705 resultados para Mobile Handsets


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A practical, small-size, dual-helical antenna array mounted on a mobile handset model is designed for use as diversity/MIMO receiving antennas. The array is rigorously studied with respect to its diversity performance and the achievable channel capacity. It is found that a very low correlation coefficient, a high diversity gain, an equal-mean branch SNR, and a relatively matched input impedance can be achieved at the same time. It is shown that, at a remarkably small antenna separation (similar to 0.05 lambda), the signal correlation can be reduced to nearly zero, an almost ideal independent operation of the diversity antennas. The increase in MIMO channel capacity is 100% over a single antenna system. Both measured and simulation results are presented.

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The big proliferation of mobile communication systems has caused an increased concern about the interaction between the human body and the antennas of mobile handsets. In order to study the problem, a multiband antenna was designed, fabricated and measured to operate over two frequency sub bands 900 and 1800 MHz. After that, we simulated the same antenna, but now, in the presence of a human head model to analyze the head's influence. First, the influence of the human head on the radiation efficiency of the antenna has been investigated as a function of the distance between the head and the antenna and with the inclination of the antenna. Furthermore, the relative amount of the electromagnetic power absorbed in the head has been obtained.

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The big proliferation of mobile communication systems has caused an increased concern about the interaction between the human body and the antennas of mobile handsets. In order to study the problem, a multiband antenna was designed, fabricated and measured to operate over two frequency sub bands 900 and 1800 MHz. After that, we simulated the same antenna, but now, in the presence of a human head model to analyze the head's influence. First, the influence of the human head on the radiation efficiency of the antenna has been investigated as a function of the distance between the head and the antenna and with the inclination of the antenna. Furthermore, the relative amount of the electromagnetic power absorbed in the head has been obtained. In this study the electromagnetic analysis has been performed via FDTD (Finite Difference Time Domain).

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There is growing interest in the ways in which the location of a person can be utilized by new applications and services. Recent advances in mobile technologies have meant that the technical capability to record and transmit location data for processing is appearing in off-the-shelf handsets. This opens possibilities to profile people based on the places they visit, people they associate with, or other aspects of their complex routines determined through persistent tracking. It is possible that services offering customized information based on the results of such behavioral profiling could become commonplace. However, it may not be immediately apparent to the user that a wealth of information about them, potentially unrelated to the service, can be revealed. Further issues occur if the user agreed, while subscribing to the service, for data to be passed to third parties where it may be used to their detriment. Here, we report in detail on a short case study tracking four people, in three European member states, persistently for six weeks using mobile handsets. The GPS locations of these people have been mined to reveal places of interest and to create simple profiles. The information drawn from the profiling activity ranges from intuitive through special cases to insightful. In this paper, these results and further extensions to the technology are considered in light of European legislation to assess the privacy implications of this emerging technology.

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2000-luvun vaihteessa paikkatietoa hyödyntävistä matkapuhelinpalveluista odotettiin muodostuvan eräs merkittävimmistä kilpailuvalteista eri matkapuhelinoperaattoreiden välillä. Kiinnostusta paikkatietoa hyödyntäviin palveluihin lisäsi kaupallisten sovellusten lisäksi Yhdysvaltojen liittovaltioiden liikenneministeriön säätämä laki, joka velvoittaa paikantamaan yleiseen hätänumeroon soitetut puhelut. Erityisesti laite- ja verkkotoimittajat odottivat tämänluovan heille uusia markkinoita. Markkinoille tuli useita kilpailevia menetelmiä, joilla matkapuhelimia voitiin paikantaa. Suurin osa näistä menetelmistä hyödynsi GSM-verkon signalointia paikannuksen tekemiseen. Samaan aikaan kohonnut matkapuhelinten suorituskyky mahdollisti GPS-vastaanottimien integroinnin matkapuhelimiin ja ensimmäiset tällaiset matkapuhelimet ilmestyivät markkinoille. Matkapuhelinten paikantamiseen liittyvä standardointi on melko hajanaista. ETSI on standardoinut joukon erilaisia menetelmiä, joilla matkapuhelin paikkatieto voidaan selvittää. Nämä standardit eivät kuitenkaan määrittele sitä, kuinka paikkatieto siirretään sitä hyödyntävien palveluiden käyttöön. Paikkatiedonsiirtämiseen ja esittämiseen liittyvässä standardoinnissa eri laite- ja ohjelmistovalmistajat ovat tehneet liittoutumia keskenään ja esitelleet keskenään kilpailevia standardeja ja suosituksia. Tälläkään osa-alueella mikään liittoutuma ei ole saavuttanut määräävää markkina-asemaa. Tässä työssä suunniteltiin ja toteutettiin järjestelmä, jonka avulla voidaan paikantaa sellaisia GSM-päätelaitteita, joihin on integroitu GPS-vastaanotin. Toteutettu järjestelmä liitettiin uudeksi paikannusmenetelmäksi solupaikannuksen rinnalle Sonera Pointer paikannusjärjestelmään. Työn aikana testattiin joukko markkinoilla olleita GSM-puhelimia, joihin oli integroitu GPS-vastaanotin. Matkapuhelinten testauksessa erityinen huomio kiinnittyi siihen, kuinka GPS-paikkatieto saadaan siirrettyä matkapuhelimesta verkossa sijaitsevien sovellusten käyttöön. Toteutetun järjestelmän suunnittelussa täkein lähtökohta oli järjestelmän joustavuus. Standardien hajanaisuus ja osittainen puuttuminen aiheuttivat sen, että järjestelmästä oli tehtävä mahdollisimman helposti laajennettava. Toinen merkittävä suunnitteluun vaikuttanut tekijä oli operaattoririippumattomuus, koska Sonera Pointer järjestelmää oli tarkoitus myydä myös muille matkapuhelinoperaattoreille.

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A new design of' a dual-frequency dual-polarized square microsh'ip antenna fed along the diagonal, embedded with a square slot having three extended stubs for frequency tuning, is introduced. The proposed antenna was fabricated using a standard photolithographic method and the antenna was tested using the HP 3510(:; Vector Network Analyser. The antenna is capable of generating dual resonant frequencies with mutually perpendicular polarizations and broad radiation pattern characteristics. Such dual-frequency designs find wide applications in personal mobile handsets combining GSM and CDS 1800 modes, and applications in which different frequencies are used for emission and reception such as personal satellite communications and cellular network systems.

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Media content distribution on-demand becomes more complex when performed on a mass scale involving various channels with distinct and dynamic network characteristics, and, deploying a variety of terminal devices offering a wide range of capabilities. It is practically impossible to create and prepackage various static versions of the same content to match all the varying demand parameters of clients for various contexts. In this paper we present a profiling management approach for dynamically personalised media content delivery on-demand integrated with the AXMEDIS Framework. The client profiles comprise the representation of User, Device, Network and Context of content delivery based on MPEG-21:DIA. Although the most challenging proving ground for this personalised content delivery has been the mobile testbed i.e. the distribution to mobile handsets, the framework described here can be deployed for disribution, by the AXMEDIS PnP module, through other channels e.g. satellite, Internet to a range of client terminals e.g. desktops, kiosks, IPtv and other terrminals whose baseline terminal capabilities can be made availabe by the manufacturers as is normal.

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Este Proyecto Fin de Carrera (PFC) tiene como objetivo el análisis, diseño e implementación de un videojuego móvil multijugador, con un enfoque educativo, para la sensibilización sobre el Índice de Desarrollo Humano (IDH). El sistema resultante se ha desarrollado para la Plataforma Android, utilizando el Framework AndEngine, que utiliza aceleración hardware de la GPU para garantizar un buen rendimiento en terminales de gama baja, de modo que pueda utilizarse en un amplio número de terminales móviles disponibles en el mercado. La aplicación se presenta como un juego de cartas con los diferentes países y sus datos humanitarios, los jugadores deben conocer el peso de los índices de desarrollo (esperanza de vida, renta, educación) de los países en comparación con los países de los otros jugadores. El sistema de juego premia a los jugadores con mayores conocimientos sobre los datos humanos de los diferentes países del mundo, de ese modo los mejores jugadores serán los que tengan más conocimientos de estos datos. El juego permite jugar partidas en solitario utilizando jugadores manejados por la CPU, o multijugador mediante WIFI o 3G. La actualización de la información y de los datos de las partidas se realiza a través de la comunicación con un servidor web ya implementado de forma complementaria a la realización de este proyecto. El sistema ha sido integrado y validado satisfactoriamente con diferentes terminales móviles y usuarios de diferente perfil de edad y uso. El videojuego se puede descargar de la página web creada en un proyecto complementario a éste (pendiente de publicación web), y ya se encuentra también disponible en Google Play. https://play.google.com/store/apps/details?id=xnetcom.pro.cartas&hl=es_419 ABSTRACT. This Project End of Career (PFC) takes as an aim the analysis, design and implementation of a multiplayer mobile videogame, with an educational approach, for the awareness on the Human Development Index (HDI). The resultant system has been developed for the Platform Android, using the AndEngine Framework, which uses hardware acceleration of the GPU to ensure a good performance on low-end terminals, so that it can be used in a wide range of mobile handsets available in the market. The application is presented as a card game with the different countries and his humanitarian information, the players must know the weight of the indexes of development (life expectancy, revenue, education) of the countries in comparison with the countries of other players. The game system rewards players with more knowledge on human information of different countries, thus the best players will be those with more knowledge of these information. The game allows to play items in solitarily using players handled by the CPU, or multiplayer by means of WIFI or 3G. The update of the information and data of the online games is done through communication with a web server implemented as a complement to the realization of this project. The system has been built and successfully validated with different mobile terminals and users of different age and usage profile. The game can be downloaded from the website created in a complementary project to this (web publication pending), and is now also available on Google Play https://play.google.com/store/apps/details?id=xnetcom.pro.cartas&hl=es_419

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From the Introduction. The Media Sector has experienced a technological revolution in the last 15 years. Digital encoding of television signals made possible a more efficient use of the radiospectrum. Digital terrestrial television (hereinafter, “DTT”) allows now for the reception of a significant number of free-to-air channels.1 Moreover, the use of new transmission platforms (hereinafter,“platforms”), namely cable and direct-to-home satellite (hereinafter, “DTH”) paved the way for the arrival in Europe of pay-TV operators, which finance their activities mainly via subscription fees. This changing technological landscape is subject to further evolution in the near future, as incumbent telecommunications operators become increasingly interested in making available broadcasting content2 as part of their broadband offer and 3G mobile handsets can be used for the reception of TV signals....The present paper seeks to ascertain whether the Commission “regulatory approach” towards the exclusive sale of premium content is a sound one, in particular in view of the constant technological evolution outlined above. The assumptions underlying landmark Commission decisions will be compared with recent developments of the media sector in Italy. In the NewsCorp./Telepiù case, decided in 2003, the Commission imposed very strict conditions to allow the merger giving birth to Sky Italia, on the assumption that the operation created a lasting near-monopsony in the different upstream markets for the acquisition of premium intervened against the media conglomerate Mediaset (which controls, inter alia, the main three private free-to-air channels in Italy) for an alleged abuse of dominant position.17 In fact, and contrary to the forecasts made by the Commission, Mediaset was in a position to acquire the broadcasting rights of the main Italian football teams, thereby excluding the incumbent (and near-monopolist) pay-TV operator, Sky Italia. This may go to show that the reality of the sector is more complex and evolves faster than one may infer from the Commission practice, thus putting into question its stance regarding exclusivity. The experience of the evolution of the Italian media sector will be used as the starting point for the evaluation of alternative regulatory options.

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Starting from almost null in the late 1990s, China's mobile phone handset industry has grown to account for more than 40 percent of the current world production. While export growth has been overwhelmingly led by multi-national corporations (MNCs), increasingly fierce competition in the domestic market ignited by the advent of local handset makers has induced unique industrial evolution: (1) outgrowth of independent design houses specialized in handset development and (2) emergence of IC fabless ventures that design core ICs for handsets. In the background of this evolutionary industrial growth there are factors such as, the scale and increasing diversity of China's domestic market that advantages local firms vis-a-vis MNCs; modularization of handset and semiconductor technologies; policy interventions that supports local startups. The emergence and evolution of China's handset industry is likely to have international implications as the growth of the global demand for low-cost and multi-function mobile phone handsets is expected to accelerate. Thus, our case suggests that the conventional view of latecomer industrialization and upgrading that emphasizes the key role of international production networks organized by MNCs needs to be modified in order to accommodate China's rise into perspective.

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The present work has aimed to determine the 16 US EPA priority PAH atmospheric particulate matter levels present in three sites around Salvador, Bahia: (i) Lapa bus station, strongly impacted by heavy-duty diesel vehicles; (ii) Aratu harbor, impacted by an intense movement of goods, and (iii) Bananeira village on Maré Island, a non vehicle-influenced site with activities such as handcraft work and fisheries. Results indicated that BbF (0.130-6.85 ng m-3) is the PAH with highest concentration in samples from Aratu harbor and Bananeira and CRY (0.075-6.85 ng m-3) presented higher concentrations at Lapa station. PAH sources from studied sites were mainly of anthropogenic origin such as gasoline-fueled light-duty vehicles and diesel-fueled heavy-duty vehicles, discharges in the port, diesel burning from ships, dust ressuspension, indoor soot from cooking, and coal and wood combustion for energy production.

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In this paper, nonlinear dynamic equations of a wheeled mobile robot are described in the state-space form where the parameters are part of the state (angular velocities of the wheels). This representation, known as quasi-linear parameter varying, is useful for control designs based on nonlinear H(infinity) approaches. Two nonlinear H(infinity) controllers that guarantee induced L(2)-norm, between input (disturbances) and output signals, bounded by an attenuation level gamma, are used to control a wheeled mobile robot. These controllers are solved via linear matrix inequalities and algebraic Riccati equation. Experimental results are presented, with a comparative study among these robust control strategies and the standard computed torque, plus proportional-derivative, controller.

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Many Archean cratons are surrounded by Proterozoic mobile belts that have experienced episodes of tectonic re-activation over their lifetimes. This suggests that mobile belt lithosphere may be associated with long lived, inherited weakness. It is proposed that the proximity of this weakness can increase the longevity of deep Archean lithosphere by buffering Archean cratons from mantle derived stresses. The physical plausibility of this idea is explored through numerical simulations of mantle convection that include continents and allow for material rheologies that model the combined brittle and ductile behavior of the lithosphere. Within the simulations, the longevity of deep cratonic lithosphere does increase if it is buffered by mobile belts that can fail at relatively low stress levels.