01897nas a2200193 4500008004100000245008900041210006900130300001400199490000700213520123400220653000801454653000801462653000901470100002101479700002201500700002401522700001901546856013801565 2013 eng d00aApplication Layer Forward Error Correction for Multicast Streaming over LTE Networks0 aApplication Layer Forward Error Correction for Multicast Streami a1459-15740 v263 a

The next step beyond third generation (3G) mobile networks is the Third Generation Partnership Project (3GPP) standard, named Long Term Evolution (LTE). A key feature of LTE is the enhancement of Multimedia Broadcast/Multicast Services (MBMS), where the same content is transmitted to multiple users located in a specific service area. To support efficient download and streaming delivery, 3GPP included an application layer Forward Error Correction (AL-FEC) technique based on the systematic fountain Raptor code, in the MBMS standard. In order to achieve protection against packet losses, Raptor codes introduce redundant packets to the transmission, i.e., the FEC overhead. In this work, we investigate the application of AL-FEC over MBMS streaming services. We consider the benefits of AL-FEC for a continuous multimedia stream transmission to multiple users and we examine how the amount of FEC redundancy can be adjusted under different packet loss conditions. For this purpose, we present a variety of realistic simulation scenarios for the application of AL-FEC and furthermore we provide an in-depth analysis of Raptor codes performance introducing valuable suggestions to achieve efficient use of Raptor codes.

10aFEC10aLTE10aMBMS1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKanakis, Nikos uhttp://telematics.upatras.gr/telematics/publications/application-layer-forward-error-correction-multicast-streaming-over-lte-networks01987nas a2200205 4500008004100000245013600041210006900177300001400246490000700260520122000267653000801487653001001495653000801505100002101513700002201534700002201556700002401578700002401602856015501626 2013 eng d00aModulation and coding scheme selection in multimedia broadcast over a single frequency network-enabled long-term evolution networks0 aModulation and coding scheme selection in multimedia broadcast o a1603-16190 v253 a

Long term evolution constitutes the next generation cellular network beyond 3G that is designed to support the explosion in demand for bandwidth-hungry multimedia services in wireless networks by providing an extremely high performance radio access technology. To support multimedia broadcast/multicast services (MBMS), long term evolution offers the functionality to transmit MBMS over a single frequency network, where a time-synchronized common waveform is transmitted from multiple cells for a given duration. This enables over-the-air combining, thus significantly improving the spectral efficiency (SE) compared with conventional MBMS operations. In MBMS over a single frequency network transmissions, the achieved SE is mainly determined by the modulation and coding scheme selected. This study proposes and evaluates four approaches for the selection of the modulation and coding scheme. Each approach corresponds to different users? distribution and multimedia traffic conditions. On the basis of SE measurements, we determine the approach that either maximizes or achieves a target SE for the corresponding users? distribution and traffic conditions. Copyright © 2011 John Wiley & Sons, Ltd.

10aLTE10aMBSFN10aMCS1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/modulation-and-coding-scheme-selection-multimedia-broadcast-over-single-frequency-network-enabled02370nas a2200205 4500008004100000245009500041210006900136300001200205520163600217653001801853653000801871653001001879100002101889700002201910700002201932700002401954700002701978700002102005856013802026 2012 eng d00aCost Optimization of MBSFN and PTM Transmissions for Reliable Multicasting in LTE Networks0 aCost Optimization of MBSFN and PTM Transmissions for Reliable Mu a277-2933 aLong Term Evolution (LTE) systems have been specified and designed to accommodate small, high performance, power-efficient, end-user devices. The evolved Multimedia Broadcast/Multicast Service (e-MBMS) feature is introduced by the 3rd Generation Partnership Project (3GPP) as a complement to the existing MBMS service in order to accommodate multicast groups that are interested in receiving the same data. MBMS service is provided by MBMS over a Single Frequency Network (MBSFN) and/or Point-To-Multipoint (PTM) transmission methods. One of the challenges of MBMS is the complete error recovery of the transmitted files, a matter of great importance since the distribution of binary data must result in 100% error-free download. To fulfill this tight requirement, Forward Error Correction (FEC) mechanism has been proposed by 3GPP. In this work, we investigate the reliable multicasting by introducing a transmission method that combines the advantages of MBSFN and PTM transmission methods. We compare several FEC-based file recovery methods and evaluate them against various network parameters in a realistic simulation environment. The comparison is based on a cost-oriented analysis of MBMS service that takes into account the transmission cost over all the interfaces and nodes of the LTE architecture. The simulation results are performed with the aid of a new simulation tool and show that the performance of the file repair schemes depend on the network configuration. KEYWORDS: multimedia multicasting; cellular networks; forward error correction; reliability; single frequency network; optimization; point to multipoint;10aCost analysis10aLTE10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aAsimakis, Konstantinos1 aTseliou, Georgia uhttp://telematics.upatras.gr/telematics/publications/cost-optimization-mbsfn-and-ptm-transmissions-reliable-multicasting-lte-networks01812nas a2200193 4500008004100000245005900041210005900100260001300159300001000172520121800182653000801400653000801408653000901416100002101425700002201446700002401468700001901492856010701511 2012 eng d00aEnhaning Reliable Mobile Multicasting with RaptorQ FEC0 aEnhaning Reliable Mobile Multicasting with RaptorQ FEC c1-4 July a82-873 aA crucial point on the successful deployment of multicast services is the enhanced reliability by means of advanced error control schemes. To this direction Third Generation Partnership Project (3GPP) has standardized exclusively for Multimedia Broadcast/Multicast Services (MBMS) the use of a Forward Error Correction (FEC) mechanism on the application layer based on Raptor codes. Since the standardized systematic, fountain Raptor code is now considered obsolete, the emergence of a new variant of Raptor codes, named RaptorQ, provides enhanced capabilities for mobile multicast services. In this paper, we provide a performance comparison of the standardized Raptor Application Layer FEC (AL-FEC) scheme with the very promising RaptorQ FEC code. We examine the enhancements that RaptorQ introduces on the AL-FEC protection robustness, providing a thorough performance analysis in comparison with the current Raptor FEC scheme. Furthermore, in order to verify the improved performance of RaptorQ, we provide several simulation results utilizing the ns-3 environment, considering the application of both the examined AL-FEC schemes over multicast services for next generation mobile networks.10aFEC10aLTE10aMBMS1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKanakis, Nikos uhttp://telematics.upatras.gr/telematics/publications/enhaning-reliable-mobile-multicasting-raptorq-fec01589nas a2200193 4500008004100000245005600041210005600097260001700153300001400170520099100184653000801175653000801183653000901191100002101200700002201221700002401243700001901267856010901286 2012 eng d00aEvaluating RaptorQ FEC over 3GPP Multicast Services0 aEvaluating RaptorQ FEC over 3GPP Multicast Services cAugust 27-31 a257 - 2623 aThird Generation Partnership Project (3GPP) introduced Multimedia Broadcast/Multicast Services (MBMS), in order to efficiently deliver the same content to multiple users over mobile cellular networks. To enhance the download and streaming delivery robustness against packet losses, 3GPP proposes the use of Forward Error Correction (FEC) on the application layer. The Application Layer FEC (AL-FEC) scheme that 3GPP standardized is based on the systematic, fountain Raptor code. In this work, in response to the emergence of an enhanced FEC scheme, we provide a performance evaluation of the existing standardized AL-FEC scheme with the newly introduced RaptorQ code. Introducing a variety of simulation experiments, we analyze the performance behavior of each AL-FEC scheme considering several FEC encoding parameters. Furthermore, we try to verify the improvements that have emerged in AL-FEC providing enhanced capabilities in multicast services over next generation mobile networks.10aFEC10aLTE10aMBMS1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKanakis, Nikos uhttp://telematics.upatras.gr/telematics/publications/evaluating-raptorq-fec-over-3gpp-multicast-services01447nas a2200193 4500008004100000245007600041210006900117260002000186300001000206520079400216653000801010653000901018653001001027100002101037700002201058700002401080700002701104856012201131 2012 eng d00aGenetic Optimization for Spectral Efficient Multicasting in LTE Systems0 aGenetic Optimization for Spectral Efficient Multicasting in LTE  c19-21 September a54-593 a

Past research has proposed the usage of assisting cells with Multimedia Broadcast/Multicast Service (MBMS) over a Single Frequency Network (MBSFN) to increase the Spectral Efficiency (SE) of LTE. In this paper we propose and investigate a method for optimizing the power consumption of the network while retaining an acceptable SE for most users. We design an algorithm that makes use of genetic optimization and analytical estimation of the SE. The algorithm is implemented in a novel simulation tool that allows experimentation over various user distributions and LTE deployments similar to the real-world ones. This simulation tool estimates the SE of each user and is able to optimize the network deployment by adjusting the individual transmission power levels for each cell.

10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aAsimakis, Konstantinos uhttp://telematics.upatras.gr/telematics/publications/genetic-optimization-spectral-efficient-multicasting-lte-systems01490nas a2200181 4500008004100000245009400041210006900135260001600204520082500220653001401045653000801059653000801067100002101075700002201096700002401118700002501142856014101167 2012 eng d00aInterference Management in LTE Femtocell Systems Using an Adaptive Frequency Reuse Scheme0 aInterference Management in LTE Femtocell Systems Using an Adapti c18-20 April3 aLong Term Evolution (LTE) has developed a new technology in order to enhance indoor coverage. This new technology is called femtocells and is achieved with the use of access points installed by home users. However, interference problem between the femtocell and the macrocell decreases the system's capacity and as a result users' throughput. In this paper we study the interference mitigation techniques in femtocell/macrocell networks and we propose a frequency reuse mechanism that leads to increased overall system performance. In particular, the mechanism aims to maximize throughput via a variety of combinations between inner cell radius and frequency allocation to the macrocell. Additionally, a position minded frequency allocation to the femtocells targets to further optimize the total throughput of the cell.10aFemtocell10aFFR10aLTE1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKavourgias, Georgios uhttp://telematics.upatras.gr/telematics/publications/interference-management-lte-femtocell-systems-using-adaptive-frequency-reuse-scheme01532nas a2200193 4500008004100000245004400041210004400085260001500129300001200144520095800156653000801114653000901122100002101131700002201152700002201174700002401196700002401220856009401244 2012 eng d00aMultimedia Broadcasting in LTE Networks0 aMultimedia Broadcasting in LTE Networks bIGI Global a269-2893 a

Long Term Evolution (LTE) constitutes the latest step before the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile communications. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers the functionality to transmit MBMS over Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. In MBSFN transmissions, the achieved Spectral Efficiency (SE) is mainly determined by the Modulation and Coding Scheme (MCS) selected. This study proposes and evaluates four approaches for the selection of the MCS that will be utilized for the transmission of the MBSFN data. The evaluation of the approaches is performed for different users? distribution and from SE perspective. Based on the SE measurement, we determine the approach that either maximizes or achieves a target SE for the corresponding users? distribution.

10aLTE10aMBMS1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/multimedia-broadcasting-lte-networks01524nas a2200193 4500008004100000245007900041210006900120260001400189300001400203520086100217653000801078653000801086100002101094700002201115700002401137700002101161700002201182856012601204 2012 eng d00aOptimization of Fractional Frequency Reuse in Long Term Evolution Networks0 aOptimization of Fractional Frequency Reuse in Long Term Evolutio c1-4 April a1875-18793 aIn cellular systems, Fractional Frequency Reuse (FFR) partitions each cell into two regions; inner region and outer region and allocates different frequency band to each region. Since the users at the inner region are less exposed to inter-cell interference, the frequency resources in each inner region can be universally used. Based on this frequency band allocation, FFR may reduce channel interference and offer large system capacity. This paper proposes a mechanism that selects the optimal FFR scheme based on the user throughput and user satisfaction. In detail, the mechanism selects the optimal size of the inner and outer region for each cell as well as the optimal frequency allocation between these regions that either maximizes the mean user throughput or the user satisfaction. The mechanism is evaluated through several simulation scenarios.10aFFR10aLTE1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTseliou, Georgia1 aBilios, Dimitrios uhttp://telematics.upatras.gr/telematics/publications/optimization-fractional-frequency-reuse-long-term-evolution-networks01934nas a2200181 4500008004100000245005800041210005800099300001200157490000700169520136300176653000801539653001001547100002101557700002201578700002401600700002401624856010401648 2012 eng d00aPerformance Evaluation of LTE for MBSFN Transmissions0 aPerformance Evaluation of LTE for MBSFN Transmissions a227-2400 v183 a

Long Term Evolution (LTE) is the most promised latest step towards the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile communications with main target the support of the so-called “Mobile Broadband”. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers the possibility to transmit Multimedia Broadcast multicast service over a Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. In this manuscript we analytically present the MBSFN delivery method and evaluate its performance. The critical parameters of primary interest for the evaluation of the scheme are the packet delivery cost and its scalability. To this direction, a telecommunication cost analysis of the MBMS service is presented based on the transmission cost over the air interface, as well as the costs of all interfaces and nodes of the MBSFN architecture. Based on this cost analysis we determine the ideal number of cells that should participate in the MBSFN transmission in order to improve the overall MBSFN performance. Since the performance of the MBSFN scheme mainly depends on the configuration of the LTE network that is under investigation, we consider different network topologies, MBSFN deployments and user distributions.

10aLTE10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/performance-evaluation-lte-mbsfn-transmissions01744nas a2200193 4500008004100000245007200041210006900113260002000182300001200202520109300214653000801307653000801315100002101323700002201344700002401366700002101390700002201411856011701433 2012 eng d00aA Performance Study of Fractional Frequency Reuse in OFDMA Networks0 aPerformance Study of Fractional Frequency Reuse in OFDMA Network c19-21 September a38 - 433 a

Long Term Evolution (LTE) technology is considered as the most possible candidate for next generation mobile communications. LTE networks offer high capacity and are specified and designed to accommodate small, high performance, power-efficient end-user devices. One limiting factor that influences LTE performance is the interference from neighbor cells, the so called Inter-Cell Interference (ICI). Fractional Frequency Reuse (FFR) has been proposed as a technique to overcome this problem, since it can efficiently utilize the available frequency spectrum. This paper analyzes the FFR scheme and proposes a dynamic FFR mechanism that selects the optimal frequency allocation based on the cell total throughput and user satisfaction. In detail, the mechanism divides the cell into two regions (inner and outer) and selects the optimal size as well as the optimal frequency allocation between these regions with main target to maximize the overall throughput and user satisfaction. The mechanism is evaluated through several simulation scenariosthat incorporate users? mobility.

10aFFR10aLTE1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTseliou, Georgia1 aBilios, Dimitrios uhttp://telematics.upatras.gr/telematics/publications/performance-study-fractional-frequency-reuse-ofdma-networks01663nas a2200181 4500008004100000245006900041210006600110260002000176300001200196520104600208653001401254653000801268100002101276700002201297700002401319700002901343856010901372 2012 eng d00aA Simulation Framework for LTE-A Systems with Femtocell Overlays0 aSimulation Framework for LTEA Systems with Femtocell Overlays c21 - 25 October a85 - 903 aThe use of femtocells is an efficient way to improve cover- age and quality of service while on the other side the deployment cost for the service provider is kept in extremely low level. Long Term Evolution Advanced (LTE-A) systems with femtocell overlays aim to provide better indoor voice and data coverage and to increase network capacity. One of the major technical challenges that femtocell networks are facing nowadays, is the cross-tier interference, i.e., the interference between the femto base stations and the macrocell infrastructure. To this direction, we have designed and implemented a framework that simulates femtocell overlays integrated over LTE-A macrocellular systems. This framework focuses on the impact of cross-tier interference and furthermore is able to estimate the throughput at every point of integrated femtocell/macrocell LTE-A networks. In this paper, we present the design and implementation of this simulation framework and we provide significant experimental results obtained with the aid of this system.10aFemtocell10aLTE1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKontodimas, Konstantinos uhttp://telematics.upatras.gr/telematics/publications/simulation-framework-lte-systems-femtocell-overlays01977nas a2200193 4500008004100000245005100041210005000092260001800142300001200160520140000172653000801572653000801580653000901588100002101597700002201618700002401640700001901664856010001683 2011 eng d00aAL-FEC for Streaming Services over LTE Systems0 aALFEC for Streaming Services over LTE Systems cOctober 3 - 6 a284-2883 a

The Third Generation Partnership Project (3GPP), recently introduced the evolution of the third generation (3G) cellular networks, the Long Term Evolution (LTE) telecommunication system. A key aspect of LTE specifications is the enhancement of Multimedia Broadcast/Multicast Services (MBMS), where the same content is transmitted to multiple users located in a specific service area. A significant point of the demanding multimedia services is the enhancement of the robustness against packet losses. To this direction, in order to support the efficient point-to-multipoint download and streaming delivery, 3GPP has included an Application Layer Forward Error Correction (AL-FEC) scheme in the MBMS standard. The standardized AL-FEC scheme is based on the systematic, fountain Raptor codes. In this paper, we investigate the application of AL-FEC over the MBMS streaming delivery method. We consider the benefits of AL-FEC for a seamless multimedia streaming transmission to multiple mobile users and we examine how the amount of FEC overhead can be adjusted under different packet loss conditions. For this purpose, we present a variety of realistic simulation scenarios for the performance evaluation of FEC considering several network and FEC encoding parameters. Furthermore, we provide suggestions in order to achieve efficient use of Raptor codes over LTE MBMS streaming services.

10aFEC10aLTE10aMBMS1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKanakis, Nikos uhttp://telematics.upatras.gr/telematics/publications/al-fec-streaming-services-over-lte-systems01786nas a2200193 4500008004100000245009000041210006900131300001300200520110000213653000801313653000901321653001001330100002101340700002201361700002201383700002401405700002701429856013601456 2011 eng d00aCombining MBSFN and PTM Transmissions Schemes for Resource Efficiency in LTE Networks0 aCombining MBSFN and PTM Transmissions Schemes for Resource Effic a 56 - 673 aLong Term Evolution (LTE) systems allow the transmission of rich multimedia services by utilizing the Multimedia Broadcast/Multicast Service (MBMS) over a Single Frequency Network (MBSFN). During MBSFN transmission a time-synchronized common waveform is transmitted from multiple cells. The 3rd Generation Partnership Project (3GPP) has specified that Point-to-Multipoint (PTM) transmission can be used in combination with MBSFN to provide MBMS-based services. In this paper we evaluate the combined transmission scheme in terms of Resource Efficiency (RE). The evaluation is performed through simulation experiments for various user distributions and LTE network configurations. The experiments are conducted with the aid of a proposed algorithm, which estimates the Spectral Efficiency (SE) of each cell and the RE of the network, and is also able to formulate the optimal network deployment that maximizes the network?s RE. For each of the examined scenarios, we present the most efficient solution (in terms of RE) selected by our algorithm and we compare it with other transmission schemes.10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aAsimakis, Konstantinos uhttp://telematics.upatras.gr/telematics/publications/combining-mbsfn-and-ptm-transmissions-schemes-resource-efficiency-lte-networks00635nas a2200181 4500008004100000245007900041210006900120260001100189300001500200653000800215653000800223653000900231100002100240700002200261700002400283700002100307856012500328 2011 eng d00aForward Error Correction for Reliable e-MBMS Transmissions in LTE Networks0 aForward Error Correction for Reliable eMBMS Transmissions in LTE bInTech a 353 - 37410aFEC10aLTE10aMBMS1 aBouras, Christos1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTseliou, Georgia uhttp://telematics.upatras.gr/telematics/publications/forward-error-correction-reliable-e-mbms-transmissions-lte-networks01668nas a2200181 4500008004100000245007300041210006900114260002600183520101400209653001401223653000801237100002101245700002201266700002201288700002401310700002901334856012301363 2011 eng d00aInterference Behavior of Integrated Femto and Macrocell Environments0 aInterference Behavior of Integrated Femto and Macrocell Environm cOctober 10 – 123 aAbstract—Femtocells are data access points installed by the subscribers to provide better indoor voice and data coverage and to increase system capacity. The integrated femtocell/macrocell networks offer an efficient way to increase access capacity by improving coverage and quality of service while on the other side the deployment cost for the service provider is kept in extremely low levels. One of the major technical challenges that femtocell networks are facing is their interference behavior when they are placed within macrocells. The study presented in this paper focuses on the impact of integrating femtocells in macrocell networks in terms of adjacent cell interference that the macrocell environment adds to users served by a femto base station and vice versa. To this direction, we have designed and implemented a simulation testbed that estimates the cross-tier interference and the throughput in every point of an integrated femtocell/macrocell Long Term Evolution-Advanced (LTE-A) network.10aFemtocell10aLTE1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aKontodimas, Konstantinos uhttp://telematics.upatras.gr/telematics/publications/interference-behavior-integrated-femto-and-macrocell-environments01741nas a2200193 4500008004100000245007700041210006900118260001600187520108700203653000801290653000901298653001001307100002101317700002201338700002201360700002401382700002101406856012001427 2011 eng d00aOptimizing the Combination of MBSFN and PTM Transmissions in LTE Systems0 aOptimizing the Combination of MBSFN and PTM Transmissions in LTE cApril 13-153 aThe 3rd Generation Partnership Project (3GPP) has introduced the evolved Multimedia Broadcast/Multicast Service (e-MBMS) feature for cellular systems as an evolution to the existing MBMS service. To support e-MBMS in Long Term Evolution (LTE) systems, 3GPP recommends the use of Point-to- Multipoint (PTM) transmissions and MBMS over a Single Frequency Network (MBSFN). MBSFN is a new feature where a time-synchronized common waveform is transmitted from multiple cells. In this paper we investigate the provision of MBMS service over a combination of MBSFN and PTM transmission methods. A cost analysis of the MBMS service is presented based on the transmission cost over all the interfaces and nodes of the LTE architecture. We evaluate the performance of this transmission scheme from telecommunication cost perspective and we compare it with other transmission schemes. The performance evaluation has been performed with the aid of a new simulation tool that estimates the cost for the MBMS provision under different network topologies, MBSFN deployments and user distributions.10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTseliou, Georgia uhttp://telematics.upatras.gr/telematics/publications/optimizing-combination-mbsfn-and-ptm-transmissions-lte-systems01730nas a2200229 4500008004100000245005600041210005500097260002100152300001500173520103400188653000801222653000801230653000901238653001001247100002101257700002201278700002201300700002401322700002701346700002101373856010601394 2011 eng d00aReliable Multicasting over LTE: A Performance Study0 aReliable Multicasting over LTE A Performance Study cJune 28 - July 1 a 603 - 6083 aWith the booming of multimedia services, the 3rd Generation Partnership Project (3GPP) has introduced the evolved Multimedia Multicast/Broadcast Service (e-MBMS) feature for LTE systems. The main objective of MBMS is to introduce real broadcast distribution capabilities into cellular systems. This purposed 3GPP to introduce the MBMS over a Single Frequency Network (MBSFN) operation. In this work we investigate the provision of MBMS service over a combination of MBSFN and PTM transmission schemes. We focus on the file repair procedure, because the distribution of binary data via MBMS must result in 100% error-free downloaded files. In order to achieve this goal, MBMS offers a Forward Error Correction (FEC) mechanism. Our simulation results show that there are some file repair schemes that achieve better performance as far as different network configurations are concerned. Furthermore, we compare all the file recovery methods and evaluate them against various network parameters in a realistic simulation environment.10aFEC10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aAsimakis, Konstantinos1 aTseliou, Georgia uhttp://telematics.upatras.gr/telematics/publications/reliable-multicasting-over-lte-performance-study01180nas a2200205 4500008004100000245006100041210006100102260002000163300001500183520052800198653000800726653000800734653000900742100002100751700002200772700002200794700002400816700002400840856011000864 2010 eng d00aAdopting FEC for Reliable Multicasting over LTE Networks0 aAdopting FEC for Reliable Multicasting over LTE Networks cOctober 17 - 21 a 307 - 3103 aThe key feature for the provision of Multimedia Broadcast/Multicast Services (MBMS) in Long Term Evolution (LTE) networks is the Multimedia Broadcast over a Single Frequency Network (MBSFN). On the other hand, the use of Forward Error Correction (FEC) in mobile multicast transmission has significant advantages and the 3rd Generation Partnership Project (3GPP) has adopted the application layer FEC in the MBMS standard. In this paper, we investigate the impact of the application layer FEC over the MBSFN delivery method.10aFEC10aLTE10aMBMS1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/adopting-fec-reliable-multicasting-over-lte-networks01631nas a2200193 4500008004100000245007800041210006900119260001900188300001200207520099100219653000801210653000801218653000901226653001001235100002101245700002201266700002201288856012701310 2010 eng d00aAdopting forward error correction for multicasting over cellurar networks0 aAdopting forward error correction for multicasting over cellurar c12 - 15 April  a307-3103 a

FEC is an error control method that can be used to augment or replace other methods for reliable data transmission. Such schemes inevitably add a constant overhead in the transmitted data. However, they are so simple as to meet a prime objective for UMTS multicast services, that is scalability to applications with thousands of receivers. This is the reason that 3GPP recommends the use of FEC for MBMS framework. In this paper, we use a probabilistic model for the multicast user distribution in the network and we define a scheme for multicast data delivery that combines FEC with traditional ARQ. It is important that our analysis is compliant with the 3GPP specifications and considers the latest advances in mobile networks. In this framework we investigate the impact of FEC use, we examine whether it is beneficial, how the optimal FEC code dimensioning varies based on the network conditions, which parameters affect the optimal FEC code selection, and how they do it.

10aFEC10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas uhttp://telematics.upatras.gr/telematics/publications/adopting-forward-error-correction-multicasting-over-cellurar-networks01688nas a2200193 4500008004100000245004800041210004800089260002200137300001500159520109800174653001801272653000801290653001001298100002101308700002201329700002401351700002401375856009501399 2010 eng d00aCommunication Cost Analysis of MBSFN in LTE0 aCommunication Cost Analysis of MBSFN in LTE cSeptember 26 - 30 a 1366-13713 aLong Term Evolution (LTE) is the latest step towards the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile communications. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers the possibility to transmit Multimedia Broadcast multicast service over a Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. In this paper we analytically present the MBSFN delivery method and evaluate its performance. The critical parameters of primary interest for the evaluation of the scheme are the packet delivery cost and its scalability. To this direction, a telecommunication cost analysis of the MBMS service is presented based on the transmission cost over the air interface, as well as the costs of all interfaces and nodes of the MBSFN architecture. Since the performance of the MBSFN scheme mainly depends on the configuration of the LTE network that is under investigation, we consider different network topologies, MBSFN deployments and user distributions.10aCost analysis10aLTE10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/communication-cost-analysis-mbsfn-lte01695nas a2200205 4500008004100000245007000041210006900111260002000180520102200200653000801222653000901230653001001239653000801249100002101257700002201278700002201300700002401322700002401346856011901370 2010 eng d00aEfficient MCS Selection for MBSFN Transmissions over LTE Networks0 aEfficient MCS Selection for MBSFN Transmissions over LTE Network cOctober 20 - 223 aLong Term Evolution (LTE), the next-generation network beyond 3G, is designed to support the explosion in demand for bandwidth-hungry multimedia services that are already experienced in wired networks. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers functionality to transmit MBMS over a Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. This significantly improves the Spectral Efficiency (SE) compared to conventional MBMS operation. The achieved SE is mainly determined by the Modulation and Coding Scheme (MCS) utilized by the LTE physical layer. In this paper we propose and evaluate four approaches for the selection of the MCS that will be utilized for the transmission of the MBSFN data. The evaluation of the approaches is performed for different users? distribution and from SE perspective. Based on the SE measurement, we determine the most suitable approach for the corresponding users? distribution.10aLTE10aMBMS10aMBSFN10aMCS1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/efficient-mcs-selection-mbsfn-transmissions-over-lte-networks01642nas a2200181 4500008004100000245006100041210006000102260001500162300001500177520105500192653000801247653000901255653001801264100002101282700002201303700002401325856011101349 2010 eng d00aEfficient Power Allocation in E-MBMS Enabled 4G Networks0 aEfficient Power Allocation in EMBMS Enabled 4G Networks bIGI Global a 458 - 4883 a

The plethora of mobile multimedia services that are expected to face high penetration, poses the need for the deployment of a resource economic scheme in Long Term Evolution (LTE) networks. To this direction, the Evolved - Multimedia Broadcast / Multicast Service (E- MBMS) is envisaged to play an instrumental role for LTE proliferation and set the basis for a successful 4th Generation (4G) standardization process. One of the most critical aspects of E- MBMS performance is the selection of the most efficient radio bearer, in terms of power consumption. This chapter presents the prevailing radio bearer selection mechanisms and examines their performance in terms of power consumption. Furthermore, it discusses problems regarding the high power requirements for the realization of E-MBMS and evaluates the proposed techniques/solutions. Finally, this chapter presents a novel mechanism for efficient power control during E-MBMS transmissions that conforms to LTE requirements for simultaneous provision of multiple multimedia sessions.

10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/efficient-power-allocation-e-mbms-enabled-4g-networks01662nas a2200205 4500008004100000245005500041210005500096260002000151520103500171653000801206653000801214653000901222653001001231100002101241700002201262700002201284700002401306700002101330856010501351 2010 eng d00aEnhancing FEC Application in LTE Cellular Networks0 aEnhancing FEC Application in LTE Cellular Networks cOctober 20 - 223 a3rd Generation Partnership Project?s (3GPP) Long Term Evolution (LTE) is focused on enhancing the Universal Terrestrial Radio Access (UTRA). Evolved-Multimedia Broadcast and Multicast Service (e-MBMS) uses Multimedia Broadcast over a Single Frequency Network (MBSFN) operation in order to improve its performance. In MBSFN operation, data are transmitted simultaneously over the air from multiple tightly time-synchronized cells. Raptor codes have been standardized as the main application layer Forward Error Correction (FEC) method for e-MBMS due to the advanced error protection they offer and their overall performance. In this study, we investigate the application of FEC in MBSFN-enabled LTE cellular networks and we propose a new scheme that takes into account the properties of MBSFN in order to provide a more efficient operation of FEC during e-MBMS transmissions. The proposed scheme is compared with other file recovery methods and is evaluated against various network parameters in a realistic simulation environment.10aFEC10aLTE10aMBMS10aMBSFN1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTseliou, Georgia uhttp://telematics.upatras.gr/telematics/publications/enhancing-fec-application-lte-cellular-networks01201nas a2200193 4500008004100000245005600041210005200097260001500149300000800164520062800172653000800800653000800808653000900816653001800825100002100843700002200864700002200886856009900908 2010 eng d00aThe Impact of FEC on Mobile Multicast Power Control0 aImpact of FEC on Mobile Multicast Power Control cMay 9 - 15 a1-63 a3GPP has standardized the use of forward error correction for the provision of reliable data transmission in the mobile multicast framework. In this paper we present a study of the impact of application layer forward error correction on power control during mobile multicast transmission. The evaluation is performed with the aid of a novel scheme that allows the simulation of FEC impact on both streaming delivery and download delivery over a multicast session. It is important that the proposed scheme incorporates the properties of an evolved mobile network, as they are determined by the 3GPP specifications.10aFEC10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas uhttp://telematics.upatras.gr/telematics/publications/impact-fec-mobile-multicast-power-control01728nas a2200181 4500008004100000245007400041210006900115300001500184490000700199520111600206653000801322653000901330653001801339100002101357700002201378700002201400856012401422 2010 eng d00aAn Improved MBMS Power Counting Mechanism towards Long Term Evolution0 aImproved MBMS Power Counting Mechanism towards Long Term Evoluti a 109 - 1190 v433 a

One of the key objectives of beyond 3rd generation mobile networks is the realization of enhanced end-user experience through the provision of rich multimedia services. Multimedia Broadcast/Multicast Services (MBMS) framework epitomizes the increasing popularity of such applications and is envisaged to play an instrumental role for the Long Term Evolution (LTE) proliferation in mobile market. For exploiting resource efficiency, MBMS specifications consider the Counting Mechanism which decides whether it is more efficient to deliver MBMS multicast traffic over Point-to-Point (PTP) or Point-to-Multipoint (PTM) bearers. However, the necessity to further improve MBMS resource efficiency and integrate new technologies in the frame of LTE stresses the need for an advanced Counting Mechanism. In this work we propose a novel Power Counting Mechanism for efficient selection of MBMS bearers. The proposed mechanism optimally utilizes power resources and exploits broadband characteristics and performance enhancements emerged from Multiple Input Multiple Output (MIMO) antennas used in LTE networks.

10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aRekkas, Evangelos uhttp://telematics.upatras.gr/telematics/publications/improved-mbms-power-counting-mechanism-towards-long-term-evolution01827nas a2200181 4500008004100000245006700041210006600108260006300174300001500237520117500252653000801427653000901435653001801444100002101462700002201483700002401505856011601529 2010 eng d00aRadio Resource Management for E-MBMS Transmissions towards LTE0 aRadio Resource Management for EMBMS Transmissions towards LTE bAuerbach Publications, CRC Press, Taylor and Francis Group a 331 - 3603 a

Long Term Evolution (LTE) constitutes a key standard that paves the way for the future mobile broadband landscape envisioned by 4th Generation (4G) wireless networks. Actu- ally, LTE addresses the emerging trend for the mass provision of rich multimedia services, such as Mobile TV, in a more power and spectral e±cient way than its predecessors. To this direction, the Evolved - Multimedia Broadcast/Multicast Service (E-MBMS) frame- work is envisaged to play an instrumental role for the LTE proliferation in mobile. E-MBMS constitutes the evolutionary successor of MBMS, which was introduced in the Release 6 of Universal Mobile Telecommunication System (UMTS). MBMS is designed in order to deliver multimedia data from a single source entity to multiple destinations. However, downlink ca- pacity in such networks is limited by base station transmission power. As an aftermath, in MBMS e±cient power allocation techniques should be implemented so as to ensure the mass provision of multimedia applications to mobile users. This chapter presents several techniques and mechanisms used today for MBMS power optimization in next generation cellular networks.

10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/radio-resource-management-e-mbms-transmissions-towards-lte01664nas a2200217 4500008004100000245006600041210006500107260002000172300001500192520097500207653000801182653000901190653001001199653000801209100002101217700002201238700002201260700002401282700002401306856011601330 2010 eng d00aSpectral Efficiency Performance of MBSFN-enabled LTE Networks0 aSpectral Efficiency Performance of MBSFNenabled LTE Networks cOctober 11 - 13 a 361 - 3673 aLong Term Evolution (LTE) constitutes the latest step before the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile communications. To support Multimedia Broadcast/Multicast Services (MBMS), LTE offers the possibility to transmit Multimedia Broadcast multicast service over a Single Frequency Network (MBSFN), where a time-synchronized common waveform is transmitted from multiple cells for a given duration. This enables over-the-air combining, thus improving the Signal to Interference plus Noise Ratio (SINR) and spectral efficiency (SE) significantly compared to conventional MBMS operation. In this paper, we analytically calculate the SE performance achieved in a MBSFN area for a dynamically changing user topology and different modulation and coding schemes (MCS). Finally, based on the SE measurement, we determine the MCS scheme that either maximizes or achieves a target SE for the corresponding user distribution.10aLTE10aMBMS10aMBSFN10aMCS1 aBouras, Christos1 aAlexiou, Antonios1 aPapazois, Andreas1 aKokkinos, Vasileios1 aTsichritzis, George uhttp://telematics.upatras.gr/telematics/publications/spectral-efficiency-performance-mbsfn-enabled-lte-networks01554nas a2200169 4500008004100000245006400041210006300105260002100168300001500189520098200204653000801186653000901194100002101203700002201224700002401246856011401270 2009 eng d00aEfficient Assignment of Multiple E-MBMS Sessions toward LTE0 aEfficient Assignment of Multiple EMBMS Sessions toward LTE c9 - 11 September a 240 - 2503 aOne of the major prerequisites for Long Term Evolution (LTE) networks is the mass provision of multimedia services to mobile users. To this end, Evolved - Multimedia Broadcast/Multicast Service (E-MBMS) is envisaged to play an instrumental role during LTE standardization process and ensure LTE?s proliferation in mobile market. E-MBMS targets at the economic delivery, in terms of power and spectral efficiency, of multimedia data from a single source entity to multiple destinations. This paper proposes a novel mechanism for efficient radio bearer selection during E-MBMS transmissions in LTE networks. The proposed mechanism is based on the concept of transport channels combination in any cell of the network. Most significantly, the mechanism manages to efficiently deliver multiple E-MBMS sessions. The performance of the proposed mechanism is evaluated and compared with several radio bearer selection mechanisms in order to highlight the enhancements that it provides.10aLTE10aMBMS1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/efficient-assignment-multiple-e-mbms-sessions-toward-lte01663nas a2200169 4500008004100000245007300041210006900114260001800183520106700201653000801268653000901276653001801285100002101303700002201324700002401346856012301370 2009 eng d00aAn Enhanced MBMS Power Control Mechanism towards Long Term Evolution0 aEnhanced MBMS Power Control Mechanism towards Long Term Evolutio c22 - 24 April3 aLong Term Evolution (LTE) promises the delivery of rich multimedia services in a more power and spectral efficient way than its predecessor Universal Mobile Telecommunication System (UMTS). To this direction, the newly introduced Enhanced - Multimedia Broadcast/Multicast Service (E-MBMS) framework is envisaged to play a fundamental role during the LTE standardization. E-MBMS constitutes the successor of MBMS which was introduced in the Release 6 of UMTS in order to deliver multimedia data from a single source entity to multiple destinations. This paper proposes a novel mechanism for efficient radio bearer selection during E-MBMS transmissions in LTE networks. The proposed mechanism is based on the concept of transport channels combination (pointto- point and/or point-to-multipoint radio bearers) in any cell/sector of the network in which multicast users are residing. The mechanism is evaluated through several realistic scenarios and is compared with several radio bearer selection mechanisms in order to highlight the enhancements that it provides.10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/enhanced-mbms-power-control-mechanism-towards-long-term-evolution01919nas a2200193 4500008004100000245008400041210006900125260002000194300001500214520125800229653000801487653000901495653001801504653000901522100002101531700002201552700002401574856012701598 2009 eng d00aAn Enhanced Mechanism for Efficient Assignment of Multiple sessions towards LTE0 aEnhanced Mechanism for Efficient Assignment of Multiple sessions c26 - 30 October a 384 - 3913 aThe provision of rich multimedia services, such as Mobile TV, is considered of key importance for the Long Term Evolution (LTE) proliferation in mobile market. To this direction, Evolved - Multimedia Broadcast/Multicast Service (E-MBMS) that targets at the efficient delivery of multimedia data from a single source entity to multiple destinations, is envisaged to play an instrumental role during LTE standardization process. However, both LTE and E-MBMS performance are limited by the base station?s transmission power. As an aftermath, efficient power allocation techniques should be implemented so as to ensure the mass provision of multimedia applications to mobile users. This paper proposes a novel mechanism for efficient radio bearer selection during E-MBMS transmissions in LTE networks. The proposed mechanism is based on the concept of transport channels combination in any cell of the network. Most significantly, the mechanism exploits the performance enhancements emerged from Multiple Input Multiple Output (MIMO) antennas used in LTE networks and manages to efficiently deliver multiple E-MBMS sessions. The proposed mechanism is thoroughly evaluated and compared with several radio bearer selection mechanisms existing in bibliography.10aLTE10aMBMS10aPower Control10aUMTS1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/enhanced-mechanism-efficient-assignment-multiple-sessions-towards-lte01687nas a2200157 4500008004100000245007000041210006900111520113100180653000801311653000901319653001801328100002101346700002201367700002401389856011601413 2009 eng d00aEvaluation of Different Power Saving Techniques for MBMS Services0 aEvaluation of Different Power Saving Techniques for MBMS Service3 aOver the last years we have witnessed an explosive growth of multimedia computing, wireless communication and applications. Following the rapid increase in penetration rate of broadband services, the Third Generation Partnership Project (3GPP) is currently standardizing the Evolved-Multimedia Broadcast/Multicast Service (E-MBMS) framework of Long Term Evolution (LTE), the successor ofUniversalMobile Telecommunications System (UMTS).MBMS constitutes a point-to-multipoint downlink bearer service that was designed to significantly decrease the required radio and wired link resources. However, several obstacles regarding the high-power requirements should be overcome for the realization of MBMS. Techniques, such as Macrodiversity Combining and Rate Splitting, could be utilized to reduce the power requirement of delivering multicast traffic toMBMS users. In this paper, we analytically present several power saving techniques and analyze their performance in terms of power consumption. We provide simulation results that reveal the amount of power that is saved and reinforce the need for the usage of such techniques.10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios uhttp://telematics.upatras.gr/telematics/publications/evaluation-different-power-saving-techniques-mbms-services01848nas a2200181 4500008004100000245006600041210006600107260001800173520123500191653000801426653000901434653001801443100002101461700002201482700002401504700002201528856011601550 2009 eng d00aOptimal MBMS Power Allocation Exploiting MIMO in LTE Networks0 aOptimal MBMS Power Allocation Exploiting MIMO in LTE Networks c26 - 29 April3 aIn the frame of the Long Term Evolution (LTE) of mobile networks, the provision of rich multimedia services, such as Mobile TV, is considered of key importance for the LTE proliferation in mobile market. To this end, Multimedia Broadcast/Multicast Service (MBMS) is envisaged to play an instrumental role during LTE standardization process. MBMS was introduced in the Release 6 of Universal Mobile Telecommunication System (UMTS) in order to deliver multimedia data from a single source entity to multiple destinations. However, downlink capacity in such networks is limited by base station transmission power. As an aftermath, in MBMS efficient power allocation techniques should be implemented so as to ensure the mass provision of multimedia applications to mobile users. In this paper we propose a power control scheme for efficient selection of MBMS bearers. The proposed mechanism on the one hand manages to economically utilize power resources during MBMS transmissions, while on the other hand exploits the performance enhancements emerged from Multiple Input Multiple Output (MIMO) antennas used in LTE networks. Simulation results indicate that the proposed scheme results to significant power and capacity improvements.10aLTE10aMBMS10aPower Control1 aBouras, Christos1 aAlexiou, Antonios1 aKokkinos, Vasileios1 aRekkas, Evangelos uhttp://telematics.upatras.gr/telematics/publications/optimal-mbms-power-allocation-exploiting-mimo-lte-networks