Practical Applications Of Wireless Sensor Networks Research Articles

Duty Cycle Scheduling in Wireless Sensor Networks Using an Exploratory Strategy-Directed MADDPG Algorithm

This paper presents an in-depth study of the application of Multi-Agent Deep Deterministic Policy Gradient (MADDPG) algorithms with an exploratory strategy for duty cycle scheduling (DCS) in the wireless sensor networks (WSNs). The focus is on optimizing the performance of sensor nodes in terms of energy efficiency and event detection rates under varying environmental conditions. Through a series of simulations, we investigate the impact of key parameters such as the sensor specificity constant α and the Poisson rate of events on the learning and operational efficacy of sensor nodes. Our results demonstrate that the MADDPG algorithm with an exploratory strategy outperforms traditional reinforcement learning algorithms, particularly in environments characterized by high event rates and the need for precise energy management. The exploratory strategy enables a more effective balance between exploration and exploitation, leading to improved policy learning and adaptation in dynamic and uncertain environments. Furthermore, we explore the sensitivity of different algorithms to the tuning of the sensor specificity constant α, revealing that lower values generally yield better performance by reducing energy consumption without significantly compromising event detection. The study also examines the algorithms' robustness against the variability introduced by different event Poisson rates, emphasizing the importance of algorithm selection and parameter tuning in practical WSN applications. The insights gained from this research provide valuable guidelines for the deployment of sensor networks in real-world scenarios, where the trade-off between energy consumption and event detection is critical. Our findings suggest that the integration of exploratory strategies in MADDPG algorithms can significantly enhance the performance and reliability of sensor nodes in WSNs.

SLUA-WSN: Secure and Lightweight Three-Factor-Based User Authentication Protocol for Wireless Sensor Networks.

Wireless sensor networks (WSN) are composed of multiple sensor nodes with limited storage, computation, power, and communication capabilities and are widely used in various fields such as banks, hospitals, institutes to national defense, research, and so on. However, useful services are susceptible to security threats because sensitive data in various fields are exchanged via a public channel. Thus, secure authentication protocols are indispensable to provide various services in WSN. In 2019, Mo and Chen presented a lightweight secure user authentication scheme in WSN. We discover that Mo and Chen’s scheme suffers from various security flaws, such as session key exposure and masquerade attacks, and does not provide anonymity, untraceability, and mutual authentication. To resolve the security weaknesses of Mo and Chen’s scheme, we propose a secure and lightweight three-factor-based user authentication protocol for WSN, called SLUA-WSN. The proposed SLUA-WSN can prevent security threats and ensure anonymity, untraceability, and mutual authentication. We analyze the security of SLUA-WSN through the informal and formal analysis, including Burrows–Abadi–Needham (BAN) logic, Real-or-Random (ROR) model, and Automated Verification of Internet Security Protocols and Applications (AVISPA) simulation. Moreover, we compare the performance of SLUA-WSN with some existing schemes. The proposed SLUA-WSN better ensures the security and efficiency than previous proposed scheme and is suitable for practical WSN applications.

RSS-Based DoA Estimation Using ESPAR Antennas and Interpolated Radiation Patterns

In this letter, it is shown how an algorithm, which employs received signal strength values in order to estimate direction of arrival (DoA) of impinging signals in wireless sensor network (WSN) nodes equipped with electronically steerable parasitic array radiator (ESPAR) antennas, can easily be improved by applying an interpolation algorithm to radiation patterns recorded in the calibration phase of the DoA estimation process. The proposed method allows one to measure ESPAR antenna's radiation patterns during the initial calibration phase with much coarser than 1° angular resolution, while the overall DoA estimation accuracy can be kept at the similar level. Measurements using a fabricated ESPAR antenna have indicated that anechoic chamber calibration procedure of WSN nodes equipped with such antennas can be done almost 50% faster, which in consequence will reduce system deployment costs in practical WSN applications where a number of WSN nodes can easily reach hundreds.

Optimizing the Reliability and Performance of Service Composition Applications with Fault Tolerance in Wireless Sensor Networks.

The services composition technology provides flexible methods for building service composition applications (SCAs) in wireless sensor networks (WSNs). The high reliability and high performance of SCAs help services composition technology promote the practical application of WSNs. The optimization methods for reliability and performance used for traditional software systems are mostly based on the instantiations of software components, which are inapplicable and inefficient in the ever-changing SCAs in WSNs. In this paper, we consider the SCAs with fault tolerance in WSNs. Based on a Universal Generating Function (UGF) we propose a reliability and performance model of SCAs in WSNs, which generalizes a redundancy optimization problem to a multi-state system. Based on this model, an efficient optimization algorithm for reliability and performance of SCAs in WSNs is developed based on a Genetic Algorithm (GA) to find the optimal structure of SCAs with fault-tolerance in WSNs. In order to examine the feasibility of our algorithm, we have evaluated the performance. Furthermore, the interrelationships between the reliability, performance and cost are investigated. In addition, a distinct approach to determine the most suitable parameters in the suggested algorithm is proposed.

An efficient two-factor user authentication scheme with unlinkability for wireless sensor networks

User authentication with unlinkability is one of the corner stone services for many security and privacy services which are required to secure communications in wireless sensor networks (WSNs). Recently, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs, and claimed that their scheme achieves identity and password protection, and the resiliency of stolen smart card attacks. However, we observe that Xue et al.’s scheme is subject to identity guessing attack, tracking attack, privileged insider attack and weak stolen smart card attack. In order to fix the drawbacks, we propose an enhanced authentication scheme with unlinkability. Additionally, the proposed scheme further cuts the computational cost. Therefore, the proposed scheme not only remedies its security flaws but also improves its performance. It is more suitable for practical applications of WSNs than Xue et al.’s scheme.

An advanced temporal credential-based security scheme with mutual authentication and key agreement for wireless sensor networks.

Wireless sensor networks (WSNs) can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs). Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.'s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users' attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.'s authentication scheme are left unchanged.

Design of a miniaturized patch antenna for easy deployment on metal surfaces

Wireless sensor network (WSN) has become a hot topic lately. By using WSN things that previously were difficult or impossible to measure has now become available. One of the main reasons using WSN for monitoring is to save money by cost optimization and/or increase safety by letting the user knowing the physical status of the monitored structure. This thesis considers four main topics, empirical testing of WSN in harsh environments, antenna designs, antenna measurements and radio environment emulation.The WSN has been tested in train environment for monitoring of ball bearings and inside jet engines to monitor strain of blades and temperatures. In total, two investigations have been performed aboard the train wagon and one in the jet engine. The trials have been successful and provide knowledge of the difficulties with practical WSN applications. The key issues for WSN are robust communication, energy management (including scavenging) and physical robustness.For the applications of WSN in harsh environments antennas has to be designed. In the thesis, two antennas has been designed, one for train environment and one for the receiver in the jet engine. In the train environment, a more isotropic radiation pattern is preferable; hence a small dual layered patch antenna is designed. The antenna is at the limit of being electrically small; hence slightly lower radiation efficiency is measured. For the WSN in the jet engine, a directive patch array is designed on an ultra-thin and flexible substrate. The thin substrate of the antenna causes rather lower radiation efficiency. But the antenna fulfils the requirements of being conformal and directive.In reverberation chambers are used to measure antennas, but there are difficulties to provide a realistic radio environment, for example outdoor or on-body. In this thesis, a large reverberation chamber is designed and verified. It enables measurement between 400 MHz and 3 GHz. Also, a sample selection method is designed to provide a post processing possibilities to emulate the radio environment inside the chamber. The method is to select samples from a data set that corresponds to a desired probability density function. The method presented in this thesis is extremely fast but the implementation of the method is left for future research.

Scale-free topology evolution for wireless sensor networks

Robustness is an important issue in Wireless Sensor Networks (WSNs). In this paper, two topology evolution models based on complex network theory are proposed. A bayesian game clustering algorithm is used to achieve a uniform clustering, and topology evolution is executed among cluster heads according to random walk. Residual energy, node fitness, node saturation and communication radius are considered in the processes of topology evolution. Simulation results show that network topologies formed by the models are more in line with the practical application of WSNs and have a good robustness in harsh environment.

Energy and distance adaptive clustering algorithm for 3D wireless sensor networks

How to use the limited energy of sensor nodes efficiently and evenly is a significant issue which needs an emphatic consideration in the research on wireless sensor networks (WSNs). After researching, we find some factors such as the residual energy of node, and the distance from node to base station (BS) are critical for the network lifetime. Further, combining with the practical application of WSN in three-dimensional space, this paper proposes a three-dimensional solution based on the energy and distance adaptive clustering (3DEDAC) algorithm. In the following simulation experiments, we compare the network lifetime of 3DEDAC with the reconstructive LEACH protocol’s from different aspects, and calculate the optimum cluster number of 3D space. These experiment results demonstrate the 3DEDAC algorithm has higher energy efficiency in different network conditions, and is more competent to prolong the network’s lifetime.

Integration of dispenser-printed ultra-low-voltage thermoelectric and energy storage devices

This paper reports on an integrated energy harvesting prototype that consists of dispenser-printed thermoelectric energy harvesting and electrochemical energy storage devices. Parallel-connected thermoelectric devices with low internal resistances were designed, fabricated and characterized. The use of a commercially available dc-to-dc converter was explored to step-up a 27.1 mV input voltage from a printed thermoelectric device to a regulated 2.34 V output at a maximum of 34% conversion efficiency. The regulated power succeeds in charging dispenser-printed, zinc-based micro-batteries with charging efficiencies of up to 67%. The prototype presented in this work demonstrates the feasibility of deploying a printable, cost-effective and perpetual power solution for practical wireless sensor network applications.

Scale-free topology evolution for wireless sensor networks with reconstruction mechanism

How to improve survivability of wireless sensor networks (WSNs) is an important issue which has attracted much attention over recent years. In this paper, by resorting to complex network theories, we propose two models, namely, a linear growth evolution model (LGEM) and an accelerated growth evolution model (AGEM). In the model evolution processes, the following factors: node addition, node deletion, and link reconstruction that naturally arise from practical WSNs applications are considered. In addition, accelerated growth is introduced into the evolving processes of AGEM. Theoretical analysis shows that AGEM is an extension of the LGEM model, and AGEM is generally more flexible and accommodating in practice. Simulation results show that the degree distributions of two models have scale-free characteristics and the topologies generated by the two models show a good survivability under random and deliberate attacks.

Implementation and application of a multi-radio wireless sensor networks testbed

The authors propose EasiTest, a multi-radio testbed for heterogeneous wireless sensor networks (WSNs). Two types of sensor nodes, specifically, high-speed multi-radio node (EZ271) and low-speed single-radio node (EZ521) are developed. An administration platform is provided to monitor and control the testbed. EasiTest enjoys high flexibility, powerful processing capability and ease of expansion. EasiTest provides a powerful tool not only for the study and evaluation of large-scale, heterogeneous sensor networks, but also for quick prototyping of practical WSN applications. To demonstrate the capability of the testbed, the co-existence problem of IEEE 802.11 and IEEE 802.15.4 is studied. Guidelines are given on channel allocation and network parameter configuration to minimise the interference. In addition, to demonstrate the flexibility of the testbed, the authors evaluate robust opportunistic scheduling for ad hoc networks, a distributed opportunistic scheduling protocol, based on the testbed. The experimental results match with the simulation results very well.