Project and Realization of a Wide-Range High-Frequency RFID Gate Allowing Omnidirectional Detection of Transponders

The paper describes the study and development of a 2-meter-wide HF RFID gate providing omnidirectional detection of transponders.Common commercial HF RFID gate structures provide a maximum reading range around 150 cm.Moreover, this value is in most cases guaranteed only for the maximum coupling direction, with lower values for the other 2 orientations. The proposed structure raises the value of the reading range up to 200 cm for every orientation of the transponder, with even better results (220 cm) when the transponder is in the position of maximum coupling. This result has been achieved through numerical simulations, focused on the study of the geometry of the antenna system and on the realization of the matching circuit and then confirmed with the physical implementation of the system

RFID Applications for Sanitary Environments

Healthcare represents one of the most significant sectors where the diffusion of RFID technology is growing day by day. Many different applications have already been studied and developed, with both active and passive devices working at all the available operative frequencies. Sanitary environments are nowadays extremely complex structures employing several thousands of people with very strict safety requirements: in emergency situations for example 5 minutes can make the difference for a patient between survive and die. RFID is especially indicated to be employed in these scenarios for two main reasons: first of all because it’s a particularly reliable technology, with good performances, few errors and fast interaction, and secondly because, due to the presence of many different technological systems, ad-hoc solutions can be designed on the specific requirements of the application to be realized. At present the most common RFID applications in healthcare can be divided into two main categories: the items tracking and the tracking and identification of people, patients and sanitary operators. The items tracking is performed in order to avoid the loss of expensive devices and to reduce wasting of time during assistance operations: systems studied and realized for this purpose cover all the range of RFID systems and provide different services according to their different performances. RFID systems for the identification of people probably represent the most interesting sector, due to the variety of different applications that can be studied and realized. The most common systems foresee the use of RFID for the tracking of sanitary operators or patients during their assistance operations. Along with this many other applications have been implemented, including systems operating the unambiguous matching between the patient and his treatments (for example the medicine or the blood sack) or between the mother and the child in the paediatrics departments. Finally the availability of a memory on the transponders fostered to the use of RFID technology also as a mean to promptly store and retrieve patient related information: for example electronic case history or electronic medical prescription applications have been studied and developed

Interactive Digital Terrestrial Television: The Interoperability Challenge in Brazil

This paper introduces different standards implemented in existing Digital Terrestrial Television Broadcasting systems to allow the fruition of interactive services and applications through digital Set Top Boxes. It focuses on the interoperability issue between the Brazilian and the European architectures. In fact, despite in Brazil the GEM specification has been designed to foster wide content compatibility across a range of interactive platforms, it has never come to a final implementation and deployment. As a result the interoperability issue has been deeply explored in the BEACON project and an innovative system architecture has been developed to deploy t-learning services across Europe and Brazil, providing integration of those systems that were not able to interoperate until nowadays. This work is an important step in the direction of standards' interoperability. As a result, MHP and Ginga NCL-Lua implementation appeared to be the very best choice to deliver interactive services in an interoperable mode between European and Brazilian digital television

An ARQ Scheme with Memory and Soft Error Detectors

This paper describes a technique for increasing the efficiency of an ARQ communication system utilizing error detection codes. In this technique the blocks containing errors are not discarded at the receiver, as in the conventional ARQ systems. Such blocks are retained in order to make use of the information contained in them. A reliability value is associated to each demodulated symbol; this reliability value is updated every time a new retransmission is made, even if the vector received is in error. The process of updating the symbols often eliminates automatically the errors introduced by the channel. The results obtained by means of a simulation show that this method offers a considerable reduction in the average number of retransmissions, in comparison with conventional ARQ systems

Pre-processing and classification techniques of sar images for remote sensing applications

Dans cette communication,on décrit des techniques nu meriques pou le traitment des images et la classifica automatique des radars.Il aussi présenté d'abord les filtres numériques pour la reduction du bruit derivant des radars et,ensuite,des algoritmes utilisant la ré qle de Bayes ou la distance à blocs pour la classifi cation automatique des récoltes en agriculture. Les images à microondes,obtenues à travers des radars à ouverture synthétique et collectées pendant la campa gne europénne SAR 580,sont employées pou évaluer les performance des algoritmes qn question

Optimum structure of M-Ary modulated signals for error detecting codes

L'intégration de la modulation et de la codage de canal dans un système de communication a canal rétractif permit de méliorer les performances. Dans cette communication on analyse un nouvel méthode pou le combination de la codage de canal dans une modulation avec M symboles . Cette méthode gagnes meilleur performances relativement à semblables systèmes