Preface GSM Basics

Mobile communication systems, especially cellular mobile communication systems, along with space, television and computer systems, are among the most important achievements of mankind in the 20th century in the field of information systems and technologies.

Cellular mobile communication, which appeared at the idea level in BellSystem projects in the late 40s and by 1978 implemented as the first experimental network (Chicago, 2000 subscribers), by 2004 had avalanche gained one of the key positions in the field of information technology: for 2004 over the year, over 1.5 billion users were covered by cellular mobile communications worldwide.

Such a rapid development of cellular mobile communication systems can be explained by the following reasons.
1. Development of microelectronics allowed creating small-sized, universal, relatively cheap devices providing high quality, reliability and security of transmitted information.
2. The needs of the general population in the use of a wide range of services:
- high-quality voice and computer data transmission between subscribers moving in space, including with access to landline telephone networks;
- search for mobile subscribers and establishing communication with them within the city, country and worldwide;
- ability to connect to ISDN, PSTN, Internet;
- identification of subscriber authenticity;
- automatic registration of communication session and charging, etc.

According to generalized forecasts for the next 10-15 years, the provision of the population of the planet with mobile telephone communication in industrialized countries can reach from 50 to 80%. This means that a mobile phone will become no less common than a regular landline wired telephone.
With a fairly rapidly expanding market for cellular mobile network services in the world, the bibliographic market in Eastern

Europe is relatively poor. Until now, there is practically no simple and accessible book for a wide range of readers interested in cellular mobile communications, especially in the GSM standard, which is widely used in Europe.
At the same time, dozens of books appear annually in Western Europe, the USA, and Japan, as well as hundreds of articles and patents in the field of mobile communication systems.

This book, written on the basis of lecture notes, which the author reads at the Riga Technical University in the disciplines "Mobile communication systems in railway transport", "Designing cellular communication systems", to some extent should solve the above problem.

The author intentionally limited the scope of the book to consideration of the cellular mobile communication system of the GSM standard for the following reasons:
- first, GSM networks are one of the most widely used in Europe (Pan European Cellular System) and in the world of cellular mobile communication system standards (GSM 900/1800/1900);
- secondly, GSM is a functionally developing cellular mobile communication system, while in the future the main functional elements of GSM will be included in the 3rd generation cellular international mobile communication system - IMT-2000 (International Mobile Telecommunication '2000) UMTS (Universal Mobile). Telecommunication System- universal mobile telecommunication system);
- thirdly, the GSM standard is widely implemented in Europe in the systems of automated control and transmission of information on high-speed railways, the so-called GSM-Railway standard.

The first chapter of the book is devoted to a brief history of the development of mobile communication systems of the GSM standard, features of the GSM standard, its general and technical characteristics.

In the second chapter, the principles of cellular mobile communication network organization, GSM network structure, interfaces and protocols, multiple access methods (FDMA, TDMA), GSM communication channels are considered.

The third chapter deals with the emission of electromagnetic waves, antennas and their parameters, mobile station antennas, features of radio wave propagation in cellular mobile communication systems, propagation characteristics, radio channel models under multipath propagation of radio waves, provides calculations of the electromagnetic field emitted by base receiving-transmitting antennas within a cell, the levels of the received radio signal in urban environments, the characteristics of radio wave propagation in forests and .

The fourth chapter is devoted to mobile stations of the GSM standard, methods of converting speech signals to digital, methods of coding / decoding, modulation / demodulation, controlling the power of transmitters and other technical features of the functioning of mobile stations.

In the fifth chapter , the characteristics of base stations and their antenna systems are described quite concisely.

The sixth chapter is devoted to the problems of establishing communication, authentication, identification, transfer service, roaming and other problems associated with the functioning of the cellular network of the GSM standard.

The seventh chapter deals with the problems of designing and monitoring cellular mobile communication systems.

The eighth chapter deals with services, fraud and security in cellular mobile communication systems.

The ninth chapter is devoted to the management of communication networks in the GSM standard (tasks of the network management system, principles of building a network management system, distribution of network management functions in the GSM standard, standard interfaces in the network management system).

The tenth chapter examines the prospects for the development of cellular mobile communication systems, including the systems of the 3rd generation and the 21st century.

The author sought to find a compromise between the sufficient completeness of the content and the impossibility of excessive detailing while maintaining the availability of the presentation, therefore, in the presented form, the book cannot fail to have shortcomings in the completeness of the coverage, the presentation method and the actual content.

The author would be grateful for any critical comments, constructive feedback, containing specific suggestions and suggestions.

POPOV Valentin Ivanovich

Professor, Doctor of Physical and Mathematical Sciences, member of the Optical Society of America, head of the faculty group "Communication Systems and Information Systems in Transport" of the Institute of Railway Transport at Riga Technical University.

Specialist in the fields of radiophysics, communication systems and information systems in transport, fiber-optic and mobile communication systems.

Ator more than 150 scientific papers, including several books.

In recent years, the main scientific interests are: the design of fiber-optic communication systems and cellular mobile communication systems in transport, the propagation of radio waves in forests, the effect on the human body of electromagnetic radiation.

Hobby - a professional singer (tenor).

In a systematic way, the basics of GSM mobile cellular communication systems are considered. It contains information about the history of GSM development, the general characteristics of the GSM standard, the principles of TDMA, coding, modulation, problems of calculating the electromagnetic field at reception points with regard to multipath propagation. The structure and components of cellular communication systems, problems of designing, monitoring and managing networks, and a number of other technical problems are considered. A set of basic services is described, fraud problems in cellular mobile communication systems are considered. Prospects for the development of GSM standard systems and the evolution of GSM networks to the third generation of 21st century mobile communications are assessed.

There are a large number of examples.

The book is intended for a wide range of readers interested in the problems of cellular mobile communication. It will be useful for university students specializing in telecommunications and communications, as well as professionals involved in the design and development of cellular systems.