Login

 


Plenary Lecture

The Mitigation of Fading and Shadowing Influences in Wireless Telecommunications

Professor Dragana Krstić
Faculty of Electronic Engineering
University of Niš
Serbia
E-mail: dragana.krstic@elfak.ni.ac.rs

Abstract: The wireless channels are simultaneously affected by short-term fading (fast fading) and long-term fading (shadowing). Fast fading is caused by multiple signal propagation paths. Due to the shadowing from various objects in the propagation paths, in addition to multipath fading, the quality of the received signal is also affected by slow variations of the mean signal level In wireless communication systems, various techniques for reducing fading effect and influence of shadow effect are used: diversity reception, dynamic channel allocation and power control. Upgrading transmission reliability and increasing channel capacity without increasing transmission power and bandwidth is the main goal of diversity techniques. Well-known means to mitigate the effects of fading and shadowing is diversity reception. It exploits the random nature of the radio propagation by combining, or selecting from two or more independent (or at least highly uncorrelated) fading signal paths, resulting in improved system performance. The wireless communication system following microdiversity to mitigate the effects of fast fading and macrodiversity processing to reduce shadowing effects are studed. Fast signal variations are described by several distributions such as Rayleigh, Rice, Nakagami-m, α-μ, Weibull and Hoyt. Diversity reception, based on using multiple antennas at the receiver (space diversity, with two or more branches) is a very efficient method used for improving system’s quality of service. Multiple received copies of signal could be combined on various ways. Usually L-branch maximal-ratio combining (MRC) or selection combining (SC) is implemented at the micro level (single base station) and selection combining (SC) with two base stations (dual diversity) is implemented at the macro level. Complex mathematical calculations are used to obtain telecommunication system performances.

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.

Bulletin Board

Currently:

The conference program is online.

The Conference Guide is online.

The paper submission deadline has expired. Please choose a future conference to submit your paper.


WSEAS Main Site


NAUN Main Site

Publication Ethics and Malpractice Statement