Improved LEACH protocol for increasing the lifetime of WSNs

Recently, wireless sensor network (WSN) is taking a high place in several applications: military, industry, and environment. The importance of WSNs in current applications makes the WSNs the most developed technology at the research level and especially in the field of communication and computing. However, WSN’s performance deals with a number of challenges. Energy consumption is the most considerable for many researchers because nodes use energy to collect, treat, and send data, but they have restricted energy. For this reason, numerous efficient energy routing protocols have been developed to save the consumption of power. Low energy adaptive clustering hierarchy (LEACH) is considered as the most attractive one in WSNs. In the present document, we evaluate the LEACH approach effectiveness in the cluster-head (CH) choosing and in data transmission, then we propose an enhanced protocol. The proposed algorithm aims to improve energy consumption and prolong the lifetime of WSN through selecting CHs depending on the remaining power, balancing the number of nodes in clusters, determining abandoned nodes in order to send their data to the sink. Then CHs choose the optimal path to achieve the sink. Simulation results exhibit that the enhanced method can decrease the consumption of energy and prolong the life-cycle of the network

Definition of an energy optimization protocol of a wireless sensor network

International audienceNowadays the WSN (Wireless Sensor Network) implemented in different domains such as environment, medical, military, etc. At the same time, the WSN has some limitations, among them and the major one is the energy resource and limitation in the battery's lifetime due to the fact of the small size of the sensor node. The clustering is the most efficient method for increasing the network's lifetime which most routing protocols based on it and LEACH (Low Energy Adaptive Clustering Hierarchy) are the first energy-efficient clustering hierarchical routing protocol. This clustering programs choose randomly the CH (Cluster Head) and just if the sensor node has a few energy. Thus in LEACH transmission, every CH sends data immediately to the BS (Base Station), so they consume more energy that decreases the network lifetime.In this paper, we propose a new approach based on LEACH protocol that purpose to extend the network's lifetime by balancing the energy of sensor nodes. Our model allows to chose CHs according to the current energy. Thus, data archives the BS by multi-hop method

An enhanced energy-efficient routing protocol for wireless sensor network

Recent few years, Wireless Sensor Network (WSN) has been an increasingly important technology that has been applied in almost all domains, even in complex environments where human activity is impossible. In WSN, various factors are impacted energy consumption, such as communication protocols, packet data transmission, and limited battery. So, the lifespan of the WSNs is limited. In this context, energy efficiency is the factor most attracted by many researchers. In this paper, we proposed a new improved LEACH routing protocol. This proposed protocol based on the current energy to select cluster-heads, and it uses a root cluster-head with more current energy and low distance to the sink to gather all data, then sends it to the sink. The simulation results in MATLAB confirmed that the proposed algorithm performed better than the conventional LEACH protocol, and increased the network lifetime in WSN

Genetic Algorithm based Model Predictive Control of Fractional Order Systems

International audienceFractional calculus is a generalization of integration and derivative operators to no integer order. In the Last decades fractional systems receives a great attention in the research community, the reason lies in the fact that many real systems can be described accurately using dynamic models of fractional order. In our work a design of genetic algorithm based fractional order model predictive controller is simulated and applied to a given fractional order model plant

Control algorithm for the urban traffic using a realtime simulation

Many types of research have been interesting by real-time control of urban networks. This paper, basing on a simplified urban traffic model, proposes a novel control approach based on model predictive control concept to reduce congestion and improve the safety of cars on the roads. The contributions of this paper are: First, we consider vehicle heterogeneity, represented by a mathematical model called “S Model” and integrate it with a realtime simulator to evaluate the performance of controllers on real traffic conditions. Second, in order to assess each controller's success under particular circumstances, the structured network-wide traffic controller based on model predictive control (MPC) theory is compared to a fixed time controller (FTC). Using two scenarios, different indicators are tested, i.e total time spent, vehicle number, queue length. The results show that the model predictive control quickly converges, with the different scenarios, and further improves social welfare

A 2.45/5.8 GHz high-efficiency dual-band rectifier for low radio frequency input power

This article proposes a concurrent rectifier for radio frequency (RF) energy harvesting from the popular ambient RF sources wireless fidelity (WiFi) 2.45 and 5.8 GHz bands. A voltage doubler-based converter circuit with the Schottky SMS7630 diode is used, this chosen diode has shown good results for low power levels. To ameliorate the resulting circuit, we used an interdigital capacitor (IDC) instead of a lumped component; and then we added a filter to reject the 3rd harmonics of each operating frequency. A dual-band impedance transformer with a direct current (DC) block function is used and optimized at low input power points for more harvested DC power. The final circuit was, therefore, more efficient and more reliable. The maximum conversion efficiencies obtained from the resulting circuit are about 60.321% for 2.45 GHz and 47.175% for 5.8 GHz at 2 dBm of input power. Compared to other previous rectifiers presented in the literature, our proposed circuit presents high efficiencies at low power levels and at these operating frequencies

Control du trafic urbain en temps réel

International audienceParallèlement au développement rapide des infrastructures de transport, les réseaux de transport deviennent plus vastes et plus complexes. En conséquence, les problèmes économiques et environnementaux deviennent plus importants. Afin de réduire les encombrements et d'améliorer la sécurité des voitures sur les routes, de nombreuses analyses et études ont été menées pour gérer les infrastructures existantes.Cette étude compare un contrôleur de trafic structuré à l'échelle du réseau basé sur la théorie de contrôle à retour d'état (SFC), qui représente un contrôle de modèle simplifié (modèle S) et le contrôleur à temps fixe (FTC).Ensuite, l'algorithme de contrôle basé sur le contrôle à retour d'état est présenté. Cet algorithme de contrôle est efficace et précis car il réduit le temps de calcul et utilise une méthodologie systématique pour contrôler les feux de signalisation multimodaux

The impact of noise on detecting the arrival angle using the root-WSF algorithm

This article discusses three standards of Wi-Fi: traditional, current and next-generation Wi-Fi. These standards have been tested for their ability to detect the arrival angle of a noisy system. In this study, we chose to work with an intelligent system whose noise becomes more and more important to detect the desired angle of arrival. However, the use of the weighted subspace fitting (WSF) algorithm was able to detect all angles even for the 5th generation Wi-Fi without any problem, and therefore proved its robustness against noise

How does technological parameters impact the static current gain of InP-based Single Heterojunction Bipolar Transistor?

In telecommunication systems, Heterojunction Bipolar Transistors (HBTs) are used extensively due to their good electrical characteristics. The work presented in this paper aims to enhance the electrical performance of the InP / InGaAs Single Heterojunction Bipolar Transistor (SHBT) in terms of the static current gain β. Silvaco’s TCAD tools were used for the simulation of the output characteristics of the studied electronic device. Initially, we used the interactive tool Deckbuild to define the simulation program and the device editor DevEdit to design the device structure, and we also used the simulator Atlas which allows the prediction of the electrical characteristics of most semiconductor devices. Because of several phenomena occuring within the electronic device SHBT, we added some physical models included in the simulator such as SRH, BBT.STD. Afterwards, we investigated the influence of doping concentrations of the base and the collector Nb and Nc on the electrical performance of the InP/InGaAs SHBT, and particularly in terms of the static current gain β. Finally, based on optimal values of the selected parameters, we have defined an optimized device that has a highest current gain β

La derivation non entiere reelle et complexe: synthese et applications dans les sciences de l'ingenieur

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 82909 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc