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Network performance anomalies can be defined as abnormal and significant variations in a network's traffic levels. Being able to detect anomalies is critical for both network operators and end users. However, the accurate detection without raising false alarms can become a challenging task when there is high variance in the traffic. To address this problem, we present in this paper a novel methodology...
4G Long Term Evolution (LTE) mobile system adopts Adaptive Modulation and Coding (AMC) as a link adaption mechanism that is based on the User Equipment (UE) periodically reporting channel condition summarised through Channel Quality Indicator (CQI) which, in turn, is based on Signal-to-Interference-plus-Noise Ratio (SINR) and Reference Signal Received Power (RSRP). Although CQI has a predominant role...
Our daily life is characterized by countless human relationships. Every day we go to work, do shopping, partake in leisure time. At the base, there are some choices that lead us to make a series of activities; In which we interact and relate with many people. What influences the choices we make? Answering this question can be a very daunting task. However, it can help us to identify the main key elements...
In the touristic field, the trip is defined as the set of goods and services used by the traveler; Is organized by a manufacturer (tour operator) who designs and builds a reference path consistent with customer demand. Designing an itinerary is, therefore, a complex task because many variables need to be considered. It should be emphasized that each route has to change depending on the user's characteristics...
Internet of Things (loT) aims at collecting data from billions of devices connected altogether. Despite there is no one technology able to cope with all possible scenarios, LPWAN solutions are emerging as viable technologies for implementing private, low-cost cellular like wireless networks. Distributed systems could leverage this approach as a driving technology for services as smart environment...
The distributed control of islanded AC microgrids is based on the local measurements of the electrical variables at some nodes of the system to perform the secondary control. The Phasor Measurement Units (PMUs) guarantee accurate synchronized measurements that can be used as input signals for such distributed controllers. This paper analyzes the effect of one of the characteristic parameters of the...
In both wired and wireless networks, time synchronization is an important service for a wide range of applications in distributed systems. This includes radio interferometry. However, literature researches show that many distributed protocols cannot satisfy sub-ns time synchronization accuracy due to asymmetric delay errors, accumulated jitters and because of the strategy used to compute and adjust...
The aim of this paper is to introduce the measurement method for challenging Non-Line of Sight (NLOS) conditions in mobile networks. The need to develop the measurement method appeared LTE (Long Term Evolution) uplink (UL) performance with different antenna technologies when receiving NLOS signal in field tests. Many challenges appeared during the study. This paper introduces the challenges and presents...
This work deals with a measurement procedure for a fast and low-cost characterization of antennas for "Appareil de Recherche de Victimes d'Avalanches" (ARVAs). ARVA antennas are usually simple coil antennas tuned at 457 KHz. Such a low frequency ensures robust signal detection even in extremely harsh conditions, i.e. when the transmitter is buried under meters of snow and debris. Till now,...
In this paper, we present a framework for indoor positioning and navigation purposes. This framework uses crowd-sourced OpenStreetMap (OSM) data for rendering combined outdoor and indoor maps, for the calculation of navigation routes as well as for the correction of indoor positioning algorithms. Based on six general requirements, which we formulate and explain in this paper, the architecture and...
This paper presents the design technique of the selection diversity combining based spectrum sensing in cognitive radio networks. In general, the selection diversity combining scheme requires period to choose an optimal element, and spectrum sensing also requires period to detect a target signal. Because spending a long time for the selection and sensing increases the accuracy of the selection and...
Interactive and multimedia applications depend on the stability of end-to-end paths on the Internet for predictable performance and good quality of service. On the other hand, network providers depend on multiple paths to ensure fault tolerance and use load balancing between these paths to enhance the overall network throughput. In this study, we analyze the path dynamics within service providers'...
This work concerns the development of an efficient near-field/far-field (NF/FF) transformation technique with spherical spiral scanning suitable for an offset mounted quasi-planar antenna. Such a NF/FF transformation, relying on the nonredundant sampling representations of electromagnetic fields, requires practically the same number of NF data both when the antenna under test (AUT) is onset and offset...
Web tracking is currently recognized as one of the most important privacy threats on the Internet. Over the last years, many methodologies have been developed to uncover web trackers. Most of them are based on static code analysis and the use of predefined blacklists. However, our main hypothesis is that web tracking has started to use obfuscated programming, a transformation of code that renders...
The advances in wireless low-power sensors and the increasing demand for portable healthcare monitoring systems have inspired the realization of Wireless Body Sensor Networks (WBSNs). IEEE Std. 802.15.6 defines the communication protocol for WBSN applications in terms of physical and medium access layers. The high generality and flexibility of standard requirements poses the question of how WBSN parameters,...
In this paper, we discuss the upcoming network stack LoRaWAN and its underlying modulation technology LoRa, which is an implementation of a LPWAN (Low Power Wide Area Network) and consider practical limitations that can occur when restricted Machine-to-Machine (M2M) data agreements for the connection of LoRa gateways to a cellular network are involved. We provide a theoretical estimate of the maximum...
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