Low Profile Multi-Band Antenna for Mobile Communications

In this paper, the design of low profile antennas by using Electromagnetic Band Gap (EBG) structures is introduced. Taking advantage of the fact that they can behave as Perfect Magnetic Conductor (PMC), it is shown that these structures exhibit dual band in-phase reflection at WLAN (Wireless Local Area Network) bands, the 2.4 GHz and 5.2 GHz bands. These structures are applied to PIFA (Planar Inverted-F Antenna) and the results show that it is possible to obtain low profile PIFA's.

Exploring the use of mobile communications in a retirement home in Toronto: Preliminary results

This paper describes preliminary results of a qualitative case study on mobile communication conducted in an elders¿ retirement home in Toronto (Ontario, Canada) in May 2012. This is part of an international research project on the relationship between mobile communications and older people.Secondary data at a Canadian level contextualizes the case study. We focus ondemographic characteristics and on adoption and use of information and communication technologies (ICTs) broken by age.Participants in the study (21 individuals) are between 75 and 98 years of age, thereforewe can consider that the gathered evidence refers to the ¿old¿ older. Mobile phoneusers in the sample describe very specific uses of the mobile phone, while non-usersreport not facing external pressures for adopting that technology. The main channel formediated communication is the landline; in consequences mobile phones ¿when used¿ constitute an extra layer of communication. Finally, when members of the personal network of the individuals live abroad they are more prone to use Internet and Skype. We are also able to find ex-users of both mobile telephony and computers/internet who stopped using these technologies because they did not find any use for them.

Exploring the use of mobile communications in a sample of older people: Preliminary results of a case study in Los Angeles

This paper introduces a qualitative case study on mobile communication among the older population (60+ years old) conducted in Great Los Angeles (CA, USA) in autumn 2011. Methodology, fieldwork and preliminary results are discussed.Before, country-level data is presented to better understand the specific characteristics of the studied individuals. The section focus is on demographics and on acceptance and use of information and communication technologies (ICT).Preliminary results show that within the sample under study (20 individuals) there is a high number of mobile phone users (15) while among non-mobile users (5), three of them decide to stop using this technology. A majority of mobile phone adopters describe a very limited use of the device for everyday life communications. Finally,while Internet is really popular within the sample (14 users), just 3 individuals go online through their mobile telephone.

Robust beamforming for interference rejection in mobile communications

The problem of robust beamformer design for mobile communicationsapplications in the presence of moving co-channel sources isaddressed. A generalization of the optimum beamformer based on a statisticalmodel accounting for source movement is proposed. The new methodis easily implemented and is shown to offer dramatic improvements overconventional optimum beamforming for moving sources under a varietyof operating conditions.

Wireless Application Test Bed and Simulations for Broadband Mobile Communications Systems

Langattoman laajakaistaisen tietoliikennetekniikan kehittyminen on herättänyt kiinnostuksen sen ammattimaiseen hyödyntämiseen yleisen turvallisuuden ja kriisinhallinnan tarpeisiin. Hätätilanteissa usein olemassa olevat kiinteät tietoliikennejärjestelmät eivät ole ollenkaan käytettävissä tai niiden tarjoama kapasiteetti ei ole riittävä. Tästä syystä on noussut esiin tarve nopeasti toimintakuntoon saatettaville ja itsenäisille langattomille laajakaistaisille järjestelmille. Tässä diplomityössä on tarkoitus tutkia langattomia ad hoc monihyppy -verkkoja yleisen turvallisuuden tarpeiden pohjalta ja toteuttaa testialusta, jolla voidaan demonstroida sekä tutkia tällaisen järjestelmän toimintaa käytännössä. Työssä tutkitaan pisteestä pisteeseen sekä erityisesti pisteestä moneen pisteeseen suoritettavaa tietoliikennettä. Mittausten kohteena on testialustan tiedonsiirtonopeus, lähetysteho ja vastaanottimen herkkyys. Näitä tuloksia käytetään simulaattorin parametreina, jotta simulaattorin tulokset olisivat mahdollisimman aidot ja yhdenmukaiset testialustan kanssa. Sen jälkeen valitaan valikoima yleisen turvallisuuden vaatimusten mukaisia ohjelmia ja sovellusmalleja, joiden suorituskyky mitataan erilaisten reititysmenetelmien alaisena sekä testialustalla että simulaattorilla. Tuloksia arvioidaan ja vertaillaan. Multicast monihyppy -video päätettiin sovelluksista valita tutkimusten pääkohteeksi ja sitä sekä sen ominaisuuksia on tarkoitus myös oikeissa kenttäkokeissa.

Mobile Communications within the European Union: The Role of Location in the Evolution and Forecasting of the Diffusion Process

In the European Union, the importance of mobile communications was realized early on. The process of mobile communications becoming ubiquitous has taken time, as the innovation of mobile communications diffused into the society. The aim of this study is to find out how the evolution and spatial patterns of the diffusion of mobile communications within the European Union could be taken into account in forecasting the diffusion process. There is relatively lot of research of innovation diffusion on the individual (micro) andthe country (macro) level, if compared to the territorial level. Territorial orspatial diffusion refers either to the intra-country or inter-country diffusionof an innovation. In both settings, the dif- fusion of a technological innovation has gained scarce attention. This study adds knowledge of the diffusion between countries, focusing especially on the role of location in this process. The main findings of the study are the following: The penetration rates of the European Union member countries have become more even in the period of observation, from the year 1981 to 2000. The common digital GSM system seems to have hastened this process. As to the role of location in the diffusion process, neighboring countries have had similar diffusion processes. They can be grouped into three, the Nordic countries, the central and southern European countries, and the remote southern European countries. The neighborhood effect is also domi- nating in thegravity model which is used for modeling the adoption timing of the countries. The subsequent diffusion within a country, measured by the logistic model in Finland, is af- fected positively by its economic situation, and it seems to level off at some 92 %. Considering the launch of future mobile communications systemsusing a common standard should implicate an equal development between the countries. The launching time should be carefully selected as the diffusion is probably delayed in economic downturns. The location of a country, measured by distance, can be used in forecasting the adoption and diffusion. Fi- nally, the result of penetration rates becoming more even implies that in a relatively homoge- nous set of countries, such as the European Union member countries, the estimated final pene- tration of a single country can be used for approximating the penetration of the others. The estimated eventual penetration of Finland, some 92 %, should thus also be the eventual level for all the European Union countries and for the European Union as a whole.

Effect of competitive situation and price on diffusion of mobile communications

Työn päätavoitteena oli selvittää hinnan ja kilpailutilanteen vaikutusta matkaviestinnän diffuusioon. Työn empiirinen osuus tarkasteli matkapuhelinliittymien hinnan vaikutusta liittymien diffuusioon sekä sitä, miten alan kilpailu on vaikuttanut matkaviestinnän hintatasoon. Työssä analysoitiin myös matkaviestinnän kilpailutilannetta Suomen markkinoilla. Tutkimuksen empiirinen aineisto kerättiin toissijaisista lähteistä, esimerkiksi EMC-tietokannasta. Tutkimus oli luonteeltaan kvantitatiivinen.Empiirisessä osassa käytetyt mallit oli muodostettu aikaisempien tutkimuksien perusteella. Regressioanalyysiä käytettiin arvioitaessa hinnan vaikutusta diffuusionopeuteen ja mahdollisten omaksujien määrään. Regressioanalyysissä sovellettiin ei-lineaarista mallia.Tutkimustulokset osoittivat, että tasaisesti laskevilla matkapuhelinliittymien sekä matkapuhelimien hinnoilla ei ole merkittävää vaikutusta matkaviestinnän diffuusioon. Myöskään kilpailutilanne ei ole vaikuttanut paljon matkaviestinnän yleiseen hintatasoon. Työn tulosten perusteella voitiin antaa myös muutamia toimenpide-ehdotuksia jatkotutkimuksia varten.

A new microstrip patch antenna for mobile communications and bluetooth applications

compact multihand planar octagonal-shaped microstrip antenna simultaneously suitable for mobile communication and blue tooth application is presented. The antenna provides sufficient isolation benveen the two operating bands and an area reduction of -29 % with respect to a circular patch operating in the same band

MIMO Wiener model identification for large scale fading of wireless mobile communications links

The large scale fading of wireless mobile communications links is modelled assuming the mobile receiver motion is described by a dynamic linear system in state-space. The geometric relations involved in the attenuation and multi-path propagation of the electric field are described by a static non-linear mapping. A Wiener system subspace identification algorithm in conjunction with polynomial regression is used to identify a model from time-domain estimates of the field intensity assuming a multitude of emitters and an antenna array at the receiver end.

Design and implementation of wireless sensor networks for impedance-based structural health monitoring using ZigBee and Global System for Mobile Communications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

5g mobile communications systems

Un sistema mobile di comunicazione è un sistema di telecomunicazioni in cui è possibile mantenere la connessione o legame tra due o più utenti, anche nelle situazioni di mobilità totale o parziale degli stessi utenti. I sistemi radiomobili si stanno evolvendo dalla creazione del 1G (prima generazione) al 4G (quarta generazione). I telefoni di ogni generazione si differenziano in quattro aspetti principali : accesso radio, velocità di trasmissione dati, larghezza di banda e sistemi di commutazione. In questa tesi si affronta il tema dei sistemi 5G , negli ambienti terrestri e satellitari , in quanto sono l'ultima evoluzione dei sistemi mobili . Si introduce il passaggio dalla prima alla connessione di quarta generazione , al fine di capire perché 5G sta per cambiare la nostra vita . Quello che mi colpisce è il sito italiano www.Repubblica.it che dice : " con la nuova generazione 5 possiamo affidare le intere porzioni nette di vita". La tecnologia cellulare , infatti , ha cambiato radicalmente la nostra società e il nostro modo di comunicare . In primo luogo è cambiata la telefonia vocale , per poi trasferirsi all' accesso dati , applicazioni e servizi. Tuttavia , Internet non è stato ancora pienamente sfruttato dai sistemi cellulari. Con l'avvento del 5G avremo l'opportunità di scavalcare le capacità attuali di Internet . Il sistema di comunicazione di quinta generazione è visto come la rete wireless reale , in grado di supportare applicazioni web wireless a livello mondiale ( wwww ). Ci sono due punti di vista dei sistemi 5G : evolutivo e rivoluzionario. Dal punto di vista evolutivo, i sistemi 5G saranno in grado di supportare wwww permettendo una rete altamente flessibile come un Adhoc rete wireless dinamica ( DAWN ) . In questa visione tecnologie avanzate, tra cui antenna intelligente e modulazione flessibile , sono le chiavi per ottimizzare le reti wireless ad hoc. Dal punto di vista rivoluzionario, i sistemi 5G dovrebbe essere una tecnologia intelligente in grado di interconnettere tutto il mondo senza limiti . Un esempio di applicazione potrebbe essere un robot wireless con intelligenza artificiale .

New Freedom through Medical Devices Based on the Global System for Mobile Communications: A Prospective Survey of 620 Users of the Swiss Limmex Emergency Wristwatch-An Original Study from Switzerland

About 500,000 elderly people in Switzerland suffer a fall each year. Thus medical attention and help are essential for these people, who mostly live alone without a caregiver. Only 3% of people aged over 65 in Switzerland use an emergency system. Personal telehealth devices allow patients to receive enough information about the appropriate treatment, as well as followup with their doctors and reports of any emergency, in the absence of any caregiver. This increases their quality of life in a cost-effective fashion. "Limmex"-a new medical emergency watch-was launched in Switzerland in 2011 and has been a great commercial success. In this paper, we give a brief review of this watch technology, along with the results of a survey of 620 users conducted by the Department of Emergency Medicine in Bern.