Wide Area Network Technology Research Articles

Fetal heart detection based wide area network technology with wireless sensor transmission

Fetal heart detection technology, especially in remote areas, has so far been manual and lacks facilities for monitoring fetal safety. This results in many pregnant women at risk of labor, so early detection of fetal heart conditions becomes important. Development of fetal heart detector technology based on wide area network technology that is able to provide real-time monitoring results and is connected to the proposed wireless sensor network transmission. Its integration with smartphones makes it easy to use in rural and remote areas. The design of this monitoring system called detector of fetal abnormalities technology has the advantage of sending medical data for pregnant women and fetal heart conditions to families and to health care centers for pregnant women in large cities or obstetricians. Visualization of data in image, graphic and text, can be used as a digital-based maternal and fetal health detector tool. In the initial trial, fetal heart rate data from 4 pregnant subject were evaluated and obtained results with an average curation of 94%.

Indoor Vehicles Geolocalization Using LoRaWAN

One of the main drawbacks of Global Navigation Satellite Sytems (GNSS) is that they do not work indoors. When inside, there is often no direct line from the satellite signals to the device and the ultra high frequency (UHF) used is blocked by thick, solid materials such as brick, metal, stone or wood. In this paper, we describe a solution based on the Long Range Wide Area Network (LoRaWAN) technology to geolocalise vehicles indoors. Through estimation of the behaviour of a LoRaWAN channel and using trilateration, the localisation of a vehicle can be obtained within a 20–30 m range. Indoor geolocation for Intelligent Transporation Systems (ITS) can be used to locate vehicles of any type in underground parkings, keep a platoon of trucks in formation or create geo-fences, that is, sending an alert if an object moves outside a defined area, like a bicycle being stolen. Routing of heavy vehicles within an industrial setting is another possibility.

Low-Power Wide Area Network Technologies for Internet-of-Things: A Comparative Review

The rapid growth of Internet-of-Things (IoT) in the current decade has led to the development of a multitude of new access technologies targeted at low-power, wide area networks (LP-WANs). However, this has also created another challenge pertaining to technology selection. This paper reviews the performance of LP-WAN technologies for IoT, including design choices and their implications. We consider Sigfox, LoRaWAN, WavIoT, random phase multiple access (RPMA), narrowband IoT (NB-IoT), as well as LTE-M and assess their performance in terms of signal propagation, coverage and energy conservation. The comparative analyses presented in this paper are based on available data sheets and simulation results. A sensitivity analysis is also conducted to evaluate network performance in response to variations in system design parameters. Results show that each of RPMA, NB-IoT, and LTE-M incurs at least 9 dB additional path loss relative to Sigfox and LoRaWAN. This paper further reveals that with a 10% improvement in receiver sensitivity, NB-IoT 882 MHz and LoRaWAN can increase coverage by up to 398% and 142%, respectively, without adverse effects on the energy requirements. Finally, extreme weather conditions can significantly reduce the active network life of LP-WANs. In particular, the results indicate that operating an IoT device in a temperature of -20 °C can shorten its life by about half; 53% (WavIoT, LoRaWAN, Sigfox, NB-IoT, and RPMA) and 48% in LTE-M compared with environmental temperature of 40 °C.

Gateway Channel Hopping to Improve Transmission Efficiency in Long-range IoT Networks

Intelligent services have expanded as Internet of Things (IoT) technology has evolved and new requirements emerge to accommodate various services. One new requirement is transmitting data over long distances with low-power. Researchers have developed low power wide area (LPWA) network technology to satisfy the requirement; this can improve IoT network infrastructure and increase the range of services. However, network coverage expansion causes several problems. The traffic load is concentrated at a specific gateway, which causes network congestion and leads to decreased transmission efficiency. Therefore, the approach proposed in this paper attempts to recognize and then avoid congestion through gateway channel hopping. The LPWA network employs multiple channels, so wireless channel hopping is available in a gateway. Devices that are not delay sensitive wait for the gateway to reappear on their wireless channel; delay sensitive devices change the wireless channel along the hopping gateway. Thus, the traffic load and congestion in each wireless channel can be reduced improving transmission efficiency. The proposed approach’s performance is evaluated by computer simulation and verified in terms of transmission efficiency.

Known and Unknown Facts of LoRa

Long Range (LoRa) is a Low-power Wide-area Network technology designed for the Internet of Things. In recent years, it has gained significant momentum among industrial and research communities. Patented by Semtech, LoRa makes use of chirp spread spectrum modulation to deliver data with promises of long battery life, far-reaching communication distances, and a high node density at the cost of data rate. In this article, we conduct a series of experiments to verify the claims made by Semtech on LoRa technology. Our results show that LoRa is capable of communicating over 10km under line-of-sight environments. However, under non-line-of-sight environments, LoRa’s performance is severely affected by obstructions such as buildings and vegetations. Moreover, the promise of prolonged battery life requires extreme tuning of parameters. Last, a LoRa gateway supports up to 6,000 nodes with PRR requirement of >70%. This study also explores the relationship between LoRa transmission parameters and proposes an algorithm to determine optimal settings in terms of coverage and power consumption under non-line-of-sight environments. It further investigates the impact of LoRa Wide-area Networks on energy consumption and network capacity along with implementation of a LoRa medium access mechanism and possible gains brought forth by implementing such a mechanism.

A Sigfox Energy Consumption Model.

Sigfox has become one of the main Low-Power Wide Area Network (LPWAN) technologies, as it has attracted the attention of the industry, academy and standards development organizations in recent years. Sigfox devices, such as sensors or actuators, are expected to run on limited energy sources; therefore, it is crucial to investigate the energy consumption of Sigfox. However, the literature has only focused on this topic to a very limited extent. This paper presents an analytical model that characterizes device current consumption, device lifetime and energy cost of data delivery with Sigfox. In order to capture a realistic behavior, the model has been derived from measurements carried out on a real Sigfox hardware module. The model allows quantifying the impact of relevant Sigfox parameters and mechanisms, as well as frame losses, on Sigfox device energy performance. Among others, evaluation results show that the considered Sigfox device, powered by a 2400 mAh battery, can achieve a theoretical lifetime of 1.5 or 2.5 years while sending one message every 10 min at 100 bit/s or 600 bit/s, respectively, and an asymptotic lifetime of 14.6 years as the message transmission rate decreases.

Extending SMS Service Coverage in Rural Areas by using LoRa Communication Technology

Mobile phone services are provided by operators in cities and along the roads in rural areas. In the last case, the coverage can reach a few kilometers far from the roads, depending on the available mobile technology. As a consequence, rural population have limited coverage or lack of message-based communication systems. In this work, we propose a solution based on low-power wide area network (LPWAN) technologies to extend the coverage of SMS service in rural areas in order to provide a message-based communication system for notification and telemetry. The proposal involves two devices called GSM node and remote node which form the complete system. The whole system uses three wireless communication technologies: GSM, LoRa and Bluetooth. To guarantee effective packet transmission, several computational strategies are implemented in each embedded communication hardware, such as algorithms that analyze the service availability before message transmission or guarantee delivery of messages. The proposed scheme takes advantage of both communication systems; those which operate on licensed bands in urban areas with good QoS and those which operate on non-licensed bands with high communication ranges. Several communication tests are implemented to evaluate the performance of the proposed solution. Results show the advantages of using low-consumption and long-range technologies to extend the SMS service coverage in rural areas. To the best of our knowledge, this is one of the first implementations and evaluations of a system that allows extending the SMS service coverage in rural areas based on LoRa technology.

A comparative Survey Study on LPWA IoT Technologies: Design, considerations, challenges and solutions

Based on the recent studies, by 2020 devices connected to internet are predicted to increase up to 22 billion. In compliance with the rapid growth of internet of things (IoT), Low power wide area Network (LPWA) technologies play a big role in connecting billions of devices. This paper aims to analyze the existing standard NB-IoT, LORA, Wi-Fi HaLow (802.11ah) used as low power wide area Network (LPWA) in wireless network, in term of their power efficiency, QoS, cost and coverage distance. The outcome of the research shows that each technology presents its advantages and disadvantages based on the type of the application considered. It is shown that despite the improvement of researches on existing LPWA technologies, there are still issues that need to be addressed. Thus, this paper gives some open issues for future research.

Security Risk Analysis of LoRaWAN and Future Directions

LoRa (along with its upper layers definition—LoRaWAN) is one of the most promising Low Power Wide Area Network (LPWAN) technologies for implementing Internet of Things (IoT)-based applications. Although being a popular technology, several works in the literature have revealed vulnerabilities and risks regarding the security of LoRaWAN v1.0 (the official 1st specification draft). The LoRa-Alliance has built upon these findings and introduced several improvements in the security and architecture of LoRa. The result of these efforts resulted in LoRaWAN v1.1, released on 11 October 2017. This work aims at reviewing and clarifying the security aspects of LoRaWAN v1.1. By following ETSI guidelines, we provide a comprehensive Security Risk Analysis of the protocol and discuss several remedies to the security risks described. A threat catalog is presented, along with discussions and analysis in view of the scale, impact, and likelihood of each threat. To the best of the authors’ knowledge, this work is one of the first of its kind, by providing a detailed security risk analysis related to the latest version of LoRaWAN. Our analysis highlights important practical threats, such as end-device physical capture, rogue gateway and self-replay, which require particular attention by developers and organizations implementing LoRa networks.

A Survey of LoRaWAN for IoT: From Technology to Application.

LoRaWAN is one of the low power wide area network (LPWAN) technologies that have received significant attention by the research community in the recent years. It offers low-power, low-data rate communication over a wide range of covered area. In the past years, the number of publications regarding LoRa and LoRaWAN has grown tremendously. This paper provides an overview of research work that has been published from 2015 to September 2018 and that is accessible via Google Scholar and IEEE Explore databases. First, a detailed description of the technology is given, including existing security and reliability mechanisms. This literature overview is structured by categorizing papers according to the following topics: (i) physical layer aspects; (ii) network layer aspects; (iii) possible improvements; and (iv) extensions to the standard. Finally, a strengths, weaknesses, opportunities and threats (SWOT) analysis is presented along with the challenges that LoRa and LoRaWAN still face.

Performance Analysis of LPWAN Using LoRa Technology for IoT Application

This paper was dedicated to study the performance of an Internet of Things (IoT) application using LoRa Wide Area Network (LoRaWAN). LoRa is a Low Power Wide Area Network (LPWAN) technology developed for IoT applications specifically. Due to the facts that LoRa is a new product, there are questions about its reliability. Hence, a conclusive experiment has been made. The experiment conducted to get an insight to LoRa received signal strength (RSSI) and packet loss. The analysis also includes a measurement of the application Signal to Noise Ratio (SNR) between the transmitter and receiver. The results of the experiment show that with a higher spreading factor, LoRa end device provides more immunity against multi-path and signal fading. The proposed IoT application based on this LoRa technology is for autonomous vehicle status information transmission and intervehicle communications, specifically deployed in UiTM Autonomous Vehicle 1 (UiTM AV1).

Performance Analysis of LPWAN Using LoRa Technology for IoT Application

This paper was dedicated to study the performance of an Internet of Things (IoT) application using LoRa Wide Area Network (LoRaWAN). LoRa is a Low Power Wide Area Network (LPWAN) technology developed for IoT applications specifically. Due to the facts that LoRa is a new product, there are questions about its reliability. Hence, a conclusive experiment has been made. The experiment conducted to get an insight to LoRa received signal strength (RSSI) and packet loss. The analysis also includes a measurement of the application Signal to Noise Ratio (SNR) between the transmitter and receiver. The results of the experiment show that with a higher spreading factor, LoRa end device provides more immunity against multi-path and signal fading. The proposed IoT application based on this LoRa technology is for autonomous vehicle status information transmission and intervehicle communications, specifically deployed in UiTM Autonomous Vehicle 1 (UiTM AV1).

Energy Efficient Policies for Data Transmission in Disruption Tolerant Heterogeneous IoT Networks.

The Internet-of-things facilitates the development of many groundbreaking applications. A large number of these applications involve mobile end nodes and a sparsely deployed network of base stations that operate as gateways to the Internet. Most of the mobile nodes, at least within city areas, are connected through low power wide area networking technologies (LPWAN) using public frequencies. Mobility and sparse network coverage result in long delays and intermittent connectivity for the end nodes. Disruption Tolerant Networks and utilization of heterogeneous wireless interfaces have emerged as key technologies to tackle the problem at hand. The first technology renders communication resilient to intermittent connectivity by storing and carrying data while the later increases the communication opportunities of the end nodes and at the same time reduces energy consumption whenever short-range communication is possible. However, one has to consider that end nodes are typically both memory and energy constrained devices which makes finding an energy efficient data transmission policy for heterogeneous disruption tolerant networks imperative. In this work we utilize information related to the spatial availability of network resources and localization information to formulate the problem at hand as a dynamic programming problem. Next, we utilize the framework of Markov Decision Processes to derive approximately optimal and suboptimal data transmission policies. We also prove that we can achieve improved packet transmission policies and reduce energy consumption, extending battery lifetime. This is achieved by knowing the spatial availability of heterogeneous network resources combined with the mobile node’s location information. Numerical resultsshow significant gains achieved by utilizing the derived approximately optimal and suboptimal policies.

Optimal Policy Derivation for Transmission Duty-Cycle Constrained LPWAN

Low-power wide-area network (LPWAN) technologies enable Internet of Things (IoT) devices to efficiently and robustly communicate over long distances, thus making them especially suited for industrial environments. However, the stringent regulations on the usage of certain industrial, scientific, and medical bands in many countries in which LPWAN operate limit the amount of time IoT motes can occupy the shared bands. This is particularly challenging in industrial scenarios, where not being able to report some detected events might result in the failure of critical assets. To alleviate this, and by mathematically modeling LPWAN-based IoT motes, we have derived optimal transmission policies that maximize the number of reported events (prioritized by their importance) while still complying with current regulations. The proposed solution has been customized for two widely known LPWAN technologies: 1) LoRa and 2) Sigfox. Analytical results reveal that our solution is feasible and performs remarkably close to the theoretical limit for a wide range of network activity patterns.

Energy Consumption Model for Sensor Nodes Based on LoRa and LoRaWAN.

Energy efficiency is the key requirement to maximize sensor node lifetime. Sensor nodes are typically powered by a battery source that has finite lifetime. Most Internet of Thing (IoT) applications require sensor nodes to operate reliably for an extended period of time. To design an autonomous sensor node, it is important to model its energy consumption for different tasks. Each task consumes a power consumption amount for a period of time. To optimize the consumed energy of the sensor node and have long communication range, Low Power Wide Area Network technology is considered. This paper describes an energy consumption model based on LoRa and LoRaWAN, which allows estimating the consumed power of each sensor node element. The definition of the different node units is first introduced. Then, a full energy model for communicating sensors is proposed. This model can be used to compare different LoRaWAN modes to find the best sensor node design to achieve its energy autonomy.

Smart Choice for the Smart Grid: Narrowband Internet of Things (NB-IoT)

The low power wide area network (LPWAN) technologies, which is now embracing a booming era with the development in the Internet of Things (IoT), may offer a brand new solution for current smart grid communications due to their excellent features of low power, long range, and high capacity. The mission-critical smart grid communications require secure and reliable connections between the utilities and the devices with high quality of service (QoS). This is difficult to achieve for unlicensed LPWAN technologies due to the crowded license free band. Narrowband IoT (NB-IoT), as a licensed LPWAN technology, is developed based on the existing long-term evolution specifications and facilities. Thus, it is able to provide cellular-level QoS, and henceforth can be viewed as a promising candidate for smart grid communications. In this paper, we introduce NB-IoT to the smart grid and compare it with the existing representative communication technologies in the context of smart grid communications in terms of data rate, latency, range, etc. The overall requirements of communications in the smart grid from both quantitative and qualitative perspectives are comprehensively investigated and each of them is carefully examined for NB-IoT. We further explore the representative applications in the smart grid and analyze the corresponding feasibility of NB-IoT. Moreover, the performance of NB-IoT in typical scenarios of the smart grid communication environments, such as urban and rural areas, is carefully evaluated via Monte Carlo simulations.

On the Mobile Communication Requirements for the Demand-Side Management of Electric Vehicles

The rising concerns about global warming and environmental pollution are increasingly pushing towards the replacement of road vehicles powered by Internal Combustion Engines (ICEs). Electric Vehicles (EVs) are generally considered the best candidates for this transition, however, existing power grids and EV management systems are not yet ready for a large penetration of EVs, and the current opinion of the scientific community is that further research must be done in this field. The so-called Vehicle-to-Grid (V2G) concept plays a relevant role in this scenario by providing the communication capabilities required by advanced control and Demand-Side Management (DSM) strategies. Following this research trend, in this paper the communication requirements for the DSM of EVs in urban environments are discussed, by focusing on the mobile communication among EVs and smart grids. A specific system architecture for the DSM of EVs moving inside urban areas is proposed and discussed in terms of the required data throughput. In addition, the use of a Low-Power Wide-Area Network (LPWAN) solution—the Long-Range Wide Area Network (LoRaWAN) technology—is proposed as a possible alternative to cellular-like solutions, by testing an experimental communication infrastructure in a real environment. The results show that the proposed LPWAN technology is capable to handle an adequate amount of information for the considered application, and that one LoRa base station is able to serve up to 438 EVs per cell, and 1408 EV charging points.

Performance Evaluation of LoRa Considering Scenario Conditions

New verticals within the Internet of Things (IoT) paradigm such as smart cities, smart farming, or goods monitoring, among many others, are demanding strong requirements to the Radio Access Network (RAN) in terms of coverage, end-node’s power consumption, and scalability. The technologies employed so far to provide IoT scenarios with connectivity, e.g., wireless sensor network and cellular technologies, are not able to simultaneously cope with these three requirements. Thus, a novel solution known as Low Power - Wide Area Network (LP-WAN) has emerged as a promising alternative to provide with low-cost and low-power-consumption connectivity to end-nodes spread in a wide area. Concretely, the Long-Range Wide Area Network (LoRaWAN) technology is one of the LP-WAN platforms that is receiving greater attention from both the industry and the academia. For that reason, in this work, a comprehensive performance evaluation of LoRaWAN under different environmental conditions is presented. The results are obtained from three real scenarios, namely, urban, suburban, and rural, considering both dynamic and static conditions, hence a discussion about the most proper LoRaWAN physical-layer configuration for each scenario is provided. Besides, a theoretical coverage study is also conducted by the use of a radio planning tool considering topographic maps and a precise propagation model. From the attained results, it can be concluded that it is necessary to evaluate the propagation conditions of the deployment scenario prior to the system implantation in order to reach a compromise between the robustness of the network and the transmission data-rate.

Comparative analysis of the application of different Low Power Wide Area Network technologies in power grid

Low Power Wide Area Network (LPWAN) technologies developed rapidly in recent years, but the application principle of different LPWAN technologies in power grid is still not clear. This paper gives a comparative analysis of two mainstream LPWAN technologies including NB-IoT and LoRa, and gives an application suggestion of these two LPWAN technologies, which can guide the planning and construction of LPWAN in power grid.

Research of the application of the Low Power Wide Area Network in power grid

Low Power Wide Area Network (LPWAN) technologies developed rapidly in recent years, but these technologies have not make large-scale applications in different application scenarios of power grid. LoRa is a mainstream LPWAN technology. This paper makes a comparison test of the signal coverage of LoRa and other traditional wireless communication technologies in typical signal environment of power grid. Based on the test results, this paper gives an application suggestion of LoRa in power grid services, which can guide the planning and construction of the LPWAN in power grid.