The General Packet Radio Service (GPRS) is the first evolutionary step, in deploying a truly mobile wireless internet capability, for GSM and TDMA operators. As an upgrade to currently deployed networks, operators providing GPRS must be able to provide this service, with acceptable quality, within the physical constraints of the existing system infrastructure. As a result, it is imperative that the operator’s technical and marketing personnel be cognizant of the difference in performance characteristics, at the physical layer, between GPRS and GSM or TDMA. This chapter identifies the physical layer characteristics, and expected system performance, for slow moving and stationary terminal units.

General Packet Radio Service (GPRS)

L'avancement de la communication numerique optique dans les reseaux longue distance et d'acces a declenche les technologies emergentes dans le domaine micro-ondes / ondes millimetriques. Ces systemes hybrides sont fortement influences non seulement par les deficiences de liens optiques mais aussi des effets de circuits electriques. Les effets optiques et electriques peuvent etre ainsi etudies en meme temps en utilisant des outils assistes par ordinateur en developpant des modeles de circuit equivalent de l'ensemble des composants de liaison tels que les lasers a semi-conducteurs, modulateurs, photo-detecteurs et fibre optique. Dans cette these, les representations de circuit des composants de liaison photoniques sont developpees pour etudier des architectures differentes. Depuis la source de lumiere optique est le principal facteur limitant de la liaison optique, une attention particuliere est accordee aux caracteristiques, y compris les plus importants de simples lasers en mode semi-conducteurs. Le modele de circuit equivalent de laser qui represente l'enveloppe du signal optique est modifie pour inclure les proprietes de bruit de phase du laser. Cette modification est particulierement necessaire d'etudier les systemes ou le bruit de phase optique est important. Ces systemes comprennent des systemes de telecommande heterodynes optiques et des systemes auto-heterodynes optiques. Les resultats de mesure des caracteristiques de laser sont compares aux resultats de simulation afin de valider le modele de circuit equivalent dans des conditions differentes. Il est demontre que le modele de circuit equivalent peut predire avec precision les comportements des composants pour les simulations au niveau du systeme. Pour demontrer la capacite du modele de circuit equivalent de la liaison photonique pour analyser les systemes micro-ondes / ondes millimetriques, le nouveau modele de circuit du laser avec les modeles comportementaux des autres composants sont utilises pour caracteriser differents radio sur fibre (RoF) liens tels que la modulation d'intensite - detection directe (IM-DD) et les systemes RoF heterodynes optique. Signal sans fil avec des specifications conformes a la norme de IEEE 802.15.3c pour la bande de frequence a ondes millimetriques est transmis sur les liens RoF. La performance du systeme est analysee sur la base de l'evaluation de l'EVM. L'analyse montre que l'analyse efficace des systemes de photonique micro-ondes / ondes millimetriques est obtenue en utilisant des modeles de circuit qui nous permet de prendre en compte les comportements a la fois electriques et optiques en meme temps

https://tel.archives-ouvertes.fr/tel-01272374/document

Modélisation électrique de laser semi-conducteurs pour les communications à haut débit de données.

Potentials and Limits of Cooperation in Wireless Communications: Towards 4G Wireless

Pursuit for a new feasible technology has always been the main intention of every telecom company. Keeping in line with current trends, user preferences and requirements, technology standards have evolved from 1G, 2G, 3G, 4G and now 5G. The new standards proved an opportunity for the technology community to address certain limitations that has been observed in the 4G network. Critical issues like enhancement of battery power, bandwidth restrictions, and latency, among other things, have been drastically improved. Thus, this chapter intends to discuss the various performance parameters, necessities, evolutionary enhancements, and the challenges to deploy 5G Mobile network.

Different Aspects of 5G Wireless Network: An Overview

The major ideology behind this paper is to find out and clarify the till date development of GSM in SAARC countries. Asia, being the largest continent in the world, however has not been able to penetrate to the widest depth into the sea of telecommunications. Moreover, some of the SAARC countries are at the lowest level in the scale. Keeping this into consideration, this paper just tries to bring out the miniature reasons for some of these countries to lag along with the so far development in GSM technology that has taken place in these 8 SAARC countries. This paper covers the up to date information about the GSM technology since the day of its birth in the SAARC countries which are: Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. Moreover, this paper has also tried to address the so far challenges being faced in the sector of GSM technology development in these countries along with the prominent steps that were wisely taken to eliminate them. Ultimately, this paper covers the so far development till 4G networking in the SAARC countries in various sectors such as military and medicine.

Performance and Improvement of GSM and 4G Networking in Development Countries

In this paper, we discuss the evolution of the mobile communication systems from GSM to LTE (2G to 4G) and the trends in the mobile communication industry. The Global System for Mobile Communication (GSM) is a well established cellular system targeted here due to its engineering success and the large number of users currently using the services. The flexibility of wireless networks over voice and data transmission makes it one of the most popular modes of communication. Evolution to next generation services depends on an addition of new services and new features to the existing networks or even an integration of different communication technologies. With the invention of the devices such as tablets and smart phones the need to improve the data transmission rates and transmission efficiency has increased to higher than ever before. In this paper, we focus at some of the important issues pertaining to the evolution of mobile communication networks and predict the future of the networks based on the analysis of the cellular market in India. Since GSM networks accounts for more than 75% of the world wide cellular network, only the evolution of GSM network has been discussed in this paper.

/pdf/evolution-of-wireless-mobile-communication-networks-and-2o0v5vccos.pdf

Evolution of wireless mobile communication networks and future of cellular market in india

A 8x8 multiple input multiple output antenna is developed for the applications of MM wave. this proposed model has 8 ports on the single structure of antenna system. The proposed design gives a triple bands k-band (14.6 at-22dB), ku-band (19.6 at -28dB) and ka-band (27.6 at -27dB) which this ka-band wii be act as mm wave band for the applications of MM wave. The proposed antenna having the dimensions of 64mm x 32mm x 1.6 mm having thickness 1.6mm and the Fr4 substrate has been used for designing. The proposed antenna is designed, measured and tested

/pdf/mutual-coupling-reduction-using-8x8-mimo-antenna-for-mm-wave-1wgbdtkj.pdf

Mayur Rao

Papers

Evolution of wireless mobile communication networks and future of cellular market in india

Mutual Coupling Reduction Using 8x8 MIMO Antenna for MM Wave Applications