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This article presents the latest status and achievements of the IEEE Communication Society (ComSoc) Standards for Dynamic Spectrum Access Networks (DYSPAN), formerly IEEE Standards Coordinating Committee 41, that develops standards in the areas of dynamic spectrum access, cognitive radio, interference management, coordination of wireless systems, advanced spectrum management, and policy languages...
Interest to biosensors employing surface or localized plamons is rapidly growing both in research and clinical application. Plasmon-based sensors offer extremely high sensitivity, only second to the optical detection techniques involving fluorescent labeling, but without the necessity to label the molecule. In particular, surface plasmon resonance (SPR) sensors have been already demonstrated suitable...
With the increasing focus on security in information systems, it is becoming necessary to be able to describe and compare security attributes for different technologies. Existing are well-described and comprehensive, but expensive and resource demanding to apply. The Security Evaluation for Compliance (SEC) model offers a lightweight alternative for use by decision makers to get a quick overview of...
OTA (Over-The-Air) system, which is one of the MIMO terminal evaluation methods, achieves real multipath fading environment around the measurement device, and it is currently being standardized. Fading emulator, one of MIMO-OTA measurement systems, can achieve the desired propagation environment around assessment area by radio waves radiated from a number of antennas placed on a circle around the...
Many wireless channels exhibit sparse multipath feature in practice. In this paper, we analyze the sparsity of sparse MIMO channel and the leakage effect with fixed Fourier basis in the spatial/angular domain. In order to enhance the sparsity of the MIMO angular channels we propose an optimized overcomplete Fourier basis dictionary, which is obtained by a sparsity criterion, to represent the signals...
This paper applies a divide-and-conquer approach to achieve confidentiality control in Cloud Computing. We sketch how a Redundant Array of Independent Net-storages (RAIN) for Cloud Computing can be designed using techniques originally intended for other purposes. The RAIN approach splits data into segments and distributes segments onto multiple providers. By keeping the relationships between the distributed...
Super-quasi-orthogonal space-time trellis codes (SQOSTTC) is a powerful code that provide full rate, full diversity and high coding gain for four transmit antennas. These codes, designed for flat fading channel combines set partitioning principle and a super set of quasi-orthogonal space-time block codes in a systematic way to provide full diversity and improved coding gain. In this paper, the performance...
This paper presents a novel steganographic schemes based on Discrete Fourier Transformation (DFT) and demonstrates the multimedia colour image authentication process in frequency domain for wireless communication(DFTMCIAWC). Authentication is done through embedding secrete message/image into the transformed frequency components of the source image at message originating node. The DFT is applied on...
MIMO is one of the important technologies in LTE, WiMAX and LTE-Advanced for improving spectrum efficiency. However, it is not easy to make a compact MIMO antenna for portable terminals, keeping high performance. One of the problems is mutual coupling among the antennas. This reduces the efficiency of the antenna. In this paper, a 3 dB hybrid is used to cancel the mutual coupling. This idea can be...
HAPS has cropped up as a neoteric technology in the wireless communications field in recent years. The straightforwardness with which HAPS gets along with a telephone network service provider or the Internet, has made it to a unique feature of future wireless networks. Most HAPS' criteria have been well circumscribed by the International Telecommunication Union (ITU) or subscribed to in World Radiocommunication...
The virtualization of physical infrastructure by designing and embedding overlay networks is becoming still more relevant in order to overcome the challenges in operators' networks and in the internet as a whole by better utilizing the available resources. In this paper we investigate how a framework for network properties can be used for the enhanced design of overlay networks. The framework includes...
In this paper, a simple broadband antenna in a compact size is firstly proposed. Antenna configuration and its characteristics such as VSWR, radiation patterns, and gain have been explored and discussed. The measured results illustrate that the proposed antenna offers a bandwidth of over 50% for VSWR less than 2. It also has high cross-polarization levels, and good gains — varying from about 0.5 dBi...
Regulators around the world are currently setting rules and requirements that will allow for mass-market access to TV White Spaces. It is expected that the opening of those frequency bands to the consumer market will lead to a dramatic increase of spectrum exploitation efficiency in highly appealing frequency bands: In Europe, the frequency bands between 470 MHz and 790 MHz are considered and the...
This paper addresses the issue of performance degradation of IR-UWB systems in presence of low resolution ADC. This is a part of a UWB Transceiver working at W-band in Line-of-Sight, so effects of multipath can be ignored. First of all, the paper derives the analytical expression of the BER of an IR-UWB system as a function of the number of quantization bits of the ADC. This model has been used to...
IoT is going to be an established part of life by extending the communication and networking anytime, anywhere. Security requirements for IoT will certainly underline the importance of properly formulated, implemented, and enforced security policies throughout their life-cycle. This paper gives a detailed survey and analysis of embedded security, especially in the area of IoT. Together with the conventional...
Wireless projection technology has made a quantum leap forward in terms of portability, ease of use, performance and functionality. Today, slide projectors have become a part of the wireless LAN, and the user planning to project his/her desktop is just one click away from projector. This makes the projector easily accessible similar to other wireless equipments like printer, scanner etc. available...
Security issues are paramount in wireless networks even more so than in wired networks. A particularly devastating attack in wireless networks is the wormhole attack, where two or more malicious colluding nodes create a higher level virtual tunnel in the network, which is employed to transport packets between the tunnel end points. These tunnels emulate shorter links in the network in which adversary...
Mobile Ad hoc Network (MANET) is set up with a group of mobile wireless nodes and is devoid of any dedicated routers or base stations. The wireless nodes move around freely and mutually cooperate with each other in routing and forwarding packets without the support of any fixed infrastructure or centralized administration. The topology is highly dynamic, making the routing procedure more difficult...
This paper describes the design and simulation of novel microwave patch type Minkowski planar fractal antennas using IE3D electromagnetic simulation software. The fractal structure is advantageous in generating multiple resonances or enhancing bandwidth. Fractal antenna is comprised of elements patterned after self-similar designs. Self-similarity of the fractal shape can be translated into its electromagnetic...
Radio spectrum is natural limited resource, which cannot be owned. Many new technologies are emerging which require spectrum for faster growth. ITU has projected that 1720 MHz spectrum will be required by the year 2020. Several services are knocking the door of telecom market but these promising services cannot be rolled out due to non-availability of spectrum. To meet this demand, spectrum should...
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