Distributed Power Control in Cellular and Wireless Networks - A Comparative Study
|
|
- Eileen Leonard
- 5 years ago
- Views:
Transcription
1 Distributed Power Control in Cellular and Wireless Networks - A Comparative Study Vijay Raman, ECE, UIUC 1 Why power control? Interference in communication systems restrains system capacity In cellular systems - cochannel interference due to channel reuse In wireless networks - interference from neighboring nodes due to uncoordinated access Interference mitigation procedures involve: Designing systems to tolerate low signal-to-noise ratio by using, for eg., efficient modulation and coding schemes Efficient cell planning - in case of cellular systems Dynamic channel allocation based on traffic and propagation conditions - for cellular and multichannel wireless networks Power control to reduce the effect of interference - can be done in addition to above schemes 2 What is power control? Adjust the power of each transmitter for a given channel allocation such that the interference levels at the receiver locations are minimized. Requirement Maintaining adequate transmission quality on the intended communication 1
2 link is a default requirement Consequence Reducing transmit power at a certain link will make it vulnerable to more interference Power control problem is not trivial Notes: The transmit power of one user is directly proportional to the interference caused to other users. Therefore, decreasing transmit power will reduce the interference levels at the users. However, reducing the power levels may disrupt the communication link. The goal of the power control algorithm is to therefore reduce interference while maintaining adequate signal quality at the intended receiver. 3 Power control in cellular systems - Performance analysis 1 Quality of a communication link in cellular systems is usually measured in terms of carrier-to-interference (C/I) ratio Assuming a high capacity, interference limited system, the C/I ratio as perceived by a mobile in cell i is given by, Γ i = P rx,i where P rx,i is the received power at mobile i and I j is the interference from a cell j i 1 J. Zander, Performance of optimum transmit power control in cellular radio systems, IEEE Transactions on Vehicular Technology, Feb j i I j 2
3 4 Performance analysis (2/3) If P i is the transmit power by a base station in cell i and G ij is the link gain between a mobile in cell i and a base station in cell j, we get Γ i = G iip i G ij P j j i If there are Q cells operating on a same channel at a given instant, then where, Γ i = P i Q P j Z ij P i j=1 Z ij = G ij G ii is a stochastic variable denoting the normalized link gain Γ i will also be a stochastic variable 5 Performance analysis (3/3) The distribution of Γ is defined as, F (γ) = P r{γ γ} = 1 Q Q P r{γ j γ} = 1 Q j=1 Q F j (γ) j=1 If γ 0, called system protection ratio, is the minimum C/I ratio required for a successful transmission, then the performance measure is the interference probability, F (γ 0 ) = P r{γ γ 0 } Notes: Here, Γ indicates the C/I level at some randomly chosen mobile. Because the C/I level at a mobile is affected by all the Q co-channel cells, the distribution of Γ at a randomly chosen mobile is the weighted sum of the distributions of the C/I levels at all the co-channel cells. The weights are assumed to be the same ( 1 Q ) for all the cells, implying that all the cells affect equally. 3
4 6 Idea behind the power control algorithm Preposition 1 With probability one, there exists a unique maximum achievable C/I level The maximum is given by γ = max{γ P 0 : Γ i γ, i} γ = 1 λ 1 where λ is the largest eigen value of the matrix Z. The power vector P achieving this maximum is the eigen vector corresponding to λ The proof follows directly from Perron-Forbenius Theorem noting that Z is a non-negative matrix of full rank with probability one Notes: The following definition may be useful to understand the Preposition 1. The definition of achievable C/I level be stated as follows: The C/I level γ is achievable if there exists a power vector P 0 such that Γ i γ for all cells i. Based on this definition of achievable C/I levels, all that the preposition says is, there exists a unique maximum achievable C/I level. Furthermore, the unique maximum is in fact reached when the C/I levels are balanced such that Γ i = γ, i. By P 0 we mean that the powers are non-negative. Further, we can understand that if the maximum achievable C/I is non-zero then P cannot be zero for any i. Finally, Preposition 1 suggests for which C/I level the system is stable, i.e., the C/I balance could be reached. 7 Optimum power vector Preposition 2 At least one optimum power vector has the form, P i = 0, P i 0, i R i / R where R = {i : Γ i < γ 0 } 4
5 This implies that we can limit our search for optimum power vectors to those vectors with positive components for those cells where the required C/I is achieved Notes: From this preposition, we can understand that the optimum power vector does not guarantee the required C/I, γ 0 for all users. Instead, we have to shut off users that cannot achieve the required C/I level. This suggests a means by which a power control algorithm has to operate. The Preposition 1 should be applied to the subset of users so formed (after eliminating those users who have Γ i < γ 0 ), and see if the protection ration γ 0 can now be achieved for all the users. If not, we have to again shut-off few users, and continue so on! In other words γ in Preposition 1 is not same as γ 0. The power control algorithm tries to make γ at least as good as γ 0 (i.e, it tries to make γ γ 0 ) by eliminating users that cannot achieve γ 0. 8 Global power control algorithm The goal of the power control algorithm is to minimize the interference probability and find the optimum power vector P 0 to achieve the greatest C/I ratio, γ that all the mobiles are jointly capable of achieving Shut-off transmissions in those links that has a C/I level less than the protection ratio, for eg. by handing over to another cell 9 Implications Implementing such an algorithm is difficult as it assumes a global knowledge of the channel gains of all the links Estimating the channels gains require significant measurement effort Even if a measurement is possible, the amount of data required to be communicated to the controller would be enormous for a reasonably sized network Motivates a distributed implementation of the power control algorithm 5
6 However, handing over mobiles that do not have sufficient C/I may increase the interference in the cell to which it has been handed over. No means to address this problem yet Notes: When there is a hard handover, the centralized power control algorithm will work exactly as mentioned in the sections so far. When a mobile cannot achieve the protection ratio in a cell, then it will be handed over to another cell where the mobile may potentially achieve the protection ratio (which may be due to better link characteristics). 10 Distributed power control algorithm 2 Distributed algorithm involves controlling the transmit power of the mobiles and their corresponding base stations without involving some central controller C/I measurements in the cell itself would affect the transmit power in the cell The power control algorithm is again based on cell-removal technique based on the following balancing algorithm P ν+1 i where ν denotes time = βp ν i P (0) = P 0, ( ) P 0 > Γ (ν) i, β > 0 Notes: The distributed algorithm is implemented as follows: Each node starts with an initial equal power and measures the resulting C/I ratio. If the C/I values are greater than γ 0 for all the cells then the algorithm will stop. Else, the balancing algorithm described in the section is operated for some L steps. At an intermediate step if all the mobiles have C/I greater than the protection ration, then the algorithm stops. Otherwise, after L steps, the cell with the least initial C/I level is removed and the algorithm is repeated by reseting the power levels of all cells to an equal value. 2 J. Zander, Distributed cochannel interference control in cellular radio systems, IEEE Transactions on Vehicular Technology, Aug
7 11 Implications of the distributed algorithm If we assume a slow-fading multipath channel, the factors affecting the link gain Z will be mainly the large scale fading The gains can be considered constant for the duration of the algorithm if the algorithm converges within the coherence time of the shadow fading process. This in turn requires high C/I estimation rate Multipath channel variations may however, corrupt the measurements, which in turn will determine the maximum possible iteration rate C/I measurements are therefore slow and less accurate 12 Implications of the distributed algorithm Such an algorithm may be useful for cellular systems with large or moderate cell sizes, but more careful study is required for indoor and small cell scenarios (where propagation changes rapidly) Moreover, a completely distributed algorithm is not possible as knowledge of C/I is required for cell removal [J. Zander 92] Distributed algorithms where users evolve their powers unanimously to a desired prefixed target C/I ratio has been proposed in the literature 3 Notes: 1) The distributed algorithm is easier to implement than a centralized algorithm as it is computationally simpler (as computations are distributed) and can operate with limited knowledge of the channel states (rather than a system-wide knowledge). 2) Because the distributed power control algorithm uses only a limited knowledge of the C/I values, it cannot be optimum. However, the distributed algorithm that is discussed approximates the centralized algorithm in the way it is formulated. The idea behind both the centralized and distributed algorithms are the same - eliminate users that cannot achieve the protection ratio. Though the centralized and the distributed schemes perform 3 G.J. Foschini and Z. Miljanic, A simple distributed autonomous power control algorithm and its convergence, IEEE Transactions on Vehicular Technology, Nov
8 Figure 1: Illustration of the carrier sense threshold this elimination based on the global view of the system, the main balancing procedure (discussed in Section 10), which is computationally intensive is distributed in the distributed algorithm. Furthermore, the cell-removal process can be implemented by proper co-ordination with the handoffs. 3) We have to understand that the distributed algorithm presented in this paper provides a framework for understanding the means for achieving an optimal (or near optimal) performance in cellular systems. However, these papers do not provide the means for fairness in the power control algorithms. A distributed power control scheme that addresses fairness is proposed by M. Xiao and Ness.B. Shroff in A Utility-Based Power Control Scheme in Wireless Cellular Systems (IEEE/ACM Transactions on Networking, April, 2003). 13 Power control in wireless networks Interference mitigation in IEEE type networks is mainly aimed at improving spatial reuse [J. A. Fuemmeler, N.H. Vaidya, and V.V. Veeravalli] Few power control algorithms focus on reducing energy consumption by wireless nodes [S. Agrawal, R.H. Katz, S.V. Krishnamurthy, and S.K. Dao] Carrier sensing in networks makes power control in WLANs to be dependent on another quantity called carrier sense threshold Notes: 1) Transmissions in ad-hoc networks are uncoordinated and random, 8
9 Figure 2: First order starvation in wireless networks rather than a coordinated and scheduled access as in the case of cellular systems. Therefore, power control in wireless networks is (in a sense) difficult than that in cellular systems. 2) The CS-threshold value will essentially let a mobile to decide whether to transmit or not. In other words, a mobile will transmit if the power received from some other (potentially interfering) mobile is lower than its CS-threshold. Thus, choosing the right CS-threshold value is important to make good transmit decision and thereby decide the number of simultaneous transmissions possible. Choosing a very high CS-threshold value may result in more simultaneous transmissions that may result in a collision (as the power of a colliding transmission will fall below the CS-threshold value, which therefore cannot be sensed by a mobile), while choosing a very small CS-threshold may result in a conservative system that will have very little simultaneous transmissions (as the power from a distant, potentially noncolliding transmission may still be above the CS-threshold, leading to a deferred transmission). 14 Key problems in power control 4 Asymmetric links Introduces first order starvation First order starvation can be avoided by achieving symmetry through joint tuning of transmit power and carrier sense threshold Suggested solution is to maintain the product of carrier sense threshold, p cs and transmit power, p t of a node constant, i.e., p cs p t = β 4 V.P. Mathre, K. Papagiannaki, and F. Baccelli, Interference mitigation through power control in high density WLANs, IEEE Infocom 07. 9
10 Figure 3: Second order starvation in wireless networks Interestingly, Fuemmeler, et al. arrive at the same solution for improving spatial reuse in ad-hoc networks Notes: The intuition behind setting p cs p t = β is that, when we reduce the transmit power will also come down. We can therefore have more simultaneous transmissions, which can be achieved by increasing the CS-threshold value of the mobiles (as discussed in the notes for the previous section). 15 Key problems in power control (2/2) Power control may still have to address the second order starvation Algorithms to address fully the second order starvation is an open problem 16 Discussions How to perform power control in macro-diverse wireless networks? Involves a dense deployment of access points to which a mobile client can interact [e.g., DAIR] R.D. Yates provides a power control framework for macrodiverse cellular systems Can we have the Access Points (APs) in wireless network interact among themselves to exchange power control information May include channel gains, traffic loads, CS threshold values (if not uniform), etc. 10
11 Possible in dense infrastructure-based networks How to perform power control when there are multiple channels? Power reduction for a user moving from channel c to c may increase the interference to users currently on channel c Notes: 1) A water-filling based power control algorithm is totally different from the algorithms that are discussed in this presentation. In water-filling, the users are all assumed to be independent and the powers are allocated to the users based on their noise levels, such that the total power allocated to all the users is less than a maximum available power. In wireless networks, the transmit power of one user will affect the interference to other users. 2) If the wireless nodes can exchange the information on their relative traffic load, channel gains, etc. then better power control decisions can be made. The mobiles can predict the potential interference better and use a more accurate transmit power to overcome the interference. 11
Joint Scheduling and Power Control for Wireless Ad-hoc Networks
Joint Scheduling and Power Control for Wireless Ad-hoc Networks Tamer ElBatt Network Analysis and Systems Dept. HRL Laboratories, LLC Malibu, CA 90265, USA telbatt@wins.hrl.com Anthony Ephremides Electrical
More informationEE 382C Literature Survey. Adaptive Power Control Module in Cellular Radio System. Jianhua Gan. Abstract
EE 382C Literature Survey Adaptive Power Control Module in Cellular Radio System Jianhua Gan Abstract Several power control methods in cellular radio system are reviewed. Adaptive power control scheme
More informationOn the Value of Coherent and Coordinated Multi-point Transmission
On the Value of Coherent and Coordinated Multi-point Transmission Antti Tölli, Harri Pennanen and Petri Komulainen atolli@ee.oulu.fi Centre for Wireless Communications University of Oulu December 4, 2008
More informationCross-layer Network Design for Quality of Services in Wireless Local Area Networks: Optimal Access Point Placement and Frequency Channel Assignment
Cross-layer Network Design for Quality of Services in Wireless Local Area Networks: Optimal Access Point Placement and Frequency Channel Assignment Chutima Prommak and Boriboon Deeka Abstract This paper
More informationSite Specific Knowledge for Improving Transmit Power Control in Wireless Networks
Site Specific Knowledge for Improving Transmit Power Control in Wireless Networks Jeremy K. Chen, Theodore S. Rappaport, and Gustavo de Veciana Wireless Networking and Communications Group (WNCG), The
More informationEasyChair Preprint. A User-Centric Cluster Resource Allocation Scheme for Ultra-Dense Network
EasyChair Preprint 78 A User-Centric Cluster Resource Allocation Scheme for Ultra-Dense Network Yuzhou Liu and Wuwen Lai EasyChair preprints are intended for rapid dissemination of research results and
More informationChutima Prommak and Boriboon Deeka. Proceedings of the World Congress on Engineering 2007 Vol II WCE 2007, July 2-4, 2007, London, U.K.
Network Design for Quality of Services in Wireless Local Area Networks: a Cross-layer Approach for Optimal Access Point Placement and Frequency Channel Assignment Chutima Prommak and Boriboon Deeka ESS
More information03_57_104_final.fm Page 97 Tuesday, December 4, :17 PM. Problems Problems
03_57_104_final.fm Page 97 Tuesday, December 4, 2001 2:17 PM Problems 97 3.9 Problems 3.1 Prove that for a hexagonal geometry, the co-channel reuse ratio is given by Q = 3N, where N = i 2 + ij + j 2. Hint:
More informationInterference Scenarios and Capacity Performances for Femtocell Networks
Interference Scenarios and Capacity Performances for Femtocell Networks Esra Aycan, Berna Özbek Electrical and Electronics Engineering Department zmir Institute of Technology, zmir, Turkey esraaycan@iyte.edu.tr,
More informationA Location-Aware Routing Metric (ALARM) for Multi-Hop, Multi-Channel Wireless Mesh Networks
A Location-Aware Routing Metric (ALARM) for Multi-Hop, Multi-Channel Wireless Mesh Networks Eiman Alotaibi, Sumit Roy Dept. of Electrical Engineering U. Washington Box 352500 Seattle, WA 98195 eman76,roy@ee.washington.edu
More informationDISTRIBUTED DYNAMIC CHANNEL ALLOCATION ALGORITHM FOR CELLULAR MOBILE NETWORK
DISTRIBUTED DYNAMIC CHANNEL ALLOCATION ALGORITHM FOR CELLULAR MOBILE NETWORK 1 Megha Gupta, 2 A.K. Sachan 1 Research scholar, Deptt. of computer Sc. & Engg. S.A.T.I. VIDISHA (M.P) INDIA. 2 Asst. professor,
More informationIntroduction to Wireless and Mobile Networking. Hung-Yu Wei g National Taiwan University
Introduction to Wireless and Mobile Networking Lecture 3: Multiplexing, Multiple Access, and Frequency Reuse Hung-Yu Wei g National Taiwan University Multiplexing/Multiple Access Multiplexing Multiplexing
More informationCHAPTER 10 CONCLUSIONS AND FUTURE WORK 10.1 Conclusions
CHAPTER 10 CONCLUSIONS AND FUTURE WORK 10.1 Conclusions This dissertation reported results of an investigation into the performance of antenna arrays that can be mounted on handheld radios. Handheld arrays
More informationDownlink Erlang Capacity of Cellular OFDMA
Downlink Erlang Capacity of Cellular OFDMA Gauri Joshi, Harshad Maral, Abhay Karandikar Department of Electrical Engineering Indian Institute of Technology Bombay Powai, Mumbai, India 400076. Email: gaurijoshi@iitb.ac.in,
More informationCognitive Wireless Network : Computer Networking. Overview. Cognitive Wireless Networks
Cognitive Wireless Network 15-744: Computer Networking L-19 Cognitive Wireless Networks Optimize wireless networks based context information Assigned reading White spaces Online Estimation of Interference
More informationAbstract. Marío A. Bedoya-Martinez. He joined Fujitsu Europe Telecom R&D Centre (UK), where he has been working on R&D of Second-and
Abstract The adaptive antenna array is one of the advanced techniques which could be implemented in the IMT-2 mobile telecommunications systems to achieve high system capacity. In this paper, an integrated
More informationPower Control and Utility Optimization in Wireless Communication Systems
Power Control and Utility Optimization in Wireless Communication Systems Dimitrie C. Popescu and Anthony T. Chronopoulos Electrical Engineering Dept. Computer Science Dept. University of Texas at San Antonio
More informationA Game-Theoretic Analysis of Uplink Power Control for a Non-Orthogonal Multiple Access System with Two Interfering Cells
A Game-Theoretic Analysis of Uplink Power Control for a on-orthogonal Multiple Access System with Two Interfering Cells Chi Wan Sung City University of Hong Kong Tat Chee Avenue, Kowloon, Hong Kong Email:
More informationDiversity Techniques
Diversity Techniques Vasileios Papoutsis Wireless Telecommunication Laboratory Department of Electrical and Computer Engineering University of Patras Patras, Greece No.1 Outline Introduction Diversity
More informationUNIT-II 1. Explain the concept of frequency reuse channels. Answer:
UNIT-II 1. Explain the concept of frequency reuse channels. Concept of Frequency Reuse Channels: A radio channel consists of a pair of frequencies one for each direction of transmission that is used for
More information6 Uplink is from the mobile to the base station.
It is well known that by using the directional properties of adaptive arrays, the interference from multiple users operating on the same channel as the desired user in a time division multiple access (TDMA)
More informationA survey on broadcast protocols in multihop cognitive radio ad hoc network
A survey on broadcast protocols in multihop cognitive radio ad hoc network Sureshkumar A, Rajeswari M Abstract In the traditional ad hoc network, common channel is present to broadcast control channels
More informationITLinQ: A New Approach for Spectrum Sharing in Device-to-Device Networks
ITLinQ: A New Approach for Spectrum Sharing in Device-to-Device Networks Salman Avestimehr In collaboration with Navid Naderializadeh ITA 2/10/14 D2D Communication Device-to-Device (D2D) communication
More informationUNEQUAL POWER ALLOCATION FOR JPEG TRANSMISSION OVER MIMO SYSTEMS. Muhammad F. Sabir, Robert W. Heath Jr. and Alan C. Bovik
UNEQUAL POWER ALLOCATION FOR JPEG TRANSMISSION OVER MIMO SYSTEMS Muhammad F. Sabir, Robert W. Heath Jr. and Alan C. Bovik Department of Electrical and Computer Engineering, The University of Texas at Austin,
More informationFrequency and Power Allocation for Low Complexity Energy Efficient OFDMA Systems with Proportional Rate Constraints
Frequency and Power Allocation for Low Complexity Energy Efficient OFDMA Systems with Proportional Rate Constraints Pranoti M. Maske PG Department M. B. E. Society s College of Engineering Ambajogai Ambajogai,
More informationSmart antenna technology
Smart antenna technology In mobile communication systems, capacity and performance are usually limited by two major impairments. They are multipath and co-channel interference [5]. Multipath is a condition
More informationENERGY EFFICIENT WATER-FILLING ALGORITHM FOR MIMO- OFDMA CELLULAR SYSTEM
ENERGY EFFICIENT WATER-FILLING ALGORITHM FOR MIMO- OFDMA CELLULAR SYSTEM Hailu Belay Kassa, Dereje H.Mariam Addis Ababa University, Ethiopia Farzad Moazzami, Yacob Astatke Morgan State University Baltimore,
More informationTHE EFFECT of multipath fading in wireless systems can
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 47, NO. 1, FEBRUARY 1998 119 The Diversity Gain of Transmit Diversity in Wireless Systems with Rayleigh Fading Jack H. Winters, Fellow, IEEE Abstract In
More informationEFFICIENT SMART ANTENNA FOR 4G COMMUNICATIONS
http:// EFFICIENT SMART ANTENNA FOR 4G COMMUNICATIONS 1 Saloni Aggarwal, 2 Neha Kaushik, 3 Deeksha Sharma 1,2,3 UG, Department of Electronics and Communication Engineering, Raj Kumar Goel Institute of
More informationFrom. Power Control for Reliable M2M Communication. Ling Wang Wayne State University. Hongwei Zhang Wayne State University CONTENTS
CHAPTER1 Power Control for Reliable M2M Communication Ling Wang Wayne State University Hongwei Zhang Wayne State University CONTENTS 1.1 Introduction... 4 1.1.1 History of power control in cellular networks...
More informationPower Controlled Random Access
1 Power Controlled Random Access Aditya Dua Department of Electrical Engineering Stanford University Stanford, CA 94305 dua@stanford.edu Abstract The lack of an established infrastructure, and the vagaries
More informationPartial overlapping channels are not damaging
Journal of Networking and Telecomunications (2018) Original Research Article Partial overlapping channels are not damaging Jing Fu,Dongsheng Chen,Jiafeng Gong Electronic Information Engineering College,
More informationPerformance Evaluation of Uplink Closed Loop Power Control for LTE System
Performance Evaluation of Uplink Closed Loop Power Control for LTE System Bilal Muhammad and Abbas Mohammed Department of Signal Processing, School of Engineering Blekinge Institute of Technology, Ronneby,
More informationJoint Power Control, Beamforming and BS Assignment for Optimal SIR Assignment
Joint Power Control, Beamforming and BS Assignment for Optimal SIR Assignment Yosia Hadisusanto, Lars Thiele and Volker Jungnickel Fraunhofer German-Sino Lab Mobile Communications MCI) Einsteinufer 37,
More informationWireless Networked Systems
Wireless Networked Systems CS 795/895 - Spring 2013 Lec #4: Medium Access Control Power/CarrierSense Control, Multi-Channel, Directional Antenna Tamer Nadeem Dept. of Computer Science Power & Carrier Sense
More informationA Game-Theoretic Framework for Interference Avoidance in Ad hoc Networks
A Game-Theoretic Framework for Interference Avoidance in Ad hoc Networks R. Menon, A. B. MacKenzie, R. M. Buehrer and J. H. Reed The Bradley Department of Electrical and Computer Engineering Virginia Tech,
More information3432 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 53, NO. 10, OCTOBER 2007
3432 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL 53, NO 10, OCTOBER 2007 Resource Allocation for Wireless Fading Relay Channels: Max-Min Solution Yingbin Liang, Member, IEEE, Venugopal V Veeravalli, Fellow,
More informationOptimal Power Allocation and Scheduling for Two-Cell Capacity Maximization
Optimal Power Allocation and Scheduling for Two-Cell Capacity Maximization Anders Gjendemsjø, David Gesbert, Geir E. Øien, and Saad G. Kiani Dept. of Electronics and Telecom., Norwegian Univ. of Science
More informationPerformance Analysis of Power Control and Cell Association in Heterogeneous Cellular Networks
Performance Analysis of Power Control and Cell Association in Heterogeneous Cellular Networks Prasanna Herath Mudiyanselage PhD Final Examination Supervisors: Witold A. Krzymień and Chintha Tellambura
More informationResource Allocation Strategies Based on the Signal-to-Leakage-plus-Noise Ratio in LTE-A CoMP Systems
Resource Allocation Strategies Based on the Signal-to-Leakage-plus-Noise Ratio in LTE-A CoMP Systems Rana A. Abdelaal Mahmoud H. Ismail Khaled Elsayed Cairo University, Egypt 4G++ Project 1 Agenda Motivation
More informationLevel 6 Graduate Diploma in Engineering Wireless and mobile communications
9210-119 Level 6 Graduate Diploma in Engineering Wireless and mobile communications Sample Paper You should have the following for this examination one answer book non-programmable calculator pen, pencil,
More informationEfficient Method of Secondary Users Selection Using Dynamic Priority Scheduling
Efficient Method of Secondary Users Selection Using Dynamic Priority Scheduling ABSTRACT Sasikumar.J.T 1, Rathika.P.D 2, Sophia.S 3 PG Scholar 1, Assistant Professor 2, Professor 3 Department of ECE, Sri
More informationOptimal Utility-Based Resource Allocation for OFDM Networks with Multiple Types of Traffic
Optimal Utility-Based Resource Allocation for OFDM Networks with Multiple Types of Traffic Mohammad Katoozian, Keivan Navaie Electrical and Computer Engineering Department Tarbiat Modares University, Tehran,
More informationK.NARSING RAO(08R31A0425) DEPT OF ELECTRONICS & COMMUNICATION ENGINEERING (NOVH).
Smart Antenna K.NARSING RAO(08R31A0425) DEPT OF ELECTRONICS & COMMUNICATION ENGINEERING (NOVH). ABSTRACT:- One of the most rapidly developing areas of communications is Smart Antenna systems. This paper
More informationHow (Information Theoretically) Optimal Are Distributed Decisions?
How (Information Theoretically) Optimal Are Distributed Decisions? Vaneet Aggarwal Department of Electrical Engineering, Princeton University, Princeton, NJ 08544. vaggarwa@princeton.edu Salman Avestimehr
More informationSmart Antenna ABSTRACT
Smart Antenna ABSTRACT One of the most rapidly developing areas of communications is Smart Antenna systems. This paper deals with the principle and working of smart antennas and the elegance of their applications
More informationSimple, Optimal, Fast, and Robust Wireless Random Medium Access Control
Simple, Optimal, Fast, and Robust Wireless Random Medium Access Control Jianwei Huang Department of Information Engineering The Chinese University of Hong Kong KAIST-CUHK Workshop July 2009 J. Huang (CUHK)
More informationMultihop Relay-Enhanced WiMAX Networks
0 Multihop Relay-Enhanced WiMAX Networks Yongchul Kim and Mihail L. Sichitiu Department of Electrical and Computer Engineering North Carolina State University Raleigh, NC 27695 USA. Introduction The demand
More informationTransmission Performance of Flexible Relay-based Networks on The Purpose of Extending Network Coverage
Transmission Performance of Flexible Relay-based Networks on The Purpose of Extending Network Coverage Ardian Ulvan 1 and Robert Bestak 1 1 Czech Technical University in Prague, Technicka 166 7 Praha 6,
More informationCollaborative transmission in wireless sensor networks
Collaborative transmission in wireless sensor networks Cooperative transmission schemes Stephan Sigg Distributed and Ubiquitous Systems Technische Universität Braunschweig November 22, 2010 Stephan Sigg
More informationPerformance of ALOHA and CSMA in Spatially Distributed Wireless Networks
Performance of ALOHA and CSMA in Spatially Distributed Wireless Networks Mariam Kaynia and Nihar Jindal Dept. of Electrical and Computer Engineering, University of Minnesota Dept. of Electronics and Telecommunications,
More informationMultiple Antenna Processing for WiMAX
Multiple Antenna Processing for WiMAX Overview Wireless operators face a myriad of obstacles, but fundamental to the performance of any system are the propagation characteristics that restrict delivery
More informationAntennas and Propagation. Chapter 6b: Path Models Rayleigh, Rician Fading, MIMO
Antennas and Propagation b: Path Models Rayleigh, Rician Fading, MIMO Introduction From last lecture How do we model H p? Discrete path model (physical, plane waves) Random matrix models (forget H p and
More informationUniversity of Würzburg Institute of Computer Science Research Report Series. Diversity Effects on the Soft Handover Gain in UMTS networks
University of Würzburg Institute of Computer Science Research Report Series Diversity Effects on the Soft Handover Gain in UMTS networks Klaus Heck, Dirk Staehle, and Kenji Leibnitz Report No. 295 April
More informationA Joint Solution to Scheduling and Power Control for Multicasting in Wireless Ad Hoc Networks
EURASIP Journal on Applied Signal Processing 2005:2, 144 152 c 2005 Hindawi Publishing Corporation A Joint Solution to Scheduling and Power Control for Multicasting in Wireless Ad Hoc Networks Kang Wang
More informationDynamic Cell Association for Non-Orthogonal Multiple-Access V2S Networks
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI.9/JAC.27.272578,
More informationA Heuristic Algorithm for Joint Power-Delay Minimization in Green Wireless Access Networks
A Heuristic Algorithm for Joint Power-Delay Minimization in Green Wireless Access Networks Farah Moety, Samer Lahoud, Bernard Cousin, Kinda Khawam University of Rennes I - IRISA, France University of Versailles
More informationAverage Delay in Asynchronous Visual Light ALOHA Network
Average Delay in Asynchronous Visual Light ALOHA Network Xin Wang, Jean-Paul M.G. Linnartz, Signal Processing Systems, Dept. of Electrical Engineering Eindhoven University of Technology The Netherlands
More informationWireless ad hoc networks. Acknowledgement: Slides borrowed from Richard Y. Yale
Wireless ad hoc networks Acknowledgement: Slides borrowed from Richard Y. Yang @ Yale Infrastructure-based v.s. ad hoc Infrastructure-based networks Cellular network 802.11, access points Ad hoc networks
More informationPERFORMANCE OF DISTRIBUTED UTILITY-BASED POWER CONTROL FOR WIRELESS AD HOC NETWORKS
PERFORMANCE OF DISTRIBUTED UTILITY-BASED POWER CONTROL FOR WIRELESS AD HOC NETWORKS Jianwei Huang, Randall Berry, Michael L. Honig Department of Electrical and Computer Engineering Northwestern University
More informationDistributed and Coordinated Spectrum Access Methods for Heterogeneous Channel Bonding
Distributed and Coordinated Spectrum Access Methods for Heterogeneous Channel Bonding 1 Zaheer Khan, Janne Lehtomäki, Simon Scott, Zhu Han, Marwan Krunz, and Alan Marshall Abstract Channel bonding (CB)
More information3644 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 57, NO. 6, JUNE 2011
3644 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 57, NO. 6, JUNE 2011 Asynchronous CSMA Policies in Multihop Wireless Networks With Primary Interference Constraints Peter Marbach, Member, IEEE, Atilla
More informationOFDM Pilot Optimization for the Communication and Localization Trade Off
SPCOMNAV Communications and Navigation OFDM Pilot Optimization for the Communication and Localization Trade Off A. Lee Swindlehurst Dept. of Electrical Engineering and Computer Science The Henry Samueli
More informationStarvation Mitigation Through Multi-Channel Coordination in CSMA Multi-hop Wireless Networks
Starvation Mitigation Through Multi-Channel Coordination in CSMA Multi-hop Wireless Networks Jingpu Shi Theodoros Salonidis Edward Knightly Networks Group ECE, University Simulation in single-channel multi-hop
More informationColor of Interference and Joint Encoding and Medium Access in Large Wireless Networks
Color of Interference and Joint Encoding and Medium Access in Large Wireless Networks Nithin Sugavanam, C. Emre Koksal, Atilla Eryilmaz Department of Electrical and Computer Engineering The Ohio State
More informationISSN Vol.03,Issue.17 August-2014, Pages:
www.semargroup.org, www.ijsetr.com ISSN 2319-8885 Vol.03,Issue.17 August-2014, Pages:3542-3548 Implementation of MIMO Multi-Cell Broadcast Channels Based on Interference Alignment Techniques B.SANTHOSHA
More informationSPECTRUM resources are scarce and fixed spectrum allocation
Hedonic Coalition Formation Game for Cooperative Spectrum Sensing and Channel Access in Cognitive Radio Networks Xiaolei Hao, Man Hon Cheung, Vincent W.S. Wong, Senior Member, IEEE, and Victor C.M. Leung,
More informationSystem Level Simulations for Cellular Networks Using MATLAB
System Level Simulations for Cellular Networks Using MATLAB Sriram N. Kizhakkemadam, Swapnil Vinod Khachane, Sai Chaitanya Mantripragada Samsung R&D Institute Bangalore Cellular Systems Cellular Network:
More informationDeployment scenarios and interference analysis using V-band beam-steering antennas
Deployment scenarios and interference analysis using V-band beam-steering antennas 07/2017 Siklu 2017 Table of Contents 1. V-band P2P/P2MP beam-steering motivation and use-case... 2 2. Beam-steering antenna
More informationTHE emergence of multiuser transmission techniques for
IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 54, NO. 10, OCTOBER 2006 1747 Degrees of Freedom in Wireless Multiuser Spatial Multiplex Systems With Multiple Antennas Wei Yu, Member, IEEE, and Wonjong Rhee,
More informationA MAC protocol for full exploitation of Directional Antennas in Ad-hoc Wireless Networks
A MAC protocol for full exploitation of Directional Antennas in Ad-hoc Wireless Networks Thanasis Korakis Gentian Jakllari Leandros Tassiulas Computer Engineering and Telecommunications Department University
More informationAchievable-SIR-Based Predictive Closed-Loop Power Control in a CDMA Mobile System
720 IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 51, NO. 4, JULY 2002 Achievable-SIR-Based Predictive Closed-Loop Power Control in a CDMA Mobile System F. C. M. Lau, Member, IEEE and W. M. Tam Abstract
More informationIncreasing Broadcast Reliability for Vehicular Ad Hoc Networks. Nathan Balon and Jinhua Guo University of Michigan - Dearborn
Increasing Broadcast Reliability for Vehicular Ad Hoc Networks Nathan Balon and Jinhua Guo University of Michigan - Dearborn I n t r o d u c t i o n General Information on VANETs Background on 802.11 Background
More informationWIRELESS communication channels vary over time
1326 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 51, NO. 4, APRIL 2005 Outage Capacities Optimal Power Allocation for Fading Multiple-Access Channels Lifang Li, Nihar Jindal, Member, IEEE, Andrea Goldsmith,
More informationA New Adaptive Channel Estimation for Frequency Selective Time Varying Fading OFDM Channels
A New Adaptive Channel Estimation for Frequency Selective Time Varying Fading OFDM Channels Wessam M. Afifi, Hassan M. Elkamchouchi Abstract In this paper a new algorithm for adaptive dynamic channel estimation
More informationOptimal Resource Allocation in Multihop Relay-enhanced WiMAX Networks
Optimal Resource Allocation in Multihop Relay-enhanced WiMAX Networks Yongchul Kim and Mihail L. Sichitiu Department of Electrical and Computer Engineering North Carolina State University Email: yckim2@ncsu.edu
More informationFrequency-Hopped Spread-Spectrum
Chapter Frequency-Hopped Spread-Spectrum In this chapter we discuss frequency-hopped spread-spectrum. We first describe the antijam capability, then the multiple-access capability and finally the fading
More informationOn Coding for Cooperative Data Exchange
On Coding for Cooperative Data Exchange Salim El Rouayheb Texas A&M University Email: rouayheb@tamu.edu Alex Sprintson Texas A&M University Email: spalex@tamu.edu Parastoo Sadeghi Australian National University
More informationAutomatic power/channel management in Wi-Fi networks
Automatic power/channel management in Wi-Fi networks Jan Kruys Februari, 2016 This paper was sponsored by Lumiad BV Executive Summary The holy grail of Wi-Fi network management is to assure maximum performance
More informationSmart Antenna Techniques and Their Application to Wireless Ad Hoc Networks. Plenary Talk at: Jack H. Winters. September 13, 2005
Smart Antenna Techniques and Their Application to Wireless Ad Hoc Networks Plenary Talk at: Jack H. Winters September 13, 2005 jwinters@motia.com 12/05/03 Slide 1 1 Outline Service Limitations Smart Antennas
More informationAd Hoc Resource Allocation in Cellular Systems
Appears in Proceedings of 1999 IEEE Radio and Wireless Conference (RAWCON99), pg. 51. Ad Hoc Resource Allocation in Cellular Systems Abstract A fundamental question in a wireless cellular system is how
More informationInternational Journal of Scientific & Engineering Research, Volume 6, Issue 4, April-2015 ISSN
258 Intelligent Closed Loop Power Control For Reverse Link CDMA System Using Fuzzy Logic System. K.Sanmugapriyaa II year, M.E-Communication System Department of ECE Paavai Engineering College Namakkal,India
More informationAdaptive Channel Allocation in OFDM/SDMA Wireless LANs with Limited Transceiver Resources
Adaptive Channel Allocation in OFDM/SDMA Wireless LANs with Limited Transceiver Resources Iordanis Koutsopoulos and Leandros Tassiulas Department of Computer and Communications Engineering, University
More informationIntelligent Handoff in Cellular Data Networks Based on Mobile Positioning
Intelligent Handoff in Cellular Data Networks Based on Mobile Positioning Prasannakumar J.M. 4 th semester MTech (CSE) National Institute Of Technology Karnataka Surathkal 575025 INDIA Dr. K.C.Shet Professor,
More informationIN recent years, there has been great interest in the analysis
2890 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 52, NO. 7, JULY 2006 On the Power Efficiency of Sensory and Ad Hoc Wireless Networks Amir F. Dana, Student Member, IEEE, and Babak Hassibi Abstract We
More informationChapter 2 Distributed Consensus Estimation of Wireless Sensor Networks
Chapter 2 Distributed Consensus Estimation of Wireless Sensor Networks Recently, consensus based distributed estimation has attracted considerable attention from various fields to estimate deterministic
More informationDynamic Subcarrier, Bit and Power Allocation in OFDMA-Based Relay Networks
Dynamic Subcarrier, Bit and Power Allocation in OFDMA-Based Relay Networs Christian Müller*, Anja Klein*, Fran Wegner**, Martin Kuipers**, Bernhard Raaf** *Communications Engineering Lab, Technische Universität
More informationOpportunistic Scheduling: Generalizations to. Include Multiple Constraints, Multiple Interfaces,
Opportunistic Scheduling: Generalizations to Include Multiple Constraints, Multiple Interfaces, and Short Term Fairness Sunil Suresh Kulkarni, Catherine Rosenberg School of Electrical and Computer Engineering
More informationVOL. 3, NO.11 Nov, 2012 ISSN Journal of Emerging Trends in Computing and Information Sciences CIS Journal. All rights reserved.
Effect of Fading Correlation on the Performance of Spatial Multiplexed MIMO systems with circular antennas M. A. Mangoud Department of Electrical and Electronics Engineering, University of Bahrain P. O.
More informationSEN366 (SEN374) (Introduction to) Computer Networks
SEN366 (SEN374) (Introduction to) Computer Networks Prof. Dr. Hasan Hüseyin BALIK (8 th Week) Cellular Wireless Network 8.Outline Principles of Cellular Networks Cellular Network Generations LTE-Advanced
More informationIEEE/ACM TRANSACTIONS ON NETWORKING, VOL. XX, NO. X, AUGUST 20XX 1
IEEE/ACM TRANSACTIONS ON NETWORKING, VOL. XX, NO. X, AUGUST 0XX 1 Greenput: a Power-saving Algorithm That Achieves Maximum Throughput in Wireless Networks Cheng-Shang Chang, Fellow, IEEE, Duan-Shin Lee,
More informationOn the Optimum Power Allocation in the One-Side Interference Channel with Relay
2012 IEEE Wireless Communications and etworking Conference: Mobile and Wireless etworks On the Optimum Power Allocation in the One-Side Interference Channel with Relay Song Zhao, Zhimin Zeng, Tiankui Zhang
More informationGeometric Analysis of Distributed Power Control and Möbius MAC Design
WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Wirel. Commun. Mob. Comput. 21; :1 29 RESEARCH ARTICLE Geometric Analysis of Distributed Power Control and Möbius MAC Design Zhen Tong 1 and Martin Haenggi
More informationSNS COLLEGE OF ENGINEERING COIMBATORE DEPARTMENT OF INFORMATION TECHNOLOGY QUESTION BANK
SNS COLLEGE OF ENGINEERING COIMBATORE 641107 DEPARTMENT OF INFORMATION TECHNOLOGY QUESTION BANK EC6801 WIRELESS COMMUNICATION UNIT-I WIRELESS CHANNELS PART-A 1. What is propagation model? 2. What are the
More informationPerformances Analysis of Different Channel Allocation Schemes for Personal Mobile Communication Networks
Performances Analysis of Different Channel Allocation Schemes for Personal Mobile Communication Networks 1 GABRIEL SIRBU, ION BOGDAN 1 Electrical and Electronics Engineering Dept., Telecommunications Dept.
More informationPower Control Algorithm for Providing Packet Error Rate Guarantees in Ad-Hoc Networks
Proceedings of the 44th IEEE Conference on Decision and Control, and the European Control Conference 2005 Seville, Spain, December 12-15, 2005 WeC14.5 Power Control Algorithm for Providing Packet Error
More informationCellular systems 02/10/06
Cellular systems 02/10/06 Cellular systems Implements space division multiplex: base station covers a certain transmission area (cell) Mobile stations communicate only via the base station Cell sizes from
More informationAdaptive Transmission Scheme for Vehicle Communication System
Sangmi Moon, Sara Bae, Myeonghun Chu, Jihye Lee, Soonho Kwon and Intae Hwang Dept. of Electronics and Computer Engineering, Chonnam National University, 300 Yongbongdong Bukgu Gwangju, 500-757, Republic
More informationDistributed Game Theoretic Optimization Of Frequency Selective Interference Channels: A Cross Layer Approach
2010 IEEE 26-th Convention of Electrical and Electronics Engineers in Israel Distributed Game Theoretic Optimization Of Frequency Selective Interference Channels: A Cross Layer Approach Amir Leshem and
More informationPERFORMANCE OF POWER DECENTRALIZED DETECTION IN WIRELESS SENSOR SYSTEM WITH DS-CDMA
PERFORMANCE OF POWER DECENTRALIZED DETECTION IN WIRELESS SENSOR SYSTEM WITH DS-CDMA Ali M. Fadhil 1, Haider M. AlSabbagh 2, and Turki Y. Abdallah 1 1 Department of Computer Engineering, College of Engineering,
More information