Low-power Wireless Communication Research Articles

Energy-efficient and location-aware IoT and WSN-based precision agricultural frameworks

Precision agriculture has emerged as a promising approach to enhance crop yield, reduce environmental impact, and optimize resource utilization through advanced sensing and automation technologies. This paper proposes an energy-efficient and location-aware framework for Internet of Things (IoT) and Wireless Sensor Networks (WSN)-based precision agriculture systems. The framework leverages low-power wireless communication protocols, adaptive sensor scheduling, and location-based clustering algorithms to minimize energy consumption and prolong the network lifetime. Key features include real-time monitoring of soil moisture, temperature, humidity, and crop health through geographically distributed sensors, with automated decision-making for irrigation, fertilization, and pest control. The proposed framework also integrates machine learning models for predictive analysis and anomaly detection, enabling early identification of potential issues that could adversely affect crop productivity. Simulation results demonstrate a significant reduction in energy consumption and communication overhead, while maintaining high accuracy in environmental parameter monitoring and resource allocation. This framework offers a scalable and robust solution for implementing sustainable precision agriculture practices, particularly in remote and resource-constrained areas

Inner External DQN LoRa SF Allocation Scheme for Complex Environments

In recent years, with the development of Internet of Things technology, the demand for low-power wireless communication technology has been growing, giving rise to LoRa technology. A LoRa network mainly consists of terminal nodes, gateways, and LoRa network servers. As LoRa networks often deploy many terminal node devices for environmental sensing, the limited resources of LoRa technology, the explosive growth in the number of nodes, and the ever-changing complex environment pose unprecedented challenges for the performance of the LoRa network. Although some research has already addressed the challenges by allocating channels to the LoRa network, the impact of complex and changing environmental factors on the LoRa network has yet to be considered. Reasonable channel allocation should be tailored to the situation and should face different environments and network distribution conditions through continuous adaptive learning to obtain the corresponding allocation strategy. Secondly, most of the current research only focuses on the channel adjustment of the LoRa node itself. Still, it does not consider the indirect impact of the node’s allocation on the entire network. The Inner External DQN SF allocation method (IEDQN) proposed in this paper improves the packet reception rate of the whole system by using reinforcement learning methods for adaptive learning of the environment. It considers the impact on the entire network of the current node parameter configuration through nested reinforcement learning for further optimization to optimize the whole network’s performance. Finally, this paper evaluates the performance of IEDQN through simulation. The experimental results show that the IEDQN method optimizes network performance.

In-phase and quadrature frequency-shift keying for low-power optical wireless communications

This article proposes using in-phase and quadrature frequency-shift keying (IQFSK) modulation for low-power optical wireless communications (OWC). IQFSK independently leverages both cosine and sine basis functions to enhance the system’s spectral efficiency (SE). It uses only the odd harmonic frequencies for these basis functions, allowing the clipping of negative amplitude excursions without losing information, making the waveform compatible with OWC The work presents optimal maximum likelihood and low-complexity sub-optimal detection mechanisms for IQFSK. The proposed scheme is analyzed analytically and with numerical simulations. The simulation and analytical results indicate that the proposed scheme is more energy-efficient, can attain a better energy and SE trade-off by exploiting the frame structure of the waveform, and has a lower minimum squared Euclidean distance relative to other state-of-the-art FSK-based counterparts, thus establishing it as one of the most efficient FSK approaches for low-power OWCs.

Smart Wireless Transducer Dedicated for Use in Aviation Laboratories.

Reliable testing of aviation components depends on the quality and configuration flexibility of measurement systems. In a typical approach to test instrumentation, there are tens or hundreds of sensors on the test head and test facility, which are connected by wires to measurement cards in control cabinets. The preparation of wiring and the setup of measurement systems are laborious tasks requiring diligence. The use of smart wireless transducers allows for a new approach to test preparation by reducing the number of wires. Moreover, additional functionalities like data processing, alarm-level monitoring, compensation, or self-diagnosis could improve the functionality and accuracy of measurement systems. A combination of low power consumption, wireless communication, and wireless power transfer could speed up the test-rig instrumentation process and bring new test possibilities, e.g., long-term testing of moving or rotating components. This paper presents the design of a wireless smart transducer dedicated for use with sensors typical of aviation laboratories such as thermocouples, RTDs (Resistance Temperature Detectors), strain gauges, and voltage output integrated sensors. The following sections present various design requirements, proposed technical solutions, a study of battery and wireless power supply possibilities, assembly, and test results. All presented tests were carried out in the Components Test Laboratory located at the Łukasiewicz Research Network-Institute of Aviation.

Medical Data in Wireless Body Area Networks: Device Authentication Techniques and Threat Mitigation Strategies Based on a Token-Based Communication Approach

Wireless Body Area Networks (WBANs), low power, and short-range wireless communication in a near-body area provide advantages, particularly in the medical and healthcare sector: (i) they enable continuous monitoring of patients and (ii) the recording and correlation of physical and biological information. Along with the utilization and integration of these (sensitive) private and personal data, there are substantial requirements concerning security and privacy, as well as protection during processing and transmission. Contrary to the star topology frequently used in various standards, the overall concept of a novel low-data rate token-based WBAN framework is proposed. This work further comprises the evaluation of strategies for handling medical data with WBANs and emphasizes the importance and necessity of encryption and security strategies in the context of sensitive information. Furthermore, this work considers the recent advancements in Artificial Intelligence (AI), which are opening up opportunities for enhancing cyber resilience, but on the other hand, also new attack vectors. Moreover, the implications of targeted regulatory measures, such as the European AI Act, are considered. In contrast to, for instance, the proposed star network topologies of the IEEE 802.15.6 WBAN standard or the Technical Committee (TC) SmartBAN of the European Telecommunication Standards Institute (ETSI), the concept of a ring topology is proposed which concatenates information in the form of a ‘data train’ and thus results in faster and more efficient communication. Beyond that, the conductivity of human skin is included in the approach presented to incorporate a supplementary channel. This direct contact requirement not only fortifies the security of the system but also facilitates a reliable means of secure communication, pivotal in maintaining the integrity of sensitive health data. The work identifies different threat models associated with the WBAN system and evaluates potential data vulnerabilities and risks to maximize security. It highlights the crucial balance between security and efficiency in WBANs, using the token-based approach as a case study. Further, it sets a foundation for future healthcare technology advancements, aiming to ensure the secure and efficient integration of patient data.

Design and Implementation of a LoRa Technology - Based Smart Home Monitoring Circuit

This paper offers a detailed design and real-world execution of a complex electrical circuit for smart homes that employs LoRa technology to monitor significant environmental conditions and the operating state of home equipment. The circuit's novel design allows it to monitor power usage and the on/off state of home appliances, in addition to measuring temperature and humidity with extreme precision. With its reputation for long-range and low-power wireless communication, LoRa technology is used by the core microcontroller of the system, which also processes sensor data. This is why the system works particularly effectively in large residences where other wireless technologies would have trouble. The solution ensures consistent and dependable data transmission using LoRa, even in the face of the common architectural obstacles seen in residential environments. To facilitate data analysis and remote monitoring, an electrical circuit was made to be readily linked to a central hub for home automation. A comprehensive assessment procedure was used for implementation in different household environments to determine responsiveness, dependability, and user-centered design. The empirical findings demonstrate how well the circuit works to provide homes with practical advice on how to best regulate device use and optimize the interior temperature, which eventually improves comfort and energy efficiency. To achieve next-generation home automation systems, LoRa-based solutions are critical, and the article concludes by analyzing the consequences of this study on the future landscape of smart-house technologies.

RSSI-based fingerprint localization in LoRaWAN networks using CNNs with squeeze and excitation blocks

The ability to offer long-range, high scalability, sustainability, and low-power wireless communication, are the key factors driving the rapid adoption of the LoRaWAN technology in large-scale Internet of Things applications. This situation has created high demand to incorporate location estimation capabilities into large-scale IoT applications to meaningfully interpret physical measurements collected from IoT devices. As a result, research aimed at investigating node localization in LoRaWAN networks is on the rise. The poor localization performance of classical range-based localization approaches in LoRaWAN networks is due to the long-range nature of LoRaWAN and the rich scattering nature of outdoor environments, which affects signal transmission. Because of the ability of fingerprint-based localization methods to effectively learn useful positional information even from noisy RSSI data, this work proposes a fingerprinting-based branched convolutional neural network (CNN) localization method enhanced with squeeze and excitation (SE) blocks to localize a node in LoRaWAN using RSSI data. Results from the experiments conducted to evaluate the performance of the proposed method using a publicly available LoRaWAN dataset prove its effectiveness and robustness in localizing a node with satisfactory results even with a 30% reduction in both the principal component analysis (PCA) variances on the training data and the size of the original sample. A localization accuracy of 284.57 m mean error on the test area was achieved using the Powed data representation, which represents an 8.39% increase in localization accuracy compared to the currently best-performing fingerprint method in the literature, evaluated using the same LoRaWAN dataset.

An Intelligent Health Surveillance System: Predictive Modeling of Cardiovascular Parameters through Machine Learning Algorithms Using LoRa Communication and Internet of Medical Things (IoMT)

In several nations, the majority of heart attacks lead to fatality prior to patients receiving any kind of medical intervention. The traditional healthcare system is mostly passive, requiring patients to initiate contact with healthcare services independently. People often do not request the treatment if they are unconscious during a heart disease episode. The use of Internet of Medical Things (IoMT) methods offers significant advantages in addressing the issue of caring for patients with cardiac problems. These techniques may transform service delivery into ubiquitous and activate healthcare services. Low-cost remote monitoring systems are essential to implementing a widespread healthcare service. In this article, we proposed a cost-effective Personal Health Care Device(PHCD) based on the Internet of Things (IoT). The PHCD transmits user somatic signals to data acquisition devices using a LoRa (Long-range and low-power) wireless communication network. The received data is uploaded to the cloud using IoT platforms like Adafruit IO. Further, various Machine learning (ML) algorithms, Naïve Bayes, ANN, CNN, and LSTM, were applied to collected data to predict heart rate and SpO2 behavior. The performance results of different forecast models were compared to identify precise modeling and reliable forecasts to prevent emergency cardiovascular conditions.

Leakyscatter: Scaling Wireless Backscatter Above 100 GHz

The past decade has seen rapid innovations in the design and deployment of low-power wireless communication mechanisms. Among them, the backscatter technique has been shown to be promising as it reduces the required power budget by orders of magnitude. However, most existing backscatter architectures operate in the sub-6 GHz regimes with a few recent examples in the lower mmWave bands. Meanwhile, despite the fact that power consumption increases radically above 100 GHz, the spectral regime has gained a lot of attention due to its abundant available bandwidth for 6G and beyond. In this article, we discuss a first-of-its-kind architecture that allows ultra-wideband directional data backscattering above 100 GHz regime while drawing near-zero power from the mobile device.

Study on the wireless sensor networks routing for Low-Power FPGA hardware in field applications

Very intelligent compact sensors with low-power and inexpensive solutions have been created because of the industrial revolution and subsequent advancements in electrical technology and wireless communications. Modern innovative enhancements have been made for the utilization of small, low-price, and low-power wireless communication devices with fast processing capabilities. The sensor node communication and routing play a significant role in the configuration of a specific WSN environment. There are three types of WSN routing: proactive, reactive, and hybrid. DSDV and OLSR are two proactive routing technologies. AODV and DSR are reactive routing technologies. DSDV Routing requires a progress update of its routing tables even when the network is not in use, which uses battery power and generates negligible data. As a result, this protocol is inappropriate for networks that are both huge in scope and very dynamic. OLSR maintains track of all potential solutions in a routing table. The overhead from control messages rises as there are more mobile hosts. It requires more processing power than other protocols while looking for alternate routes. The DSR protocol relies on the minimal hop count parameter to pick the way without considering other parameters that impact routing algorithm performance, such as energy consumption, residual energy, and connection stabilities. The FPGA realization provides an ascendable computing environment for WSN planning in a specific region. The research articles emphasize the hardware chip simulation and analysis of these routing protocols which can be further applied for field applications and configuration The network performance is evaluated using several performance metrics such as throughput, control overhead, delay, packet delivery ratio, and power consumption. This study offers a key method for creating FPGA-based power estimation and verification models for a WSN planning environment.

Highly reliable integrated W-band transmitter based on an on-chip dual-mode DFB laser and cascaded microring modulators

We propose an integrated W-band transmitter enabled by an integrated dual-mode distributed feedback (DFB) laser and cascaded silicon photonic microring modulators for next-generation wireless communication. 10 Gb/s error-free intensity modulation and direct detection W-band transmission are achieved in experiments by using the dual-mode DFB laser and two free-running lasers. Moreover, we conduct an experiment of dual-carrier modulation based on cascaded microring modulators, achieving 3 dB signal-to-noise ratio improvement and better signaling integrity for wireless communication. The proposed photonic integrated W-band transmitter will be a viable solution for a high-speed and low-power wireless communication system.

MCST Scheme for UAV Systems over LoRa Networks

In recent years, low-power wide-area network (LPWAN) has received widespread popularity with long-range and wide-area communication at low power for the Internet of Things (IoT) systems. Among many vendors of LPWAN, long-range low-power wireless communications, also called LoRa, is one of the competing standards and is well known in both academia and industrial communities as an emerging research area. Among the LoRa applications, unmanned aerial vehicles (UAV) systems are emerging with the benefits of extended battery life and a long communication range. In this paper, we investigate the network capacity with the mixture of concurrent and sequential transmission (MCST) scheme over LoRa networks. From the simulation results, it can be seen that MCST is suitable for implementation in the LoRa network. Specifically, MCST can achieve higher throughput with low transmission latency and energy consumption compared to the existing CSMA approach LoRa MAC. Besides, we also propose a modified MCST over the LoRa (mMCST/LoRa) scheme to mitigate the transmission latency further. The simulation results reveal a better performance in terms of throughput, latency and energy consumption, regardless of the frame payload size and the number of nodes in the network.

Intrusion Detection in Wireless Body Area Network using Attentive with Graphical Bidirectional Long-Short Term Memory

Recently developed low-power networked systems, wireless communications, and wireless sensors have all contributed to the rise of Wireless Sensor Networks (WSNs) as a potentially useful tool in the medical field. Securing Wireless Body Area Networks (WBANs) is essential for their widespread use in healthcare environments because the data they send frequently includes private and confidential patient health information. The study's goal is to create a system for detecting intrusions in WBAN. To best identify attacks in such systems, we present a novel “Attention-based Bi-directional Long Short-Term Memory with Graph Construction” (ABL-GC) here. The suggested approach ensures that the intrusion detection system uses only the features essential to detect a given attack, reducing the processing complexity.

Design of a Reconfigurable Intelligent Surface- Assisted FM-DCSK-SWIPT Scheme With Non-Linear Energy Harvesting Model

In this paper, we propose a reconfigurable intelligent surface (RIS)-assisted frequency-modulated (FM) differential chaos shift keying (DCSK) scheme with simultaneous wireless information and power transfer (SWIPT), called RIS-FM-DCSK-SWIPT scheme, for low-power, low-cost, and high-reliability wireless communication networks. In particular, the proposed scheme is developed under a non-linear energy-harvesting (EH) model which can accurately characterize the practical situation. The proposed RIS-FM-DCSK-SWIPT scheme has an appealing feature that it does not require channel state information, thus avoiding the complex channel estimation. We further derive the closed-form theoretical expressions for the energy shortage probability and bit error rate (BER) of the proposed scheme over the multipath Rayleigh fading channel. In addition, we investigate the influence of key parameters on the performance of the proposed transmission scheme in two different scenarios, i.e., RIS-assisted access point (RIS-AP) and dual-hop communication (RIS-DH). Finally, we carry out various Monte-Carlo experiments to verify the accuracy of the theoretical derivation, illustrate the performance advantage of the proposed scheme, and give some design insights for future study.

Mid-wave infrared optical receiver based on an InAsSb-nBn photodetector using the barrier doping engineering technique for low-power satellite optical wireless communication.

This paper proposes a new nBn photodetector (nBn-PD) based on InAsSb with a barrier doping engineering technique [core-shell doped barrier (CSD-B) nBn-PD] for utilization as a low-power receiver in satellite optical wireless communication (Sat-OWC) systems. In the proposed structure, the absorber layer is selected from an I n A s 1-x S b x (x=0.17) ternary compound semiconductor. The difference between this structure and other nBn structures is the placement of the top and bottom contacts in the form of a PN junction, which increases the efficiency of the proposed device through the creation of a built-in electric field. Also, a barrier layer is placed from the AlSb binary compound. The presence of the CSD-B layer with the high conduction band offset and very low valence band offset improves the performance of the proposed device compared to conventional PN and avalanche photodiode detectors. By applying -0.1V bias at 125K, the dark current is demonstrated at 4.31×10-5 A/c m 2 by assuming high-level traps and defect conditions. Examining the figure of merit parameters under back-side illumination with a 50% cutoff wavelength of 4.6µm shows that at 150K, the responsivity of the CSD-B nBn-PD device reaches about 1.8A/W under 0.05W/c m 2 light intensity. Regarding the great importance of using low-noise receivers in Sat-OWC systems, the results indicate that the noise, noise equivalent power, and noise equivalent irradiance are calculated as 9.98×10-15 A H z -1/2, 9.21×10-15 W H z 1/2, and 1.02×10-9 W/c m 2, respectively, at -0.5V bias voltage and 4µm laser illumination with the influence of shot-thermal noise. Also, D ∗ obtains 3.26×1011 c m H z 1/2/W without using the anti-reflection coating layer. In addition, since the bit error rate (BER) plays an essential role in the Sat-OWC systems, the effect of different modulations on the BER sensitivity of the proposed receiver is investigated. The results represent that the pulse position modulation and return zero on-off keying modulations create the lowest BER. Attenuation is also investigated as a factor that significantly affects BER sensitivity. The results clearly express that the proposed detector provides the knowledge to achieve a high-quality Sat-OWC system.

Remote Monitoring and Control System of a Water Distribution Network using LoRaWAN Technology

The problems related to the proper management and control in the distribution of potable water affect environmental sustainability generated by leaks and breaks in the infrastructure, causing leaks and loss of water. According to reports from the National Superintendence of Sanitation Services of Peru, more than 50% of complaints about the water service are related to billing problems and water leaks. It is for this reason that technologies such as the Internet of Things technology contribute to generating solutions for the automatic acquisition of data in residences and houses. That is why this paper aims to use long-range and low-power wireless communication systems to improve the service-oriented to the control of the water distribution network, monitoring of vandalism, and detection of anomalous events, reducing response time and economic losses. The paper's development methodology considers the implementation of a water controller node with flow control sensors and solenoid valves and a gateway with Lora communication. In addition, a solenoid valve control circuit and a remote visualization and control system are implemented. The results indicate that the implemented nodes allow adequate monitoring and control in real-time of the water flow, contributing to the adequate management of its consumption and supporting the detection of anomalous events using a Web application.

A Survey on the Security Challenges of Low-Power Wireless Communication Protocols for Communicating Concrete in Civil Engineerings.

With the increase in low-power wireless communication solutions, the deployment of Wireless Sensor Networks is becoming usual, especially to implement Cyber-Physical Systems. These latter can be used for Structural Health Monitoring applications in critical environments. To ensure a long-term deployment, battery-free and energy-autonomous wireless sensors are designed and can be powered by ambient energy harvesting or Wireless Power Transfer. Because of the criticality of the applications and the limited resources of the nodes, the security is generally relegated to the background, which leads to vulnerabilities in the entire system. In this paper, a security analysis based on an example: the implementation of a communicating reinforced concrete using a network of battery-free nodes; is presented. First, the employed wireless communication protocols are presented in regard of their native security features, main vulnerabilities, and most usual attacks. Then, the security analysis is carried out for the targeted implementation, especially by defining the main hypothesis of the attack and its consequences. Finally, solutions to secure the data and the network are compared. From a global point-of-view, this security analysis must be initiated from the project definition and must be continued throughout the deployment to allow the use of adapted, updatable and upgradable solutions.

A Survey of Small, Low-Frequency Antennas: Recent designs, practical challenges, and research directions

Robust, secure, low-power wireless communications and networking are needed to support emerging applications in emergency and disaster response, robotics, autonomous vehicles, and the Internet of Things (IoT) in physically complex environments, such as indoor/outdoor, dense urban, and other challenging scenarios. These applications require a variety of wireless communications modalities, including high and very-high frequency (HF and VHF) bands. To effectively deploy compact wireless communications systems at these low frequencies, high-performance electrically small antennas (ESAs) are needed. In this article, we present a survey of state-of-the-art low-frequency ESAs, including passive resonant, tunable, multiband, and actively matched designs. While passive designs are subject to classic tradeoffs in size and efficiency, active and platform-integrated techniques offer potential performance-enhancing alternatives. And, though single ESAs tend to omnidirectional beam patterns, multiantenna arrays can achieve directionality, and designs include parasitic, biomimetic, and distributed approaches.

Automatic multi-weigh-station for assessing sheep liveweight in small flocks

Sheep liveweight is a vital physiological parameter to monitor as it is directly correlated with the animals internal energy balance. Increases in liveweight in mature sheep coincide with an increase in fat and protein tissue while weight loss denotes an inverse relationship. This relationship underscores appropriate pasture stocking rates, production outputs, the correct dosing of medicinal treatments for maintaining a healthy flock and finding target markets. The sheep production industry is yearning for an accurate platform to provide real-time and accurate liveweight measurements without extensive labour. The two main methods for measuring sheep liveweight include; static yard weighting, which while accurate is labour intensive, and walk-over-weighing — which has the advantage of autonomy but lacks accuracy and requires the flock to be trained. In this work we describe a custom platform that accurately measures the liveweight of up-to three sheep simultaneously while they drink or eat from a field trough. A plywood frame consisting of three separated static weigh platforms — each with two commercially available weigh bars — was constructed to fit along side a conventional 3 metre trough. These strain gauges plug directly into a custom circuit board with a Teensy 3.6 microcontroller connected to several Analog-to-Digital converters, SDI-12, I2C and OneWire interfaces for additional environmental/agricultural sensors — all powered by a commonly available 12 V lead–acid battery and commercial solar charger. The device can communicate over LoRaWAN — a long range, low-power wireless communication architecture — making it suitable for remote deployment on large farms where traditional 3/4G telecommunications are unavailable. Firmware on the device sends device status updates every 15 min and calculates/transmits liveweight parameters in real-time — as animals use the trough. Five untrained mature wethers were given access to the device over a period of 57 days. A total of 1149 weights were captured, of that 853 were automatically flagged as reliable using algorithms provided in this work — equating to ∼74% of the original dataset. This work aims to enable producers to a quantify the physiological state of their flock without extensive labour, acting to increase their available decision making information in regards to flock productivity, stocking rates and animal welfare.

Evaluating face stability in mountain tunnel excavation by inclination monitoring at the tunnel crown - Atoda tunnel case study

The authors have been developing a prediction method for changes of ground stiffness ahead of a tunnel face by monitoring inclination at the tunnel crown (along the face advance axis). During the Atoda tunnel construction project, inclination monitoring was conducted at measurement intervals of 10 m. This is the first tunneling project practically using the proposed method throughout the excavation length. There is used a newly developed tilt sensor equipped with a Low-Power and Wide-Area (LPWA) wireless communication system that collects inclination data and transmits it to a data gateway automatically. During excavation work zones of weathered and fractured tuff breccia were recognized; face instability and partial collapse were experienced at those locations, though tunnel deformation was generally no more than 10 mm. Inclination values had a tendency to decrease in tunnel advance direction before the face encountered the soft/weak weathered rock, verifying the effectiveness of the method for monitoring tunnel stability and safety.