Статьи журнала - International Journal of Wireless and Microwave Technologies
Все статьи: 544
Luminous Intensity Control System Based on ZigBee Wireless Sensor Networks
Статья научная
This paper introduces an energy conservation luminous intensity control system based on ZigBee sensor networks for smart home. The study is conducted to reduce unnecessary energy consumption by changing the luminous intensity of white LED according to the light coming into the room. A detecting circuit connected to the pin of CC2430 is set on the working face to collect the real-time luminous intensity signal. Then the ZigBee module adjusts the PWM signal to drive the white LEDs aiming at keeping a fixed and appropriate luminous intensity (e.g. 500Lux). Meanwhile, it transmits the data to the ZigBee coordinator through ZigBee wireless network. The monitoring PC get the data through the serial communication interface and display the states of the lights. Administrators can turn on or off the lights by clicking on the screen. This system can realize monitoring and controlling all the lights wirelessly so that users can save a lot energy and staff members. The system has been proved to be effective and convenient.
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MANET testbed using raspberry PIs
Статья научная
Mobile ad-hoc networks (MANETs) are without any infrastructure and consists only of equal peers. This paper presents an empirical tests for MANET routing protocols. The testbed based on Linux platform installed in mobile computers. Some parameters are analyzed such as movement speed and the number of hops which impact on routing performance. The testbed consists of several Raspberry Pis (RPis) without the need for any central master device. For making the RPis mobile and independent of any fixed power sockets, each of them is powered by a battery. On the other hand, for the evaluation of the testbed, two routing protocols are chosen. The first protocol is called BABEL, which considered as a distance vector routing algorithm. The other one, the Optimized Link State Routing Protocol (OLSR) which considered as proactive routing protocol. The use case was a multi-hop download of files with different size. The aim is to evaluate how multiple hops influence the bandwidth and delay. The results show that OLSR performs better regarding the throughput. But Babel has less delay and faster regarding convergence.
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Статья научная
In the wireless sensor network, various sensor nodes are present that are used for the communication, sensing and computing. An external mobile sink is present which move around the grid that is used for the communication with the nodes directly which are present in the network. As we know that for formation of network we need to find the route between all the nodes coming in the network, for this purpose routing is done. Routing is defined as moving of information from source to destination. For efficient network the routing protocol that is used should consume less energy, and less distance. In the MVGDRA routing algorithm is proposed that use the mobile sink approach. The selection of cluster head is done on the basis of the weight values. By doing this cluster head will be selected on the basis of the energy means which node has highest energy appointed as cluster head that increases the stability of the network. And the event driven based strategy is used for the data transfer, the energy will be only released when it is required. The energy will not be released after each round. By this the energy consumption of the system decrease and the life time the network is increased. So this method is considered to be more efficient and better than the traditional methods of routing as the network performance is enhanced and its life time is increased. Simulation results show the comparison between the VGDRA and the MVGDRA.
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Machine Learning Algorithms for Detecting DDoS Attacks in Intrusion Detection Systems
Статья научная
In today's interconnected world, the threat of intrusion activities continues to rise, making it imperative to deploy effective security measures such as Intrusion Detection Systems (IDS). These systems play a vital role in monitoring network and system activities to identify unauthorised or malicious behaviour. The focus of this research is on evaluating the efficiency of different IDS in detecting anomalies in network traffic, specifically targeting Denial of Service (DDoS) attacks that exploit server vulnerabilities using IP addresses. The study utilises the CIC-DDoS 2019 dataset to analyse the performance of various IDS, particularly Network Intrusion Detection Systems (NIDSs), in predicting DDoS attacks accurately. To combat the diverse range of DDoS threats, a collective classifier is introduced, which combines four top-performing algorithms to enhance detection capabilities. By transforming the problem into a multilabel classification issue, the researchers aim to address the complexity of DDoS attacks effectively. Several machine learning (ML) and artificial intelligence (AI) algorithms are employed in the study, including Random Forest Classifier, Decision Tree Classifier, Support Vector Machine (SVM), Naïve Bayes, Multi-Layer Perceptron, Long Short-Term Memory (LSTM), and XGBoost Classifier. Evaluating the performance and computational efficiency of these algorithms is crucial to determining the most effective approach to detecting DDoS attacks. The results of the research highlight the effectiveness of the Random Forest Classifier and Multi-Layer Perceptron in accurately detecting DDoS attacks, as evidenced by their high accuracy rates on the test dataset. These findings underscore the importance of leveraging advanced ML algorithms to enhance the security of networks and systems against evolving cybersecurity threats. In conclusion, the study emphasises the significance of deploying robust IDS equipped with sophisticated ML algorithms to safeguard against intrusion activities like DDoS attacks. By continuously evaluating and improving the performance of these systems, organisations can enhance their cybersecurity posture and mitigate the risks posed by malicious actors in the digital landscape.
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Machine Learning Based Analysis of Cellular Spectrum
Статья научная
One of the key issues of wireless communication networks is the spectrum crisis, and studies noted that static licensed bands are in the under-utilization stage. Recently Cognitive Radio Network facilitates a solution to minimize the spectrum crisis in which unlicensed users can utilize the licensed spectrum without transmission interference. To achieve this task we used Machine Learning techniques for analyzing spectrum occupancy which is an efficient method to analyze spectrum occupancy and provides high accuracy. Supervised machine learning algorithms namely Logistic regression, K nearest neighbor, and Naive Bayes are used to classify a given frequency band. In this paper we collect spectrum samples of GSM 900, 1800, and 2100 bands using Rohde & Schwarz FSH6 Handheld Spectrum Analyzer for developing a dataset, using that dataset we trained the classifiers and analyze their classification performance accuracy. Results have shown the best performance on the validation and testing partition for various Unweighted Average Recall (UAR) of each classifier. Here the Logistic Regression classifier learns the best representation from their feature vector. This research is helpful to measure the spectrum occupancy of different static allocated licensed bands for 24/7. This will give better ideas about spectrum utilization, future spectrum allocation and comfort to serve more users in the limited spectrum. The occupancy measurements of current allocated spectrums can not only provide a convincing basis for making future spectrum allocation policies, but also provide technical support for the development of new communication technologies.
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Managing Big Data: A Step towards Huge Data Security
Статья научная
Big data management (BDM) is the administration, management and governance of large volumes of all types of structured, semi-structured and unstructured data. Big data management is a blend of old and new best practices, teams, data types, skills, and home-grown or industrial-built functions and methods. Big Data Management is at the genesis of massive change to technology that will spur massive societal and industrial change. In this paper, different key factors kept in mind while managing big data are discussed along with the process of managing data so that organisations can get secure and accurate data. Further different developers have introduced methods have also been discussed and with it the main tools used in management of Big Data are introduced in this paper. BDM is suffering from many issues in the world are also explained here. Big Data Management deals with the integration, manipulation, quality and governance and management of Big Data including the key factors- Volume, Velocity and Variety of Big Data.
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Matlab Simulink of COST231-WI Model
Статья научная
Simulink is the integrated environment of system modelling and simulation, which is being widespread used. This paper describes the MATLAB visual simulation of the propagation path loss model for telecommunication systems. We simulated the whole process of COST231-Walfisch-Ikegami model with high accuracy, built a visual simulation frame and the path loss curves are given. This method can be used in studying other propagation path loss models in propagation environments.
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Статья научная
An accurate MATLAB-based CAD algorithm for quickly designing microstrip-based stepped-impedance resonator (SIR) low-pass filter is reported. The algorithm uses a circuit-theory approach to implement speedy computations, compared to the time-consuming computations involved in using electromagnetic theory. The accuracy of the proposed algorithm is verified for two widely-different practical examples in the 0-4GHz frequency range, against results obtained using Ansoft/Ansys circuit simulation tool, and against results obtained using the 3D electromagnetic simulator HFSS. The agreement among the three sets of data is seen to be excellent for most cases, and is found to be practically acceptable in the worst-case.
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Статья научная
Real and imaginary parts of complex permittivity of Aviation Turbine Kerosine (Hydro-fined) JetA-1 and Aviation Turbine Kerosine (Copper-Sweetened) JetA-1 are measured over the wide frequency range 8-12 GHz using X-band rectangular cavity resonator. The measurement technique uses the cavity perturbation technique. The fuel sample is filled in thin capillary tube of low loss material. It is then inserted through a sample hole at the centre of the broader side of the waveguide cavity resonator. The sample shifts the resonance frequency. The resonance frequency and shift in resonance frequency are measured using PNA Network Analyzer (AT E8362C). Validity of present measurement technique has been checked by measuring the dielectric properties of well-known dielectric materials (Plexiglas). Due to lack of experimental data in literature on dielectric parameters of Aviation fuels, it would be of great interest for the community to find its dielectric properties over wider frequency range. In addition the estimation of measurement error associated with this technique is also discussed.
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Metamaterial Inspired Millimeter-Wave Antenna Arrays for 5G Wireless Applications
Статья научная
Fifth-generation (5G) wireless communication systems employ millimeter-wave (mm-wave) frequency bands to achieve a very broad spectrum for high data rate transmission. To meet the system requirements, the best design of antenna arrays with superior performance is essential. Thus, in this paper, the design and performance analysis of single element, 2 x 1, and 4 x 1 metamaterial inspired millimeter-wave antenna (MIA) arrays are proposed. The antenna elements are designed using Rogers’ 5880 as a substrate material with a 2.2 dielectric constant and thickness of 0.35 mm to operate at a center frequency of 38 GHz. The simulated design of the single, 2 x 1, and 4 x 1 MIA arrays return loss, bandwidth, gain, voltage standing wave ratio (VSWR), and total efficiency are: -82.95 dB, -67.1 dB, -69.12 dB; 1.971 GHz, 2.278 GHz, 4.704 GHz; 7.36 dBi, 9.11 dBi, 11.4 dBi; 1.001432, 1.0009, 1.0007; and 95.55 %, 94.01 %, 95.87. As compared to other works, improved performance has been achieved by considering the effect of meta-materials on the radiator and at the ground of microstrip patch antennas (MPA). The selected type of meta-materials alters the current distribution of the radiating patch that enhances the fringing fields at the edge of MPAs, which inspires the radiation of antennas and reduces the surface wave loss at the radiators’ ground plane. The proposed MIA antenna arrays have improved upon the drawbacks of traditional MPAs and fulfill the requirements of 5G communication systems.
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Methodologies, Requirements and Challenges of Cybersecurity Frameworks: A Review
Статья научная
As a result of the emergence of new business paradigms and the development of the digital economy, the interaction between operations, services, things, and software through numerous fields and communities may now be processed through value chains networks. Despite the integration of all data networks, computing models, and distributed software that offers a broader cloud computing, the security solution is have a serious important impact and missing or weak, and more work is needed to strengthen security requirements such as mutual entity trustworthiness, Access controls and identity management, as well as data protection, are all aspects of detecting and preventing attacks or threats. Various international organizations, academic universities and institutions, and organizations have been working diligently to establish cybersecurity frameworks (CSF) in order to combat cybersecurity threats by (CSFs). This paper describes CSFs from the perspectives of standard organizations such as ISO CSF and NIST CSF, as well as several proposed frameworks from researchers, and discusses briefly their characteristics and features. The common ideas described in this study could be helpful for creating a CSF model in general.
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Microstrip Dual-Band Bandpass Filter Fed with Lumped Capacitors
Статья научная
This paper presents a method of designing microstrip dual-band bandpass filter fed with lumped capacitors. Unlike the tapping or coupling feeding structures, the lumped capacitors could make the external quality factors have suitable values in two different pass bands. Thus no impedance transformers are needed when designing dual-band bandpass filter fed with lumped capacitors. An example of this kind of filter is designed, fabricated and measured. The measured results accord well with the simulated results, showing validity of the proposed method.
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Microwave Detection of Water Pollution in Underground Pipelines
Статья научная
An electromagnetic model is proposed to detect water pollution in underground pipelines. Contaminants present above a certain level in water can be a public health hazard. The contrast in the dielectric constant between contaminated and fresh water is one of the most important parameters to be considered for detecting the presence of pollutants in water. Simulations of frequency response and time domain pulse wave through a multi-layer medium are presented. The complex dielectric permittivity of polluted water has been measured as a function of frequency and analytically represented by Cole-Cole fit model. Water pollution can be detected by observing the variation of the reflection coefficient or reflected signals from unpolluted and polluted water. The experimental set up is described and the procedure followed to obtain an effective permittivity data is outlined. These measurements are, to the best of the author's knowledge, the first of its kind to be published. Microwave technique discussed in this manuscript for water pollution study is a pioneer technique to detect various pollutants in water.
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Статья научная
A miniaturized multiband planar monopole Ultrawideband (UWB) antenna is presented. The penta-band antenna is comprised of a: 3.1 – 10.6 GHz UWB band, 2.4 WLAN band, 1.8 GHz GSM band, 1.3 GHz GPS and a 0.95 GHz RFID band. The proposed UWB band is realized by using half of a conventional rectangular radiator size while the other half is used to realize the other bands by employing quarter wavelength U and G shaped strips called folded CLLRs (capacitively loaded loop resonators). The designed penta-band antenna has an overall size of 25 x 30 mm2. The measured and simulated results of the fabricated prototype are compared and satisfactory results are achieved.
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Mitigation of Byzantine attack using LSP algorithm in CR Networks through Blockchain Technology
Статья научная
In the past couple of years, the research on the Byzantine attack and its defense strategies has gained the worldwide increasing attention. In this paper, we present a secure protocol to escape from the Byzantine attack in the cognitive radio networks. This protocol is implemented using the Lamport-Shostak-Pease algorithm and blockchain technology. A reliable distributed computing system must be able to handle the faulty components to deliver the error less performance. These faulty components send the conflicting information to the other parts of the system. As a result, it creates a problem which is similar to the Byzantine Generals Problem (BGP). In order to design a reliable system, it is necessary to identify and overlook such faulty components. In the cognitive radio networks, there are the two types of users i.e. primary and secondary users. The primary users hold the licensed spectrum whereas the secondary users hold the leased spectrum. In these CR networks, there can be a similar problem like BGP while allocating the spectrum to the secondary users. Also, it requires all the users to agree on a common value, even with some faulty users in the network. This is called as the Byzantine Agreement. Here we have addressed this Byzantine General problem to develop a reliable and secure spectrum allocation using the Lamport-Shostak-Pease algorithm. It can solve the BGP for n≥3m+1 users in the presence of ‘m’ faulters. In this implementation, the blockchain technology is used as the efficient decentralized database which records all the transactions of the users, like exchanging currency, mining, updating the blockchain and auctioning the spectrum for lease.
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Mobile Antenna Inetvu 1800+ Series and its Implementation in Practice
Статья научная
Although fiber-optic communication is used by a large number of telecommunication companies, satellite technology has still its important place among communication technologies. This article focuses on mobile antenna InetVu 1800+ Series. Besides detailed description of hardware and software components, functionality testing and troubleshooting of the whole system are included as the important parts of the topic.
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Mobile Backhaul in Release 8 and Beyond: Benefits, Challenges, Market Status and Impact Analysis
Статья научная
The significantly increasing mobile capacity demand, the use of advanced techniques like enhanced multiple input multiple output to boost throughput, very high data rate, reliability, very low latency, long battery life, mobility, and to enable internet of things in 4G and 5G technologies, aggravate extreme backhaul requirements with respect to capacity, latency, availability, energy, and on the top of this, cost efficiency. However, it is challenging to get a complete one backhaul technology that can solve all problems of backhaul especially massive introduction of small cells in mind. To overcome various backhaul problems there are many backhaul solutions i.e. the use of diversified backhaul under different use cases provides cost efficient backhaul solution. This paper presents benefits, implementation challenges, and use cases of mobile backhaul in release 8 and beyond. It also presents coverage and capacity analysis using excel based dimensioning tool for a given sample area. Lastly the paper shows economic benefits of diversified backhaul for small and macro cells and high-level implementation strategy for the considered area.
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Mobile Sink Path Optimization for Data Gathering Using Neural Networks in WSN
Статья научная
Wireless sensor networks are being used for various applications for collection of heterogeneous data. Hotspot problem is major issue of concern that affects the connectivity of entire network along with decreasing lifetime of network. The focus in this paper is lies on optimizing the path followed by the mobile sink for collection of data. The proposed work aims at reducing the hotspot problem and increasing the lifetime. A trained neural network is used to select the best route to be followed by mobile sink. In the proposed work, the stop points are identified which allow the communication between the nodes and the movable sink. The experimental results of the work carried out show that tour length of the sink is greatly reduced and the network lifetime (number of rounds) is increased. Increased lifetime also handles the problem of hotspots.
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Mobility Aware Strategy for Geographical Routing Schemes in Underwater Acoustic Networks
Статья научная
In those last decades the Underwater Wireless Sensor Network (UWSNs) have become the commonly explored technology by the scientific community, for the numerous benefits that it can brings to the researchers, however the frequent movement of the underwater sensors due to their mobility or water current factor may severally affect the efficiency of the acoustic wireless communication and reduce it performance. In this paper a Mobility Aware Strategy for Geographical Routing scheme (MAGR-VBF) has been proposed for an early prevention from the mobile sensor during the packet transmission, the protocol is aimed to predict the mobility and switch to another candidate sensor enable to recover the data packet in order to mitigate the packet loss problem. Based on the well-known routing protocol for the UWSNs ‘Vector Based Forwarding’ (VBF) the proposed study has been implemented and designed using the NS-2 simulator and Aqua-Sim. The result has shown that the presented work (MAGR-VBF) has brings a good performance over the basic VBF, where the energy consumption and the average end to end delay have been reduced by 8.97 % and 5.55 % respectively, and an average of 6.16 % has been increased of packet delivery ratio metric.
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Modelling Failure Conditions in Zigbee based Wireless Sensor Networks
Статья научная
Reliable data transmissions in sensor networks are important for its longevity and require research attention. Since, fault tolerance and reliability become vital for embedded systems, estimating failure scenarios aid WSN applications to establish robust backup mechanisms in case of failures in the network. The article aims to model failure in IEEE 802.15.4 Zigbee networks in order to estimate the longevity of the network in context to the network connectivity. Ideally, IEEE 802.15.4 can manage two types of networks, the star topology or the peer-to-peer topology. On combining these two we get a mesh network. Hence, the article presents the failure conditions for both star and mesh based network topology to the point where the network is disconnected owing to varied failure conditions.
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