Instituto Superior Técnico

About: Instituto Superior Técnico is a based out in . It is known for research contribution in the topics: Catalysis & Finite element method. The organization has 10085 authors who have published 30226 publications receiving 667524 citations. The organization is also known as: IST & Instituto Superior Tecnico.

Recent advances in IR-UWB transceivers: An overview

Abstract: Modern Ultra-Wide Band (UWB) regulations have recently been adopted worldwide allowing for unlicensed operation within 3.1 and 10.6 GHz, using an appropriate wideband signal format with a low Effective Isotropic Radiated Power (EIRP) level. UWB characteristics are suitable to transmit data using pulses instead of continuous-waves such as in narrowband radio links. It has the potential to be the right technology for high data-rate, low-power and short-to-medium range communication systems. We will focus on Impulse Radio-UWB (IR-UWB) systems and show their suitability for many different applications, including sensor networks, ad-hoc networks, cognitive radio, home networking, etc. We will also discuss the difficulties and challenges of designing IR-UWB systems. We present a tutorial overview of UWB regulations and usable signals. We present the existing standards and recommendations, and we review recently published results, highlighting trends in UWB transceiver power consumption and the impact of CMOS scaling on performance.

Ultra-Wideband Radio Signals Distribution in FTTH Networks

Abstract: The use of an ultra-wideband (UWB) radio technique is proposed as a viable solution for the distribution of high-definition audio/video content in fiber-to-the-home (FTTH) networks. The approach suitability is demonstrated by the transmission of standards-based UWB signals at 1.25 Gb/s along different FTTH fiber links with 25 km up to 60 km of standard single-mode fiber length in a laboratory experiment. Experimental results suggest that orthogonal frequency-division-multiplexed UWB signals exhibit better transmission performance in FFTH networks than impulse radio UWB signals.

Universal multimedia experiences for tomorrow

Abstract: The previous decade has seen a variety of trends and developments in the area of communications and thus multimedia access. While individual, isolated developments produced small advances on the status quo, their combination and cross-fertilization resulted in today's complex but exciting landscape. In particular, we are beginning to see delivery of all types of data for all types of users in all types of conditions. This article discusses the current status of universal multimedia access (UMA) technologies and investigates future directions in this area. Key developments and trends from the last few years have set the scene for ubiquitous multimedia consumption. In summary, these are: wireless communications and mobility; standardized multimedia content; interactive versus passive consumption; and the Internet and the World Wide Web (WWW).