Low-power Wireless Technologies Research Articles

The Downside of Software-Defined Networking in Wireless Network

Mobile traffic volumes have grown exponentially because of the increase in services and applications. Traditional networks are complex to manage because the forwarding, control, and management planes are all bundled together and, thus, administrators are supposed to deploy high-level policies, as each vendor has its own configuration methods. Software-Defined Networking (SDN) is considered the future paradigm of communication networks. It decouples control logic from its underlying hardware, thereby promoting logically centralized network control and making the network more programmable and easy to configure. Low-power wireless technologies are moving toward a multitenant and multiapplication Internet of Things (IoT), which requires an architecture with scalable, reliable, and configured solutions. However, employing an SDN-based centralized architecture in the environment of a low-power wireless IoT network introduces significant challenges, such as difficult-to-control traffic, unreliable links, network contention, and high associated overheads that can significantly affect the performance of the network. This paper is a contribution toward a performance evaluation for the use of SDN in wireless networking by evaluating the latency, packet drop ratio (PDR), data extraction rate (DER), and overheads. The results show that SDN adds a high percentage of overheads to the network, which is about 43% of the 57% user packets, and the DER drops when the number of mesh nodes are increased, in addition to the high loss that was observed for packets that traveled over more hops.

Low Power Communication Technologies in Water Quality Monitoring System: A Review

The core part of the internet of things (IoT) is the wireless sensor network (WSN). WSN makes sensor-based devices communicate without any human action. In recent years, WSN and IoT technologies have transformed the environmental monitoring field. Water quality monitoring is one of the main environmental monitoring application. The communication unit is the main energy-consuming part of WSN. Since most of the WSN is powered by a battery, low power communication is very essential. So the main challenges in water quality monitoring applications are low power and wide communication coverage. This paper provides a critical review of various communication technologies used in water quality monitoring system. The communication technologies are ZigBee, Wi-Fi and newly emerging low power wireless technologies like LoRa, Sigfox and NB-IoT. The comparison of these technologies by considering different factors is also provided.

Smart Parking System with Dynamic Pricing, Edge-Cloud Computing and LoRa.

A rapidly growing number of vehicles in recent years cause long traffic jams and difficulty in the management of traffic in cities. One of the most significant reasons for increased traffic jams on the road is random parking in unauthorized and non-permitted places. In addition, managing of available parking places cannot achieve the expected reduction in traffic congestion related problems due to mismanagement, lack of real-time parking guidance to the drivers, and general ignorance. As the number of roads, highways and related resources has not increased significantly, a rising need for a smart, dynamic and effective parking solution is observed. Accordingly, with the use of multiple sensors, appropriate communication network and advanced processing capabilities of edge and cloud computing, a smart parking system can help manage parking effectively and make it easier for the vehicle owners. In this paper, we propose a multi-layer architecture for smart parking system consisting of multi-parametric parking slot sensor nodes, latest long-range low-power wireless communication technology and Edge-Cloud computation. The proposed system enables dynamic management of parking for large areas while providing useful information to the drivers about available parking locations and related services through near real-time monitoring of vehicles. Furthermore, we propose a dynamic pricing algorithm to yield maximum possible revenue for the parking authority and optimum parking slot availability for the drivers.

Error probability performance of chirp modulation in uncoded and coded LoRa systems

This paper focuses on the error probability performance of LoRa, a long-range low-power wireless communication technology suited for the Internet of Things (IoT). We propose accurate approximations for the bit error probability of the uncoded LoRa chirp modulation in additive white Gaussian noise (AWGN) channel. Our approach, which is based on a smart modification of a union bound on the error probability, is applied to both coherent and noncoherent detection. Simulation results show that the proposed theoretical bit error rate (BER) expressions are more accurate than the existing BER approximations that use similar complexity. We show that the proposed BER expressions are valid for both orthogonal and quasi-orthogonal LoRa, and are easier to compute than the exact BER for orthogonal signaling. Moreover, we extend the theoretical performance analysis to coded LoRa systems and we propose analytical BER expressions for Hamming-coded LoRa signals with hard-decision decoding. In addition, we analyze by simulation the error probability of coded LoRa systems with soft-decision decoding in multipath channels. The obtained results (both theoretical and simulated) quantify the performance gains of channel coding with respect to uncoded transmissions, in both AWGN and multipath channels, for coded LoRa systems that use the same bandwidth (with lower bit rate) of the uncoded LoRa system.

Drone-Enabled Internet-of-Things Relay for Environmental Monitoring in Remote Areas Without Public Networks

Advancements in the Internet of Things (IoT) have led to the revolutionary potential to achieve intelligent environmental monitoring. However, extreme conditions across hard-to-reach areas, where public ground networks do not provide sufficient coverage, have resulted in the difficult backhaul of monitoring data from remote areas of interest. Because of the urgent demand for low-cost data collection in such areas, this article proposes a novel drone-enabled IoT relay system to provide high-speed data collection to support remote environmental monitoring. The high-speed ability of 5-GHz communication technology was exploited to reduce the time required for data transmission between ground monitoring devices and drone. Meanwhile, the long-range (LoRa) technology, as a low-power and long-distance wireless communication technology, is adopted as a wake-up strategy for waking up the high-power 5-GHz module. Based on 5 GHz and LoRa technology, a drone-based onboard relay and ground intelligent terminal are designed. An application is used to demonstrate the feasibility of the designed system. Numerous real-world experiments validate the effectiveness of the designed drone-enabled IoT relay system and show its capability for high-speed data collection. The field experiments demonstrate that the system collects cached data with a stable 3.5-MB/s throughput at an altitude of 140 m. The breakthroughs in the drone-enabled IoT relay facilitate intelligent environmental monitoring in remote areas without public networks and provide a new perspective on data backhaul over areas of interest.

Emerging Wireless Sensor Networks and Internet of Things Technologies-Foundations of Smart Healthcare.

Future smart healthcare systems—often referred to as Internet of Medical Things (IoMT) – will combine a plethora of wireless devices and applications that use wireless communication technologies to enable the exchange of healthcare data. Smart healthcare requires sufficient bandwidth, reliable and secure communication links, energy-efficient operations, and Quality of Service (QoS) support. The integration of Internet of Things (IoT) solutions into healthcare systems can significantly increase intelligence, flexibility, and interoperability. This work provides an extensive survey on emerging IoT communication standards and technologies suitable for smart healthcare applications. A particular emphasis has been given to low-power wireless technologies as a key enabler for energy-efficient IoT-based healthcare systems. Major challenges in privacy and security are also discussed. A particular attention is devoted to crowdsourcing/crowdsensing, envisaged as tools for the rapid collection of massive quantities of medical data. Finally, open research challenges and future perspectives of IoMT are presented.

WIRELESS SENSOR NETWORK FOR ENVIRONMENTAL MONITORING IN HILL AREAS AS A PREVENTIVE MEASURE OF GLOBAL WARMING

Wireless Sensor Network (WSN) is used in various applications such as area monitoring, healthcare monitoring, industrial and environmental monitoring and so on. Spatially dispersing various sensors and creating a network for knowing the physical conditions of the environment is known as WSN. In this paper, WSN is created for monitoring the environment in hill areas for detecting the various abnormalities such as forest fire, deforestation and landslides. Long Range (LoRa) low power wireless technology and sensors for monitoring forest fire, deforestation and landslides are used in WSN. The data collected in the central point is processed for further evaluation and alerts the authorities through SMS and internet. Global System for Mobile (GSM) Communication modem with Global Packet Radio System (GPRS) enabled SIM card is used for enabling internet service for the central data collecting unit. The system is powered from battery which is recharged by electrical energy converted from solar energy using solar panel.

A Realistic Deployment of Named Data Networking in the Internet of Things

IP has been designed for Internet decades ago to connect computers and share expensive resources such as tape drives and printers. Nowadays, Internet of Things and other emerging applications use Internet to fetch and exchange content such as monitoring data and movies. This content-centric use of Internet highlights the limitations of the IP architecture. IETF Working Groups spend significant efforts to adapt the traditional IP stack to IoT systems, but the shortcomings of IP remain difficult to hide. In this context, the recently emerged Named Data Networking (NDN) architecture promises a better support of IoT systems and future Internet applications. This paper describes a realistic IoT architecture based on NDN. In practice, an integration of NDN in IoT devices over low-power wireless technologies is designed, deployed and evaluated considering a Smart Farming application scenario. This work aims to show that NDN is more suitable than IP for IoT systems, by giving another look at IP-based solutions for the IoT such as 6LoWPAN. For that, we design a simple packet compression scheme and a lightweight forwarding strategy that is compliant with the NDN vision while managing constrained devices. Evaluation result demonstrate the flexibility of NDN to support IoT environments.

Fast Feedback Control over Multi-hop Wireless Networks with Mode Changes and Stability Guarantees

Closing feedback loops fast and over long distances is key to emerging cyber-physical applications; for example, robot motion control and swarm coordination require update intervals of tens of milliseconds. Low-power wireless communication technology is preferred for its low cost, small form factor, and flexibility, especially if the devices support multi-hop communication. Thus far, however, feedback control over multi-hop low-power wireless networks has only been demonstrated for update intervals on the order of seconds. To fill this gap, this article presents a wireless embedded system that supports dynamic mode changes and tames imperfections impairing control performance (e.g., jitter and message loss), and a control design that exploits the essential properties of this system to provably guarantee closed-loop stability for physical processes with linear time-invariant dynamics in the presence of mode changes. Using experiments on a cyber-physical testbed with 20 wireless devices and multiple cart-pole systems, we are the first to demonstrate and evaluate feedback control and coordination with mode changes over multi-hop networks for update intervals of 20 to 50 milliseconds.

PPM: Preamble and Postamble-Based Multi-Packet Reception for Green ZigBee Communication

ZigBee, a low-power wireless communication technology, has been used in various applications, such as smart health/home/buildings. The proliferation of ZigBee-based applications (and thus devices), however, makes the concurrent transmissions—i.e., multiple transmitters send packets to the same receiver at the same time—common in practice, leading to inevitable collisions. Either retransmissions caused by collisions or the collision avoidance mechanism, e.g., CSMA/CA, introduces plenty of energy consumption. To facilitate the green and concurrent transmissions of ZigBee, we design pre/post-amble-based multi-packet reception (PPM), a method that recovers the collided ZigBee messages by exploiting their collision-free chips and the overlapped chips in their pre/post-ambles. We elaborately attach short postamble to standard ZigBee packet by manipulating the ZigBee payload, which can be compatible with standard ZigBee and only introduce negligible energy overhead. We further propose two design enhancements, cross-validation and reference chips calibration, to ensure the accuracy of PPM. Such a collision recovery of PPM reduces the retransmissions caused by collisions and eliminates the energy overhead of CSMA/CA simultaneously, facilitating the realization of green ZigBee. We have prototyped and evaluated PPM with USRP, showing PPM recovers the collided messages with bit-error-rates in the order of ${10}^{-6}$ , which is magnitudes lower than state-of-the-art methods. Experimental results show that PPM can achieve packet reception ratio more than 90% and less than 20 retransmissions in a concurrent transmission experiment with 400 packets resulting in negligible packet retransmission cost of energy.

Whitelisting Without Collisions for Centralized Scheduling in Wireless Industrial Networks

Industrial applications require more and more low-power operation and high-reliability (close to 100%). Since traditional low-power radio technologies are sensitive to external interference, many recent standards implement frequency hopping schemes. For instance, IEEE 802.15.4-2015 time slotted channel hopping (TSCH) relies on a deterministic schedule of data transmissions combined with a pseudo-random frequency hopping scheme to improve the reliability. Unfortunately, specific radio channels keep on increasing the average number of retransmissions. Using a subset of the best radio channels (whitelisting) helps to improve the reliability, but may create collisions when used improperly. We here investigate the most accurate techniques to use only the best radio channels while still providing deterministic performance. We propose to group the links per timeslot, allocating them either to the same whitelist or even appropriately reordering them to avoid collisions. Finally, we evaluate the performance of the different whitelisting schemes using an experimental dataset from FIT IoT-LAB platform, proving the relevance of such approach to improve the reliability.

An Improved Roadside Parking Space Occupancy Detection Method Based on Magnetic Sensors and Wireless Signal Strength.

Smart Parking Management Systems (SPMSs) have become a research hotspot in recent years. Many researchers are focused on vehicle detection technology for SPMS which is based on magnetic sensors. Magnetism-based wireless vehicle detectors (WVDs) integrate low-power wireless communication technology, which improves the convenience of construction and maintenance. However, the magnetic signals are not only susceptible to the adjacent vehicles, but also affected by the magnetic signal dead zone of high-chassis vehicles, resulting in a decrease in vehicle detection accuracy. In order to improve the vehicle detection accuracy of the magnetism-based WVDs, the paper introduces an RF-based vehicle detection method based on the characteristics analysis of received signal strengths (RSSs) generated by the wireless transceivers. Since wireless transceivers consume more energy than magnetic sensors, the proposed RF-based method is only activated to extract the data characteristics of RSSs to further judge the states of vehicles when the data feature of magnetic signals is not sufficient to provide accurate judgment on parking space status. The proposed method was evaluated in an actual roadside parking lot and experimental results show that when the sampling rate of magnetic sensor is 1 Hz, the vehicle detection accuracy is up to 99.62%. Moreover, compared with machine-learning-based vehicle detection method, the experimental results show that our method has achieved a good compromise between detection accuracy and power consumption.

6LoWPAN Fragment Forwarding

Low-power wireless technologies have been applied to industrial fields not only to monitor facilities but also to control them. There is a legitimate requirement to integrate low-power wireless networks with existing IP-enabled networks such as the Internet. The 6LoWPAN standard makes this happen easily by enabling low-power wireless networks to transport IPv6 packets. A challenge is that an IPv6 packet might not fit in a link-layer frame. The answer is fragmentation: the IPv6 packet is cut into fragments, each fitting in a frame. In a typical implementation, the IPv6 packet is fragmented and reassembled at every hop. Such per-hop reassembly causes low endto- end reliability and high end-to-end latency. This article presents a new implementation technique that results in fragment forwarding without changing any of the standards. Simulation results show how, when going from per-hop reassembly to fragment forwarding, end-to-end reliability goes from 40 percent to 100 percent, memory requirements go from 1280 B to 160 B, and end-to-end latency is halved.

Emerging applications through low-power wireless technologies for Internet of Things

Emerging applications through low-power wireless technologies for Internet of Things

Long-Range Low-Power Wireless Networks and Sampling Strategies in Electricity Metering

This paper studies a specific low-power wireless technology capable of reaching a long range, namely long range (LoRa). Such a technology can be used by different applications in cities involving many transmitting devices while requiring loose communication constrains. We focus on electricity grids, where LoRa end-devices are smart meters that send the average power demanded by their respective households during a given period. The successfully decoded data by the LoRa gateway are used by an aggregator to reconstruct the daily households’ profiles. We show how the interference from concurrent transmissions from both LoRa and non-LoRa devices negatively affect the communication outage probability and the link effective bit-rate. Besides, we use actual electricity consumption data to compare time-based and event-based sampling strategies, showing the advantages of the latter. We then employ this analysis to assess the gateway range that achieves an average outage probability that leads to a signal reconstruction with a given requirement. We also discuss that, although the proposed analysis focuses on electricity metering, it can be easily extended to any other smart city application with similar requirements, such as water metering or traffic monitoring.

Wireless mesh network data communications and reliability analysis for anti-theft application deployment in educational institutions

PurposeThe purpose of this study is to locally develop low-cost wireless mesh networks for reliable data communications to devices that prevent the theft of these devices in learning institutions of South Africa.Design/methodology/approachA network test-bench was developed where millions of packets were transmitted and logged between interconnected nodes to analyze the quality of the network’s service in a harsh indoor building environment. Similar methodologies in “big data” analysis as found in particle physics were adopted to analyze the network’s performance and reliability.FindingsThe results from statistical analysis reveal the quality of service between multiple asynchronous transmitting nodes in the network and compared with the wireless technology routing protocol to assess coverage in large geographical areas. The mesh network provides stable data communications between nodes with the exception of reliability degradation in some multi-hopping routes. Conclusions are presented to determine whether the underlining mesh network technology will be deployed to protect devices against theft in educational institutions of South Africa.Research limitations/implicationsThe anti-theft application will focus on proprietary firmware development with a reputable tablet manufacturer to render the device inoperable. Data communications of devices to the network will be monitored and controlled from a central management system. The electronics embedding the system-on-chip will be redesigned and developed using the guidelines stipulated by the chip manufacturer.Originality/valueDesign and development of low-cost wireless mesh networks to protect tablets against theft in institutions of digitized learning. The work presents performance and reliability metrics of a low-power wireless mesh wireless technology developed in a harsh indoor building environment.

Energy Depletion Attacks in Low Power Wireless Networks

Low Power Wireless (LPW) networks have recently been emerging as key candidates to offer affordable connectivity for the constrained devices in the Internet of Things (IoT). However, they also raise major security concerns due to the inherent security vulnerabilities of built-in communication protocols. By exploiting these flaws, an adversary can attack sensors or actuators in an LPW network and force them to execute energy-hungry tasks such as verifying unauthenticated garbage messages repeatedly. This attack, namely energy depletion attack (EDA), can drain the batteries of the devices rapidly and lead to soaring network-wide energy expenditure. Consequently, the offense can leave the victims disabled, and even shut down the whole network due to the battery exhaustion of all the devices. In this paper, we investigate existing studies and provide a systematic review of EDAs and defenses in LPW networks. Through this work, we conclude that most existing LPW technologies are vulnerable to EDAs. This paper also indicates the security challenges in LPW networks related to EDAs along with the potential research directions. While LPW technologies have already hit the market with the promising deployment schedules, our attempt can inspire the research community to enhance the security of underlying protocols that will shape the connectivity of billions of devices in the future IoT ecosystem.

Titkos üzenet száll a széllel! (IoT-ben használt vezeték nélküli adatátviteli technológiák összehasonlítása)

In this publication I present the most widespread wireless technologies in IoT. My research focuses on low-power wireless technologies, such as ZigBee, WiFi, LoRaWAN, and Bluetooth. The study classifies the protocols in terms of range, throughput, and available data rates. Provides a brief summary of the protocols under review. Graphically compare their properties.

Performance Evaluation of LoRaWAN for Green Internet of Things

LoRa is a long-range, low power and single-hop wireless technology that has been envisioned for Internet of Things (IoT) applications having battery driven nodes. Nevertheless, increase in number of end devices and varying throughput requirements impair the performance of pure Aloha in LoRaWAN. Considering these limitations, we evaluate the performance of slotted Aloha in LoRaWAN using extensive simulations. We employed packet error rate (PER), throughput, delay, and energy consumption of devices under different payload sizes and varying number of end devices as benchmarks. Moreover, an analytical analysis of backlogged and non-backlogged under slotted Aloha LoRaWAN environment is also performed. The simulation shows promising results in terms of PER and throughput compared to the pure Aloha. However, increase in delay has been observed during experimental evaluation.Finally, we endorse slotted aloha LoRaWAN for Green IoT Environment.

Modeling the Connectivity of Data-Channel-Based Bluetooth Low Energy Mesh Networks

Bluetooth Low Energy (BLE) has become one of the most popular low-power wireless technologies. While BLE was originally designed for star topology networks only, recent developments have focused on enabling mesh network topology support for BLE. An emerging category of BLE mesh network initiatives is based on routing data units over BLE data channels. This letter investigates the fundamental connectivity parameters of data-channel-based BLE mesh networks, such as the probability of no isolation of a node and network $K$ -connectivity. We provide an analytical model for both parameters which is validated by means of extensive simulations.