Статьи журнала - International Journal of Wireless and Microwave Technologies
Все статьи: 532
A Bayesian Belief Network Model For Detecting Multi-stage Attacks With Malicious IP Addresses
Статья научная
Multi-stage attacks are attacks executed in phases where each phase of the attack solely relies on the completion of the preceding phase. These attacks are so intelligently designed that they are able to elude detection from most network instruction detection systems and they are capable of penetrating sophisticated defenses. In this paper, we proposed and simulated a Bayesian Belief Network Model to predict Multi-stage Attacks with Malicious IP. The model was designed using Bayes Server and tested with data collected from cyber security repository. The model had a 99% prediction accuracy.
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A Circularly Polarized Planar Dipole with L-Shaped Metamaterial Radome for 5.8 GHz WLAN Application
Статья научная
A circularly polarized antenna based on a dual dipole topology is designed in this work. Circular polarization is achieved by placing two pair of parallel dipoles orthogonally and introducing a 90o phase difference between the four arms feeding the dipole using a phase shifter. The two arms of each dipole are located on the opposite sides of the single-layered substrate and fed using a probe feed. Disclosure to the environment can be negatively impact an antenna's radiation aspects and lead to greater. One way to protect these devices is to evaluate the proposed CP antenna with metamaterial radome design, which is closures that can shield antenna while improving the overall performance, by integrated with a metamaterial radome designed based on L-shaped unit cells. The application of this radome improved the impedance bandwidth from 3.9 % (without radome) to 6.3 % and the 3-dB axial ratio bandwidth from 3.2 % to 5.9 %. A prototype of the designed antenna structure is manufactured and measured. The designed and fabricated antenna has a simple structure and does not include disagreeable difficulty of the recently reported Complementary Cross-Dipole Antennas (CCDA). The antenna has a good radiation behavior in the improved desired gain of 4.31 dBi to at least 6.35 dBi due to the contribution of the radome. Design steps for achieving circular polarization and performance improvements are presented and validated experimentally using a fabricated prototype.
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Статья научная
We propose rate adaptation in the entire downlink process of transmission in channel-network combining coding systems. In current literatures, rate adaptation is discussed in channel coding or network coding separately and in traditional channel-network combining coding cases, network coding rates are generally 1. This paper is based on a one-source multi-destination wireless downlink communication system and a novel scheme of rate adaptation is applied. Our scheme of adaptation works between channel coding rate and network coding rate and its influence on system performance, which is given in form of simulation in the last chapter of this paper, shows that it works well for deducing system BER.
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A Compact Multiband U Shape MIMO Antenna for Wireless Application
Статья научная
A compact multiple-input-multiple-output (MIMO) antenna with two dual-branch U shape monopoles is proposed. The isolation between two antenna element is improve by adding three dumbbell shaped DGS between them. This antenna provides multiple frequency bands i.e. 2.4/5.8-GHz for WLAN, 2.5/3.5/5.5-GHz for WiMAX and 3.1–4.8 GHz for lower UWB band operation. The Antenna provides good results with Reflection coefficients < -15 dB and Transmission Coefficients < -30 dB. The results shows that the MIMO antenna can be serve as a phone antenna and it is suitable for integration within portable devices and handheld terminals with total maximum gain up to 4.5 dB and by combining all fields it provides total maximum gain up to 3.2 dBi.
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A Compact, Tri-Band and 9-Shape Reconfigurable Antenna for WiFi, WiMAX and WLAN Applications
Статья научная
This paper introduces a novel 9-shaped multiband frequency reconfigurable monopole antenna for wireless applications, using 1.6 mm thicker FR4 substrate and a truncated metallic ground surface. The designed antenna performs in single and dual frequency modes depending on switching states. The antenna works in a single band (WiMAX at 3.5 GHz) when the switch is in the OFF state. The dual band frequency mode (Wi-Fi at 2.45 GHz and WLAN at 5.2 GHz) is obtained when the switch is turned ON. The directivities are: 2.13 dBi, 2.77 dBi and 3.99 dBi and efficiencies: 86%, 93.5% and 84.4% are attained at frequencies 2.45 GHz, 3.5 GHz and 5.2 GHz respectively. The proposed antenna has VSWR< 1.5 for all the three frequencies. The scattering and far-field parameters of the designed antenna are analyzed using computer simulation technology CST 2014. The performance of the proposed antenna is analyzed on the basis of VSWR, efficiency, gain, radiation pattern and return loss.
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A Comparative Study of Data Collection Routing Protocols for Water Meter Reading Devices Network
Статья научная
This paper presents a comparative study of data collection routing protocols for the network of water meter reading devices. Water meters added with smart reading devices that could read the amount of water consumption and send it to the server via radio. Smart reading devices use a limited battery power source, therefore, it is necessary to employ energy-efficient data collection routing protocols to the network of water meter reading devices to increase network lifetime. CTP and RPL are two data collection protocols, which focused on research and evaluation in this paper. Simulation results in different channel quality conditions show that the RPL protocol achieves better energy efficiency than the CTP-0 and CTP-31 protocols. Although the successful data delivery ratio of RPL protocol is lower than that of CTP-31 protocol, data collected periodically in the network, so the loss of several data packets is acceptable.
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A Composite Heterostructure Mesh-shaped Patch Antenna Based on Left Handed Material
Статья научная
In this paper, a composite heterostructure mesh-shaped patch antenna based on left handed material (LHM) is presented. The method of finite difference time domain (FDTD) is used. The results show that electromagnetic wave resonance occurs near 4.52 GHz, where the equivalent permittivity and permeability of composite material are both negative. The composite antenna’s gain improves 9.047 dB, its return loss reduces 20.26 dB compared to the conventional antenna’s ones. The results indicate that this composite patch antenna system can reduce return loss of the antenna and increase the gain obviously.
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A Comprehensive Mechanism of MANET Network Layer Based Security Attack Prevention
Статья научная
The infrastructure benefits, which are achieved from the MANET architecture is the prime reason for the increase in usage for various purposes. The MANET architecture is made truly seamless with the capabilities of working without the central base stations or without the intervention of the central administration. The architecture for a MANET network is highly diversified and completely depends on the formation as the nodes in the MANET network can roam freely with a subsequent connection to any external device or any external networks. Yet another primary benefit of these devices and the networks are operability of the networks and the nodes without any human interventions. This property of the MANET network nodes makes the MANET devices operable in extreme conditions, where the human interventions are nearly impossible. In spite of these uncountable benefits, the MANET networks and the devices, which are part of the networkare always subjected to attacks from various sources. In this work, the attacks types for each network layer are identified and addressed to be prevented. The measures listed in this work are convertible as a modular component of any automated framework to make the complete attack prevention mechanism automated
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A Comprehensive Survey of Location Based Routing in Vehicular Networks
Статья научная
Vehicular network is the real time network formed by the highly dynamic nodes. This environment of VANET along with the fixed geographical mapping of roads slows down the delivery of the message in case of unicast and broadcast. When unicast is applied then the latency increases significantly as hop count increases. While broadcast make use of the network resources which degrades the performance by decreasing the efficiency of the network. However, multicast is proposed as the parameter to enhance the performance by introducing multicasting trees. This strategy is applied for maintaining the vehicular nodes in a multicast tree manner which will provide single path between two vehicles in the tree. Further, in case of the link failures, tree partitions and reconfiguration is needed this induces to have very low latency and reduces packet overhead. Various location based routing protocols are discussed which reveals different aspects and applications of variety of routing protocols relying on the location information.
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Статья научная
Rapid development of the multimedia and the associated technologies urge the processing of a huge database of video clips. The processing efficiency depends on the search methodologies utilized in the video processing system. Use of inappropriate search methodologies may make the processing system ineffective. Hence, an effective video retrieval system is an essential pre-requisite for searching relevant videos from a huge collection of videos. In this paper, an effective content based video retrieval system based on some dominant features such as motion, color and edge is proposed. The system is evaluated using the video clips of format MPEG-2 and then precision-recall is determined for the test clip.
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Статья научная
With the explosive growth of mobile applications and extensive praxis of cloud computing, mobile cloud computing has been introduced to be a potential technology for mobile services. But privacy is the main concern for a mobile user in the modern era. In the current study, we address the privacy challenges faced by mobile users while outsourcing their data to the service provider for storage and processing. However, a secure mobile user is required to protect these fundamental privacy factors such as their personal data, real identity, current location and the actual query sent to the cloud vendor server while availing different cloud services. Under these privacy metrics, we evaluated the existing approaches that are counting privacy challenge in mobile cloud computing. The primary focus of this study is to presents a critical survey of recent privacy protection techniques. Leading to objective, the current study conduct a comparative analysis of these state of the art methods with their strong points, privacy level and scalability. After analysis, this paper suggests the pseudo-random permutation method could be a promising solution that can be taken into consideration for preserving user personal information and data query privacy in MCC more efficiently. Primarily, the purpose of the survey was to focus on further advancements of the suggested method. Furthermore, we present the future research directions in the mobile cloud computing paradigms.
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A Data Flow Behavior Constraints Model for Branch Decision-making Variables
Статья научная
In order to detect the attacks to decision-making variable, this paper presents a data flow behavior constraint model for branch decision-making variables. Our model is expanded from the common control flow model, it emphasizes on the analysis and verification about the data flow for decision-making variables, so that to ensure the branch statement can execute correctly and can also detect the attack to branch decision-making variable easily. The constraints of our model include the collection of variables, the statements that the decision-making variables are dependent on and the data flow constraint with the use-def relation of these variables. Our experimental results indicate that it is effective in detecting the attacks to branch decision-making variables as well as the attacks to control-data.
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A Deep Analysis of Applications and Challenges of Wireless Sensor Network
Статья научная
Wireless sensor network refer to a community of a spatially dispersed and allocated sensors to track, record the enviromental physical conditions and to coordinate the collected information at a central point. WSN are becoming increasingly important with their wide range of business applications. WSN are being used in multiple fields such as health care, agriculture, systematic observation and condition based serviliance. WSN contain multiple sensors and because of features of implementing nodes, protection and authenticity, wireless sensor network become more complex. Security has drawn much attention in WSN in the last few years. But the transmission work done by sensors, is typically critical because there are large ammount of data and sensor devices are limited. Due to small number of sensers, the system is vulnerable to multiple attacks. The basic goal of this paper is to highlight the areas where the WSN is being used and multiple challenges to wireless sensor network. The multiple attacks and challenges to WSN are mentioned in this study. This research shows that although there are many challenges to WSN but still the use of wireless sensor network in multiple field such as agricultural and healthcare helps a lot to improve the efficiency, quality and performance of the those areas.
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A Deep Analysis of Image Based Video Searching Techniques
Статья научная
For many applications like brand monitoring, it’s important to search a video from large database using image as query[1]. Numerous visual search technologies have emerged with the passage of time such as image to video retrieval(I2V), video to video retrieval(V2V), color base video retrieval and image to image retrieval. Video searching in large libraries has become a new area of research. Because of advance in technology, there is a need of introducing the well established searching techniques for image base video retrieval task. The main purpose of this study is to find out the best image based video retieving technquie. This research shows the importance of image base video retrieving in the searching field and addresses the problem of selecting the most accurate I2V retrieval technique. A comparison of different searching techniques is presented with respect to some characteristics to analyze and furnish a decision regarding the best among them. The accuracy and retrieval time of different techniques is different. This research shows that there are a number of visual search techniques, all those techniques perform same function in different way with different accuracy and speed. This study shows that CNN is best as compare to others techniques. In future, the best among these techniques can be implemented to reduce the searching time and produce the promising result.
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A Density Control Algorithm For Wireless Sensor Network
Статья научная
If all nodes of a sensor network worked simultaneously, not only there would be a lot of redundant information, but also they would have great adverse impact on network throughput, bandwidth, latency, energy and network lifetime. Consequently, density control technology is necessary for sensor networks, because it can reduce the number of active sensor nodes under the precondition of ensuring network coverage and network connectivity. This paper proposes SNDC (Sensor Network Density Control), a location-free and range-free density control algorithm for wireless sensor network to keep as few as possible sensors in active state to achieve an optimal complete connected coverage of a specific monitored area by periodically sending three beacons of different transmission ranges. Inactive sensors can turn off sensing modules to save energy and sleep. Simulation results show that this algorithm can prolong the network lifetime and guarantee the small number of active nodes and complete network coverage.
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A Design Approach of GSM, Bluetooth and Dual band Notched UWB Antenna
Статья научная
In this paper, printed GSM Bluetooth dual band notch UWB antenna is presented. In this prototype corner cut patch for Bluetooth application and dual band notch characteristics of UWB antenna perform by inverting U- Slot in the radiation patch of antenna. With the enclosing of λ/4 stub in the patch of antenna for GSM (1.710-1.885 GHz) band operation. Simulation results show that the antenna yields an impedance bandwidth of 2.4-2.48 and 3-11 GHz with -10 dB reflection coefficients, except for the dual notched bands of 3.3-3.7 for Wi-MAX and 5.15-5.825 GHz for WLAN. The electrical characteristics in frequency domain show suitability of this antenna for use in UWB systems.
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A Design of Trust Degree Transfer Algorithm for P2P Network
Статья научная
The design of mechanism is used to calculate node reliability of incredible P2P network. The mechanism through matrix shows the trust relationship between nodes in the network, through matrix operation realizes the trust transfer process fast, and through a trusted server provides calculation service of trust degree for nodes in P2P network.
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A Discussion of a 60GHz Meander Slot Antenna for an RFID TAG with Lumped Element
Статья научная
In this paper, a novel approach to design an antenna for a transponder in radio frequency identification (RFID) is proposed. This approach is based on using a meander slot patch with a coplanar waveguide excitation (CPW). The RFID frequency chosen is the free 60 GHz band. The proposed circuit does not require complex package or bonding, thanks to the on-chip antenna, and it does not need battery. This technology is characterized by the low-cost, low-weight and low-area occupation. These particular specifications are important of this micro-RFID, especially if produced in large scale for the mass-market. Since the model of antennas in silicon technology is one of the main challenges, particularly for this proposal. The structure is simulated by using Computer Simulation Technology (CST). The antenna size is 1.95 * 1.99 mm2.This proposed antenna presents again which means a possibility to increase the readable range.
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A Group-oriented Access Control Scheme for P2P Networks
Статья научная
A group-oriented access control scheme is proposed for P2P (peer to peer) networks. In the proposed scheme, authentication control, admission control and revocation control are used in order to provide security services for P2P networks. Moreover, the proposed scheme can simply and efficient establish share key between two members without interactions, therefore it can perform secure communications with them. The analysis of security and performance shows that the proposed scheme not only can realize authentication and secure communication, but also can easily and efficiently add new group members and revoke malicious group members. Therefore, it is more efficient, and more practical protocol for P2P networks.
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A Hybrid Mimo Technique for Better Ber in High Data Rate Wireless Communication System
Статья научная
The need for high data rate and better quality of service in wireless communications has become imperative in the past few years judging by user demand. Obtaining these requirements has become very challenging for wireless communication systems due to the problems of channel multi-path fading, higher power and bandwidth limitations. One of the most promising solutions to this problem is the Multiple Input Multiple Output (MIMO) system. This paper proposed a combined spatial multiplexing MIMO scheme with beamforming for high data rate wireless communication. The proposed transmission scheme combines the benefits of both techniques resulting in the system ability to transmit parallel data streams as well as provide beamforming gain. Actually, these diverse techniques, share the same requirement of multiple antenna elements, but differ in the antenna element spacing necessary for the different schemes to work. Thus, smart antenna arrays were proposed as a possible solution and were adopted at both the transmitter and the receiver. The proposed hybrid technique provides better Bit Error Rate (BER) performance than the conventional MIMO, spatial multiplexing or beamforming technique alone under the same simulation environment.
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