Search results for "Telecommunication"
showing 10 items of 1769 documents
Manifold Learning with High Dimensional Model Representations
2020
Manifold learning methods are very efficient methods for hyperspectral image (HSI) analysis but, unless specifically designed, they cannot provide an explicit embedding map readily applicable to out-of-sample data. A common assumption to deal with the problem is that the transformation between the high input dimensional space and the (typically low) latent space is linear. This is a particularly strong assumption, especially when dealing with hyperspectral images due to the well-known nonlinear nature of the data. To address this problem, a manifold learning method based on High Dimensional Model Representation (HDMR) is proposed, which enables to present a nonlinear embedding function to p…
Adoption of Constrained Application Protocol
2016
Among billions of Internet enabled devices that are expected to surround us in the near future, many will be resource constrained, i.e., will have limited power supply, processing power and memory. To cope with these limitations, the Constrained Application Protocol (CoAP) has been recently introduced as a lightweight alternative to HTTP for connecting the resource limited devices to the Web. Although the new protocol offers solid technical advantages, it remains uncertain whether a successful uptake will follow, as it depends also on its economic feasibility for the involved stakeholders. Therefore, this paper studies the techno-economic feasibility of CoAP using a systematic methodologica…
Keynote talk 3: From basics to advanced modelling and simulation techniques for mobile radio channels
2011
From the earliest beginnings of mobile communications to the present time, there has always been a high demand for realistic mobile radio channel models. This demand is driven by the fact that channel models are indispensable for the performance evaluation, parameter optimisation, and test of mobile communication systems. Channel modelling and simulation techniques are therefore of great importance for electronics and telecommunication engineers who are involved in the development of present and future mobile communication systems. This presentation will start with a review of the basic principles of mobile radio channel modelling and gradually moves to more advanced modelling and simulatio…
Modeling and statistical characterization of wideband indoor radio propagation channels
2010
In this paper, we focus on the modeling of wideband single-input single-output (SISO) mobile fading channels for indoor propagation environments. The derived indoor reference channel model is based on a geometrical scattering model, which consists of an infinite number of scatterers uniformly distributed over the two-dimensional (2D) horizontal plane of a rectangular room. We derive analytical expressions for the probability density function (PDF) of the angle of arrival (AOA), the power delay profile (PDP), and the frequency correlation function (FCF). An efficient sum-of-cisoids (SOC) channel simulator will be derived from the proposed non-realizable reference model. It is shown that the …
Editorial Article for Open Journal of Antennas and Propagation
2013
Antennas help communicate the World. Antennas make possible that millions of people can watch the Champions League. Antennas allow the positioning of billions of vehicles around our planet. And they also allow handling vehicles through our neighbor planets. By propagating waves through antennas you can send huge amounts of data in milliseconds. Besides, you can also tell somebody that you love him or her. Antennas have allowed communicate the people in these places where cables cannot. But antennas are not only used for communication. Antennas can be used for heating food, for detecting people, for guiding vessels, for founding treasures, for monitoring breath, for harvesting energy and so …
Study of transmission parameters under controlled multipath environment using Rasp Pi3
2018
The evaluation of QoS in mobile multipath environments is an interesting topic in modern communications. The use of Raspberry Pi as a low cost microcomputer board developed in the United Kingdom by the Raspberry Pi Foundation can be helpful in onsite deployments. The Pi3 model has integrated WiFi and Bluetooth connectivity and also 4 USB ports to expand the device with all kinds of peripheral. Under the premise of offering the power of a computer at low prices, this device is one of the most affordable ways to have a particularly efficient and dynamic hardware accessible at a low price to develop a Wireless Sensor Netwok (WSN). The use of the Raspberry Pi3 permits the development of a power…
A new autonomous data transmission reduction method for wireless sensors networks
2018
International audience; The inherent limitation in energy resources and computational power for sensor nodes in a Wireless Sensor Network, poses the challenge of extending the lifetime of these networks. Since radio communication is the dominant energy consuming activity, most presented approaches focused on reducing the number of data transmitted to the central workstation. This can be achieved by deploying both on the workstation and the sensor node a synchronized prediction model capable of forecasting future values. Thus, enabling the sensor node to transmit only the values that surpasses a predefined error threshold. This mechanism offers a decrease in the cost of transmission energy f…
Wireless strain gauge network — Best-hall measurement case
2014
Wireless sensor networks can be used to perform structural monitoring. Strain gauges, which can be glued on or integrated to the observed material, are the most common nondestructive sensing elements for measuring surface strain. Wireless strain gauge measurement system makes strain measurements more flexible while opening new targets of application in addition to those that traditional wired strain measuring systems can offer. We have implemented a long term strain measurement in a PVC-covered hall using wireless sensor network. In this paper we evaluate the functionality and suitability of the developed wireless system for this kind of monitoring. The paper discusses the experiences gaine…
Parameter optimization for amplify-and-forward relaying systems with pilot symbol assisted modulation scheme
2009
Article published in the journal:Wireless Sensor Network Also available from publisher: http://dx.doi.org/10.4236/wsn.2009.11003 Cooperative diversity is a promising technology for future wireless networks. In this paper, we consider a cooperative communication system operating in an amplify-and-forward (AF) mode with a pilot symbol assisted modulation (PSAM) scheme. It is assumed that a linear minimum mean square estimator (LMMSE) is used for the channel estimation at the receiver. A simple and easy-to-evaluate asymptotical upper bound (AUB) of the symbol-error-rate (SER) is derived for uncoded AF cooperative communication systems with quadrature amplitude modulation (QAM) constellations. …
An Integrated Wireless Communication Architecture for Maritime Sector
2011
Published version of a chapter in the book: Multiple Access Communications. Also available from the publisher at http://dx.doi.org/10.1007/978-3-642-23795-9_17 The rapid evolution of terrestrial wireless systems has brought mobile users more and more desired communication services. Maritime customers are asking for the same, such as the concepts of “Broadband at Sea” and “Maritime Internet”. Quite a lot of research work has focused on the development of new and better maritime communication technologies, but less attention has been paid on interworking of multiple maritime wireless networks or on satisfying service provisioning. To address this, an integrated wireless Communication Architec…