Search results for "Networking & Telecommunications"
showing 10 items of 962 documents
Integration of WiFi ToF Positioning System in the Open, Flexible and Adaptive WiSHFUL Architecture
2017
We integrate a prototypeWiFi Time-of-Flight (ToF) ranging and positioning system in the WiSHFUL software platforms and hardware radios for experimental prototyping. Users have access to ToF measurements as well as computed positions through unified programming interfaces that make possible to investigate innovative positioning and networking solutions. TRUE pub
Optimal Design of an X-Band, Fully-Coaxial, Easily-Tunable Broadband Power Equalizer for a Microwave Power Module
2020
A microwave power module (MPM), which is a hybrid combination of a solid-state power amplifier (SSPA) as a driver and a traveling-wave tube amplifier (TWT) as the final high power stage, is a high-power device largely used for radar applications. A gain equalizer is often required to flatten the TWT output power gain owing to its big gain fluctuations over the operating frequency range. In this paper, the design of an X-band, fully-coaxial, easily-tunable broadband power equalizer for an MPM is presented. The structure is composed of a coaxial waveguide as the main transmission line and a coaxial cavity loaded with absorbing material as a resonant unit. Sensitivity analyses of the attenuati…
Green Data Centres integration in smart grids: New frontiers for ancillary service provision
2017
Abstract The paper presents a study, conceived within the GEYSER FP7 co-funded European research project, on the ancillary services that Green Data Centres (GDCs) can provide, focusing, in particular, on spinning reserve. More in detail, the main contribution of the paper is to show how GDCs can be involved in the secondary frequency regulation process of a smart distribution grid, for contrasting the disturbing effects of unexpected variation of the energy production. With this aim, a real data centre, owned by Engineering S.p.A., is simulated as connected to the Medium Voltage IEEE 14-bus test grid where some RES-based generators are supposed to exist. Simulations are carried out in order…
Compliance of IEEE 802.22 WRAN for field area network in smart grid
2016
Distributed power system network is going to be complex, and it will require high-speed, reliable and secure communication systems for managing intermittent generation with coordination of centralised power generation, including load control. Cognitive Radio (CR) is highly favourable for providing communications in Smart Grid by using spectrum resources opportunistically. The IEEE 802.22 Wireless Regional Area Network (WRAN) having the capabilities of CR use vacant channels opportunistically in the frequency range of 54 MHz to 862 MHz occupied by TV band. A comprehensive review of using IEEE 802.22 for Field Area Network in power system network using spectrum sensing (CR based communication…
Strategies and Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer
2019
The continuous development of internet of things (IoT) infrastructure and applications is paving the way for advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Nodes (WSNs) able to collect and transmit data through wireless communication channels, while often positioned in locations that are difficult to access, is driving research into innovative solutions involving energy harvesting (EH) and wireless power transfer (WPT) to eventually allow battery-free sensor nodes. Due to the pervasiveness of radio frequency (RF) energy, RF EH and WPT are key technologies with the potential to power …
A Generalization of Girod's Bidirectional Decoding Method to Codes with a Finite Deciphering Delay
2012
Girod’s encoding method has been introduced in order to efficiently decode from both directions messages encoded by using finite prefix codes. In the present paper, we generalize this method to finite codes with a finite deciphering delay. In particular, we show that our decoding algorithm can be realized by a deterministic finite transducer. We also investigate some properties of the underlying unlabeled graph.
Financial Evaluation of SLA-based VM Scheduling Strategies for Cloud Federations
2017
In recent years, cloud federations have gained popularity. Small as well as big cloud service providers (CSPs) join federations to reduce their costs, and also cloud management software like OpenStack offers support for federations. In a federation, individual CSPs cooperate such that they can move load to partner clouds at high peaks and possibly offer a wider range of services to their customers. Research in this area addresses the organization of such federations and strategies that CSPs can apply to increase their profit.In this paper we present the latest extensions to the FederatedCloudSim framework that considerably improve the simulation and evaluation of cloud federations. These si…
Various Approaches to Early Contractor Involvement in Relational Contracts
2021
Abstract The main rationale for involving contractors is to apply collaboration to mitigate risk and to harvest opportunities to reduce cost and to increase the project owner’s value. In the paper we argue in the applied analytical model that there are four levels of early contractor involvement (ECI), which are 1) Preparation of the project (before sparking off competition); 2) During the procurement phase (development of what to build); 3) Project delivery model (before construction contract, but after the contractor and designers are selected); 4) Project delivery model (where involvement also continues in the execution phase). In the paper we argue that category 4 have the largest poten…
Backoff Hardware Architecture for Inter-FPGA Traffic Management
2017
International audience; Multi-FPGA platforms are considered to be the mostappropriate experimental way to emulate a large Multi-ProcessorSystem-on-Chip based on a Network-on-Chip. However, theuse of a Network-on-Chip in several FPGAs requires inter-FPGA communication links to replace intra-FPGA links betweenrouters. As the ratio of the logic capacity to the number of IOsonly increases slowly with each generation of FPGA, IOs inFPGA are becoming a scare resource. And as there are morerouters than IOs, using a Network-on-Chip requires sharinginter-FPGA links between routers, and sharing an external linkcan lead to bottlenecks. Here, we evaluate the inter-FPGA trafficmanagement using a backoff…
Distributions Frames and bases
2018
In this paper we will consider, in the abstract setting of rigged Hilbert spaces, distribution valued functions and we will investigate, in particular, conditions for them to constitute a "continuous basis" for the smallest space $\mathcal D$ of a rigged Hilbert space. This analysis requires suitable extensions of familiar notions as those of frame, Riesz basis and orthonormal basis. A motivation for this study comes from the Gel'fand-Maurin theorem which states, under certain conditions, the existence of a family of generalized eigenvectors of an essentially self-adjoint operator on a domain $\mathcal D$ which acts like an orthonormal basis of the Hilbert space $\mathcal H$. The correspond…