote meteorological sensors using various communication protocols among themselves. During the experiment, I obtained positive results, proving the possibility of organizing such communication channels for the tasks of meteorological support of airfields. A block diagram for the organization of a communication channel is also provided. At the same time, the laying of cable communications is not required, when the cost of this type of work, including coordination, often significantly exceeds the cost of the meteorological equipment itself
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Todoli-Ferrandis, David, Javier Silvestre-Blanes, and Víctor Sempere-Payá. "Robust Downlink Mechanism for Industrial Internet of Things Using LoRaWAN Networks." Electronics 10, no. 17 (August 31, 2021): 2122. http://dx.doi.org/10.3390/electronics10172122.
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The adoption of LoRaWAN as a technology for wireless deployments in many applications, such as smart cities or industry 4.0, still presents challenges such as energy consumption, robustness, or reduced throughput in harsh, noisy scenarios. Class B is a MAC mode that allows better performance in downlink traffic but has difficulties regarding scalability and its response to channel interference. This article introduces, via simulation software, the possibility of testing deployments, adding interference sources that model industrial scenarios, and proposes an adaptive data rate (ADR) mechanism to enhance the operation for downlink and class B devices, called DROB (downlink rate optimization for class B) to study the impact of these conditions in a network with detailed event characterization.
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Hosseinzadeh, Salaheddin, Mahmood Almoathen, Hadi Larijani, and Krystyna Curtis. "A Neural Network Propagation Model for LoRaWAN and Critical Analysis with Real-World Measurements." Big Data and Cognitive Computing 1, no. 1 (December 14, 2017): 7. http://dx.doi.org/10.3390/bdcc1010007.
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Pasetti, Marco, Paolo Ferrari, Diego Rodrigo Cabral Silva, Ivanovitch Silva, and Emiliano Sisinni. "On the Use of LoRaWAN for the Monitoring and Control of Distributed Energy Resources in a Smart Campus." Applied Sciences 10, no. 1 (January 1, 2020): 320. http://dx.doi.org/10.3390/app10010320.
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The application of the most recent advances of the Internet-of-Things (IoT) technology to the automation of buildings is emerging as a promising solution to achieve greater efficiencies in energy consumption, and to allow the realization of sustainable models. The application of IoT has been demonstrated as effective in many fields, such as confirmed, for instance, by the Industry 4.0 concepts, which are revolutionizing modern production chains. By following this approach, the use of distributed control architectures and of IoT technologies (both wired and wireless) would result in effective solutions for the management of smart environments composed of groups of buildings, such as campuses. In this case, heterogeneous IoT solutions are typically adopted to satisfy the requirements of the very diverse possible scenarios (e.g., indoor versus outdoor coverage, mobile versus fixed nodes, just to mention a few), making their large-scale integration cumbersome. To cope with this issue, this paper presents an IoT architecture able to transparently manage different communication protocols in smart environments, and investigates its possible application for the monitoring and control of distributed energy resources in a smart campus. In particular, a use–case focused on the integration of the Long Range Wide Area Network (LoRaWAN) technology is considered to cope with heterogeneous indoor and outdoor communication scenarios. The feasibility analysis of the proposed solution is carried out by computing the scalability limits of the approach, based on the proposed smart campus data model. The results of the study showed that the proposed solution would be able to manage more than 10,000 nodes. An experimental validation of the LoRaWAN technology confirms its suitability in terms of coverage and latency, with a minimum LoRaWAN cell coverage range of 250 m, and a communication latency of about 400 ms. Finally, the advantages of the proposed solution in the supervision and management of a PV system are highlighted in a real-world scenario.
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Xu, Wu Nong, and Fen Liu. "The Measurement and Time Series Analysis of Loran C Ground Wave Propagation Delay." Advanced Materials Research 457-458 (January 2012): 74–78. http://dx.doi.org/10.4028/www.scientific.net/amr.457-458.74.
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In order to effectively correct the positioning error of Loran C to improve the positioning accuracy, it is necessary to study Loran C ground wave signal propagation delay variation with time, study the stability of propagation delay and timing characteristics. Take statistical analysis and pretreatment to Loran C ground wave signal propagation delay, test its stationarity, extraction its trend term, obtain stationary series, modeling to trend term and stationary series. The results show that Loran C ground wave signal propagation delay has good stability and repeatability, the time delay series can be fitted to combination model formed by G (2,1) cycle model and AR (p) from the regression model.
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Šafář, Jan, Paul Williams, and František Vejražka. "Accuracy Performance Of E-Loran Receivers Under Cross-Rate Interference Conditions." Annual of Navigation 19, no. 1 (November 1, 2012): 133–48. http://dx.doi.org/10.2478/v10367-012-0011-y.
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Abstract According to a recent Business Case produced by the General Lighthouse Authorities of the United Kingdom and Ireland (GLAs), e-Loran is the only system that, when combined with GNSS, can achieve cost effective resilient Positioning, Navigation and Timing (PNT) by 2018 for maritime e-Navigation. The GLAs currently operate a trial e-Loran service from Harwich, UK and are working towards establishing e-Loran Initial Operational Capability (IOC) in the seven busiest UK ports and port approaches by mid-2013. A future extension of e-Loran coverage to the entire GLA service area will require the installation of additional transmitting stations. When planning the installation of e-Loran transmitters service providers will need a good understanding of the effects of the new signals on the system’s performance. Since all e-Loran stations share the same frequency band and the e-Loran signals propagate over vast distances, special attention needs to be paid to the issue of intra-system interference. This is also referred to as Cross-Rate Interference (CRI) and is inherent to the way e-Loran operates. In this paper we examine the impact of CRI on the position accuracy performance of e-Loran receivers. First, a signal processing model for a typical e-Loran receiver is developed. This could provide the e-Loran community with a unified framework for receiver performance evaluation. Numerical and, where possible, analytical results obtained from the model are then presented, describing the achievable accuracy performance under different interference conditions. The theoretical results are also compared to those obtained from measurements made on a commercially available receiver driven by a signal simulator. Our analysis shows that modern e-Loran signal processing algorithms can achieve a substantial reduction of the negative effects of CRI. However, there is still an appreciable residual effect, which should be taken into account when designing future e-Loran networks and determining their coverage and performance
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Arshad, Jehangir, Musharraf Aziz, Asma A. Al-Huqail, Muhammad Hussnain uz Zaman, Muhammad Husnain, Ateeq Ur Rehman, and Muhammad Shafiq. "Implementation of a LoRaWAN Based Smart Agriculture Decision Support System for Optimum Crop Yield." Sustainability 14, no. 2 (January 12, 2022): 827. http://dx.doi.org/10.3390/su14020827.
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A majority of the population of developing countries is associated with agriculture directly or indirectly. The liaison of engineering technology and Sustainable Development Goals (SDGs) can build a bridge for farmers to enhance their skills regarding advancements through future generation agriculture trends. The next-generation trends include better soil preparation, intelligent irrigation systems, advanced methods of crop nutrient inspection, smart fertilizers applications, and multi-cropping practices. This work proposes a smart Decision Support System (DSS) that acquires the input parameters based on real-time monitoring to optimize the yield that realizes sustainability by improving per hectare production and lessening water seepage wastage in agribusiness. The proposed model comprises three basic units including an intelligent sensor module, smart irrigation system and controlled fertilizer module. The system has integrated sensors, cloud employing decision support layers, and networking based DSS to recommend cautions for optimum sustainable yield. The intelligent sensors module contains a temperature and humidity sensor, NPK sensor, soil moisture sensor, soil conductivity sensor, and pH sensor to transmit the statistics to the cloud over the internet via Long Range (LoRa) using Serial Peripheral Interface (SPI) communication protocol. Moreover, an android application has been developed for real-time data monitoring according to GPS location and node information (accessed remotely). Furthermore, the DSS contemplates the accessible information from sensors, past patterns, monitoring climate trends and creating cautions required for sustainable fertilizer consumption. The presented results and comparison validate the novelty of the design as it embraces smart irrigation with smart control and smart decision-making based on accurate real-time field data. It is better than existing systems as it transmits the data over the LoRa that is an open-source communication with long-range transmission ability up to several kilometres. The sensor nodes helped in advancing the yield of crops, which resulted in achieving inclusive and sustainable economic goals.
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Mouapi, Alex, Nadir Hakem, and Nahi Kandil. "Piezoelectric Energy Harvesting Prediction and Efficient Management for Industrial Wireless Sensor." Applied Sciences 10, no. 23 (November 27, 2020): 8486. http://dx.doi.org/10.3390/app10238486.
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The vibrations, due to their abundance in most industrial processes, constitute an attractive solution for the power supply of Industrial Wireless Sensor (IWS). However, the amount of energy that can be harvested presents numerous fluctuations due to the engines’ different operating modes (overload, full load, or even operation without charge). Most designs do not incorporate this fluctuation in the definition of the specifications of the autonomous IWS. This paper then presents a design method to ensure the node’s energy autonomy while maximizing its Quality of Service (QoS). To precisely define the specifications of the IWS, vibration measurements were carried out at its location for one month. The recorded data was used to propose a new Predictor of the Harvestable Energy from Vibrations (PHEV). A comparative evaluation of the proposed PHEV performances with a state-of-the-art predictor is carried out. The results obtained show that the PHEV makes it possible to minimize the Root Mean Square Error (RMSE) from 28.63 mW to 19.52 mW. A model of energy dissipation in IWS, considering the Internet of Things’ requirements, was established. The model is based on Long-Range (LoRa)/Long-Range Communication Wide Area Network (LoRaWan). The amount of data transmitted is then maximized according to the expected energy harvest rate by setting up a Maximization Data Size Protocol (MDSP). The proposed method makes it possible to ensure an acceptable QoS without resorting to reconfigurable circuits, which are sometimes bulky for miniature devices such as the IWS.
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Rezvani, Sayed Moin-eddin, Hamid Zare Abyaneh, Redmond R. Shamshiri, Siva K. Balasundram, Volker Dworak, Mohsen Goodarzi, Muhammad Sultan, and Benjamin Mahns. "IoT-Based Sensor Data Fusion for Determining Optimality Degrees of Microclimate Parameters in Commercial Greenhouse Production of Tomato." Sensors 20, no. 22 (November 12, 2020): 6474. http://dx.doi.org/10.3390/s20226474.
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Optimum microclimate parameters, including air temperature (T), relative humidity (RH) and vapor pressure deficit (VPD) that are uniformly distributed inside greenhouse crop production systems are essential to prevent yield loss and fruit quality. The objective of this research was to determine the spatial and temporal variations in the microclimate data of a commercial greenhouse with tomato plants located in the mid-west of Iran. For this purpose, wireless sensor data fusion was incorporated with a membership function model called Optimality Degree (OptDeg) for real-time monitoring and dynamic assessment of T, RH and VPD in different light conditions and growth stages of tomato. This approach allows growers to have a simultaneous projection of raw data into a normalized index between 0 and 1. Custom-built hardware and software based on the concept of the Internet-of-Things, including Low-Power Wide-Area Network (LoRaWAN) transmitter nodes, a multi-channel LoRaWAN gateway and a web-based data monitoring dashboard were used for data collection, data processing and monitoring. The experimental approach consisted of the collection of meteorological data from the external environment by means of a weather station and via a grid of 20 wireless sensor nodes distributed in two horizontal planes at two different heights inside the greenhouse. Offline data processing for sensors calibration and model validation was carried in multiple MATLAB Simulink blocks. Preliminary results revealed a significant deviation of the microclimate parameters from optimal growth conditions for tomato cultivation due to the inaccurate timer-based heating and cooling control systems used in the greenhouse. The mean OptDeg of T, RH and VPD were 0.67, 0.94, 0.94 in January, 0.45, 0.36, 0.42 in June and 0.44, 0.0, 0.12 in July, respectively. An in-depth analysis of data revealed that averaged OptDeg values, as well as their spatial variations in the horizontal profile were closer to the plants’ comfort zone in the cold season as compared with those in the warm season. This was attributed to the use of heating systems in the cold season and the lack of automated cooling devices in the warm season. This study confirmed the applicability of using IoT sensors for real-time model-based assessment of greenhouse microclimate on a commercial scale. The presented IoT sensor node and the Simulink model provide growers with a better insight into interpreting crop growth environment. The outcome of this research contributes to the improvement of closed-field cultivation of tomato by providing an integrated decision-making framework that explores microclimate variation at different growth stages in the production season.
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Monin, A. "Submarine floating antenna model for LORAN-C signal processing." IEEE Transactions on Aerospace and Electronic Systems 39, no. 4 (October 2003): 1304–15. http://dx.doi.org/10.1109/taes.2003.1261130.
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Mukhamejanova, А. D., K. Kh Tumanbayeva, E. M. Lechshinskaya, and B. Ongar. "STATISTICAL ANALYSIS OF REAL TRAFFIC OF MACHINE-TO-MACHINE COMMUNICATION (M2M)." Series of Geology and Technical Sciences 2, no. 446 (April 15, 2021): 107–13. http://dx.doi.org/10.32014/2021.2518-170x.41.
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The development of digital technology has spawned the concept of the Internet of Things (IoT). The concept basis is the machine-to-machine interaction (M2M) technology, which allows devices to exchange information. The most effective data transmission medium for M2M devices is mobile communications. Rapid growth of machine-to-machine М2М traffic in mobile communication network defines the actuality of the research problem, its features and characteristics. Research outcomes are indispensable at the network modeling, planning, analyzing the М2М traffic impact at quality of service (QoS) of mobile network communication. The article analyzes the real traffic in the LoraWan network. Aggregated traffic coming to the network server from all devices is considered. To model the М2М batch traffic, apart from specifying the statistic characteristics it is necessary to assess its self-similarity. In order to define the traffic self-similarity there has been computed Hurst parameter. On the basis of STATISTICA programs batch we have conducted statistical analysis and short-term forecasting of real М2М traffic by method of exponential smoothing.
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Aburukba, Raafat, A. R. Al-Ali, Ahmed H. Riaz, Ahmad Al Nabulsi, Danayal Khan, Shavaiz Khan, and Moustafa Amer. "Fog Computing Approach for Shared Mobility in Smart Cities." Energies 14, no. 23 (December 6, 2021): 8174. http://dx.doi.org/10.3390/en14238174.
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Smart transportation a smart city application where traditional individual models are transforming to shared and distributed ownership. These models are used to serve commuters for inter- and intra-city travel. However, short-range urban transportation services within campuses, residential compounds, and public parks are not explored to their full capacity compared to the distributed vehicle model. This paper aims to explore and design an adequate framework for battery-operated shared mobility within a large community for short-range travel. This work identifies the characteristics of the shared mobility for battery-operated vehicles and accordingly proposes an adequate solution that deals with real-time data collection, tracking, and automated decisions. Furthermore, given the requirement for real-time decisions with low latency for critical requests, the paper deploys the proposed framework within the 3-tier computing model, namely edge, fog, and cloud tiers. The solution design considers the power consumption requirement at the edge by offloading the computational requests to the fog tier and utilizing the LoRaWAN communication technology. A prototype implementation is presented to validate the proposed framework for a university campus using e-bikes. The results show the scalability of the proposed design and the achievement of low latency for requests that require real-time decisions.
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Ould, Solomon, and Nick S. Bennett. "Energy Performance Analysis and Modelling of LoRa Prototyping Boards." Sensors 21, no. 23 (November 30, 2021): 7992. http://dx.doi.org/10.3390/s21237992.
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LoRaWAN has gained significant attention for Internet-of-Things (IOT) applications due to its low power consumption and long range potential for data transmission. While there is a significant body of work assessing LoRA coverage and data transmission characteristics, there is a lack of data available about commercially available LoRa prototyping boards and their power consumption, in relation to their features. It is currently difficult to estimate the power consumption of a LoRa module operating under different transmission profiles, due to a lack of manufacturer data available. In this study, power testing has been carried out on physical hardware and significant variation was found in the power consumption of competing boards, all marketed as “extremely low power”. In this paper, testing results are presented alongside an experimentally-derived power model for the lowest power LoRa module, and power requirements are compared to firmware settings. The power analysis adds to existing work showing trends in data-rate and transmission power settings effects on electrical power consumption. The model’s accuracy is experimentally verified and shows acceptable agreement to estimated values. Finally, applications for the model are presented by way of a hypothetical scenario and calculations performed in order to estimate battery life and energy consumption for varying data transmission intervals.
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Casadei, Roberto, Danilo Pianini, Andrea Placuzzi, Mirko Viroli, and Danny Weyns. "Pulverization in Cyber-Physical Systems: Engineering the Self-Organizing Logic Separated from Deployment." Future Internet 12, no. 11 (November 19, 2020): 203. http://dx.doi.org/10.3390/fi12110203.
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Emerging cyber-physical systems, such as robot swarms, crowds of augmented people, and smart cities, require well-crafted self-organizing behavior to properly deal with dynamic environments and pervasive disturbances. However, the infrastructures providing networking and computing services to support these systems are becoming increasingly complex, layered and heterogeneous—consider the case of the edge–fog–cloud interplay. This typically hinders the application of self-organizing mechanisms and patterns, which are often designed to work on flat networks. To promote reuse of behavior and flexibility in infrastructure exploitation, we argue that self-organizing logic should be largely independent of the specific application deployment. We show that this separation of concerns can be achieved through a proposed “pulverization approach”: the global system behavior of application services gets broken into smaller computational pieces that are continuously executed across the available hosts. This model can then be instantiated in the aggregate computing framework, whereby self-organizing behavior is specified compositionally. We showcase how the proposed approach enables expressing the application logic of a self-organizing cyber-physical system in a deployment-independent fashion, and simulate its deployment on multiple heterogeneous infrastructures that include cloud, edge, and LoRaWAN network elements.
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Centelles, Roger Pueyo, Felix Freitag, Roc Meseguer, Leandro Navarro, Sergio F. Ochoa, and Rodrigo M. Santos. "A LoRa-Based Communication System for Coordinated Response in an Earthquake Aftermath." Proceedings 31, no. 1 (November 21, 2019): 73. http://dx.doi.org/10.3390/proceedings2019031073.
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The response conducted by emergency units after natural disasters, such as earthquakes, has to be coordinated, fast, and efficient in order to rescue and care for the victims, keeping all the population—and the units themselves—safe amidst the usual chaos. Outages in wireless networks, as well as fiber- or copper-based landline and Internet connections, are to be expected in these situations, so alternative communication solutions must be considered. To contribute in this duty, we propose a communication system that uses the LoRaWAN architecture to allow citizens to report their status to emergency units and public authorities with simple messages and interaction mechanisms. The purpose of this system is to keep people and first responders connected, and thus improve the capability to coordinate the evacuation activities. To analyze the system performance and capabilities, we model a district of Coquimbo, a harbor town in Chile that houses approximately 28,000 people in 7500 homes, and simulate it with a baseline configuration. We explore several settings for the system in order to determine its characteristics and limitations, to better understand its scalability and portability to other environments, and to outline the remaining challenges to make the system attain specific performance guarantees.
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Asad Ullah, Muhammad, Junnaid Iqbal, Arliones Hoeller, Richard Souza, and Hirley Alves. "K-Means Spreading Factor Allocation for Large-Scale LoRa Networks." Sensors 19, no. 21 (October 30, 2019): 4723. http://dx.doi.org/10.3390/s19214723.
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Low-power wide-area networks (LPWANs) are emerging rapidly as a fundamental Internet of Things (IoT) technology because of their low-power consumption, long-range connectivity, and ability to support massive numbers of users. With its high growth rate, Long-Range (LoRa) is becoming the most adopted LPWAN technology. This research work contributes to the problem of LoRa spreading factor (SF) allocation by proposing an algorithm on the basis of K-means clustering. We assess the network performance considering the outage probabilities of a large-scale unconfirmed-mode class-A LoRa Wide Area Network (LoRaWAN) model, without retransmissions. The proposed algorithm allows for different user distribution over SFs, thus rendering SF allocation flexible. Such distribution translates into network parameters that are application dependent. Simulation results consider different network scenarios and realistic parameters to illustrate how the distance from the gateway and the number of nodes in each SF affects transmission reliability. Theoretical and simulation results show that our SF allocation approach improves the network’s average coverage probability up to 5 percentage points when compared to the baseline model. Moreover, our results show a fairer network operation where the performance difference between the best- and worst-case nodes is significantly reduced. This happens because our method seeks to equalize the usage of each SF. We show that the worst-case performance in one deployment scenario can be enhanced by 1 . 53 times.
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LO, SHERMAN C., ROBERT WENZEL, PETER MORRIS, and PER K. ENGE. "Developing and Validating the Loran Temporal ASF Bound Model for Aviation." Navigation 56, no. 1 (March 2009): 9–21. http://dx.doi.org/10.1002/j.2161-4296.2009.tb00440.x.
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Bouyedda, Abdellatif, Bruno Barelaud, and Laurent Gineste. "Design and Realization of an UHF Frequency Reconfigurable Antenna for Hybrid Connectivity LPWAN and LEO Satellite Networks." Sensors 21, no. 16 (August 13, 2021): 5466. http://dx.doi.org/10.3390/s21165466.
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UHF satellite communication for Internet of Things (IoT) technology is rapidly emerging in monitoring applications as it offers the possibility of lower-costs and global coverage. At the present time, Low Power Wide Area Network (LPWAN) solutions offer low power consumption, but still suffer from white zones. In this paper, the authors propose an UHF frequency reconfigurable Antenna for hybrid connectivity LoRaWAN (at 868 MHz) and UHF satellite communication (Tx at 401 MHz and Rx at 466 MHz) with the Low Earth Orbit (LEO) Kineis constellation. The antenna is based on a meandered line structure loaded with lumped components and a PIN diode to control the antenna resonant frequencies. It resonates at 401 and 868 MHz when the PIN diode is forward-biased (ON state) and 466 MHz in reverse-biased configuration (OFF state). The antenna is designed inside the enclosure with the presence of all the parts of the connected device. The results of EM simulations and parametric studies on the values of the lumped components and the PIN diode equivalent model, which are obtained with HFSS, are presented. The antenna is prototyped and has dimensions of 78 mm × 88 mm × 1.6 mm. The paper proposes a fast and practical method to reduce time development and compensate the frequency shift between measurement and simulation.
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Ali, Irsan Taufik, Abdul Muis, and Riri Fitri Sari. "A DEEP LEARNING MODEL IMPLEMENTATION BASED ON RSSI FINGERPRINTING FOR LORA-BASED INDOOR LOCALIZATION." EUREKA: Physics and Engineering, no. 1 (January 30, 2021): 40–59. http://dx.doi.org/10.21303/2461-4262.2021.001620.
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LoRa technology has received a lot of attention in the last few years. Numerous success stories about using LoRa technology for the Internet of Things in various implementations. Several studies have found that the use of LoRa technology has the opportunity to be implemented in indoor-based applications. LoRa technology is found more stable and is more resilient to environmental changes. Environmental change of the indoor is a major problem to maintain accuracy in position prediction, especially in the use of Received Signal Strength (RSS) fingerprints as a reference database. The variety of approaches to solving accuracy problems continues to improve as the need for indoor localization applications increases. Deep learning approaches as a solution for the use of fingerprints in indoor localization have been carried out in several studies with various novelties offered. Let’s introduce a combination of the use of LoRa technology's excellence with a deep learning method that uses all variations of measurement results of RSS values at each position as a natural feature of the indoor condition as a fingerprint. All of these features are used for training in-deep learning methods. It is DeepFi-LoRaIn which illustrates a new technique for using the fingerprint data of the LoRa device's RSS device on indoor localization using deep learning methods. This method is used to find out how accurate the model produced by the training process is to predict the position in a dynamic environment. The scenario used to evaluate the model is by giving interference to the RSS value received at each anchor node. The model produced through training was found to have good accuracy in predicting the position even in conditions of interference with several anchor nodes. Based on the test results, DeepFi-LoRaIn Technique can be a solution to cope with changing environmental conditions in indoor localization
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Chaudhari, Bharat S., Marco Zennaro, and Suresh Borkar. "LPWAN Technologies: Emerging Application Characteristics, Requirements, and Design Considerations." Future Internet 12, no. 3 (March 6, 2020): 46. http://dx.doi.org/10.3390/fi12030046.
Повний текст джерелаАнотація:
Low power wide area network (LPWAN) is a promising solution for long range and low power Internet of Things (IoT) and machine to machine (M2M) communication applications. This paper focuses on defining a systematic and powerful approach of identifying the key characteristics of such applications, translating them into explicit requirements, and then deriving the associated design considerations. LPWANs are resource-constrained networks and are primarily characterized by long battery life operation, extended coverage, high capacity, and low device and deployment costs. These characteristics translate into a key set of requirements including M2M traffic management, massive capacity, energy efficiency, low power operations, extended coverage, security, and interworking. The set of corresponding design considerations is identified in terms of two categories, desired or expected ones and enhanced ones, which reflect the wide range of characteristics associated with LPWAN-based applications. Prominent design constructs include admission and user traffic management, interference management, energy saving modes of operation, lightweight media access control (MAC) protocols, accurate location identification, security coverage techniques, and flexible software re-configurability. Topological and architectural options for interconnecting LPWAN entities are discussed. The major proprietary and standards-based LPWAN technology solutions available in the marketplace are presented. These include Sigfox, LoRaWAN, Narrowband IoT (NB-IoT), and long term evolution (LTE)-M, among others. The relevance of upcoming cellular 5G technology and its complementary relationship with LPWAN technology are also discussed.
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Galmarini, S., G. Graziani, and C. Tassone. "The atmospheric long range transport model LORAN and its application to Chernobyl release." Environmental Software 7, no. 3 (January 1992): 143–54. http://dx.doi.org/10.1016/0266-9838(92)90011-r.
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Pu, Yurong, Xiaoyi Zheng, Dandan Wang, and Xiaoli Xi. "Accuracy Improvement Model for Predicting Propagation Delay of Loran-C Signal Over a Long Distance." IEEE Antennas and Wireless Propagation Letters 20, no. 4 (April 2021): 582–86. http://dx.doi.org/10.1109/lawp.2021.3057942.
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Lyu, Boyun, Yu Hua, Jiangbin Yuan, and Shifeng Li. "Application of Ultra Narrow Band Modulation in Enhanced Loran System." Sensors 21, no. 13 (June 25, 2021): 4347. http://dx.doi.org/10.3390/s21134347.
Повний текст джерелаАнотація:
The Enhanced Loran (eLoran) system is valued for its important role in the positioning, navigation, and timing fields; however, with its current modulation methods, low data rate restricts its development. Ultra narrow band (UNB) modulation is a modulation method with extremely high spectrum utilization. If UNB modulation can be applied to the eLoran system, it will be very helpful. The extended binary phase shift keying modulation in UNB modulation is selected for a detailed study, parameters and application model are designed according to its unique characteristics of signal time and frequency domains, and it is verified through simulation that the application of this modulation not only meets the design constraints of the eLoran system but also does not affect the reception of the respective signals of both parties. Several feasible schemes are compared, analyzed, and selected. Studies have revealed that application of UNB modulation in the eLoran system is feasible, and it will increase the data rate of the system by dozens of times.
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Pointl, Michael, and Daniela Fuchs-Hanusch. "Assessing the Potential of LPWAN Communication Technologies for Near Real-Time Leak Detection in Water Distribution Systems." Sensors 21, no. 1 (January 4, 2021): 293. http://dx.doi.org/10.3390/s21010293.
Повний текст джерелаАнотація:
While low-power wide-area network (LPWAN) technologies have been studied extensively for a broad spectrum of smart city applications, their potential for water distribution system monitoring in high temporal resolution has not been studied in detail. However, due to their low power demand, these technologies offer new possibilities for operating pressure-monitoring devices for near real-time leak detection in water distribution systems (WDS). By combining long-distance wireless communication with low power consumption, LPWAN technologies promise long periods of maintenance-free device operation without having to rely on an external power source. This is of particular importance for pressure-based leak detection where optimal sensor positions are often located in the periphery of WDS without a suitable power source. To assess the potential of these technologies for replacing widely-used wireless communication technologies for leak detection, GPRS is compared with the LPWAN standards Narrowband IoT, long-range wide area network (LoRaWAN) and Sigfox. Based on sampling and transmission rates commonly applied in leak detection, the ability of these three technologies to replace GPRS is analyzed based on a self-developed low-power pressure-monitoring device and a simplified, linear energy-consumption model. The results indicate that even though some of the analyzed LPWAN technologies may suffer from contractual and technical limitations, all of them offer viable alternatives, meeting the requirements of leak detection in WDS. In accordance with existing research on data transmission with these technologies, the findings of this work show that even while retaining a compact design, which entails a limited battery capacity, pressure-monitoring devices can exceed runtimes of 5 years, as required for installation at water meters in Austria. Thus, LPWAN technologies have the potential to advance the wide application of near real-time, pressure-based leak detection in WDS, while simultaneously reducing the cost of device operation significantly.
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Awtoniuk, M., T. Nowakowski, J. Chlebowski, A. Świętochowski, M. Dąbrowska, J. Klonowski, M. Sypuła, et al. "Internet of Things as an element of the frost protection system in orchards." Journal of Physics: Conference Series 2130, no. 1 (December 1, 2021): 012015. http://dx.doi.org/10.1088/1742-6596/2130/1/012015.
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Abstract Frosts cause serious damage to fruit and vegetable crops. In Poland, temperature decreases, and the occurrence of inflow (advective) frosts most often fall during the flowering period, i.e., in a phase extremely important for the development of the plant. For orchards, this causes the inflorescences of early flowering trees (cherries, plums and certain varieties of apple and pear trees) to freeze. A modern idea for reducing frost losses in orchards is to heat the air with mobile heaters. Protection by these machines consists of passing using an agricultural tractor in rows of trees or shrubs and heating and mixing the air. The problem that farmers may encounter during frosts is the awareness of when exactly such a weather condition occurs in their orchard. Weather forecasts are not detailed and usually apply to the entire region. Dangerous temperature declines below the critical minimum can occur locally and are also conditioned by geographical location and terrain diversity. The aim of the article is to present a measuring system that allows the construction of an individualised temperature model taking into account the unique shape of the orchard surface. The system is made in Internet of Things technology using long-range radio communication protocol LoRaWAN. Data from distributed measurement sensors are processed on a network server and displayed as a final application. The task of the system is to monitor the current situation in the orchard and to notify the farmer of the need to initiate a protective procedure. The operation of the system also supports the efficient use of mobile heating machines. The system facilitates the location of the areas in the orchard with the lowest temperature, as well as provides feedback on temperature changes inside the treetops caused by the passage of the mobile heater.
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Matsakis, Demetrios. "Time and Frequency Activities at the U.S. Naval Observatory." International Journal of Navigation and Observation 2008 (July 22, 2008): 1–8. http://dx.doi.org/10.1155/2008/387418.
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The US Naval Observatory (USNO) has provided timing for the navy since 1830 and, in cooperation with other institutions, has also provided timing for the United States and the international community. Its Master Clock (MC) is the source of UTC(USNO), the USNO's realization of Coordinated Universal Time (UTC), which has stayed within 5 nanoseconds RMS of UTC since 1999. The data used to generate UTC(USNO) are based upon 73 cesium and 21 hydrogen maser frequency standards in three buildings at two sites. The USNO disseminates time via voice, telephone modem, LORAN, Network Time Protocol (NTP), GPS, and two-way satellite time transfer (TWSTT). This paper describes some of the changes being made to meet the future needs for precision, accuracy, and robustness.
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Zualkernan, Imran, Salam Dhou, Jacky Judas, Ali Reza Sajun, Brylle Ryan Gomez, and Lana Alhaj Hussain. "An IoT System Using Deep Learning to Classify Camera Trap Images on the Edge." Computers 11, no. 1 (January 13, 2022): 13. http://dx.doi.org/10.3390/computers11010013.
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Camera traps deployed in remote locations provide an effective method for ecologists to monitor and study wildlife in a non-invasive way. However, current camera traps suffer from two problems. First, the images are manually classified and counted, which is expensive. Second, due to manual coding, the results are often stale by the time they get to the ecologists. Using the Internet of Things (IoT) combined with deep learning represents a good solution for both these problems, as the images can be classified automatically, and the results immediately made available to ecologists. This paper proposes an IoT architecture that uses deep learning on edge devices to convey animal classification results to a mobile app using the LoRaWAN low-power, wide-area network. The primary goal of the proposed approach is to reduce the cost of the wildlife monitoring process for ecologists, and to provide real-time animal sightings data from the camera traps in the field. Camera trap image data consisting of 66,400 images were used to train the InceptionV3, MobileNetV2, ResNet18, EfficientNetB1, DenseNet121, and Xception neural network models. While performance of the trained models was statistically different (Kruskal–Wallis: Accuracy H(5) = 22.34, p < 0.05; F1-score H(5) = 13.82, p = 0.0168), there was only a 3% difference in the F1-score between the worst (MobileNet V2) and the best model (Xception). Moreover, the models made similar errors (Adjusted Rand Index (ARI) > 0.88 and Adjusted Mutual Information (AMU) > 0.82). Subsequently, the best model, Xception (Accuracy = 96.1%; F1-score = 0.87; F1-Score = 0.97 with oversampling), was optimized and deployed on the Raspberry Pi, Google Coral, and Nvidia Jetson edge devices using both TenorFlow Lite and TensorRT frameworks. Optimizing the models to run on edge devices reduced the average macro F1-Score to 0.7, and adversely affected the minority classes, reducing their F1-score to as low as 0.18. Upon stress testing, by processing 1000 images consecutively, Jetson Nano, running a TensorRT model, outperformed others with a latency of 0.276 s/image (s.d. = 0.002) while consuming an average current of 1665.21 mA. Raspberry Pi consumed the least average current (838.99 mA) with a ten times worse latency of 2.83 s/image (s.d. = 0.036). Nano was the only reasonable option as an edge device because it could capture most animals whose maximum speeds were below 80 km/h, including goats, lions, ostriches, etc. While the proposed architecture is viable, unbalanced data remain a challenge and the results can potentially be improved by using object detection to reduce imbalances and by exploring semi-supervised learning.