Low Power Wide Area Technologies Research Articles

Adaptive Mobility-Based IoT LoRa Clustering Communication Scheme

Long Range (LoRa) as a low-power wide-area technology is distinguished by its robust long-distance communications tailored for Internet of Things (IoT) networks. Because LoRa was primarily designed for stationary devices, when applied to mobile devices, they become susceptible to frequent channel attenuation. Such a condition can result in packet loss, higher energy consumption, and extended transmission times. To address these inherent challenges posed by mobility, we propose an adaptive mobility-based IoT LoRa clustering communication (AMILCC) scheme, which employs the 2D random waypoint mobility model, strategically partitions the network into optimal spreading factor (SF) regions, and incorporates an adaptive clustering approach. The AMILCC scheme is bolstered by a hybrid adaptive data rate (HADR) mechanism categorized into two approaches, namely intra-SF and inter-SF region HADRs, derived from the standard network-based ADR mechanism for stationary devices, to ensure efficient resource allocation for mobile IoT LoRa devices. Evaluation results show that, based on simulations at low mobility speeds of up to 5 m/s, AMILCC successfully maximizes the packet success ratio to the gateway (GW) by over 70%, reduces energy consumption by an average of 55.5%, and minimizes the end-to-end delay by 47.62%, outperforming stationary schemes. Consequently, AMILCC stands as a prime solution for mobile IoT LoRa networks by balancing the high packet success ratio (PSR) with reliability with energy efficiency.

Saffron corm sorting and rot treatment strategy for productivity enhancement for precision agriculture

One of the most economical and precious spices ever known is saffron. It has innumerable pharmaceutical applications, and its cultivation is limited to certain topographic regions throughout the world. Although efforts are continuously being made to increase productivity and increase the area under cultivation, there are multiple factors leading to its low production. Corm size is one of the major factors affecting the quality and production of saffron. The more the corm size for a plantation, the better the yield of the crop. This can pose a serious threat to saffron cultivators who are not able to get good quality corms and sort quality corms from infected ones. Additional factors affecting saffron cultivation include attack by fungus leading to corm rots and sclerotineal disease. In this paper, IoT (Internet of Things) has been used to provide an energy-efficient, ready-to-use, reliable, and user-friendly solution for corm sorting and treatment before sowing to promote quality, better yield and minimized wastage due to corm rots. After sorting the corms, they are treated with 0.2% of tiabendazole fungicide solution and dried, before sowing and for long-term storage. Firstly, sorting and treatment system for the saffron corms processing as per weight is proposed. First two-layer cleaning mechanism to remove foreign substances, then three-step treatment has been applied to remove microorganisms. An automated conveyor system equipped with IoT devices was used for sorting and treating saffron corms. Different energy efficient LPWA (Low Power Wide Area) and LTE (Long Term Evolution) technologies used in the framework, for communication are NB-IoT (Narrow Band IoT) and LoRa (Long Range Radio).

A Design for a Lithium-Ion Battery Pack Monitoring System Based on NB-IoT-ZigBee

With environmental issues arising from the excessive use of fossil fuels, clean energy has gained widespread attention, particularly the application of lithium-ion batteries. Lithium-ion batteries are integrated into various industrial products, which necessitates higher safety requirements. Narrowband Internet of Things (NB-IoT) is an LPWA (Low Power Wide Area Network) technology that provides IoT devices with low-power, low-cost, long-endurance, and wide-coverage wireless connectivity. This study addresses the shortcomings of existing lithium-ion battery pack detection systems and proposes a lithium-ion battery monitoring system based on NB-IoT-ZigBee technology. The system operates in a master-slave mode, with the subordinate module collecting and fusing multi-source sensor data, while the master control module uploads the data to local monitoring centers and cloud platforms via TCP and NB-IoT. Experimental validation demonstrates that the design functions effectively, accomplishing the monitoring and protection of lithium-ion battery packs in energy storage power stations.

Design and FPGA-Based Hardware Implementation of NB-IoT Physical Uplink Shared Channel Transmitter and Physical Downlink Shared Channel Receiver

With the anticipated growth of the internet of things (IoT) market, many low-power wide-area (LPWA) technologies have been introduced to connect a wide range of IoT devices with varying performance requirements. The narrowband internet of things (NB-IoT) is a 3rd generation partnership project (3GPP) standardized LPWA technology that meets most IoT service requirements. In this paper, the design and implementation of the physical uplink transmitting chain as well as the physical downlink receiving chain of the NB-IoT user equipment (UE) are presented. Both chains’ main blocks are designed to follow the 3GPP NB-IoT LTE standard Release 14 (Rel-14). The whole design is experimentally implemented on the Virtex 7 (VC 709) Connectivity kit, and all performance metrics are reported. Moreover, an NB-IoT base station is implemented and integrated with the two prototyped UEs to set-up an NB-IoT system, which is employed to send data from one UE to another UE through the NB-IoT base station using two FPGAs (one to implement the sending UE and the other one to implement the receiving UE) and three universal software radio peripherals (USRPs) B200 (one to implement the RF front-end of the transmitting UE FPGA, one to implement the base station RF front-end, and one to implement the RF front-end of the receiving UE FPGA). Experimental results show that the implemented NB-IoT system is working successfully, as the two NB-IoT UEs communicate together successfully through the NB-IoT base station and exchange the data properly.

Implicit Overhearing Node-Based Multi-Hop Communication Scheme in IoT LoRa Networks.

Long range (LoRa) is a low-power wide-area technology because it is eminent for robust long-distance, low-bitrate, and low-power communications in the unlicensed sub-GHz spectrum used for the Internet of things (IoT) networks. Recently, several multi-hop LoRa networks have proposed schemes with explicit relay nodes to partially mitigate the path loss and longer transmission time bottlenecks of the conventional single-hop LoRa by focusing more on coverage expansion. However, they do not consider improving the packet delivery success ratio (PDSR) and the packet reduction ratio (PRR) by using the overhearing technique. Thus, this paper proposes an implicit overhearing node-based multi-hop communication (IOMC) scheme in IoT LoRa networks, which exploits implicit relay nodes for performing the overhearing to promote relay operation while satisfying the duty cycle regulation. In IOMC, implicit relay nodes are selected as overhearing nodes (OHs) among end devices with a low spreading factor (SF) in order to improve PDSR and PRR for distant end devices (EDs). A theoretical framework for designing and determining the OH nodes to execute the relay operations was developed with consideration of the LoRaWAN MAC protocol. Simulation results verify that IOMC significantly increases the probability of successful transmission, performs best in high node density, and is more resilient to poor RSSI than the existing schemes.

Research on WLAN scenario optimisation policy based on IoT smart campus

In this paper, we analysed the development history of IoT wireless technology, and further analysed the need for dedicated low power wide area technology in IoT systems. Because of the internet of things (IoT), which connects various network-embedded devices to the internet, this paper studies the problems in WLAN of college students' dormitory, as well as introducing and analysing the optimal way of the short-distance WLAN technology in IoT. After reviewing the methods to optimise WLAN optimisation, WLAN scenarios for the student dormitory are studied in depth and the optimisation scheme of wireless local area networks based on IoT short-range technology is proposed. Targeted network optimisation strategies are elaborated. Comparisons revealed that the optimisation resulted in significant improvement in terms of signal strength, latency, packet loss, throughput, propagation speed, and roaming success rate. The network became more stable, with better performance and user experience. In addition, the new network solved many previous issues and achieved the desired results.

Survey of Collision Avoidance Systems for Underground Mines: Sensing Protocols.

With the growing number of unintentional interactions occurring in underground mines, Collision Avoidance System (CAS) establishment and maintenance has become an urgent need for mining industries to enhance their risk profile and improve construction safety. Usually, most collision accidents can be divided into three different categories in line with the involved participants and infrastructure condition. The accidents pose a great risk of financial cost to mining companies and even cause casualties. In detail, this paper presents an intensive study survey of positioning techniques, including ranging algorithms, to accommodate the demands of various proximity sensors and improve the capability of situational awareness. Then, we exploit the importance of the communication system, prevalent low-power wide-area technologies and related communication protocols. The effectiveness of communication systems decides and facilitates the success of the final integrated system that can be used to fundamentally address the problem of collision avoidance. For the purpose of collaboration between communication systems and other executive departments, a series of systematic comparisons of pertinent technologies and algorithms is given near the end, followed by a brief discussion on the best choice among these options. In the proposed solution, the overall end-to-end delay can be minimised to a few nanoseconds and the localisation accuracy can achieve centimetre level when operating in the range of 100 m.

Localization of transport and logistics units through IoT Technologies

The paper deals with the application of IoT (Internet of Things) technologies for localization or other monitoring functions for logistic units using the IoT element. At the beginning of the paper, we analysed currently the most used technologies for localization and monitoring of logistic units. Then, we described the basic requirements for LPWA (Low-Power Wide-Area) technologies, including the information they can collect and provide. The main part of the paper is devoted to the design and testing of IoT solutions based on one of the LPWAN (Low-Power Wide-Area Network) technologies for a real logistics company. The conclusion of the paper is dedicated to testing the evaluation and prognosis of further use of LPWAN technologies.

A Survey on LPWAN-5G Integration: Main Challenges and Potential Solutions

The popularity of Internet of Things (IoT) has resulted in increased deployments of Low Power Wide Area (LPWA) technologies for both commercial and private services due to their performance and cost advantages. Although Low Power Wide Area Networks (LPWANs) have the advantages of low power consumption, wide coverage, low-cost and scalability, they generally have lower data rates and lower reliability, thus limiting their suitability for a wider range of industrial use cases such as process control and high data rate multimedia applications. To overcome this, LPWA technologies can be integrated into 5G, a flexible, scalable, agile and programmable mobile communication system. In this paper, we provide a survey on LPWAN-5G integration focusing on the main integration challenges and potential solutions. We firstly compare popular licensed and unlicensed LPWA technologies, and then introduce the 5G architecture and enabling technologies for LPWAN-5G integration. Finally, we discuss in detail the challenges and potential solutions of LPWAN-5G integration, covering all the important aspects including hybrid architecture, security, mobility, interoperability between LPWANs, and coexistence with other wireless technologies. From our analysis, it can be seen that LPWAN-5G integration tends to evolve from access network to core network.

LoRa‐aided outdoor localization system: RSSI or TDoA?

Internet of Things (IoT) is a hot research topic, and typically involves communication between small devices in order to sense, react, and reinvent our way of living. To this end, the localization of such small devices is of great importance for most applications. Between the many applications of IoT, there are those which require low power communication between long ranges, which are entitled Low Power Wide Area (LPWA) communications. One of the main LPWA technologies is the Long Range (LoRa), which does not support native localization. In order to overcome such a problem, a possible approach is to use the Global Positioning Systems (GPS), but it can be costly when aiming for cheaper and simpler devices. This paper evaluates the accuracy of a LoRa‐aided outdoor localization system when locating GPS‐free Target Nodes (TN) through the use of Anchor Nodes (AN) with known positions. Two different indicators are used, namely the Received Signal Strength Indicator (RSSI) and the Time Difference of Arrival (TDoA). Our results indicate that, in general, TDoA presents an improved accuracy over RSSI, with errors ranging from 66 to 253 m in the considered scenario.

Testbed for LoRaWAN Security: Design and Validation through Man-in-the-Middle Attacks Study

The low-power wide-area (LPWA) technologies, which enable cost and energy-efficient wireless connectivity for massive deployments of autonomous machines, have enabled and boosted the development of many new Internet of things (IoT) applications; however, the security of LPWA technologies in general, and specifically those operating in the license-free frequency bands, have received somewhat limited attention so far. This paper focuses specifically on the security and privacy aspects of one of the most popular license-free-band LPWA technologies, which is named LoRaWAN. The paper’s key contributions are the details of the design and experimental validation of a security-focused testbed, based on the combination of software-defined radio (SDR) and GNU Radio software with a standalone LoRaWAN transceiver. By implementing the two practical man-in-the-middle attacks (i.e., the replay and bit-flipping attacks through intercepting the over-the-air activation procedure by an external to the network attacker device), we demonstrate that the developed testbed enables practical experiments for on-air security in real-life conditions. This makes the designed testbed perspective for validating the novel security solutions and approaches and draws attention to some of the relevant security challenges extant in LoRaWAN.

Performance of distributed coordination function for serving IoT applications

The Internet of Things (IoT) interconnects “things” and autonomously exchanges data between them. It is expected that there are more than seven billion of connections interconnected by low-power wide-area (LPWA) networks to support IoT services before 2025. Several LPWA technologies are gaining popularity recently, such as LoRa and NB-IoT. Despite of their advertised advantages over conventional technologies such as low power, long range, and cheap module, several studies and field tests shows that they cannot communicate in long-range, the DIY supporting modules are not really power efficient, and the development are rather expensive. While commercial IoT networks have yet to be widely deployed, many smart connected devices use WiFi-based connectivity. This motivates us to study and evaluate the performance of WiFi’s medium access protocol for this new use case of IoT. In the experiment, our proposed analytical model is evaluated against a custom-made Monte Carlo simulation. The result shows that our model is accurate in estimating the system performance in term of normalized throughput.

Control Communication Co-Design for Wide Area Cyber-Physical Systems

Wide Area Cyber-Physical Systems (WA-CPSs) are a class of control systems that integrate low-powered sensors, heterogeneous actuators, and computer controllers into large infrastructure that span multi-kilometre distances. Current wireless communication technologies are incapable of meeting the communication requirements of range and bounded delays needed for the control of WA-CPSs. To solve this problem, we use a Control Communication Co-design approach for WA-CPSs, that we refer to as the C 3 approach, to design a novel Low-Power Wide Area (LPWA) MAC protocol called Ctrl-MAC and its associated event-triggered controller that can guarantee the closed-loop stability of a WA-CPS. This is the first article to show that LPWA wireless communication technologies can support the control of WA-CPSs. LPWA technologies are designed to support one-way communication for monitoring and are not appropriate for control. We present this work using an example of a water distribution network application, which we evaluate both through a co-simulator (modeling both physical and cyber subsystems) and testbed deployments. Our evaluation demonstrates full control stability, with up to 50% better packet delivery ratios and 80% less average end-to-end delays when compared to a state-of-the-art LPWA technology. We also evaluate our scheme against an idealised, wired, centralised, control architecture, and show that the controller maintains stability and the overshoots remain within bounds.

RETRACTED: Optimization of Communication Network Fault Identification Based on NB-IoT

The Internet of Things (IoT) has developed an industrial and medical application in dramatic growth in recent years. Narrow Band-Internet of Things (NB-IoT) is a wireless communication and low power wide area technology based on new IoT devices and enables various services to grow. NB-IoT communication significantly increases the power consumption of user equipment, computer capacity, and spectrum performance. Network communication is complex, and the amount of information these networks have made it extremely difficult to manage the transmissions. Since the communication network failure is inevitable, rapid detection, identification, and recovery are the most reliable; it is essential to the high-speed operation. Narrow Band-IoT (NB-IoT) networking technology has proposed the idea of detecting network communication fault. The NB-IoT technique can help save a lot of energy by significantly reducing the number of retransmission required. The proposed technology proves that this research is a powerful proposition for achieving the ideal energy potential. Performance analysis and simulation results show that the detection mechanism can improve transmission efficiency and effectively reduce network communication failures power consumption.

Complexity-Effective Sequential Detection of Synchronization Signal for Cellular Narrowband IoT Communication Systems

Narrowband Internet of Things (NB-IoT) is one of the most promising low-power wide-area technologies to support low cost, massive connection, deep coverage, and low-power consumption. This article proposes a complexity-effective narrowband secondary synchronization signal (NSSS) detection scheme for the cellular NB-IoT communication system. By taking advantage of the NSSS sequence, the search space of NSSS hypotheses is reduced by decoupling the detection of complementary Walsh sequence and Zadoff-Chu sequence in a sequential manner. Such a detection strategy allows reduced-complexity NSSS detection in the NB-IoT system. Both numerical and simulation results are presented to verify the effectiveness of the proposed NSSS detection scheme. The simulation results show that the proposed NSSS detector achieves a considerable complexity reduction at the cost of some performance degradation, compared to the conventional NSSS detector.

CELLULAR NETWORK RESOURCE DISTRIBUTION METHODS FOR THE JOINT SERVICING OF REAL-TIME MULTISERVICE TRAFFIC AND GROUPED IOT TRAFFIC

Immense growth in the volumes and multiplicity of data to be collected in future Internet of Things (IoT) applications is one of the crucial challenges for the networking organizations as they develop from 4G+ to true 5G systems. Particularly bulk of this traffic includes complex, unstructured and varied data (Big Data) evolve from smart networking ecosystems (LTE-devices, NB-IoT devices). Although 5G offers many low power wide area technologies (Lora WAN, GSM and NB-IoT etc.), principally NB-IoT seems very promising addressing the problem because of its certain characteristics like high fault tolerance, delay tolerance, higher coverage area etc. However, due to the limited bandwidth (180 kHz) availability one of the challenges is how to efficiently use these resources to support and handle massive number of growing IoT devices, also resource management and allocation methodology between LTE and NB-IoT traffic flows. In this context, several key issues for IoT communications in 5G networks should be addressed to satisfy quality of service (QoS) provisioning. In this paper, we proposed a mathematical model for Operator Surveillance systems for sharing radio resources between LTE and NB-IoT. The model utilizes the technique of network slicing for resource management. The proposed techniques provide scenarios that aims to offer a trade-off between the two types of traffics by guaranteeing the network performance and avoiding unproductive utilization of available resources.

A Tutorial on NB-IoT Physical Layer Design

The Internet of Things (IoT) is transforming the whole of society. It represents the next evolution of the Internet and will significantly improve the ability to gather and analyze data, as well as the ability to control devices remotely. In this respect, the usage of connected devices is continuously growing with the expansion of the applications being offered to individuals and industries. To address IoT market needs, many low-power wide-area (LPWA) technologies have been developed, some operating on licensed frequencies (e.g., narrowband-IoT [NB-IoT] and Long-Term Evolution-M [LTE-M]), and others on unlicensed frequencies (e.g., LoRa, Sigfox, etc.). In this article, we address the Release 13 of the NB-IoT 3rd generation partnership project (3GPP) standardized LPWA technology and provide a tutorial on its physical layer (PHY) design. Specifically, we focus on the characteristics and the scheduling of downlink and uplink physical channels at the NB-IoT base station side and the user equipment (UE) side. The goal is to help readers easily understand the NB-IoT system without having to read all the 3GPP specifications or the state-of-the-art papers that generally describe the system. To this end, each presented concept is followed by examples and concrete use-cases to further aid in the reader’s comprehension. Finally, we briefly describe and highlight the new features added to the NB-IoT system in Releases 14 and 15.

On the Real Capacity of LoRa Networks: The Impact of Non-Destructive Communications

LoRa technology has recently gained popularity, becoming one of the most promising low power wide area technologies for the Internet of Things due to its proprietary modulation scheme, the use of unlicensed sub-GHz frequency bands, and a non-destructive communication property, enabling that the reception of a packet is not interfered by the transmission of one with weaker signal. Based on an exhaustive evaluation setup, this work characterizes the capture effect in the event of two or more LoRa concurrent transmissions. These results are afterwards used to evaluate the real performance of large scale Low Power Wide Area Networks (LPWANs) based on the LoRaWAN protocol, showing that the real network capacity of LoRaWAN does not follow the traditional pure Aloha performance, widely used in the literature.

Characterization of LoRa Point-to-Point Path Loss: Measurement Campaigns and Modeling Considering Censored Data

Low-power wide-area technologies have demonstrated their usefulness in a wide variety of Internet of Things applications. New applications are emerging, requiring a mesh or point-to-point (P2P) topology, in contrast to the conventional star-of-stars topology. In this article, we evaluate the coverage and model the path loss (PL) of these links, based on experimental campaigns in three environments: 1) urban; 2) forest; and 3) coastal. More obstructions, scattering, and diffraction are encountered because the terminals are typically at a low height. This results in a higher PL compared to the star-of-stars topology. Consequently, more packets drop below the receiver sensitivity. Realistic PL parameters are estimated by also taking the censored data into account. The packet error ratio is determined based on the estimated PL parameters to evaluate the performance of P2P links. Even in these adverse environments, 80% of the transmitted packets are successfully received at a distance of approximately 200 m. Moreover, a range of over 4 km is observed in the line-of-sight scenario. Despite the unfavorable radio propagation in the urban scenario and the densely forested terrain, a maximum range of 1 km is achieved.

Radio resource management framework for energy‐efficient communications in the Internet of Things

AbstractThe Internet of Things (IoT) is the vision of a global network that connects various physical world objects to the IT infrastructure through a wireless medium. Despite the availability of a number of mature radio access technologies such as GSM, Long‐Term Evolution, Wi‐Fi, and due to the current progress made in developing 5G technology, more and more IoT operators are opting to use low‐power wide‐area (LPWA) technologies due to their low cost and easy deployment. However, recent studies show that the radio resource allocation used in these technologies is not scalable. This limitation often results in packet collisions, retransmission and unnecessary waste of scarce energy resources. In this paper, we propose a radio resource management framework, based on software‐defined network (SDN), to overcome the inefficient radio resource allocation of LPWA technologies. This is possible through the centralized nature of SDN, which allows collecting network monitoring information to analyze and calculate the optimal channel assignment configuration across the IoT network. We perform software‐defined radio‐based spectrum monitoring within the real IoT network platform in 868 MHz bands in which the latest IoT technologies, ie, LoRa and SigFox, operate. We demonstrate, through extensive simulations, that the proposed approach provides a better radio resource allocation for LPWA, reduces the number of packet collisions, and significantly improves the energy efficiency of the IoT communications.