WSEAS Transactions on Communications QUICK LINKS Submit/Revise Paper Paper Format LOGIN Username Password Register Forgot Password Print ISSN: 1109-2742 E-ISSN: 2224-2864 Contents: 2013 | 2012 | 2011 | 2010 | 2009 | 2008 | Pre-2008 Submit a paper | Submission terms | Paper format Publication Ethics and Malpractice Statement Editorial Board: Editor-in-Chief Sandra Sendra Instituto de Inv. para la Gestión Integrada de Zonas Costeras (IGIC) Universidad Politécnica de Valencia SPAIN Associate Editors: Hime Aguiar ([email protected]) Hsin-Jang Shieh ([email protected]) Valentina E. Balas ([email protected]) Nayan Kumar ([email protected]) Mário Cesar do Espirito Santo Ramos ([email protected]) Karthikeyan Jayaraman ([email protected]) Satish Kumar Duraiswamy ([email protected]) Mohamed Zahran ([email protected]) Zengshi Chen ([email protected]) Gabriel Badescu ([email protected]) Saw Chin Tan ([email protected]) Eleazar Jimenez Serrano ([email protected]) Kevin Kam Fung Yuen ([email protected]) Giovanni Aiello ([email protected]) Eleonora Catsigeras ([email protected]) Josip Music ([email protected]) Panagiotis Gioannis ([email protected]) Constantin Popescu ([email protected]) Mueen Uddin Awan ([email protected]) Arvind Dhingra ([email protected]) Yang Zhang ([email protected]) Daniela Cristina Momete ([email protected]) Rajveer Mittal ([email protected]) BULLETIN BOARD Currently: The editorial board is accepting papers. Kindly note that your contributions must be at least 10 pages long and written in the exact WSEAS format. WSEAS Main Site NAUN Main Site Journal Contents Journal Topics International Scientific Journal http://wseas.org/wseas/cms.action?id=4021 1 dari 2 4/25/2013 8:29 PM
The editorial board is acceptingpapers. Kindly note that yourcontributions must be at least 10pages long and written in theexact WSEAS format.
WSEAS Main Site
NAUN Main Site
Journal Contents Journal Topics
International Scientific Journal http://wseas.org/wseas/cms.action?id=4021
1 dari 2 4/25/2013 8:29 PM
QUICK LINKS
Who We Are
Journals
Proceedings/Books
E-Library
Recent Conferences
Research Projects
Universities
Plenary Speakers
List of Reviewers
Become a Reviewer
Become a Member
Join Mail List
Your Feedback
Affiliates/Collaborators
Social Profile
CONFERENCES
JOURNALS
WSEAS TRANSACTIONS ON COMMUNICATIONS
Print ISSN: 1109-2742E-ISSN: 2224-2864
Volume 12, 2013
Issue 1, Volume 12, January 2013
Title of the Paper: Algorithmic Vertical Handoff Decision and Merit NetworkSelection Across Heterogeneous Wireless Networks
Authors: Sunisa Kunarak, Raungrong Suleesathira
Abstract: Next generation wireless networks must be able to coordinate servicesbetween heterogeneous networks through multi-mode mobile terminals. Suchheterogeneity poses a challenge to seamless handover since each access network hasdifferent operations. In this paper, the policies of multiple metrics for handoff topermit connectivity across UMTS and WLAN/WiMAX are designed. Moreover, how toselect an optimal target network is an important issue to balance against the networkcondition and user preference. The considered metrics for handoff initiation includethe predicted received signal strength (RSS) of neighbor networks and dwell time.The RSS is predicted by back propagation neural network which is beneficial toperform handoff early. Dwell time value depends on the user speed and movingpattern. The policy for triggering a handoff is that the RSS conditions are consistentlytrue during dwell time, so that unnecessary handoffs are avoidable. The predictiveRSS and current RSS conditions have different policies for real time and non-real timeservices in different networks. Policies in the merit function are presented to select anoptimal network. The weighting factors in the merit function are dynamic to neighbornetworks. To evaluate the algorithm, RSS prediction, network selection performanceand handoff decision performance are considered. The results indicate that theproposed vertical handoff decision algorithm and network selection outperforms theother two approaches in performing handoff earlier and reducing the number ofvertical handoffs, connection dropping, Grade of Service (GoS) while increasing theaverage utilization per call of WLAN/WiMAX networks.
Title of the Paper: Performance Analysis and PAPR Reduction of Coded OFDM(with RS-CC and Turbo coding) System using Modified SLM, PTS and DHTPre-coding in Fading Environments
Authors: Alok Joshi, Davinder S. Saini
Abstract: In wireless communication, parallel transmission of symbols using multi
BULLETIN BOARD
Important:
Starting with themulticonference in Chania,Crete Island, Greece inAugust, the registration feefor all our conferences willcover papers up to 10 pagesinstead of six that was theprevious limit.
April 2nd, 2013:
The paper submission deadlinefor the conferences in Brasov,Romania has been extended.
March 29th, 2013:
The conference program forMorioka City, Iwate, Japan isonline.
March 19th, 2013:
The 2013 conferences ofBudapest, Hungary are nowonline.
March 19th, 2013:
The paper submission deadlinefor the conferences in RhodesIsland, Greece has beenextended.
March 15th, 2013:
The paper submission deadlinefor the conferences inVouliagmeni, Athens, Greece hasbeen extended.
March 15th, 2013:
The conference program forKuala Lumpur, Malaysia isonline.
February 27th, 2013:
The 2013 conferences of Paris,France are now online.
February 20th, 2013:
The 2013 conferences of Nanjing,China are now online.
Main Page Indexes Upcoming Conferences with Expired Deadline Paper Submission Terms Propose a Special Session Contact Us
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
1 dari 9 4/25/2013 8:42 PM
carriers is used to achieve high efficiency in terms of throughput and bettertransmission quality. Orthogonal Frequency Division Multiplexing (OFDM) is one ofthe techniques for parallel transmission of information. In multipath environment theperformance of orthogonal frequency division multiplexing degrades which can beimproved by introducing some kind of channel coding. Coded OFDM (COFDM) is thenew candidate for application such as Digital audio Broadcast (DAB) and DigitalVideo Broadcast (DVB-T) due to its better performance in fading environments.However high peak to average power ratio (PAPR) is a major demerit of OFDMsystem, it leads to increased complexity and reduced efficiency of RF amplifier circuit.In this paper Modified Selective mapping (SLM), Partial Transmit sequence (PTS) andDiscrete Hartley Transform (DHT) precoding schemes are proposed for PAPRreduction, where SLM, PTS and DHT precoding schemes are used in conjunction withpost clipping and filtering processes. However clipping can degrade the BERperformance but the degradation in performance can be compensated by usingOFDM with channel coding; here we have used Reed Solomon (RS) codes along withconvolution codes (CC) used as serial concatenation and TURBO codes as parallelconcatenation code for channel coding purpose. The BER performances are simulatedfor Additive white Gaussian (AWGN), Rayleigh, Rician and Nakagami (m=3)channels and Complementary cumulative distribution functions (CCDF) curves aresimulated for modified as well as ordinary SLM, PTS and DHT precoding techniques.The COFDM system implemented here is as per IEEE 802.11a.
Title of the Paper: OVSF based Fair and Multiplexed Priority Calls AssignmentCDMA Networks
Authors: Vipin Balyan, Davinder S. Saini, Gunjan Gupta
Abstract: Code division multiple access (CDMA) networks uses orthogonal variablespreading factor (OVSF) codes to support different transmission rates for differentusers which suffers from code blocking limitation. Multiplexing in digitized world isused for data selection. In this paper, calls are multiplexed to share the capacity ofthe network fairly and with priority using OVSF codes for assignment. A multiplexer isused to provide each call their share of capacity. The different layers shares theircapacity with other layer in order to minimize code blocking. Simulation results provedominance and fairness of our design over other novel schemes.
Title of the Paper: Performance of Selected Diversity Techniques over the α-µFading Channels
Authors: Taimour Aldalgamouni, Amer M. Magableh, Ahmad Al-Hubaishi
Abstract: In this paper, approximate closed-form expressions for the bit error rate(BER) of M-ary quadrature amplitude modulation (MQAM) and M-ary phase shiftkeying (MPSK) are derived considering independent and identically distributed (i.i.d)α-µ fading channels with a maximal ratio combining (MRC) receiver. Moreover, otherclosed-form expressions are obtained for the symbol error rate (SER) of both MQAMand MPSK under the same channel conditions considering dual branch selectioncombining (SC) receiver. The derivations for MRC are based on the exponentialapproximation of the coherent BER formula for both MQAM and MPSK. For dualbranch SC, the derivations are based on very accurate SER approximation for bothMQAM and MPSK. The derived expressions can reduce to study the BER performanceover other fading channels such as; Rayleigh, Weibull, and Nakagami-m, as special
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
2 dari 9 4/25/2013 8:42 PM
cases. Numerical results are also provided for the derived expressions and they showclose match with Monte-Carlo simulations, especially for the case of dual branch SC.
Keywords: Maximum Ratio Combining (MRC), Selection Combining (SC), the -µ fadingchannel, generalized fading model, M-ary Quadrature Amplitude Modulation(MQAM), M-ary Phase Shift Keying (MPSK), Bit Error Rate (BER), and Symbol ErrorRate (SER).
Title of the Paper: Performance Comparison of Spreading Codes in LinearMulti-User Detectors for DS-CDMA System
Authors: J. Ravindrababu, E. V. Krishna Rao
Abstract: Direct Sequence Code Division Multiple Access (DS-CDMA) system is wellknown wireless technology. This system suffers from MAI (Multiple Access Interference)caused by Direct Sequence users. Multi-User Detection schemes were introduced todetect the users’ data in presence of MAI. Linear Multi-user Detectors andconventional Matched Filter (MF) are simulated using gold, PN and even kasamisequences as spreading codes in DS-CDMA system. In this paper odd kasamisequence is proposed. For this, odd kasami sequence of length L=2m which inclusiveof initial bit, The Bit Error Rate (BER) performance of MMSE Detector provides betterthan Decorrelating detector and conventional Matched filter. Comparative Studyshows that the proposed odd kasami sequence is better performed than gold, PN andeven kasami sequences in linear Multi-user Detectors and conventional Matched Filter(MF).
Keywords: Multi-user detection, Matched filter, Decorrelating detector, MMSE,DS-CDMA, PN sequence, gold sequence, even kasami sequence and odd kasamisequence
Title of the Paper: Three-Dimensional Model of Cylindrical Monopole PlasmaAntenna Driven by Surface Wave
Authors: Zili Chen, Anshi Zhu, Junwei Lv
Abstract: In the recent research on cylindrical monopole plasma antenna excited bysurface wave, several basal theoretical problems for the radiation of plasma antennaare investigated. Many meaningful results about plasmas antenna, e.g. the analysis ofphysical characteristics, numerical calculation methods, software simulation, diagnosisof parameters, etc. have already been obtained. As known that the plasma antennashave reconfigurable properties and many physical parameters of plasma antennaare governed by the applied electromagnetic field and actual coupling method, somodel research of plasma antenna is very necessarily in its further investigations andapplications. But the precise model of monopole plasma antenna according to itsthree-dimensional structure has not been proposed yet, the three-dimensional modelis proposed in the paper, three-dimensional distributions of electric and magneticfields around monopole plasma antenna are analyzed. The related formulas andequations of the model are derived by applying molecular dynamic theories andMaxwell-Boltzmann equations; in addition, numerical simulation methods are adoptedto verify validity of the proposed model.
Title of the Paper: Mobile Communication Safety on Road Transport
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
3 dari 9 4/25/2013 8:42 PM
Authors: H. Abdul Shabeer, R. S. D.Wahida Banu
Abstract: Telecommunication industry is the world's fastest growing industry with 5.3billion mobile subscribers (that's 77 percent of the world population) around theglobe. This significant rise in cellular phone use has served as the catalyst for majorroad accidents. They can be extremely distracting and cause careless andunavoidable accidents. Many people have been injured and even killed because ofwireless customers and their over-bearing cell phones. With the aim of preventingsuch types of accidents, we propose a highly efficient automatic electronic system forearly detection of incoming or outgoing call, an antenna located on the top of driverseat used for detecting when the driver uses mobile phone and an safety applicationnamed (Profile Changer) has developed using J2ME that will automatically loaded onthe drivers cell phone which helps in reducing the risk of accidents from occurring,while also ensuring the user need not worry about missing urgent calls. We haveextended our research by evaluating the outcome obtained with 2010 study from theUS National Safety Council and we have also shown the extent to which thisapplication helps to reduce economic losses in India.
Keywords: Mobile application to prevent accidents; cell phone while driving; IndianEconomic loss due to cell phone accidents, Driver detection, Distraction
Title of the Paper: Multi-Objective Cross-Layer Optimization with Pareto Methodfor Relay Selection in Multihop Wireless Ad hoc Networks
Authors: Nyoman Gunantara, Gamantyo Hendrantoro
Abstract: The focus of this paper is cross layer optimization of relay selection onmultihop wireless ad hoc networks. Cross-layer metrics that will be optimized arepower consumption, throughput, and load balancing in wireless ad hoc networks forthe outdoor and indoor configurations. Those three resources (performance indicators)are optimized using the multi objective optimization with Pareto method. The resultsobtained apply a dynamic ad hoc network model and optimization can be donesimultaneously to all three resources which are optimized based on the route or path.Several alternatives in the relay selection are shown in the following simulation. Theselection of the optimal relay can be based on one or a combination of the threeperformance indicators. The performance of the optimal relay selection in the field ofPOF (Pareto Optimal Front) is shown by the shortest Euclidean distance. The result ofoptimization for indoor and outdoor multihop ad hoc networks with threeperformance indicators is shown.
Keywords: Multi Objective Optimization, Cross Layer, Pareto Method, Relay Selection,Euclidean Distance, Multihop Wireless Ad hoc Networks, Performance Indicator,Outdoor and Indoor Configuration
Title of the Paper: An Agent-Assisted Fuzzy Cost Based Multicast QoS Routing inMANETs
Authors: G. Santhi, Alamelu Nachiappan
Abstract: Multicast routing and provision of QoS (Quality of Service) are challengingproblems due to the dynamic topology and limited resources in Mobile Ad hocNetworks (MANETs). This paper proposes an agent based QoS routing algorithm thatemploys fuzzy logic to select an optimal path by considering multiple independentQoS metrics such as buffer occupancy rate, remaining battery capacity of a mobilenode number of hops. In this method all the available resources of the path isconverted into a single metric fuzzy cost. This is based on multi-criterion objectivefuzzy measure. The path with the minimum fuzzy cost is used for the transmission.
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
4 dari 9 4/25/2013 8:42 PM
Gunantara
Rectangle
Here, the intelligent software agents move around the network and collectinformation of all mobile nodes. These agents can reduce the network delay andparticipate in network routing and route maintenance. The performance of theproposed Agent assisted Fuzzy cost based Multiobjective QoS Routing protocol(Agent_FCMQR) is compared with E-AOFR (Evolutionary Ad hoc On demand FuzzyRouting) and MQRFT (Multi metric QoS routing based on Fuzzy Theory) and thesimulation results show that the proposed protocol is superior over existing intelligencebased routing protocols.
Keywords: MANETs, multicast routing, Quality of Service, mobile agents, multi-objective, fuzzy cost
Title of the Paper: Implementation of Generalized Detector in MIMO RadarSystems
Authors: Vyacheslav Tuzlukov
Abstract: In this paper, we consider the problem of multiple-input multiple-output(MIMO) radars employing the generalized detector (GD) based on the generalizedapproach to signal processing in noise (GASP) and using the space-time coding toachieve a desired diversity. To that end, we derive a suitable GD structure afterbriefly outlining the model of the received target return signal. GD performance isexpressed in closed form as a function of the clutter statistical properties and of thespace-time code matrix. We investigate a particular case when GD requires a prioriknowledge of the clutter covariance, i.e., the decision statistics under the nullhypothesis of “a no” target is an ancillary statistic in the sense that it depends on theactual clutter covariance matrix but its probability density function (pdf) isfunctionally independent of such a matrix. Therefore, threshold setting is feasible withno a priori knowledge as to the clutter power spectrum. As to the detectionperformance, a general integral form of the probability of detection is provided,holding independent of the searched object fluctuation model. The formula is notanalytically manageable, nor does it appear to admit general approximateexpressions, which allow giving an insightful look in the MIMO radar systembehaviour. We thus restrict our attention to the case of Rayleigh-distributed targetattenuation (Swerling-1 model). To code construction we use an information-theoreticapproach and compare conditions for code optimality with ones for classical Chernoffbound. This approach offers a methodological framework for space-time coding inMIMO radar systems constructed based on GASP, as well as simple and intuitivebounds for performance prediction.
Keywords: Generalized detector, multiple-input multiple-output (MIMO), Rayleighfading, Chernoff bound, generalized approach to signal processing, Swerling-1model
Title of the Paper: A Modified PTS Combined with Interleaving and Pulse ShapingMethod Based on PAPR Reduction for STBC MIMO-OFDM System
Authors: P. Mukunthan, P. Dananjayan
Abstract: Multiple input multiple output orthogonal frequency division multiplexing(MIMO-OFDM) system have been proposed in the recent past for providing highdata-rate services over wireless channels. When combined with space time coding itprovides the advantages of space-time coding and OFDM, resulting in a spectrallyefficient wideband communication system. However, MIMO-OFDM system suffer withthe problem of inherent high peak-to-average power ratio (PAPR) due to theintersymbol interference between the subcarriers. To overcome this problem, thepartial transmit sequence (PTS) based on PAPR reduction by optimally combiningsignal subblocks and the phase rotation factors is considered. As the number ofsubblocks and rotation factors increases, PAPR reduction improves. The number ofcalculation increases as the number of subblocks increases, such that complexityincreases exponentially and the process delay occur simultaneously. In this paper,
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
5 dari 9 4/25/2013 8:42 PM
PAPR reduction schemes based on a modified PTS combined with interleaving andpulse shaping method for STBC MIMO-OFDM system has been presented. The paperanalyses the influence of the number of the detected peaks on PAPR reductionperformance and on complexity, and then obtain the optimal parameter to achievebetter PAPR reduction performance and lower complexity. Simulation results show thatthe proposed modified PTS with interleaving and the pulse shaping method canobviously improve PAPR performance in the MIMO-OFDM system.
Title of the Paper: Performance Analysis, Improvement and Complexity Reductionin Multi Stage Multi-User Detector with Parallel Interference Cancellation forDS-CDMA System Using Odd Kasami Sequence
Authors: J. Ravindrababu, E. V. Krishna Rao
Abstract: Direct Sequence Code Division Multiple Access (DS-CDMA) system is wellknown wireless technology. This system suffers from MAI (Multiple Access Interference)caused by Direct Sequence users. Multi-User Detection schemes were introduced todetect the users’ data in presence of MAI. In Multi stage Partial parallel interferencecancellation (MP-PIC) method complexity is more than multi stage conventional PIC(MC-PIC), but performance is better than MC- PIC. In This paper we proposed multistage subtractive PIC (MS-PIC). In this method the complexity is less than MP-PIC andperformance is slightly less than MP-PIC. Now we proposed one more method that isthe combination of partial and subtracting parallel interference cancellation (PS-PIC)in multi stage. This method gives to achieve performance improvement andcomplexity reduction compared to conventional multistage PIC detector.
Keywords: Multi-user detection, MAI, Matched filter, , DS-CDMA, PIC.odd kasamisequence
Title of the Paper: Reconfigurable Characteristics of the Monopole PlasmaAntenna and Its Array Driven by Surface Wave
Authors: Anshi Zhu, Zili Chen, Junwei Lv
Abstract: Reconfigurable characteristics of monopole plasma antenna areinvestigated in the paper, related analysis and experiments on the reconfigurablecharacteristics of the plasma antenna e.g., working frequency, radiation pattern arecompleted and many experimental results are obtained. The research results showthat the reconfigurable characteristics of monopole plasma antenna can be realizedand optimized under certain external excited conditions. The radiation parametersthe plasma antenna array also can be reconfigured through changing variableparameters of the plasma elements, the related analysis and simulations arepresented.
Title of the Paper: A Systematic Design of High-Rate Full-Diversity Space-Frequency Codes for Multiuser MIMO-OFDM System
Authors: R. Shelim, M. A. Matin, A. U. Alam
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
6 dari 9 4/25/2013 8:42 PM
Abstract: The authors have proposed a new space-frequency (SF) code forMIMO-OFDM system in their paper. The data streams of all the users are sentsimultaneously through all the OFDM sub-channels. The proposed SF code canachieve high symbol rate ( rate ) with full diversity ( ) where denotes the number oftransmit antenna for each user, denotes number of receive antenna at the receiverand denotes the number of independent channel taps. The threaded algebraiclayering concept is used to construct this SF code which combines the space-frequencylayering theory with algebraic component codes. The component code is consideredto be an algebraic number theoretic constellation. Each component code is assignedto a “thread” and interleaved over space and frequency. Diophantine approximationtheory is then used to make the threads transparent to each other. In addition,another approximation is used so that the users become transparent to each other.Our SF code does not require zero-padding, which always ensures high symbol rate.It is proved through simulation that the proposed coding scheme achieves highercoding and diversity gain over recently proposed space-frequency code.
Abstract: This paper aims at analysis efficiency in estimating the performance of treeconnected servers. We use a queuing model to represent their equivalentperformance and service quality. The queue types of the connection servers can beclassified as serial, parallel and tree connections. We design an algorithm to simplifythe equivalent serial-parallel queues. According to the equivalent queues we computethe system response time of tree connected servers. We use a network simulation andan analytical software tool to represent the equivalent performance of the queue.Our simulation uses various different service rates and arrival rates of the queuemodels and finds the system response time. We also measure the average systemresponse time in comparison with the simulation result to find out the service rates ofthe actual servers and evaluate the accuracy of the algorithm. We will find that theerror margin of measurement, simulation and computing ranges from 1.37%-19.27%.
Keywords: Serial-parallel Network, Web Servers, Service Rate, Tree ConnectedServers, System Response Time, Equivalent Queuing Network
Title of the Paper: A New Finite Word-length Optimization Method Design forLDPC Decoder
Authors: Jinlei Chen, Yan Zhang, Xu Wang
Abstract: A new word-length optimization method based on Monte Carlo simulation isproposed. The word-length of the check node extrinsic message is also furtheroptimized in this paper. In the proposed optimization method, and in the process ofoptimizing the word-length of the channel data, the statistical distribution results ofvariable node’s posterior probability data and check node’s extrinsic message arealso obtained. The optimized word-length of variable node’s posterior probabilitydata and check node’s extrinsic message is concluded by the statistical distributionresult and the BER (Bit Error Rate) curves. Compared to the pure Monte Carlosimulation, the proposed method could reduce the amount of simulation work by morethan 50%, and have the same word-length optimization results.
Keywords: LDPC decoder, word-length optimization, Monte Carlo simulation, min-sum
Issue 5, Volume 12, May 2013
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
7 dari 9 4/25/2013 8:42 PM
Title of the Paper: Error Correction and Equilibrium investigation in RandomAccess MAC Protocols for Wireless Networks
Abstract: This research focuses on network performance, and how to solve theproblem of low throughput in the Aloha medium access control (MAC) protocol and itsderivatives. For this purpose, we propose two complementary solutions. The firstconsists of the integration of the erasure coding scheme in this protocol to recovercollided packets and to reduce the rate of collision between transmitted packets.Here, since each node sends N coded packets instead of the k original packets, wehave (N-k) redundant packets. The introduction of redundancy and subsequentlystructuring it in an exploitable manner, allows serious errors injected by the channel tobe corrected. However, if each node attempts to achieve its best output withoutregard for the other nodes’ actions, this could affect overall system throughput. Toanalyze such conflicting situations where the action of one node has an impact on theother nodes’ actions, we add a complementary solution, which is based on the gametheory technique of acquiring network equilibrium. This makes the network strongerand able to resist many collisions.
Keywords: Slotted-Aloha, CSMA, Erasure Coding, Game theory
Title of the Paper: Design of Flexible Layer-3 Routing Protocol with Variable-Length Address Information and Its Implementation
Authors: Yasuhiro Sato, Yusuke Toji, Shingo Ata, Ikuo Oka
Abstract: In next-generation network architectures, the number of nodes andequipment connected to information networks increase more than ever. Due to theexplosive increase of network equipment, an information retrieval technique to accessinformation surely and efficiently will be strongly required. For this, one of the currentapproaches is intelligent routing, such as DHT, which is implemented on upper layersthan IP layer. However, the inefficiency in processing packets and the mutualinterference between layers are caused, because similar functions are implementedon different layers as different routing protocols. In this paper, we propose a newlayer-3 routing protocol that can achieve flexible information retrieval implementedon overlay networks. For this purpose, we design a new routing protocol that can usevariable-length address information, such as keyword or device name, as its addressinformation. Moreover, we consider the feasibility of our routing protocol byimplementing it to GNU Zebra as an extension of BGP.
Title of the Paper: Performance of Concatenated Optimized Irregular LDPC Codewith Alamouti Coded MIMO-OFDM Systems
Authors: Bhasker Gupta, Davinder S. Saini
Abstract: Multiple input multiple output (MIMO) communication systems along withorthogonal frequency division multiplexing (OFDM) have a great potential for future4G broadband wireless communications. Recently, low density parity check codes(LDPC) achieves good error correcting performance and capacity near Shannon’slimit. In this paper, we considered the performance analysis of serially concatenatedregular and irregular LDPC codes with Alamouti space time block coded (STBC) andspace frequency block coded (SFBC) MIMO-OFDM systems for high data ratewireless transmission. Currently, most of the research related to this area is
WSEAS - World Scientific and Engineering Academy and Society http://wseas.org/wseas/cms.action?id=5344
8 dari 9 4/25/2013 8:42 PM
concentrated on the impact of increase in code rate and diversity of the system butnot on increase in coding gain. In this paper, we analyzed the impact of increasingcoding gain. Performance analysis and design optimization is carried out using densityevolution (DE) tool with mixture of Gaussian approximations over Rayleighindependent and identically distributed (i.i.d) channels
Keywords: MIMO-OFDM, Alamouti codes, Density Evolution (DE), LDPC codes,Maximum a Posteriori (MAP), Maximum Likelihood (ML) detection
Title of the Paper: Performance Analysis of Channel Coding in SatelliteCommunication Based on VSAT Network and MC-CDMA Scheme
Authors: Mohammed El Jourmi, Hassan El Ghazi, Abdellatif Bennis, HassanOuahmane
Abstract: Satellites are an essential part of our daily life, and they have a very largeusage ranging from Search and Rescue Operations to Environmental Monitoring. Thewidest use of satellites is, however, in communication systems. Satellites can cover vastareas on the world; therefore, they are the nodes where all links pass through in acommunications network. Many users can access such a network simultaneously whilethey are widely separated geographically. The purpose of this paper is to model andanalyze a geostationary satellite communication system with VSATs networks in theuplink case, using Multicarrier CDMA system (MC-CDMA is a combination ofmulticarrier modulation scheme and CDMA concepts) and channel coding mechanisms“Turbo code and Convolutional code”. The envisaged system is examined in Ku bandand over AWGN channel. The simulation results are obtained for each different case.The performance of the system is given in terms of Bit Error Rate (BER) and Signal toNoise Ratio (SNR). In this study the proposed system coded with Turbo code canachieve better error rate performance compared to coded VSAT MC-CDMA systemwith convolutional code.
Abstract: - The focus of this paper is cross layer optimization of relay selection on multihop wireless ad hoc networks. Cross-layer metrics that will be optimized are power consumption, throughput, and load balancing in wireless ad hoc networks for the outdoor and indoor configurations. Those three resources (performance indicators) are optimized using the multi objective optimization with Pareto method. The results obtained apply a dynamic ad hoc network model and optimization can be done simultaneously to all three resources which are optimized based on the route or path. Several alternatives in the relay selection are shown in the following simulation. The selection of the optimal relay can be based on one or a combination of the three performance indicators. The performance of the optimal relay selection in the field of POF (Pareto Optimal Front) is shown by the shortest Euclidean distance. The result of optimization for indoor and outdoor multihop ad hoc networks with three performance indicators is shown. Key-Words: - Multi Objective Optimization, Cross Layer, Pareto Method, Relay Selection, Euclidean Distance, Multihop Wireless Ad hoc Networks, Performance Indicator, Outdoor and Indoor Configuration 1 Introduction An ad hoc network is a set of nodes that communicate dynamically and do not have a fixed infrastructure. Each individual node can act as a source, relay, and destination. Those nodes have limited transmission range and battery capacity [1]. Thus, nodes communicating in ad hoc networks might require a relay or shall cooperate with another node which acts as relay.
Relay has been tested to be applied to WLAN-based access point networks where a node communicates with another through a third node in its path. The result is an increase in cell capacity, energy efficiency, and a reduction in emissions of electromagnetic fields [2]. In [3], Li examines the relay selection on multihop of ad hoc networks based on signal to interference plus noise ratio (SINR). This study has a low complexity but is very helpful in analyzing performance on multihop communication. A node’s SINR is determined according to the previous node along the path to optimize the capacity of the channel. Bletsas et al in [4] proposes a distributed relay selection scheme where a user selects the best path of source-relay-destination out of many relays that may be based on
the biggest channel gain. In [5], Huang et al examines relay selection based on the two auction mechanisms, the SNR auction and power auction, for the allocation of distributed resources. The expected outcome of the auction process is in the form of Nash Equilibrium. The results obtained are resources in the form of greater throughput in SNR auction than in the power auction. In the study reported in [1-5], the relay selection is based only on resources in the physical layer. Resources that lie outside the physical layer (higher layer) can also affect the relay selection. In other words, an exchange of resources from the physical layer and higher layer for relay selection is desired. This encourages the development of combined optimization of resources in the physical and higher layers, which is called cross-layer optimization.
Cross-layer optimization for relay selection has been performed by many researchers. Here we will clarify some researches which are related to and support this research. Shi et al in [6] examines ways to increase throughput in the communication pair of source and destination in an ultra wide band (UWB) based ad hoc networks. The increase of the throughput is based on cross-layer approach namely
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 85 Issue 3, Volume 12, March 2013
scheduling and power control in the data link layer and routing in the networks layer. Throughput is obtained from the optimization result using the reformulation linearization technique (RLT). In [7], Le and Hossain explains cross-layer optimization in cooperative communication system for the physical layer and networks in form of joint routing, relay selection, and power allocation to minimize power consumption in the networks. It is subsequently expanded with the addition of congestion control to optimize the traffic and look for a power tradeoff (compromise) in the system. The method used is convex optimization with the Lagrange optimization technique. In [8], Chen et al performs cross-layer based optimization in the cooperative communication system of the relay selection. The resources which are optimized are energy efficiency and load balancing. Energy efficiency is obtained based on the duration of time while load balancing is applied to each node so that each node uses the same energy. For a stationary node which acts as relay, it turns out that energy efficiency and load balancing can not be achieved simultaneously. In order to solve this problem, multi-state cooperative is used. The energy efficiency of the node is performed to optimize the throughput and outage probability. Optimization is performed with convex optimization in Kurash-Kuhn-Tucker (KKT) condition. Ding et al in [9], discusses the cross-layer optimization in the form of joint routing, relay selection, and dynamic allocation of frequency spectrum to maximize throughput. The research was conducted for ad hoc networks of cognitive radio and optimization was performed with convex optimization. In the study reported in [6-9], the relay selection is performed by cross-layer optimization to improve resources performance. Since cross-layer optimization of relay selection involves a compromise of multiple objectives, some of which are contradicting each other, it is appropriate to adopt multi-objective optimization (MOO) approach [10].
In [11], Karkkainen et al examines mobile terminal which will be able to communicate with service providers using multiple networks connections. Each network connection has a various transmission speed and values. In selecting a networks connection, the problems, which are time and cost, are formulated into MOO. Both problems are solved using the scalarization method. Settlements used are the weighting method, neutral compromise solution, and the achievement of scalarizing function. Baynast et al in [12], examines cross-layer optimization for radio multicarrier system in the automatic repeat request (ARQ) based
cognitive radio networks. There are four optimized problems namely packet error rate (PER), power consumption, throughput, and delay. The four issues are formulated into a scalar form. Furthermore, the settlement is performed using weighted sum approach and genetic algorithm. Elmusrati et al in [10], discusses radio resource scheduling (RRS) in the cellular communication system. RRS controls the radio resources, which are transmit power and data rate, to solve the problems by minimizing total transmit power, minimizing the outage, and maximizing throughput. These three problems are opposite, the two performance indicators should be minimized while the other one is maximized. Optimization is performed by merging the three problems into MOO. These three problems are formulated into scalarizing function and solved using weighted metric method. From studies in [10-12], MOO is solved using scalarization. In MOO with scalarization, the objectives can not be optimized separately because their solutions are dependent on one another. Later, in order to overcome this shortcoming, our study proceeds using MOO with the Pareto method.
Research using the Pareto method in solving the MOO problems in the field of wireless communication is still new. Initial studies initiated by Runser et al in [13], examines the application of the Pareto method in the solving of MOO problems in the wireless ad hoc networks. Three optimization problems are robustness, energy consumption, and delay. Initial results obtained are tradeoff characteristic of robustness, energy consumption, and delay for 2-hop ad hoc networks. This preliminary result becomes a motivation for the research reported in this paper, which is also to answer the lack of the research following [8] for wireless networks with relay.
In this study, our main contribution is first, optimization for dynamic ad hoc networks model that can be performed simultaneously for the optimized resources based on the route / path. Second, the optimization results are expressed in the Pareto optimal front (POF) in three dimensions and provide optimal performance of Pareto optimal solutions (POS). Third, it shows the optimization results for multihops ad hoc networks with indoor and outdoor scenarios with three performance indicators.
The rest of this paper is organized as follows. Section 2 provides an overview of ad hoc networks, radio propagation, and multiple problems optimization. Section 3 describes the model configuration, simulation parameter, and analysis of
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 86 Issue 3, Volume 12, March 2013
simulation results. Finally, the conclusions are presented in Section 4. 2 Problem Formulation 2.1 Wireless ad hoc networks Wireless ad hoc networks can be described in a graph G = (V, L), where V = {1, 2, ... , N } is the set of nodes and L = {(1,2), (1.3), ... , ( N-1, N )} is the set of links/hops. Ad hoc multihops networks contain pairs of nodes in communication involving other nodes as relays. A set of a number of links that form a multihop is called a path. If the number of total nodes (including source and destination) is N, then there are (N-2) 2-hop solutions, (N-2) (N-3) 3-hop solutions, (N-2) (N-3) (N-4) 4-hop solutions, and so on for the source and destination pair. In this study, the hop is limited to only three hops. Then every 3-hop solution is a path that is source-relay-relay-destination.
There are four methods of routing in ad hoc networks namely unicast routing, multicast routing, broadcast routing, and geocast routing [14]. In this study, broadcast routing is used where source transmits information to all nodes that each might serve as a relay so that the information arrives at the destination. Broadcast routing is chosen so that the transmitted data can be received by all the nodes next to them simultaneously so as to save time in the transmission.
2.2 Radio Propagation 2.2.1 Outdoor It is assumed that each transmitter node can set the transmit power based on the feedback from the opposite node. Assuming that the transmitter and receiver antenna gain, and , are the same, and that the minimum power received through the wireless channel specified, then the minimal transmit power consumption required is:
10 (1)
with denoting a multiplier constant, representing the path loss exponent, and shadowing loss (dB) which is normally distributed with standard deviation . In this study, the multiplier constant is valued unity and every link / hop has a different shadowing value.
2.2.2 Indoor For indoor scenario, the nodes in the ad hoc networks are inside a room. The rooms are separated by walls that might attenuate signals. This causes transmission coefficient [15]. Power consumption of a node transmitting to other nodes in different room can be determined through equation (1) by enclosing the influence of the transmission coefficient into the following:
10 1
∏ Γ (2)
with Γ and being the transmission coefficient of the wall and the number of walls, respectively. 2.3 Ad hoc Network Performance Indicators 2.3.1 Power Consumption Power consumption in the path is the overall power required in transmitting data from source to destination through multiple relays in each path. For ad hoc networks with three hops, every path is composed of = 3 links. Power consumption in a path number for the outdoor and indoor conditions can be determined through the following equation :
(3)
While the optimal power consumption is the power consumption which has the smallest value of all path. The equation is as follows :
min , , … , (4)
2.3.2 Throughput Throughput in each link is the number of bits successfully transmitted in the link every second. For simplicity, the amount of throughput in this study can be represented by the value of channel capacity. Under a perfect condition, the value of the throughput approaches the channel capacity. Throughput value will be maximum if the reception power is also maximum for the constant bandwidth and noise power. The capacity can be calculated through the following equation [16] :
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 87 Issue 3, Volume 12, March 2013
1 (5)
where is the channel bandwidth and is the noise power. In this study, the noise that is affecting is the thermal noise and the noise power magnitude in each link/hop is considered constant.
The throughput for outdoor and indoor conditions depends on the magnitude of the outdoor and indoor maximum reception power. For ad hoc networks with three hops, the throughput in the path
can be determined through the following equation:
min , , (6)
While the optimal throughput in an ad hoc
networks in the path -th is the maximum throughput of all paths which can be determined through the following equation:
max , , … , (7)
2.3.3 Load Balancing Load balancing, commonly referred to as fairness, is inversely indicated by the variance of some resources or performances [17]. In the wireless ad hoc networks, load balancing is very important because some nodes may have a better chance as a relay. If a node is used as a relay, the load of the node becomes:
(8)
where B and B respectively are the traffic load of itself and the traffic load that leads to the i node.
After the load of each node is determined, the load balancing of each path can be reviewed based on the variance of the load of all nodes in the area with the following equation [17]:
1 1 (9)
From variances that occur in every path selection, the optimal path can be determined through the following equation:
min , , … , (10)
2.4 Multi Objective Optimization Optimization is the process of finding the best solution for optimization problems. For opposite problems, where the power consumption problem requires minimization, the load balancing problem needs minimization of load variance, while the throughput problem calls for maximization, the Pareto method can be used in finding the best solution. Mathematically the three problems can be written as follows [18]: Min Max Min (11) Subject to : where is the threshold reception power.
Optimization with the Pareto method maintains the solution in the Pareto optimal front (POF) for the two problems separately during optimization. In POF, there is a dominance concept to differentiate dominated (inferior) and non-dominated solution (non-inferior). For the optimization of two problems, two non-dominated solutions can be described in plane POF (two dimensions). As for the optimization of three problems, the non-dominated solutions can be described in three-dimensional field POF [19]. POF of two problems, minimum and maximum, can be seen in Fig. 1 [20].
In determining the optimal value of a POF, the Utopia point should be determined first. The utopia point is the point in the objective space determined by the optimal value of each problem independently. After the Utopia point is determined, the optimal value can be determined by finding the shortest Euclidian distance [21].
The shortest Euclidean distance can be determined by the following equation [22]:
min
(12)
where , is the coordinate of the Utopia points, , is the coordinate of POF points, and , is the coordinate of the normalization points on the problem areas.
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 88 Issue 3, Volume 12, March 2013
Z1
***
**
* *Non dominatedsolution
Dominatedsolution
POF
*
Z2
Fig 1. Pareto Optimal Front (POF) for Two Problems
Fig 2. Outdoor Configuration
is determined based on the minimum value of . Whereas is determined based on the maximum value of . 3 Numerical Results 3.1 Model Configuration We consider ad hoc networks configurations working outdoors and indoors. Model for the outdoor condition can be seen in Fig 2. While the model for the indoor condition can be seen in Fig 3. In Fig 2, all nodes are in an open space of 40 m x 40 m. Meanwhile, in Fig 3, it is shown that the building area of 40 mx 40 m is divided into 16 rooms. Each room in the building is
Fig 3. Indoor Configuration
Fig 4. OFDMA Method
bounded by walls. Both configuration models have 32 nodes in random position.Node 1 serves as the source in our simulation, with node 32 as the destination, and the other nodes act as potential relays to form a three-hop ad hoc networks.
The protocol adopted by the system model can be described as follows: - Source can identify the position of the destination.
The process of identifying can be performed in a way that each node can detect other nodes through one hop and transmits the information to all nodes next to it in one hop [23].
- To avoid the occurrence of interference and collision between the nodes, the OFDMA (orthogonal frequency division multiple access) method is used in accordance with reference [24]. Each path uses different sub-carrier. While for each link in a path, different time slot is used. More details can be seen in Fig 4. In Fig 4, the frequency / sub-carrier and time slot division for both path 1-2-3 and 4-5-6-7 is shown.
0 5 10 15 20 25 30 35 400
5
10
15
20
25
30
35
40
node position (m)
node
pos
ition
(m)
1
2
3 4
5
6 7
8
9 10
11 12
13
14
15
16
17
18 19
20
21 22
23 24
25
26
27
28 29
30 31
32
0 5 10 15 20 25 30 35 400
5
10
15
20
25
30
35
40
node position (m)
node
pos
ition
(m)
1
2
3 4
5
6 7
8
9 10
11 12
13
14
15
16
17
18 19
20
21 22
23 24
25
26
27
28 29
30 31
32
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 89 Issue 3, Volume 12, March 2013
Table 1 Parameters of Simulation
Parameter : Value
Outdoor path loss exponent , : 4 Indoor path loss exponent, : 2 Standard deviation of shadowing, : 8 dB Wall transmission coefficient, Γ : 0,3 Threshold receive power, : - 50 dBm Bandwidth, : 20 MHz Noise, : -101 dBm
Fig 5. POF of Power Consumption and Throughput for Outdoor
Fig 6. POF of Power Consumption, Throughput, and Load Balancing for Outdoor
-30 -28 -26 -24 -22 -20 -18 -16 -14 -123.2
3.4
3.6
3.8
4
4.2
4.4
4.6x 108
Power Consumption (dBW)
Thro
ughp
ut (b
ps)
Path 1-10-22-32
-30-25
-20-15
-10
3
3.5
4
4.5
x 108
25
30
35
40
45
50
55
Power Consumption (dBW)Throughput (bps)
Load
Bal
anci
ng
Path 1-10-22-32
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 90 Issue 3, Volume 12, March 2013
Parameter values used in this simulation are
taken based on the application of WLAN in wireless ad hoc networks shown in Table 1.
To evaluate the load balancing in this simulation, it is assumed that in addition to source that transmits the data to the destination, there are five nodes that transmit the data simultaneously to their respective destination nodes. As a result, there are multiple nodes that have a better chance as a relay. Those five nodes groups are assumed to be the path 4-12-29-32, 7-11-19-25, 10-19-22-23, 16-12-14-2 and 25-20-12-6. It is assumed that the sources, node 4, node 7, node 10, node 16, node 25 respectively can transmit the data at a rate of 5 Mbps, 3 Mbps, 8 Mbps, 7 Mbps, 2 Mbps and 11 Mbps respectively. While other nodes might be having a load of 2 Mbps, 7 Mbps, 12 Mbps and 17 Mbps. The loads of the nodes are scattered randomly.
3.2 Outdoor Based on the power consumption, the optimal value is a path that has the minimum power consumption. Accordingly, path (1-11-22-32) with the normalized power consumption of -29.1821 dBW is selected.
As for the throughput, a path that has the maximum throughput is selected. There are three paths that have maximum throughput value. Those paths are (1-10-21-32), (1-10-22-32) and (1-10-27-32), each with throughput value of 443.21 Mbps.
Determining the optimal relay based on a single problem that is based on power consumption or throughput is relatively simple. If more than one problem and many searches for solution space are performed, determining the solution becomes difficult. Thus, Pareto optimization technique is required.
Optimization with Pareto methods leads to a trade-off between power consumption and throughput. Compromise for both problems can be seen in Fig 5, based on which the calculation for Euclidean distance is performed. The result is the shortest Euclidean distance of 0.0020 for path (1-10-22-32) which is marked by a star in Fig. 5, indicating that the optimal relay selected corresponds to path (1-10-22-32).
The existence of the load balancing value for outdoor condition causes the POF may be formed in three dimensions. Fig 6 shows that points marked by circles and star have the smallest value of load balancing of 27.7122. By taking these three
resources into account, the selected optimal relay corresponds to path (1-10-22-32) because it has the shortest Euclidean distance of 0.0223 which is indicated by a star in Fig. 6. 3.3 Indoor Based only on the power consumption, the optimal value is the path that has minimum power consumption. Accordingly, the path (1-12-22-32) with power consumption of -33.6347 dBW is selected.
As for the throughput value, a path that has a maximum throughput value is selected. The selected paths are (1-12-21-32) and (1-12-22-32) with a throughput of 674.98 Mbps.
Optimization with Pareto method causes a compromise between power consumption and throughput, as can be seen in Fig 7.
Based on Fig 7, the calculation for the Euclidean distance is performed. The result is the shortest Euclidean distance of 0 for path (1-12-22-32) which is symbolized by a star. Thus, the selected optimal relay is path (1-12-22-32).
The incorporation of load balancing into the optimization problem for indoor condition requires the POF to be formed in three dimensions. Fig 8 shows that points marked by circles and star have the smallest load balancing value of 27.7122. By taking these three resources into account altogether, the selected optimal relay is path (1-6-22-32) because it has the shortest Euclidean distance of 0.0804 which is marked by a star. 3.4 Discussion Fig 5 shows that the POF results for outdoor conditions has scattered compromise values, while for indoor conditions Fig.7 shows a tendency of clustered compromise value to converge toward the Utopia point. This is due to the presence of several relays for indoor conditions which have similar power consumption value but have different throughput values. One possible explanation is that nodes in one room appear to experience similar total wall attenuation with respect to each of those in other rooms due to the same number of intervening walls, and further, the total wall attenuation experienced by these nodes differs from that experienced by nodes in other rooms.
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 91 Issue 3, Volume 12, March 2013
Fig 7. POF of Power Consumption and Throughput for Indoor
Fig 8. POF of Power Consumption, Throughput, and Load Balancing for Indoor
The optimal relay selection in two dimensional POF (of Fig 5 and Fig 7) for the two conditions used to form a multihop networks is the sequence of relays which approaches a straight line between the source and destination, and the distance of which between the source-relay-destination is approximately equal. With the presence of load
balancing in the optimization problem (see Fig 6 and Fig 8), the optimal relay selection might change so it does not form a straight line because the nodes positioned at a straight line are more often used as a relay so that the load balancing variance is high.
Based on Fig 5 and Fig 7, the power consumption for indoor condition is greater than for
-40 -30 -20 -10 0 10 203
3.5
4
4.5
5
5.5
6
6.5
7x 108
Power Consumption (dBW)
Thro
ughp
ut (b
ps)
Path 1-12-22-32
-40
-20
0
20
34
5
67
x 108
25
30
35
40
45
50
55
Power Consumption (dBW)Throughput (bps)
Load
Bal
anci
ng
Path 1-6-22-32
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 92 Issue 3, Volume 12, March 2013
outdoor. There are even some indoor paths which have more than 0 dBW. For example, the power consumption of 18.6 dBW makes path 1-31-3-32 not a realistic choice because the ad hoc terminal has a little battery power and hence the relay selection is extreme/not appropriate. This might happen due to the walls that reduce the power of the signal penetrating through them.
But based on Fig 5 and Fig 7, in optimal condition, the power consumption for outdoor condition is greater than for the indoor condition, while the throughput on the conditions outside the building is smaller compared to the conditions in the building. This is because the path loss exponent for outdoor is assumed to be 4, greater than that assumed for indoor which is 2. In load balancing, if the load of the nodes that will act as a relay has less variations, the number of alternative paths will be greater, and vice versa, if the variations are more, the alternative paths will be fewer. 4 Conclusion This paper has described the application of MOO technique with Pareto method for three performance indicators namely power consumption, throughput, and load balancing. The performance of the optimal relay selection in the field of POF for outdoor and indoor conditions is indicated by the shortest Euclidean distance. From the analysis of the simulation results, three conclusions can be made . First, it is found that the result of two-dimensional POF for outdoor condition has scattered compromise values while for indoor condition, the compromise values tend to converge toward the Utopia point. This is caused by the presence of some relays having similar power consumption value but have different throughput values. Secondly, for outdoor condition, all the nodes can act as a relay pairs, while for the indoor condition, the nodes must be accurately selected as relay pairs as there are some node pairs which do not qualify as relay. Third, the result of the three-dimensional POF shows that for outdoor condition, it has a scattered compromise values while for the indoor condition, it looks like clusters due to the same number of attenuating walls experienced by links to nodes in the same room. Acknowledgment The graduate study and research work of N. Gunantara has been supported by Postgraduate
Scholarship from Directorate General of Higher Educational (BPPS), Ministry of National Education, Republic of Indonesia. References: [1] D. D. Perkins, H. D. Hughes, and C. B. Owen,
“Factors Affecting the Performance of Ad Hoc Networks,” Proceedings of the IEEE International Conference on Communications (ICC), pp.2048-2052, 2002.
[2] M. Kubisch, S. Mengesha, D. Hollos, H. Karl, and A. Wolisz, “Applying ad-hoc relaying to improve capacity, energy efficiency, and immission in infrastructure-based WLANs,” Proc. of Kommunikation in Verteilten Systemen, Leipzig, Germany, 2003.
[3] X. Edward Li, “Hop Optimization and Relay Node Selection in Multi-Hop Wireless Ad-hoc Networks,” LNCS Social Informatics and Telecommunications Engineering, Vol. 2, pp 161-174, 2009.
[4] A. Bletsas, A. Lippman, and D. P. Reed, “A Simple Distributed Method for Relay Selection in Cooperative Diversity Wireless Networks, based on Reciprocity and Channel Measurements,” Proceedings of the IEEE Vehicular Technology Conference Spring, Stockholm, Sweden, 2005
[5] J. Huang, Z. Han, M. Chiang, and H. V. Poor, “Auction-Based Resource Allocation for Cooperative Communications,” IEEE Journal on Selected Areas in Comm. vol. 26, no. 7, 2008.
[6] Y.Shi, Y.T. Hou, H. D. Sherali, and S. Kompella, “Cross Layer Optimization for UWB-Based Ad hoc Networks,” Military Communications Conference (MILCOM), pp. 1-7, 2006.
[7] Le, L., and Hossain, E., (2008), Cross layer optimization frameworks for multihop wireless network using cooperative diversity, IEEE Trans. On Wireless Communication, vol. 7, no. 7.
[8] W. Chen, L. Dai, K. B. Letaief, and Z. Cao, “A Unified Cross Layer Framework for Resource Allocation in Cooperative Networks,” IEEE Transc. on Wireless Communications, vol. 7, no. 8, 2008.
[9] L. Ding, T. Melodia, S. N. Batalama, and J. D. Matyjasy, “Distributed Routing, Relay Selection, and Spectrum Allocation in Cognitive and Cooperative Ad Hoc Networks,” Proceedings of the Seventh Annual IEEE Communications Society Conference on
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 93 Issue 3, Volume 12, March 2013
Sensor, Mesh and Ad Hoc Communications and Networks, Boston, 2010.
[10] M. Elmusrati, H. El-Sallabi,and H. Koivo, “Applications of Multi-Objective Optimization Techniques in Radio Resource Scheduling of Cellular Communication Systems,” IEEE Transc. on Wireless Communication, vol. 7, no. 1, 2008.
[11] A. S. Karkkainen, K. Miettinen, and J. Vuori, “Best Compromise Solution for a New Multiobjective Scheduling Problem,” Elsevier : Computers & Operations Research vol. 33, pp 2353–2368, 2006.
[12] A. de Baynast, P. Mahonen, and M. Petrova, “ARQ-Based Cross Layer Optimization for Wireless Multicarrier Transmission on Cognitive Radio Networks,” Elsevier : Computer Networks vol. 52, pp 778–794, 2008.
[13] K. J. Runser, C. Comaniciu, and J. M. Gorcey, “A Multiobjective Optimization Framework for Routing in Wireless Ad Hoc Networks,”IEEE International Symposium on Conference Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt), 2010.
[14] R. Ranjan Roy, “Handbook of Mobile Ad hoc Networks for Mobility Models,” Springer, London, 2011.
[15] W. Honcharenko, H. L. Bertoni, , and J. Dailing, “Mechanisms governing propagation between different floors in buildings,” IEEE Transc. On Antennas and Propagation, vol. 41, no. 6, 1993.
[16] T. S. Rappaport, “Wireless Communication Principles and Practice,” Prentice-Hall, USA, 2002.
[17] Wong, J.W., Sauve, J.P., and Field, J.A., (1982), A Study of Fairness in Packet Switching Networks, IEEE Transactions on Communications, vol. 30, no. 2.
[18] M. Ehrgott, “Multicriteria Optimization,” Springer, Germany, 2005.
[19] F. Pernodet, H. Lahmidi, and P. Michel, “Use of Genetic Algorithms for Multicriteria Optimization of Building Refurbishment, “Eleventh International IBPSA Conference, Glasgow, Scotland, 2009.
[20] E. K. P. Chong, and S. H. Zak, “An Introduction to Optimization,” Third Edition, John Wiley & Sons, USA, 2008.
[21] T. Ozcelebi, , Multi-Objective Optimization for Video Streaming, PhD Thesis, Graduate School of Sciences and Engineering, Koc University, 2006.
[22] B. E. Cohanim, J. N. Hewitt, and O. de Weck, “The Design of Radio Telescope Array
Configurations using Multiobjective Optimization: Imaging Performance versus Cable Length,” The Astrophysical Journal Supplement Series, Volume 154, Issue 2, pp. 705-719, 2004.
[23] S. Capkun, M. Hamdi, and J. P. Hubaux, “GPS-free positioning in mobile Ad-Hoc networks,” Proceedings of the 34th Hawaii International Conference on System Sciences, 2001.
[24] M. Salem, A. Adinoyi, M. Rahman, H. Yanikomeroglu, D. Falconer, Kim Young-Doo, E. Kim, Y. C. Cheong, “An Overview of Radio Resource Management in Relay-Enhanced OFDMA-Based Networks, IEEE Communications Surveys & Tutorial, vol. 12, no. 3, 2010.
Nyoman Gunantara received the B.Eng. degree in electrical engineering from Universitas Brawijaya (UB), Indonesia, in 1997. In 1997 - 2000, he worked in SIEMENS as The Leader of Cable Tester Unit.
He was responsible for the quality of the cable network and cooperation with PT. TELKOM Indonesia. Since 2001, he joined with Universitas Udayana (Unud), Bali as lecturer. He received M.Eng degree in electrical engineering from Insitut Teknologi Sepuluh Nopember (ITS), Indonesia, in 2006. He is currently working toward the Ph.D. degree in electrical engineering from ITS. His research interests include wireless communications, ad hoc network, quality network, and optimization. He is a Student Member of the IEEE.
Gamantyo Hendrantoro received the B.Eng degree in electrical engineering from Institut Teknologi Sepuluh Nopember (ITS), Indonesia, in 1992, and the MEng and PhD degrees in electrical engineering
from Carleton University, Canada, in 1997 and 2001, respectively. He is presently a Professor with ITS.
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 94 Issue 3, Volume 12, March 2013
His research interests include radio propagation modeling and wireless communications. Dr. Hendrantoro is a Member of the IEEE.
WSEAS TRANSACTIONS on COMMUNICATIONS Nyoman Gunantara, Gamantyo Hendrantoro
E-ISSN: 2224-2864 95 Issue 3, Volume 12, March 2013
