27 research outputs found

    Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems

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    (c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.[EN] 3GPP has enhanced the point-to-multipoint (PTM) communication capabilities of 4G LTE in all releases since the adoption of eMBMS in Release-9. Recent enhancements cover not only television services, but also critical machine-type and vehicular communications, following the backward-compatibility design philosophy of LTE. This article discusses the opportunity in the design and standardization of 5G to break with the existing paradigm for PTM transmissions in 4G LTE, where broadcast PTM transmissions were initially conceived as an add-on and pre-positioned service. 5G brings the opportunity to incorporate PTM capabilities as built-in delivery features from the outset, integrating point-to-point and PTM modes under one common framework and enabling dynamic use of PTM to maximize network and spectrum efficiency. This approach will open the door to completely new levels of network management and delivery cost efficiency. The article also discusses the implications of PTM for network slicing to customize and optimize network resources on a common 5G infrastructure to accommodate different use cases and services taking into account user densityThis work was supported in part by the European Commission under the 5G-PPP project Broadcast and Multicast Communication Enablers for the Fifth-(H2020-ICT-2016-2 call, grant number 761498). The views expressed in this contribution are those of the authors and do not necessarily represent the project.Generation of Wireless Systems 5G-XcastGomez-Barquero, D.; Navratil, D.; Appleby, S.; Stagg, M. (2018). Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems. IEEE Communications Standards Magazine. 2(1):53-59. https://doi.org/10.1109/MCOMSTD.2018.170006953592

    Broadcasting scalable video with generalized spatial modulation in cellular networks

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    This paper considers the transmission of scalable video via broadcast and multicast to increase spectral and energy efficiency in cellular networks. To address this problem, we study the use of generalized spatial modulation (GSM) combined with non-orthogonal hierarchical M-QAM modulations due to the capability to exploit the potential gains of large scale antenna systems and achieve high spectral and energy efficiencies. We introduce the basic idea of broadcasting/multicasting scalable video associated to GSM, and discuss the key limitations. Non-uniform hierarchical QAM constellations are used for broadcasting/multicasting scalable video while user specific messages are carried implicitly on the indexes of the active transmit antennas combinations. To deal with multiple video and dedicated user streams multiplexed on the same transmission, an iterative receiver with reduced complexity is described. 5G New Radio (NR) based link and system level results are presented. Two different ways of quadruplicating the number of broadcasting programs are evaluated and compared. Performance results show that the proposed GSM scheme is capable of achieving flexibility and energy efficiency gain over conventional multiple input multiple output (MIMO) schemes.info:eu-repo/semantics/publishedVersio

    AL-FEC for streaming services in LTE E-MBMS

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    3rd Generation Partnership Project specified Application Layer - Forward Error Correction (AL-FEC) to be used for Enhanced Multimedia Broadcast Multicast Services (E-MBMS) in Long Term Evolution (LTE) networks. Specifically, Raptor coding is applied to both streaming and file delivery services. This article focuses on streaming services and investigates the optimum configuration of the AL-FEC mechanism depending on the signal-to-interference plus noise power ratio conditions. These configurations are compared with a scenario without an application layer protection to obtain the potential gain that can be achieved by means of AL-FEC. This article also studies the multiplexing of services within the AL-FEC time interleaving. These analyses were performed using a proprietary system level simulator and assuming both pedestrian and vehicular users. Different quality criterions were used to ensure the completeness of the study. Results show the significant benefit of using AL-FEC in E-MBMS in terms of coverage and service quality.This study was supported by the Spanish Ministry of Science under the project TEC2011-27723-C02-02.Calabuig Gaspar, J.; Monserrat Del Río, JF.; Gozálvez Serrano, D.; Gómez Barquero, D. (2013). AL-FEC for streaming services in LTE E-MBMS. EURASIP Journal on Wireless Communications and Networking. 2013(73):1-12. https://doi.org/10.1186/1687-1499-2013-73S1122013733GPP TS 25.346 V6.4.0, Introduction of the Multimedia Broadcast Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2, 2005.Deng H, Tao X, Lu J: Qos-aware resource allocation for mixed multicast and unicast traffic in OFDMA networks. EURASIP Journal on Wireless Communications and Networking 2012, 2012(195):1-10. 10.1186/1687-1499-2012-1953GPP TS 26.346 V9.5.0, Multimedia Broadcast/Multicast Service (MBMS); Protocols and codecs, 2011.Shokrollahi A: Raptor codes. IEEE Transactions on Information Theory 2006, 52(6):2251-2567. 10.1109/TIT.2006.8743903GPP TS 25.346 V7.5.0, Introduction of the Multimedia Broadcast/Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2, 2007.Martín-Sacristán D, Monserrat JF, Cabrejas J, Calabuig D, Garrigas S, Cardona N: On the way towards fourth-generation mobile: 3GPP LTE and LTE-advanced. EURASIP Journal on Wireless Communications and Networking 2009, 1-10. 10.1155/2009/3540893GPP TS 36.211 V.8.5.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation, 2008.3GPP TS 36.300 V9.1.0, Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description, 2009.Monserrat JF, Calabuig J, Fernandez-Aguilella A, Gomez-Barquero D: Joint delivery of unicast and E-MBMS services in LTE networks. IEEE Transactions on Broadcasting. 2012, 58(2):157-167. 10.1109/TBC.2012.2191030Alexiou A, Bouras C, Kokkinos V, Papazois A, Tsichritzis G: Wireless Multi-Access Environments and Quality of Service Provisioning: Solutions and Application, Multimedia broadcasting in LTE networks. Edited by: Muntean GM, Trestian R. Hershey, PA: IGI Global; 2012:269-289.Wang N, Zhang Z: The impact of application layer Raptor FEC on the coverage of MBMS. Radio and Wireless Symposium, 2008 IEEE 2008, 223-226. 10.1109/RWS.2008.4463469Gomez-Barquero D, Fernandez-Aguilella A, Cardona N: Multicast delivery of file download services in evolved 3G mobile networks with HSDPA and MBMS. IEEE Transactions on Broadcasting. 2009, 55(4):742-751. 10.1109/TBC.2009.2032800Stockhammer T, Shokrollahi A, Watson M, Luby M, Gasiba T: Handbook of Mobile Broadcasting: DVB-H, DMB, ISDB-T and Media FLO, Application layer forward error correction for mobile multimedia broadcasting. Edited by: Furhet B, Ahson S. Boca Raton, FL: CRC Press; 2008:239–-280.Afzal J, Stockhammer T, Gasiba T, Xu W: Video streaming over MBMS: a system design approach. Journal of Multimedia. 2006, 1(5):25-35.Alexiou A, Bouras C, Kokkinos V, Papazois A, Tseliou G: Cellular Networks - Positioning, Performance Analysis, Reliability, Forward error correction for reliable e-MBMS transmissions in LTE networks. Edited by: Melikov A. Rijeka, Croatia: InTech; 2011:353-374.Munaretto D, Jurca D, Widmer J: Broadcast video streaming in cellular networks: An adaptation framework for channel, video and AL-FEC rates allocation. Wireless Internet Conference (WICON), 2010 The 5th Annual ICST 2010, 1-9.Bouras C, Kanakis N, Kokkinos V, Papazois A: Application layer forward error correction for multicast streaming over LTE networks. Int. J. Commun. Syst 2012. 10.1002/dac.2321RaptorQ technical overview, Qualcomm Technical Report 2010. http://www.qualcomm.com/instella_api/asset/3cd5b620-afea-012d-72bc-12313804dc61Mladenov T, Kim K, Nooshabadi S: Forward error correction with RaptorQ Code on embedded systems. Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium 2011, 1-4. 10.1109/MWSCAS.2011.6026424Calabuig J, Monserrat JF, Martín-Sacristán D, Olmos J: Comparison of multicast/broadcast services in Long Term Evolution Advanced and IEEE 802.16m networks. Wirel. Commun. Mob. Comput. 2012. 10.1002/wcm.2229Jiang X, Zhu G, Wu W, Gao Y: Design of LTE E-MBMS Dynamic Scheduling Information. Wireless Communications Networking and Mobile Computing (WiCOM), 2010 6th International Conference on 2010, 1-5. 10.1109/WICOM.2010.56002103GPP TS 36.331 V.9.9.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol Specification, 2011.Alberi Morel M-L, Kerboeuf S, Sayadi B, Leprovost Y, Faucheux F: Performance Evaluation of Channel Change for DVB-SH Streaming Services. Communications (ICC), 2010 IEEE International Conference on 2010, 1-6. 10.1109/ICC.2010.5502523WINNER + IMT-Advanced Calibration: Guidelines, software and results. 2009. http://projects.celtic-initiative.org/winner+/WINNER+%20Evaluation%20Group.htmlBrueninghaus K, Astely D, Salzer T, Visuri S, Alexiou A, Karger S, Seraji GA: Link performance models for system level simulations of broadband radio access systems, in Proceedings of 16th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC). Berlin, Germany 2005, 4: 2306-2311. 10.1109/PIMRC.2005.1651855ITU-R M.2135, Guidelines for evaluation of radio interface technologies for IMT-Advanced. 2008. http://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-M.2135-2008-PDF-E.pdf3GPP TS 36.101 V.9.10.0, Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio transmission and reception. 2011.Rong L, Ben Haddada O, Elayoubi S-E: Analytical Analysis of the Coverage of a MBSFN OFDMA Network," Global Telecommunications Conference . IEEE GLOBECOM 2008. IEEE 2008, 1-5. 10.1109/GLOCOM.2008.ECP.4593GPP TSG-SA WG4 S4-100861, Relation between MBSFN area and intended MBMS service reception area, 2010.3GPP TR 36.213 V.9.3.0, Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures, 2010

    ODZ1 allows glioblastoma to sustain invasiveness through a Myc-dependent transcriptional upregulation of RhoA

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    Long-term survival remains low for most patients with glioblastoma (GBM), which reveals the need for markers of disease outcome and novel therapeutic targets. We describe that ODZ1 (also known as TENM1), a type II transmembrane protein involved in fetal brain development, plays a crucial role in the invasion of GBM cells. Differentiation of glioblastoma stem-like cells drives the nuclear translocation of an intracellular fragment of ODZ1 through proteolytic cleavage by signal peptide peptidase-like 2a. The intracellular fragment of ODZ1 promotes cytoskeletal remodelling of GBM cells and invasion of the surrounding environment both in vitro and in vivo. Absence of ODZ1 by gene deletion or downregulation of ODZ1 by small interfering RNAs drastically reduces the invasive capacity of GBM cells. This activity is mediated by an ODZ1-triggered transcriptional pathway, through the E-box binding Myc protein, that promotes the expression and activation of Ras homolog family member A (RhoA) and subsequent activation of Rho-associated, coiled-coil containing protein kinase (ROCK). Overexpression of ODZ1 in GBM cells reduced survival of xenografted mice. Consistently, analysis of 122 GBM tumour samples revealed that the number of ODZ1-positive cells inversely correlated with overall and progression-free survival. Our findings establish a novel marker of invading GBM cells and consequently a potential marker of disease progression and a therapeutic target in GBM

    Optimized cross-layer forward error correction coding for H.264 AVC video transmission over wireless channels

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    Forward error correction (FEC) codes that can provide unequal error protection (UEP) have been used recently for video transmission over wireless channels. These video transmission schemes may also benefit from the use of FEC codes both at the application layer (AL) and the physical layer (PL). However, the interaction and optimal setup of UEP FEC codes at the AL and the PL have not been previously investigated. In this paper, we study the cross-layer design of FEC codes at both layers for H.264 video transmission over wireless channels. In our scheme, UEP Luby transform codes are employed at the AL and rate-compatible punctured convolutional codes at the PL. In the proposed scheme, video slices are first prioritized based on their contribution to video quality. Next, we investigate the four combinations of cross-layer FEC schemes at both layers and concurrently optimize their parameters to minimize the video distortion and maximize the peak signal-to-noise ratio. We evaluate the performance of these schemes on four test H.264 video streams and show the superiority of optimized cross-layer FEC design.Peer reviewedElectrical and Computer Engineerin

    Adopting a high-polyphenolic diet is associated with an improved glucose profile: prospective analysis within the PREDIMED-plus trial

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    Previous studies suggested that dietary polyphenols could reduce the incidence and complications of type-2 diabetes (T2D); although the evidence is still limited and inconsistent. This work analyzes whether changing to a diet with a higher polyphenolic content is associated with an improved glucose profile. At baseline, and at 1 year of follow-up visits, 5921 participants (mean age 65.0 ± 4.9, 48.2% women) who had overweight/obesity and metabolic syndrome filled out a validated 143-item semi-quantitative food frequency questionnaire (FFQ), from which polyphenol intakes were calculated. Energy-adjusted total polyphenols and subclasses were categorized in tertiles of changes. Linear mixed-effect models with random intercepts (the recruitment centers) were used to assess associations between changes in polyphenol subclasses intake and 1-year plasma glucose or glycosylated hemoglobin (HbA1c) levels. Increments in total polyphenol intake and some classes were inversely associated with better glucose levels and HbA1c after one year of follow-up. These associations were modified when the analyses were run considering diabetes status separately. To our knowledge, this is the first study to assess the relationship between changes in the intake of all polyphenolic groups and T2D-related parameters in a senior population with T2D or at high-risk of developing T2D

    Agroforesterie et services écosystémiques en zone tropicale

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    Respectueux de l’environnement et garantissant une sécurité alimentaire soutenue par la diversification des productions et des revenus qu’ils procurent, les systèmes agroforestiers apparaissent comme un modèle prometteur d’agriculture durable dans les pays du Sud les plus vulnérables aux changements globaux. Cependant, ces systèmes agroforestiers ne peuvent être optimisés qu’à condition de mieux comprendre et de mieux maîtriser les facteurs de leurs productions. L’ouvrage présente un ensemble de connaissances récentes sur les mécanismes biophysiques et socio-économiques qui sous-tendent le fonctionnement et la dynamique des systèmes agroforestiers. Il concerne, d’une part les systèmes agroforestiers à base de cultures pérennes, telles que cacaoyers et caféiers, de régions tropicales humides en Amérique du Sud, en Afrique de l’Est et du Centre, d’autre part les parcs arborés et arbustifs à base de cultures vivrières, principalement de céréales, de la région semi-aride subsaharienne d’Afrique de l’Ouest. Il synthétise les dernières avancées acquises grâce à plusieurs projets associant le Cirad, l’IRD et leurs partenaires du Sud qui ont été conduits entre 2012 et 2016 dans ces régions. L’ensemble de ces projets s’articulent autour des dynamiques des systèmes agroforestiers et des compromis entre les services de production et les autres services socio-écosystémiques que ces systèmes fournissent

    Non-orthogonal unicast and broadcast transmission via joint beamforming and LDM in cellular networks

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    Research efforts to incorporate multicast and broadcast transmission into the cellular network architecture are gaining momentum, particularly for multimedia streaming applications. Layered division multiplexing (LDM), a form of nonorthogonal multiple access (NOMA), can potentially improve unicast throughput and broadcast coverage with respect to traditional orthogonal frequency division multiplexing (FDM) or time division multiplexing (TDM), by simultaneously using the same frequency and time resources for multiple unicast or broadcast transmissions. In this paper, the performance of LDM-based unicast and broadcast transmission in a cellular network is studied by assuming a single frequency network (SFN) operation for the broadcast layer, while allowing for arbitrarily clustered cooperation for the transmission of unicast data streams. Beamforming and power allocation between unicast and broadcast layers, and hence the so-called injection level in the LDM literature, are optimized with the aim of minimizing the sum-power under constraints on the user-specific unicast rates and on the common broadcast rate. The problem is tackled by means of successive convex approximation (SCA) techniques, as well as through the calculation of performance upper bounds by means of semidefinite relaxation (SDR). Numerical results are provided to compare the orthogonal and non-orthogonal multiplexing of broadcast and unicast traffic

    Intra-burst layer aware FEC for scalable video coding delivery in DVB-H

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    This paper investigates how Scalable Video Coding (SVC) can benefit from different Forward Error Correction (FEC) and transmission schemes in mobile broadcast systems. Simulation are performed in DVB-H (Digital Video Broadcasting - Handheld) systems. In DVB-H, a differentiation in robustness for the different SVC layers can be achieved at the link layer using intra-burst MPE-FEC (multi-Protocol Encapsulation FEC). The paper evaluates the gain that can be achieved with the MPE-FEC using equal (EEP) and unequal error protection (UEP), and the performance improvements of an SVC layer-aware FEC (LA-FEC) approach that can be implemented in DVB-H either at the link layer with MPE-iFEC (inter-burst MPE-FEC) or at the application layer with AL-FEC. LA-FEC improves the SVC base layer robustness generating parity information across existing dependencies within the SVC video coding structure. Laboratory measurement results using a TU6 channel model show that the performance of an SVC service in DVB-H can be significantly increased by a proper link layer FEC scheme. It is shown that using SVC in combination with LA-FEC and a proper transmission scheduling does not only give a better performance in terms of PSNR and amount of video outages compared to a single layer service at the same service bit rate, but also gives an additional lower quality layer which can be used for applications like conditional access
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