Mejora de la Arquitectura de Acceso Radio UMTS mediante Multinodos B

Dada la creciente demanda de servicios multimedia en movilidad, las operadoras de telefonía móvil necesitan aumentar constantemente la capacidad de sus sistemas. En ocasiones la única solución posible para mejorar las prestaciones del sistema es incrementar el número de transmisores, siendo ésta una solución costosa. Además, en UMTS utilizar más emplazamientos macro-celulares no siempre garantiza una mayor capacidad del sistema, por los grandes problemas de interferencia mutua que sufren dos macro-celdas si se encuentran demasiado próximas. La única solución que se puede adoptar en estos casos es hacer uso de redes jerárquicas celulares, añadiendo micro-celdas que utilicen una frecuencia de portadora distinta. Esta Tesis Doctoral aporta una visión complementaria al despliegue de las redes jerárquicas y propone aprovechar dicho despliegue para modificar las redes de acceso radio UMTS con nueva arquitectura de nodos B múltiples o Multinodo B. El sistema a desarrollar utiliza la tecnología de nodos B UMTS a los que se conectan un número de antenas distribuidas en diferentes puntos del área de servicio, conformando el equivalente a un array distribuido espacialmente. La incorporación de técnicas de procesado en array junto con mecanismos de gestión dinámica de recursos y la tecnología de enlaces ópticos proporcionarán a este sistema una estructura de acceso radio óptima en entornos micro-celulares y en interiores, con gran flexibilidad y adaptabilidad. Las ventajas de utilizar esta configuración, que se detallan a lo largo de la Tesis Doctoral, son fundamentalmente la mejora de la capacidad de la red de acceso, minimización del impacto radioeléctrico y óptima gestión de recursos. En primer lugar, en esta Tesis Doctoral se demuestra que la nueva arquitectura radio es capaz de dotar al sistema UMTS de una diversidad espacial adicional, diversidad que mejorará los requerimientos de potencia recibida en los terminales, sobre todo en los escenarios micro-celulares. RespectoMonserrat Del Río, JF. (2007). Mejora de la Arquitectura de Acceso Radio UMTS mediante Multinodos B [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1937Palanci

Configurable node density generation with application to hotspot modelling

Mobility models are very relevant mainly when studying the performance of wireless systems by means of computer simulations. The main problem arises when deciding the best mobility model for a particular application. In some cases, it is very important to emulate hotspots or, in general, zones with different user (or node) densities. Current models do not allow complete control over hotspots, or in other words, they do not allow any general node density to be defined in the simulation area. Usually, when hotspots are modelled, closed zones are created with different numbers of users in each area, thus ensuring a fixed node density in each area. However, this approach results in an unfair comparison among users since they cannot move across zones. This paper proposes a new mechanism to solve these drawbacks. Using this mechanism, any general node density can be emulated allowing nodes to move around the entire simulation area. Any mobility model can be applied together with this density control mechanism, provided that the mobility model ensures a uniform node distribution. © 2010 Elsevier Ltd.This work has been funded by the Spanish Ministry of Science and Innovation under project TEC2008-06817-C02-01/TEC.Calabuig Soler, D.; Monserrat Del Río, JF.; Cardona Marcet, N. (2011). Configurable node density generation with application to hotspot modelling. Mathematical and Computer Modelling. 53(11-12):2229-2237. https://doi.org/10.1016/j.mcm.2010.08.028S222922375311-1

5th Generation mobile networks: a new opportunity for the convergence of mobile broadband and broadcast services

© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, 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 component of this work in other works.[EN] This article analyzes the challenges and opportunities that the upcoming definition of future 5G mobile networks brings to the mobile broadband and broadcast industries to form a single converged network. It reviews the state-of-the-art in mobile and broadcast technologies and the current trends for convergence between both industries. This article describes the requirements and functionalities that the future 5G must address in order to make an efficient and flexible cellular-broadcasting convergence. Both industries would benefit from this convergence by exploiting synergies and enabling an optimum use of spectrum based on coordinated spectrum sharing.The authors would like to thank the funding received from the Spanish Ministry of Science and Innovation within the Project number TEC2011-27723-C02-02.Calabuig Gaspar, J.; Monserrat Del Río, JF.; Gómez Barquero, D. (2015). 5th Generation mobile networks: a new opportunity for the convergence of mobile broadband and broadcast services. IEEE Communications Magazine. 53(2):198-205. https://doi.org/10.1109/MCOM.2015.7045409S19820553

Fairness-Driven Fast Resource Allocation for Interference-Free Heterogeneous Networks

Resource allocation in heterogeneous wireless networks is a complex problem. This letter addresses this problem maximizing the sum of logarithms of received rates. From this function, and using the Karush-Kuhn-Tucker (KKT) conditions, this paper proposes an iterative algorithm for allocating resources, which is much faster than conventional techniques. This fast response can be used to optimize larger regions, getting closer to the performance of global and centralized algorithms. © 2012 IEEE.This work was supported by a Marie Curie International Outgoing Fellowship of the European Commission under the project COMIC.Calabuig Soler, D.; Monserrat Del Río, JF.; Cardona Marcet, N. (2012). Fairness-Driven Fast Resource Allocation for Interference-Free Heterogeneous Networks. IEEE Communications Letters. 16(7):1092-1095. doi:10.1109/LCOMM.2012.051512.120720S1092109516

Safety on the roads: LTE alternatives for sending ITS messages

© © 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, 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 component of this work in other works.This article discusses different alternatives for sending intelligent transportation systems (ITS) messages using long-term evolution (LTE) networks. Specifically, it compares the unicast and evolved Multimedia Broadcast Multicast Services (eMBMS) transmission modes by means of system-level simulations and a cost modeling analysis. The optimum configuration of the eMBMS carrier is studied for the case of ITS services. This article also includes some recommendations on the configuration of the ITS server in charge of distributing safety messages as well as on its interaction with the mobile network operator (MNO). The results show that eMBMS is significantly more efficient in terms of resource consumption than the unicast mode, implying an important reduction of the delivery costs.Calabuig Gaspar, J.; Monserrat Del Río, JF.; Gozálvez, D.; Klemp, O. (2014). Safety on the roads: LTE alternatives for sending ITS messages. IEEE Vehicular Technology Magazine. 9(4):61-70. doi:10.1109/MVT.2014.2362272S61709

D1.1 Refined scenarios and requirements, consolidated use cases, and qualitative techno-economic feasibility assessment

This document describes scenarios, consolidated use cases and associated requirements for wireless access networks in the 2020-2030 timeframe. These are based on METIS project and also taking into account work done in other 5G projects and forums such as ITU-R and NGMN. The document introduces spectrum authorization modes and describes spectrum usages scenarios, spectrum bands and spectrum demand for 5G services. Finally, this document provides qualitative techno-economic feasibility assessment by analyzing main players involved in service delivery, from the radio access network point of view, and describing their mutual positions and relationships.Monserrat Del Río, JF.; Martín-Sacristán Gandía, D. (2016). D1.1 Refined scenarios and requirements, consolidated use cases, and qualitative techno-economic feasibility assessment. https://doi.org/10.13140/RG.2.2.32091.7760

5G Spectrum: enabling the future mobile landscape

© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, 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 component of this work in other works.The arrival of the fifth generation (5G) is expected to come together with three important enablers. First, the densification of access nodes will continue. Second, 5G networks must be highly flexible and adapt to the dynamism of the traffic location and patterns. For this, some of the radio access network (RAN) functionalities will run in large computer centers, able to dynamically assign more or fewer units of computation to the virtual cells distributed in the network. Finally, a complex landscape of spectrum availability and access will emerge where multiple frequency bands, subject to different regulations including various forms of shared spectrum, are expected to be available to wireless communication systems.Schotten, HD.; Uusitalo, MA.; Monserrat Del Río, JF.; Queseth, O. (2015). 5G Spectrum: enabling the future mobile landscape. IEEE Communications Magazine. 53(7):16-17. doi:10.1109/MCOM.2015.7158260S161753

Localization in Wireless Networks: The Potential of Triangulation Techniques

User localization is one of the key service-enablers in broadband mobile communications. Moreover, from a different point of view, next steps towards automatic network optimization also depend upon the capability of the system to perform real-time user localization, in order to obtain the traffic distribution. The aim of this paper is to get deeper into the feasibility and accuracy of different localization mechanisms ranging from triangulation to database correlation. Call tracing data extracted from a real operating mobile network have been used to assess these algorithms after the execution of an extensive measurements campaign. Results show that enhanced triangulation offers the best performance even outperforming other more sophisticated mechanisms like fingerprinting, without introducing any change in the network and without requiring any special characteristic of the user equipment. Indeed, the lack of precision of channel estimates, which for the same position could differ up to 10 dB, introduces a large uncertainty that harms localization mechanisms based on database correlation. Finally, this paper identifies the areas for improvement in triangulation to reach its maximum potential, provides details for its implementation and analyzes the performance of the different proposed enhancements. © 2012 Springer Science+Business Media, LLC.The authors would like to thank the funding received from the Ministerio de Industria, Turismo y Comercio within the Project number TSI-020100-2010-183 and from the Generalitat Valenciana IMIDTA/2010/800 funds.Osa Ginés, V.; Matamales Casañ, J.; Monserrat Del Río, JF.; López Bayo, J. (2013). Localization in Wireless Networks: The Potential of Triangulation Techniques. Wireless Personal Communications. 68(4):1525-1538. https://doi.org/10.1007/s11277-012-0537-2S15251538684Laiho J., Wacker A., Novosad T. (2006) Radio Network Planning and Optimisation for UMTS 2nd Edn. Wiley, AmsterdamOsa V., Matamales J., Monserrat J. et al (2010) Expert systems for the automatic optimisation of 3G networks. WAVES 2: 97–105Gustafsson F., Gunnarsson F. (2005) Mobile positioning using wireless networks: Possibilites and fundamental limitations based on available wireless network measurements. IEEE Signal Processing Magazine 22(4): 41–53. doi: 10.1109/MSP.2005.1458284Gezici S. (2008) A survey on wireless position estimation. Springer Wireless Personal Communications 44(3): 263–282. doi: 10.1007/s11277-007-9375-zBahillo, A., Mazuelas, S., & Lorenzo, R.M., et al. (2010). Accurate and integrated localization system for indoor environments based on IEEE 802.11 round-trip time measurements.EURASIP Journal on Wireless Communications and Networking, 2010, Article ID 102095, p. 13. doi: 10.1155/2010/102095 .Yang Z., Liu Y. (2010) Quality of trilateration: Confidence-based iterative localization. IEEE Transactions on Parallel and Distributed Systems 21(5): 631–640. doi: 10.1109/TPDS.2009.90Zimmermann, D., et al. (2004). Database correlation for positioning of mobile terminals in cellular networks using wave propagation models. In IEEE 60th Vehicular Technology Conference (Vol. 7, pp. 4682–4686) doi: 10.1109/VETECF.2004.1404980 .Zhao Y. (2002) Standardization of mobile phone positioning for 3G systems. IEEE Communications Magazine 40(7): 108–116. doi: 10.1109/MCOM.2002.1018015Caffery J.J., Stuber G.L. (1998) Overview of radiolocation in CDMA cellular systems. IEEE Communications Magazine 36(4): 38–45. doi: 10.1109/35.667411Kaaranen H., Ahtiainen A., Laitinen L., Naghian S., Niemi V. (2005) UMTS networks: Architecture, mobility and services. Wiley, Amsterdam3GPP. (2010). TS 25.215 Physical layer; Measurements (FDD). http://www.3gpp.org/ftp/Specs/archive/25_series/25.215/25215-920.zip .3GPP. (2010). TS 25.133 Requirements for support of radio resource management. http://www.3gpp.org/ftp/Specs/archive/25_series/25.133/25133-950.zip .3GPP. (2009). TS 45.010 Radio subsystem synchronization. http://www.3gpp.org/ftp/Specs/archive/45_series/45.010/45010-900.zip .Kos, T., Grgic, M., & Sisul, G. (2006). Mobile user positioning in GSM/UMTS cellular networks. In 48th International Symposium ELMAR-2006 focused on multimedia signal processing and communications (pp. 185–188). doi: 10.1109/ELMAR.2006.329545 .Kirkpatrick S., Gelatt C. D. Jr., Vecchi M. P. (1983) Optimization by simulated annealing. Science 220(4598): 671–680. doi: 10.1126/science.220.4598.671Hepsaydir, E. (1999). Analysis of mobile positioning measurements in CDMA cellular networks. In Radio and Wireless Conference, RAWCON 99 (pp. 73–76). doi: 10.1109/RAWCON.1999.810933 .Villebrun, E., Ben Hadj Alaya, A., Boursier, Y., & Noisette, N. (2006). Indoor Outdoor user discrimination in mobile wireless networks. In Vehicular Technology Conference 2006 Fall (pp. 1–5, 25–28). doi: 10.1109/VTCF.2006.500 .Farr, T.G., et al. (2007). The shuttle radar topography mission. Reviews of geophysics, Vol. 45, RG2004, 33 pp. doi: 10.1029/2005RG000183

Multi-user non-coherent detection for downlink MIMO communication

© 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, 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 component of this work in other works.[EN] Current cellular technologies are based on the concept of coherent communication, in which the channel matrix used for demodulation is estimated via reference or pilot signals. Coherent systems, however, involve a significant increase of the signalling overhead, especially when the number of transmission points is increased or when the mobile channel changes rapidly, which motivates the use of non-coherent techniques. This letter extends the use of non-coherent communications to a multi-user (MU) multiple-input multiple-output (MIMO) framework by combining superposition coding with a reduced-complexity detection method. Numerical results confirm that our scheme achieves higher user rates than non-coherent MU transmission based on time multiplexing. In addition to the well-known sum-rate gain of MU systems, an extra performance gain given by downlink non-coherent MU communication is shown and qualitatively justified.This work was performed in the framework of the FP7 project ICT-317669 METIS, supported in part by the European Union. The authors would like to acknowledge the contributions of their colleagues in METIS, although the views expressed are those of the authors and do not necessarily represent the project. The associate editor coordinating the review of this manuscript and approving it for publication was Prof. Chandra Ramabhadra Murthy.Roger Varea, S.; Calabuig Soler, D.; Cabrejas Peñuelas, J.; Monserrat Del Río, JF. (2014). Multi-user non-coherent detection for downlink MIMO communication. IEEE Signal Processing Letters. 21(10):1225-1229. https://doi.org/10.1109/LSP.2014.2330854S12251229211

Aula Inversa: una oportunidad para el desarrollo de competencias transversales

[EN] A preliminary work about the impact of the Flipped Classroom (FC) in the development of different Soft Skills (SS) defined by the UPV is shown in this article. Throughout the 2015-16 academic year, some particular subjects in the Universitat Politècnica de València (UPV) are checkpoints to monitor the implementation and assessment of the specific SS. All SS must be developed every year and their control is distributed for assessment in the different courses to ensure a complete evaluation of the SS is offered at the several training stages students. The professors belonging to the MATI EICE group have previous experience in making digital materials and using them in the FC methodology. Also, due to the fact that we are a multidisciplinary group, each member has assessed the SS for which their subjects were control points, which enriches this study, offering a broad overview regarding the possibilities to use FC in the classroom to work the skills the students must have at the end of their education.[ES] En este trabajo se presenta un estudio preliminar del impacto de la técnica de Aula Inversa (AI) en el desarrollo de diferentes Competencias Transversales (CT). En el curso 15-16 todas las asignaturas son puntos de control en el desarrollo de alguna de las CT que define la Universitat Politècnica de València (UPV). Todas las CT han de ser desarrolladas en todos los cursos del grado y han de ser evaluadas en las distintas asignaturas con el fin de ofrecer una evaluación completa de competencias en distintas etapas de la formación de cada estudiante. Nuestro grupo EICE de profesores (MATI) tiene experiencia previa en la preparación de materiales digitales y su aplicación con la técnica de Aula Inversa. Al ser un grupo multidisciplinar a cada miembro del grupo le corresponde evaluar una competencia distinta, lo cual enriquece el estudio, ofreciendo una visión bastante amplia acerca de las posibilidades de aplicación.Fita Fernández, IC.; Monserrat Del Río, JF.; Moltó Martínez, G. (2016). Aula Inversa: una oportunidad para el desarrollo de competencias transversales. En In-Red 2016. II Congreso nacional de innovación educativa y docencia en red. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2016.2016.4364OC