16 research outputs found

    Millimeter-wave Wireless LAN and its Extension toward 5G Heterogeneous Networks

    Full text link
    Millimeter-wave (mmw) frequency bands, especially 60 GHz unlicensed band, are considered as a promising solution for gigabit short range wireless communication systems. IEEE standard 802.11ad, also known as WiGig, is standardized for the usage of the 60 GHz unlicensed band for wireless local area networks (WLANs). By using this mmw WLAN, multi-Gbps rate can be achieved to support bandwidth-intensive multimedia applications. Exhaustive search along with beamforming (BF) is usually used to overcome 60 GHz channel propagation loss and accomplish data transmissions in such mmw WLANs. Because of its short range transmission with a high susceptibility to path blocking, multiple number of mmw access points (APs) should be used to fully cover a typical target environment for future high capacity multi-Gbps WLANs. Therefore, coordination among mmw APs is highly needed to overcome packet collisions resulting from un-coordinated exhaustive search BF and to increase the total capacity of mmw WLANs. In this paper, we firstly give the current status of mmw WLANs with our developed WiGig AP prototype. Then, we highlight the great need for coordinated transmissions among mmw APs as a key enabler for future high capacity mmw WLANs. Two different types of coordinated mmw WLAN architecture are introduced. One is the distributed antenna type architecture to realize centralized coordination, while the other is an autonomous coordination with the assistance of legacy Wi-Fi signaling. Moreover, two heterogeneous network (HetNet) architectures are also introduced to efficiently extend the coordinated mmw WLANs to be used for future 5th Generation (5G) cellular networks.Comment: 18 pages, 24 figures, accepted, invited paper

    System Level Design of Software-Defined Radio Platform

    Get PDF
    This major qualifying project proposes a new single-board design for a Dedicated Short Range Communication (DSRC) On Board Unit (OBU) which consists of a Zynq 7030 system on a chip and AD9361 wideband transceiver. This software-defined radio (SDR) platform design is based on ZedBoard and FMcomms2. The advantages of this approach compared to the ZedBoard and FMcomms2 joint solution are smaller form factor, front end tuned to 5.9GHz and a more powerful processor. Since the prototype has not been manufactured due to the time constraints of this project, the working implementation of 6GHz DSRC radio 802.11p in GNU Radio has been confirmed on the lower capability hardware USRP2 and USRP N210 (Universal Software Radio Peripheral)

    GigaHertz Symposium 2010

    Get PDF

    2009 Exhibitors

    Get PDF
    Listings and Descriptions of 2009 Small Satellite Conference Exhibitor

    Impacto das comunicações M2M em redes celulares de telecomunicações

    Get PDF
    Mestrado em Engenharia Electrónica e de TelecomunicaçõesAs comunicações Máquina-Máquina (M2M) apresentam um crescimento muito significativo e algumas projeções apontam para que esta tendência se acentue drasticamente ao longo dos próximos anos. O tráfego gerado por este tipo de comunicações tem caraterísticas muito diferentes do tráfego de dados, ou voz, que atualmente circula nas redes celulares de telecomunicações. Assim, é fundamental estudar as caraterísticas dos tipos de tráfego associados com comunicações M2M, por forma a compreender os efeitos que tais caraterísticas podem provocar nas redes celulares de telecomunicações. Esta dissertação procura identificar e estudar algumas das caraterísticas do tráfego M2M, com especial enfoque na sinalização gerada por serviços M2M. Como resultado principal deste trabalho surge o desenvolvimento de modelos que permitem a construção de uma ferramenta analítica de orquestração de serviços e análise de rede. Esta ferramenta permite orquestrar serviços e modelar padrões de tráfego numa rede UMTS, possibilitando uma análise simultânea aos efeitos produzidos no segmento core da mesma rede. Ao longo deste trabalho procura-se que a abordagem aos problemas apresentados permita que os resultados obtidos sejam válidos, ou adaptáveis, num âmbito mais abrangente do que apenas as comunicações M2M.Machine to Machine (M2M) communications present significant growth and some projections indicate that this trend is going to increase dramatically over the coming years. The traffic generated by this type of communication has very different characteristics when compared to data or voice traffic currently going through cellular telecommunications networks. Thus, it is essential to study the characteristics of traffic associated with M2M communications in order to understand the effects that its features can imply to cellular telecommunications networks. This dissertation tries to identify and study some of the characteristics of M2M traffic, with particular focus on signaling generated by M2M services. A number of models, that enable the development of an analytic tool for service orchestration and network analysis, are presented. This tool enables service orchestration and traffic modeling on a UMTS network, with simultaneous visualization of the impacts on the core of such network. The work presented in this document seeks to approach the problems at study in ways ensuring that its outcomes are valid for a wider scope than just M2M communications

    Analysis and design of an 80 Gbit/sec clock and data recovery prototype

    Get PDF
    La demande croissante de toujours plus de débit pour les télécommunications entraine une augmentation de la fréquence de fonctionnement des liaisons séries. Cette demande se retrouve aussi dans les systèmes embarqués du fait de l'augmentation des performances des composants et périphériques. Afin de s'assurer que le train de données est bien réceptionné, un circuit de restitution d'horloge et de données est placé avant tout traitement du coté du récepteur. Dans ce contexte, les activités de recherche présentées dans cette thèse se concentrent sur la conception d'une CDR (Clock and Data Recovery). Nous détaillerons le comparateur de phase qui joue un rôle critique dans un tel système. Cette thèse présente un comparateur de phase ayant comme avantage d'avoir une mode de fenêtrage et une fréquence de fonctionnement réduite. La topologie spéciale utilisée pour la CDR est décrite, et la théorie relative aux oscillateurs verrouillés en injection est expliquée. L'essentiel du travail de recherche s'est concentrée sur la conception et le layout d'une restitution d'horloge dans le domaine millimétrique, à 80 Gbps. Pour cela plusieurs prototypes ont été réalisés en technologie BiCMOS 130 nm de STMicrolectronics.The increasing bandwidth demand for telecommunication leads to an important rise of serial link operating frequencies. This demand is also present in embedded systems with the growth of devices and peripherals performances. To ensure the data stream is well recovered, a clock and data recovery (CDR) circuit is placed before any logical blocks on the receiver side. The research activities presented in this thesis are related to the design of such a CDR. The phase detector plays a critical role in the CDR circuit and is specially studied. This thesis presents a phase comparator that provides an enhancement by introducing a windowed mode and reducing its operating frequency. The used CDR has a special topology, which is described, and the injection locked oscillator theory is explained. Most of the research of this study has focused on the design and layout of a 80 Gbps CDR. Several prototypes are realized in 130 nm SiGe process from STMicroelectronics.BORDEAUX1-Bib.electronique (335229901) / SudocSudocFranceF

    High-speed, low cost test platform using FPGA technology

    Get PDF
    The object of this research is to develop a low-cost, adaptable testing platform for multi-GHz digital applications, with concentration on the test requirement of advanced devices. Since most advanced ATEs are very expensive, this equipment is not always available for testing cost-sensitive devices. The approach is to use recently-introduced advanced FPGAs for the core logic of the testing platform, thereby allowing for a low-cost, low power-consumption, high-performance, and adaptable test system. Furthermore to customize the testing system for specific applications, we implemented multiple extension testing modules base on this platform. With these extension modules, new functions can be added easily and the test system can be upgraded with specific features required for other testing purposes. The applications of this platform can help those digital devices to be delivered into market with shorter time, lower cost and help the development of the whole industry.Ph.D

    Advanced devices based on fibers, integrated optics and liquid crystals for WDM networks

    Get PDF
    The increment of bandwidth required for new services offered to users make necessary the use of optical fibres in data transmission. Glass optical fibres are widely used in long distance communications, and there are many devices implemented for using in these networks, but these technologies are sometimes expensive for their used in local loops. Different systems implemented over the established technology are used for increasing local loops bandwidth, but more services are demanded at home. Those applications require more bandwidth than the offered by the usual twisted copper pair. Multimode fibres (both silica and polymer) with larger core diameters and numerical aperture, allows for large tolerance on axial misalignments, which results in cheaper connectors as well as associated equipment, but with a bandwidth penalty with regards to their singlemode counterparts, mainly due to the introduction of modal dispersion. On the other hand, polymer optical fibre (POF) offers several advantages over conventional multimode optical fibre over short distances (ranging from 100m to 1000m) such as the even potential lower cost associated with its easiness of installation, splicing and connecting. This is due to the fact that POF is more flexible and ductile, making it easier to handle. Consequently, POF termination can be realized faster and cheaper than in the case of multimode silica fibre. Therefore, the number of applications that use POF is quickly increasing. POF is being used in video transmission in medical equipment, or in multimedia applications for civil aviation and high range cars, in-home and access networks, wireless LAN backbone or office LAN, and in intrinsic optical sensor networks among others. Even greater channel capacity can be available using a specific type of POF, perfluorinated Graded-Index POF (PF GIPOF), having low attenuation and large bandwidth from 650nm to 1300nm. Link lengths for in-building/home scenarios are short (less than 1 km), and thus the loss per unit length is of less importance. Transmission of 10Gbps data over 100m and transmission of 1.25Gbps Ethernet over 1 km have been experimentally demonstrated with PF GIPOF. On the other hand, combiners and multiplexers are basic elements in POF networks using Wavelength Division Multiplexing (WDM) and there are not that many already developed. It is important to have low losses devices and reconfiguration can be an additional feature in those networks. On the other hand, reconfigurable optical networks in critical applications demand devices able to have different functionalities, including switching. This work has focused in the development of different optical switches for a wide range of optical networks. Different switching technologies are available. Liquid crystals are widely used as displays, but they are also employed in telecommunications. Other common technology used in data routing is integrated optics. In this case, light propagates by means of a waveguide and the modification of its parameters makes possible switching operation. Micro-Electromechanical Mechanisms, MEMs, based in small mobile mirrors that can change the direction of the incident light when required are an important optical switching technology. The objective of the present work is the proposal of several optical switches using different technologies depending on the final application. Some of these structures have been experimentally tested whereas others have been simulated. Most of the presented switches use liquid crystals, having different functionalities and broadband operation range, so allowing wavelength division multiplexing. To these respect it has been developed an optical multiplexer/combiner and an advanced multifunctional optical switch (AMOS), both implemented with Nematic Liquid Crystal technology. It has also been developed a multiplexer/combiner based on Polymer Dispersed Liquid Crystals. The third kind of switches proposed are micro ring-resonators combined with liquid crystals. Micro ring-resonators consist of a circular waveguide attached to one or two straight waveguides acting like input and output ports. Light that passes through the structure can be filtered according to the ring resonator characteristics: ring length, coupling ratio, losses… The use of liquid crystal makes possible the tuning of the ring resonator filtering properties. The last proposed switch is made of a passive splitter and a Mach-Zehnder Interferometer. This kind of devices makes use of integrated optics and interference for switching purposes. The variation of the optical properties influencing the two light beam interference can be done in different ways: thermally, electrically… Finally, an automated optical characterization bench has been implemented in order to make easy the measurements. It is composed by a three axis translation stage with three actuators, several linear translation stages that allows the user to modify the bench structure for adapting it to his experiment, and different machinery for mounting the optics.The present research work has been supported by the following Spanish projects: TIC2003-038783 (DISFOTON), TEC2006-13273-C03-03-MIC (FOTOCOMIN) and TEC2009-14718-C03-03-MCI (DEDOS) of the Spanish Interministerial Commission on Science and Technology (CICYT), FACTOTEM-CM: S-005/ESP/000417, and FACTOTEM-II-CM: S2009/ESP-1781 and FENIS-CCG06-UC3M/TIC-619 of Comunidad Autónoma de Madrid. Additional financial support has been obtained form European Thematic Network SAMPA: Synclinic and Anticlinic Mesophases for Photonic Applications (HPRNCT- 2002-00202), carried out during the V Framework Program of the European Union, COST Action 299 FIDES: Optical Fibres Dedicated to Society, and from the European Network of Excellence: ePhoton/ONe+ (FP6-IST-027497), both carried out during the VI Framework Program of the European Union, and BONE: Building the Future Optical Network in Europe (FP7-ICT-216863) carried out during the VII Framework Program of the European Union

    Topical Workshop on Electronics for Particle Physics

    Get PDF
    The purpose of the workshop was to present results and original concepts for electronics research and development relevant to particle physics experiments as well as accelerator and beam instrumentation at future facilities; to review the status of electronics for the LHC experiments; to identify and encourage common efforts for the development of electronics; and to promote information exchange and collaboration in the relevant engineering and physics communities
    corecore