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A hybrid approach for mobile location estimation in cellular radio networksChu, Man Kin 01 January 2006 (has links)
No description available.
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On optimization of the resource allocation in multi-cell networks.January 2009 (has links)
Chen, Jieying. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 58-62). / Abstract in English only. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Literature Review --- p.5 / Chapter 1.3 --- Contributions Of This Thesis --- p.7 / Chapter 1.4 --- Structure Of This Thesis --- p.8 / Chapter 2 --- Problem Formulation --- p.9 / Chapter 2.1 --- The JBAPC Problem --- p.9 / Chapter 2.2 --- The Single-Stage Reformulation --- p.12 / Chapter 3 --- The BARN Algorithm --- p.15 / Chapter 3.1 --- Preliminary Mathematics --- p.15 / Chapter 3.1.1 --- Duality Of The Linear Optimization Problem --- p.15 / Chapter 3.1.2 --- Benders Decomposition --- p.18 / Chapter 3.2 --- Solving The JBAPC Problem Using BARN Algorithm --- p.21 / Chapter 3.3 --- Performance And Convergence --- p.24 / Chapter 3.3.1 --- Global Convergence --- p.26 / Chapter 3.3.2 --- BARN With Error Tolerance --- p.26 / Chapter 3.3.3 --- Trade-off Between Performance And Convergence Time --- p.26 / Chapter 4 --- Accelerating BARN --- p.30 / Chapter 4.1 --- The Relaxed Master Problem --- p.30 / Chapter 4.2 --- The Feasibility Pump Method --- p.32 / Chapter 4.3 --- A-BARN Algorithm For Solving The JBAPC Problem --- p.34 / Chapter 5 --- Computational Results --- p.36 / Chapter 5.1 --- Global Optimality And Convergence --- p.36 / Chapter 5.2 --- Average Convergence Time --- p.37 / Chapter 5.3 --- Trade-off Between Performance And Convergence Time --- p.38 / Chapter 5.4 --- Average Algorithm Performance Of BARN and A-BARN --- p.39 / Chapter 6 --- Discussions --- p.47 / Chapter 6.1 --- Resource Allocation In The Uplink Multi-cell Networks --- p.47 / Chapter 6.2 --- JBAPC Problem In The Uplink Multi-cell Networks --- p.48 / Chapter 7 --- Conclusion --- p.50 / Chapter 7.1 --- Conclusion Of This Thesis --- p.50 / Chapter 7.2 --- Future Work --- p.51 / Chapter A --- The Proof --- p.52 / Chapter A.l --- Proof of Lemma 1 --- p.52 / Chapter A.2 --- Proof of Lemma 3 --- p.55 / Bibliography --- p.58
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Enhancing macrocell downlink performance through femtocell user cooperationZaid, Adem Mabruk 28 November 2011 (has links)
This thesis studies cooperative techniques that rely on femtocell user diversity to improve the downlink communication quality of macrocell users. We analytically analyze and evaluate the achievable performance of these techniques in the downlink of Rayleigh fading channels. We provide an approximation of both the bit-error rate (BER) and the data throughput that macrocell users receive with femtocell user cooperation. Using simulations, we show that under reasonable SNR values, cooperative schemes enhance the performances of macrocells by improving the BER, outage probability, and data throughput of macrocell users significantly when
compared with the traditional, non-cooperative schemes. / Graduation date: 2012
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Assisted GPS solution in cellular networks /Lissai, Gidon. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references.
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Performance analysis of cellular networks.Rajaratnam, Myuran. January 2000 (has links)
Performance analysis in cellular networks is the determination of customer orientated grade-of-service parameters, such as call blocking and dropping probabilities, using the methods of stochastic theory. This stochastic theory analysis is built on certain assumptions regarding the arrival and service processes of user-offered calls in a network. In the past, cellular networks were analysed using the classical assumptions, Poisson call arrivals and negative exponential channel holding times, borrowed from earlier fixed network analysis. However, cellular networks are markedly different from fixed networks, in that, they afford the user a unique opportunity: the ability to communicate while on the move. User mobility and various other cellular network characteristics, such as customer-billing, cell· layout and hand·off mechanisms, generally invalidate the use of Poisson arrivals and negative exponential holding times. Recent measurements on live networks substantiate this view. Consequently, over the past few years, there has been a noticeable shift towards using more generalised arrival and service distributions in the performance analysis of cellular networks. However, two shortcomings with the resulting models are that they suffer from state space explosion and / or they represent hand off traffic as a state dependent mean arrival rate (thus ignoring the higher moments of the hand-off arrival process). This thesis's contribution to cellular network analysis is a moment-based approach that avoids full state space description but ensures that the hand-off arrival process is modelled beyond the first moment. The thesis considers a performance analysis model that is based on Poisson new call arrivals, generalised hand-off call arrivals and a variety of channel holding times. The thesis shows that the performance analysis of a cellular network may be loosely decomposed into three parts, a generic cell traffic characterising model, a generic cell traffic blocking model and a quality of service evaluation model. The cell traffic characterising model is employed to determine the mean and variance of hand-off traffic offered by a cell to its neighbour. The cell traffic-blocking model is used to detennine the blocking experienced by the various traffic streams offered to each cell. The quality of service evaluation part is essentially afued-point iteration of the cell traffic characterising and cell traffic blocking parts to determine customer orientated grade-of-service parameters such as blocking and dropping probabilities. The thesis also presents detailed mathematical models for user mobility modelling. Finally, the thesis provides extensive results to validate the proposed analysis and to illustrate the accuracy of the proposed analysis when compared to existing methods. / Thesis (Ph.D.)-University of Natal, Durban, 2000.
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Power and performance trade-off in DS-CDMA receivers based on adaptive LMS-MMSE multi-user detector.Wang, Qingsheng. January 2003 (has links)
Third generation cellular communication systems based on CDMA techniques have shown great scope for improvement in system capacity. Over the last decade, there has been significant interest in DS-CDMA detectors. The conventional detector, the optimal detector and a number of sub-optimal multi-user detectors (MUD) have been extensively analyzed in the literature. Recently, the reduction of power consumption in DS-CDMA systems has also become another important consideration in both system design and in implementation. In order to support wireless multimedia services, all CDMA-based systems for third generation systems have a large bandwidth and a high data rate, therefore the power consumed by the digital signal processor (DSP) is high. This thesis focuses on power consumption in the adaptive Minimum Mean Square Error (MMSE) detector which is based on the Least Mean Square (LMS) algorithm. This thesis presents a literature survey on MUD and adaptive filter algorithms. A system model of the quantized LMS-MMSE MUD is proposed and its performance is analyzed. The quantization effects in the finite precision LMS-MMSE adaptive MUD including the steady-state weight covariance, mean square error (MSE) and bit error rate (BER) versus wordlength of data and coefficient are investigated when both the data and filter coefficients are quantized. The effects of wordlength size on power consumption are investigated and the tradeoff between the power consumption and performance degradation and the optimal allocation of bits to data and to LMS coefficients under power constraint is presented. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.
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Downlink call admission control in mixed service CDMA cellular networks.Ramlakhan, Niven Bhimraj. January 2007 (has links)
Since the ascendance of CDMA (Code Division Multiple Access) as the generally accepted
multiple access technology of choice for next generation networks, the rate of development of
the wireless cellular communication industry has been phenomenal. Next generation wireless
cellular networks offer a myriad of voice, video, data and text based information services for the
future multimedia and information society. This mixed service scenario implies that the same
[mite resource i.e. the air interface must be shared amongst different classes of user, each with a
specific quality of service. With multiple services competing for the same resource and with the
inherent soft capacity nature of CDMA, call admission control becomes a formidable task. The
problem is further compounded by the introduction of priorities between classes. Call admission
control is an essential component of these next generation networks and the open nature of the
current standards, such as UMTS (Universal Mobile Telecommunication System) allow for
vendor implementation of different call admission control policies.
The main area of focus in this dissertation is on a proposed downlink, load-based, mixed service
call admission policy. In a CDMA environment with symmetrical service and equal bandwidths
in each direction, the uplink is commonly considered to be the bottleneck. Based on the
asymmetric nature of the expected traffic in next generation networks the downlink is envisaged
as the future bottleneck. Some of the more common choices for downlink call admission control
include number based as well as power based call admission policies. A load-based call
admission policy has been chosen as the maximum load threshold that can be supported varies
with the state of the system and thus effectively models the behaviour of a soft capacity CDMA
network. This dissertation presents a teletraffic performance analysis model of a load-based call
admission control policy for downlink mixed service CDMA cellular networks.
The performance analysis yields customer oriented grade-of-service parameters such as call
blocking probability which is essential for network planning. In our analysis we incorporate a
Birth-Death Markov queuing model. This mathematical model is verified though computer
simulation. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2007.
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SenMinCom pervasive distributed dynamic sensor data mining for effective commerce /Hiremath, Naveen. January 2008 (has links)
Thesis (M.S.)--Georgia State University, 2008. / Title from file title page. Yanqing Zhang, committee chair; Rajshekhar Sunderraman, Ying Zhu, committee members. Electronic text (64 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Nov. 19, 2008. Includes bibliographical references (p. 59-64).
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Dynamic frequency hopping in cellular fixed relay networks /Mubarek, Ömer, January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 91-94). Also available in electronic format on the Internet.
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Mapping the impact of vegetation and terrain on cellular signal levelsTapp, Anna F. January 1900 (has links)
Thesis (M.A.)--The University of North Carolina at Greensboro, 2008. / Directed by Rick Bunch; submitted to the Dept. of Geography. Title from PDF t.p. (viewed Sep. 3, 2009). Includes bibliographical references (p. 48-53).
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