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Safety and non-safety application services require a guarantee of network performance, mostly in terms of throughput and packet collision. The current radio propagation path loss models use mean additional attenuation sophisticated fading model and do not consider the obstacle caused due to obstacles of vehicles in LOS of transmitting and receiving vehicles. This affects the attenuation signal at...
Information sharing is critical to multi-agent team for cooperative decision making in dynamic and partially observable environments. Other than building a full information coverage, if agents in a team can be self-directed to valuate a potential receiver and where to communicate, the coordination efficiency will be greatly enhanced. Although intensive studies of information valuation approaches have...
This paper presents a method for studying the performance of mode-stirrers used in Reverberation chamber (RC) by studying their Doppler spectrum obtained in free space or in RC. Indeed, a mode-stirrer must have the largest diffracting properties corresponding to a Doppler Spectrum as spread as possible. For this purpose, a simple analytical model is proposed in order to obtain the Doppler spectrum...
The problem of a signal source or a signal receiver localization from time difference of arrival (TDOA) measurements is a crucial issue in many applications appearing in the fields of navigation, surveillance or wireless communication. In this paper we present the algorithm for finding a mutual location of both sources and receivers when the position of none of them is known. We derive an inequality...
This work presents a real-time localization system developed for professional care givers to track residents of an aged care facility during their visits to a crowded, multi-story shopping mall. The proposed system consists of a Wi-Fi based self-localization platform integrated into a wheeled walking frame and an application installed in a hand-held tablet device for displaying the locations of walker...
Automatic Modulation Classification (AMC) has been deeply studied in the context of Cognitive Radio (CR) where it represents a required step between signal detection and demodulation. Several blind methods were proposed in the case of Additive White Gaussian Noise (AWGN) channels. In this context, Analytical Mth-Power nonlinear Transformation (AMPT) was especially studied to tackle the blind AMC of...
This work aims at understanding and evaluating the impact of using different path loss models in the optimization trade-off of small cell (SC) networks. In LTE-A, the more realistic propagation models are the more efficient the radio and network optimization becomes. In this work we compare four urban path loss models: the urban/vehicular and pedestrian test environment from the ITU-R M. 1255 Report...
The complexity and abstraction of the electromagnetic environment make the visual perception of the battlefield electromagnetic situation very difficult, which also highlights the importance of developing an integrated electromagnetic situation simulation system which integrates the electromagnetic environment visualization, the equipment interference analysis and the military action deduction. To...
Magnetic induction tomography (MIT) could be one of next generation imaging techniques, yet has many challenges in enhancing resolution and sensitivity. Currently, most developed MITs utilizes normal copper electromagnets (EMs) to generate excited magnetic field so that it could be low cost and compact in size but generates weak magnetic strength, difficult in analyzing objects. One of ways enhancing...
In the design and development of service oriented applications, service choreography models describe the interactions between services at different abstraction levels. These models are usually created and evolved independently by different stakeholders and consequently deviations occur among models such as message not received and incompatible behaviours. It is therefore crucial to detect and resolve...
In many CMOS analog/RF circuits, such as passive mixers or N-path filters, the transistor operates as a switch. Switching circuits often experience source-drain reversal, and most transistor models exhibit discontinuities in second and higher-order derivatives of the drain current around zero drain-source bias. This introduces fundamental challenges in performing third-order inter-modulation distortion...
Small unmanned aerial systems (UAS) require constant, safety-critical connectivity for telemetry, command-and- control, and collision avoidance. Today, dedicated, short-range pilot-to-aircraft links provide this connectivity for UAS operation. For UAS operating in fleets and beyond line-of-sight, a robust multi-transmitter network to provide connectivity over a wide area will be needed. However, networks...
NS3 is a widely used open source dynamic event driven simulator to test new ideas, algorithms and protocols for networks including LTE cellular systems as guided by 3GPP specifications. This paper presents an addition to the LTE module of NS3 by implementing a wrap around mechanism for the standard 19-site cluster. In the wrap around mechanism, the network is extended to include six additional copies...
A sequence diagram is one of UML models that are usually used within the analysis phase in software system development. Since generating such sequence diagrams is performed manually, automated or semi-automated support is beneficial in providing important and practical help. In this paper, a new semi-automated approach for generating sequence diagrams from user requirements written in Arabic is proposed...
Nowadays, high-bandwidth networks are easily accessible in data centers. However, existing distributed graph-processing frameworks fail to efficiently utilize the additional bandwidth capacity in these networks for higher performance, due to their inefficient computation and communication models, leading to very long waiting times experienced by users for the graph-computing results. The root cause...
Due to its mathematical tractability, the homogeneous Poisson point process (PPP) has been employed to model wireless networks and analyze their performance. The PPP has the fundamental property that in a network with n nodes, the n nodes are distributed independently from each other. As such the PPP is not a suitable model for many networks where there exists a repulsion among the nodes. In order...
Low-Power Wide Area Networks (LPWANs) are continuously gaining momentum as fundamental enablers of the Internet of Things (IoT) paradigm. These networks provide longrange coverage to end nodes, exploiting license-free frequency bands. The focus of this work is on one of the most prominent LPWAN technologies: LoRa™. We implemented a new ns-3 module to study the performance of a LoRa-based IoT network...
In most of the existing multi-proxy multi-signature (MPMS) schemes, the same proxy group is delegated the proxy right to sign by all the original members. Nevertheless, in many practical applications, original signer often demands to designate the proxy group in his own organization which is different from others'. It is seldom considered in the MPMS schemes. In this paper, we propose a MPMS scheme...
Mathematical modeling is an important approach for creating a parallel database management system that could efficiently use capabilities, provided by modern heterogeneous computational clusters, equipped with manycore coprocessors or GPUs. To this day, several models heterogeneous computational systems were proposed, but none of them is suited for modeling database processing. In this paper, we address...
In this paper, we present the far-field characterization of the antenna subsystem of the Eu:CROPIS (Euglena and Combined Regenerative Organic-Food Production in Space) satellite. Its specialty, in contrast to other satellite missions, is the spin-stabilization used in order to simulate the Moon and Mars gravitational fields for the biological on-board experimentation. Thereby, spin rates of up to...
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