Plenary Lecture

The Application of GIS in Wireless Communication Systems with Diversity Combining in the Presence of Fading

Professor Dragana Krstić
Faculty of Electronic Engineering
University of Niš

Abstract: The application of Geographic Information Systems (GIS) in designing of wireless communication systems with diversity combining in the presence of fading is very important. In wireless telecommunication systems various problems that reduce the range of connections, corrupt receipt of the antenna and increase the transmitter power needed, appear in wireless telecommunication systems. The troubles, which occur in wireless telecommunication systems, are different noise, interferences and fading. The diversity techniques for reducing the impact of disturbances on system performances are considered. There are space diversity, time diversity and frequency diversity systems. Here, the space diversity techniques will be discussed.
Fundamental obstacle in wireless telecommunication systems is fading. Fading is the signal envelope changing at the receiving site and it may be fast and slow fading. Fast fading is caused by multiple signal propagation paths. Slow fading is caused by the effect of shadows. Fast fading can be modeled by Ricean, Rayleigh, Nakagami-m, Nakagami-q, and Weibull probability density functions. In some cases, fast fading can be modeled with an inverse Gaussian probability density function. Slow fading can be modeled with log-normal and Gamma probability density functions. Also, slow fading can be modeled with Rician and Nakagami-m probability density function in some cases.
A large number of applications of geographic information systems is related to the telecommunications sector. Due to prediction the propagation and visualization of the signal range, these systems are widely used in various kinds of electromagnetic waves simulation in a particular environment where wireless telecommunications systems are projected. Of crucial importance for the design of these systems is the propagation of signals in space. These systems are used in designing of wireless and mobile telecommunication systems, radar networks, and radio-relay links. In all these cases the savings in time, human resources and material resources are achieved, because much of the design of the networks is the computer's work, without going out into the field.

Brief Biography of the Speaker:Dragana S. Krstic was born in Pirot, Serbia. She received the BSc, MSc and PhD degrees in electrical engineering from Department of Telecommunications, Faculty of Electronic Engineering, University of Nis, Serbia, in 1990, 1998 and 2006, respectively. Her field of interest includes telecommunications theory, optical communication systems, wireless communication systems, satellite communication systems etc. She works at the Faculty of Electronic Engineering in Nis since 1990. She participated in more Projects which are supported by Serbian Ministry of Science. She has written or co-authored more about 160 papers, published in Journals and at the International/National Conferences. She has also reviewed more articles in IEEE Transactions on Communications; IEEE Communications Letters; ETRI journal; C&EE Journal; Electronics and Electrical Engineering (Elektronika ir Elektrotechnika) and other journals. She is the reviewer of the papers for many conferences and the member of technical program committees and international scientific committees of several scientific conferences. Also, she is the member of Editorial Board of International Journal On Advances in Telecommunications.