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Nowadays wireless communication for rotating electrical machines is interesting for both real time monitoring and diagnosis purposes. However, the application of this technology can lead to some problems. In fact, in our paper, the experimental results of radio monitoring system are illustrated to prove that one of the major problems of these types of application is the big received power variation...
In this paper, we investigate the combination of Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation (OFDM/OQAM) with spread spectrum Code Division Multiple Access (CDMA) transmission scheme as an alternative to classical Multicarrier-CDMA (MC-CDMA) system over multipath fading channel. The performance of real CDMA-OFDM/ OQAM transmission system with Walsh Hadamard...
The increase of rate for cellular networks to satisfy subscriber is always topicality. The rate of LTE-Adv (Long Term Evolution-Advanced) considered weak by users at intensive applications bandwidth. In this paper, we propose a model of chain transmission for improved rate of LTE-Adv. To solve this problem, we use the couple of multiplexing/demultiplexing OFDM (Orthogonal Frequency Division Multiplexing)...
In this paper, we aim at presenting a detailed classification of the most known authentication protocols using quantum means with calculation of quantum communication complexity. The Quantum Key Distribution protocols were basically proposed to establish secret keys that will be used later for encrypting and decrypting messages. Practically, QKD protocols are vulnerable against the men-in-middle attack...
Nowadays, the development of e-health concept is offering various aspects. In this paper, we present a novel website architecture. Designed for an e-health platform based on a wireless sensor network (WSN), this website offers the ergonomic and multi-functions opportunity for an ambient intelligent hospital. It enables the management of patients' records, real time patient's state monitoring based...
Deployment of femto-cells underlaying the macro-cell has been proven to greatly improve the system capacity and the indoor coverage. However, to successfully deploy this heterogeneous network, the interference among the macro-cell and femto-cells, as well as the interference between femto-cells, which are respectively called cross tier and intra-tier interferences, must be mitigated. Cognitive radio...
Given the rapid progress in wireless devices and the serious demands of higher communication rate, future solutions for wireless networks have to deal with these needs. Proposed solutions must take into account the limited spectrum resource while keeping the energy efficiency. So, a typical processing will realize a balanced trade off: max-throughput/minenergy consumption. In this paper, our contribution...
Algebraic Space-Time Codes (ASTC) for MIMO systems are based on quaternion algebras. Thanks to their algebraic construction, the ASTC codes, called the golden codes, are full-rank, full-rate and have the non-vanishing determinant property. Proposed for MIMO flat fading channels, these codes can increase the spectral efficiency and enhance the coding gain. ASTC codes maintain their proprieties for...
In this contribution we study the challenging issue of WiMedia solution which the ability to support high data rate applications but is limited to three piconets simultaneously communicating in the same area. For this reason we analyze the suitability of Channel Division Multiple Access (ChDMA) approach for Multiband Orthogonal Frequency Division Multiplexing (MBOFDM) Ultra Wide Band (UWB) (MB-UWB)...
Relay assisted cognitive radio is a promising technology that allows wireless systems to sense the environment, learn from previous experience and improves spectrum utilization by allowing unlicensed users to access the licensed spectrum. Studies of cognitive radio were mostly assuming a perfect channel state information (CSI). This assumption is usually unrealistic in practice because of the feedback...
In this paper, we present a theoretical analysis of the impact of High Power Amplifier (HPA) Non-Linear Distortion (NLD) on the Bit Error Rate (BER) of multicarrier techniques. For the aim of this study, the Saleh's model was chosen for NL HPA. Two multicarrier schemes are considered: the classical Orthogonal Frequency Division Multiplexing (OFDM) and the Filter Bank based Multi-Carrier (FBMC). According...
This paper discusses the resource allocation problem in an uplink multi-cell OFDMA system. The classical LTE model considers two areas in the cell: the cell center and the cell border and divides the resources in four sets. The users in the cells center zones use the same subset of subcarriers whereas the users of the border zones use the remaining resources with a Fractional Frequency Reuse (FFR)...
In wireless mobile ad hoc networks, routing protocols use metrics to select the best routes. Metrics may reflect the quality of the wireless link and help to manage mobility. But, there is a delay between link quality measurements performed by the routing protocol and their instantaneous values. To compensate this delay, the idea is to anticipate the value of the metric a few seconds in advance. The...
The traditional Linear Minimum Mean Square Error (LMMSE) channel estimation technique costs O(N3) floating operations and O(N2) memory locations where N represents the channel autocorrelation matrix order. In this paper, we propose to study a fast LMMSE channel estimation technique for LTE Downlink systems based on a fast solver for linear system with displacement structure which is based on the application...
LTE is defined as the 4G generation network providing high data rates. Channel estimation is important in the wireless system conception. Classical LMMSE channel estimation techniques require 0(JV3) floating operations and 0(JV2) memory locations (N is the size of the channel autocorrelation). In this paper, we propose fast channel estimation techniques for LTE based on fast solver for linear Toeplitz...
With their very Algebraic-construction based on Quaternionic algebra, Algebraic Space Time Codes (ASTC), called the Golden codes, have a full rate, full diversity and non-vanishing constant minimum determinant for increasing spectral efficiency. They have also uniform average transmitted energy per antenna and good shaping, readily lend themselves to high data rate situations. In this paper, we first...
Many solutions to accurate localization in indoor environments are based on the combination of Channel Impulse Response (CIR), as fingerprinting, and Neural Networks (NN) technique. Suitable there is no theory to indicate the neural network structure for a given problem. It must be done only experimentally. Then, this paper aims to identify the neural network structure and the accompanied algorithm...
Adaptive HELLO Messages are generated according to the instantaneous energy level of the battery is proposed for PC-PRPMANet based routing protocol. The HELLO messages are used by routing protocol for neighborhood discovery. Energy levels of neighbor nodes are collected by adjusting the HELLO messages period. Using Topology Control messages, each node stores the energy level for each valid path. Then...
In this contribution, we study the performance analysis of the Multiband Orthogonal Frequency Division Multiplexing Ultra Wide Band (MBOFDM UWB) high data rate system. The major problem of the MBOFDM UWB high data rate system is the cohabitation of more than three piconets sharing the same group of subbands over the same channel. As an alternative way to enhance the spectral efficiency of MBOFDM UWB...
With the rapid development of network technology, Internet services has revolutionized form a simple text into a host text, audio, video and other streaming services. Technological advances of the Internet have allowed the development of new services like multipoint multimedia applications: long-distance education, IPTV, telemedicine, distributed interactive games and video-conferencing systems. In...
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