20 research outputs found
Capacity Analysis of the Fluctuating Double-Rayleigh with Line-of-Sight Fading Channel
The proposed research performs the capacity analysis of the wireless channel
described by the fluctuating double-Rayleigh with the line-of-sight model. The
closed-form analytical expressions for the conditional capacity (in the case of
arbitrary noninteger fading parameter) and the ergodic capacity (in the case of
the integer fading parameter) are derived in terms of the extended generalized
bivariate Meijer G-function. The exact solutions are succeeded by the
approximating expressions deduced for the cases of small and large ratios
between the Rician K-factor and the fading parameter. The performed numeric
simulation verifies the correctness of the derived results and analyzes the
proposed capacity approximation quality performance
Interference Characterization in Multiple Access Wireless Networks
Contrarily to the point to point wireless link approach adopted in several wireless networks, where
a dedicated channel is usually supporting an exclusive-use wireless link, in the last years several
wireless communication systems have followed a different approach. In the so called “multiple
access wireless networks”, multiple transmitters share the same communication channel in a
simultaneous way, supporting a shared-use of the wireless link. The deployment of multiple access
networks has also originated the emergence of various communication networks operating in the
same geographical area and spectrum space, which is usually referred to as wireless coexistence.
As a consequence of the presence of multiple networks with different technologies that share the
same spectral bands, robust methods of interference management are needed. At the same time,
the adoption of in-band Full-duplex (IBFDX) communication schemes, in which a given node
transmit and receive simultaneously over the same frequency band, is seen as a disruptive topic in
multiple access networks, capable of doubling the network’s capacity.
Motivated by the importance of the interference in multiple access networks, this thesis addresses
new approaches to characterize the interference in multiple access networks. A special
focus is given to the assumption of mobility for the multiple transmitters. The problem of coexistence
interference caused by multiple networks operating in the same band is also considered.
Moreover, given the importance of the residual self-interference (SI) in practical IBFDX multiple
access networks, we study the distribution of the residual SI power in a wireless IBFDX
communication system. In addition, different applications of the proposed interference models
are presented, including the definition of a new sensing capacity metric for cognitive radio networks,
the performance evaluation of wireless-powered coexisting networks, the computation of
an optimal carrier-sensing range in coexisting CSMA networks, and the estimation of residual
self-interference in IBFDX communication systems
Statističke karakteristike prvog i drugog reda signala u bežičnom telekomunikacionom sistemu sa selekcionim kombinovanjem
In doctoral dissertation, first and second order system performances of wireless
communication system in the presence of fading and interference are considered.
Theoretically, four cases are taken into consideration, and obtained numerical results are
graphically presented and analyzed.
Firstly, wireless mobile communication system with the receiver that contains
automatic frequency control (AFC) loop operating over fading channel in the presence of
single interference is considered. Performance measures, such as average switching rate
(ASR) and mean time lose of lock (MTTL), are defined. In this doctoral dissertation, ASR
and MTTL, for three different fading channels: Kg, α-μ and k-μ are obtained.
In the next chapter, wireless relay communication system with two sections in the
presence of multipath fading is considered. Signal envelope at the input of the receiver can
be expressed as product of the first section signal envelope and the second section signal
envelope. For such system model, average level crossing rate (LCR) for the case when
radio relay system of the first section operates over Nakagami-m fading environment and
second section operates over k-μ fading environment is obtained. Wireless relay system
with two sections in the presence of non-linear α-μ fading channel is than taken into
consideration. Moreover, radio relay system with two sections in the presence of multipath
fading and interference is also considered. LCR of the ratio of the product of two k-μ
random processes and k-μ random process is calculated. Finally, LCR of the ratio of
Rician random process and product of two Rician random processes is obtained.
Wireless communication system with two inputs SSC diversity receiver operating
over correlated multipath η-μ fading in the presence of interference is than considered.
Joint probability density function and joint distribution cumulative function of the ratios of
signal to interference at inputs of SSC receivers are calculated. By using obtained
expressions for probability density function (PDF), average bit error probability (ABER)
for different coherent and non-coherent modulation schemes is obtained while by using
derived cumulative distribution function (CDF), outage probability (OP) is obtained.
At the end of doctoral dissertation, macrodiversity system with macrodiversity
SSC receiver and two microdiversity SC receivers operating over Gamma shadowed
multipath fading channel is proposed. In one case Nakagami-m multipath fading channel is
considered while in the second case k-μ multipath fading is considered. System
performances of the proposed system are derived and numerical results are graphically
presented and discusse
Recent Advances in Wireless Communications and Networks
This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides "real-time" research progress on these issues. The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level. This book also maintains the balance between current research results and their theoretical support. In this book, a variety of novel techniques in wireless communications and networks are investigated. The authors attempt to present these topics in detail. Insightful and reader-friendly descriptions are presented to nourish readers of any level, from practicing and knowledgeable communication engineers to beginning or professional researchers. All interested readers can easily find noteworthy materials in much greater detail than in previous publications and in the references cited in these chapters