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Invited Presentations
Optical Data Bus Technologies for Automotive Applications
O. Strobel, Esslingen University of Applied Sciences and
MB-technology GmbH, Stuttgart, Germany
Abstract
This paper deals with state of the art and next-decade technologies for optical data buses in automotive applications. Nowadays, optical data buses in automotive applications are almost exclusively used in the infotainment domain, MOST (Media Oriented System Transport). Current data rates are in the order of 20 MBit/s. Consequently, the use of LEDs and polymer optical fibers (POF) is sufficient. The next generation of these optical buses has to operate at about 150 MBit/s. Therefore, the LED/POF solution has reached the uttermost limit of operation. For higher data rates, alternative solutions have to be found: The LED as transmitter has to be replaced by a vertical surface emitting laser (VCSEL), and plastic fiber (POF) will have to be substituted by polymer-cladded silica (PCS) fiber. Due to the inherent fact that, as a result, the fiber diameter is reduced, the detector area of the well-known Silicon photo diodes can also be reduced greatly. As a consequence, data rates can be extended into the Gbit/s-region. This situation then enables us to use the system for sensor applications as well, including safety-relevant operations like drive by wire, break by wire and engine management, and may at last lead in the coming decades to autonomous driving.
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Secure Communications: The Infrared Alternative
R. J. Green, School of Engineering, University of Warwick, UK
Abstract
Much of the world's high-speed communications travel through optical fibres, and a rapidly-increasing demand for network bandwidth to accommodate both data and voice traffic has developed. There is a bottleneck n the access network to enable delivery of multimedia services to residential and small business customers. Coupled with this is a rapidly-growing demand for mobility via wireless technologies, driven by expansion in the use of PDAs and mobile telephones. The ubiquitous nature of computer terminals in the modern office also means that a wireless network, devoid of the inconvenience and cost of reconfiguring wired systems, is increasingly appealing (communications "anytime, anywhere"). The use of infrared communications through free space, or optical wireless, is very promising, as a means of supporting the high bit rates which will be required by future multimedia services, since it offers potentially large unregulated bandwidths.
Recently there has been increased recognition of the advantages of the optical portion of the spectrum when compared to radio as a medium for short-range communication. This, coupled with technological advances such as the Warwick optical antenna, has produced a growth in interest in optical wireless systems for both in indoor and outdoor applications. In particular, optical wireless offers high bandwidth at low-cost, immunity to radio interference, an unregulated spectrum and small components that consume little power. This paper reviews optical wireless, and shows how it is developing and permitting unprecedented free spectrum, secure, immune from the effects of any other RF communications, and internationally unlicensed.
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Multimedia need more bandwidth – may Internet collapse?
Z. Kadzielski, National Institute of Telecommunications, Poland
Abstract
The paper covers new requirements on bandwidths in new multimedia services over IP networks with the mixture of transmission technologies. With the exponentially growing traffic volume current network infrastructure is not designed to fulfill those requirements. Internet may not withstands expectations due to visible bottlenecks in access and switching areas. It is presented how the infrastructure should be changed to overcome those weaknesses. It is shown that the possible solution is optical switching.
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Survivable Wavelength-Routed Optical Network Design Using Genetic Algorithms
M. S. Leeson1, Y. S. Kavian 2, W. Ren 1, E. L. Hines 1, H. F. Rashvand 1 and M. Naderi 2
1School of Engineering, University of Warwick, Coventry, CV4 7AL, UK
2Iran University of Science and Technology (IUST), 16844, Tehran, Iran
Abstract
The provision of acceptable service in the presence of failures and attacks is a major issue in the design of next generation Dense Wavelength Division Multiplexing (DWDM) networks. This is particularly true if they are to be employed as backbones for the provision of future IP services with enhanced QoS. Survivability is provided by the establishment of redundant lightpaths for each connection request to protect the primary lightpaths. This paper presents a genetic algorithm (GA) solver for the routing and wavelength assignment problem with working and spare lightpaths. Lightpaths are encoded into variable length binary strings based on the shortest eligible paths between each origin-destination pair. The GA finds the two best disjoint origin to destination paths and assigns the minimum number of wavelengths to them according to the problem constraints. The proposed approach has been evaluated on both dedicated path protection and shared path protection. Simulation results show that the GA method is efficient and able to design DWDM survivable real-world optical mesh networks.
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Quality of Service of Internet Service Provider Networks:
state of art and new trends
A. Toguyéni, and O. Korbaa, University of Lille, France
Abstract
These ten last years, the emergences of new applications through Internet such as multimedia applications (VoIP, video broadcasting …) or networked control applications, users need more and more quality of service (QoS) when using Internet. However, the requested QoS is not the same depending on the application. Some of them request a lot of bandwidth like video broadcasting others need short guaranteed delays …
Several new models, to manage internet traffic, have been proposed. Most of them focus on specific QoS criteria they want to optimize. This paper focuses on approaches based on MPLS that are more adapted to the configuration of ISP networks. The article first introduces the different mechanisms that can be used to improve the QoS of a network such as the models of traffic classification (IntServ or DiffServ) or multipath routing. The second part justifies the choice of MPLS technology versus a simple use of IP. After that, the paper presents main MPLS approaches such as MATE, LDM or WDP that try to guaranty a certain quality with respect to specific criteria. In the last part, it presents new models such as LBWDP and PEMS that try to adapt the offered quality depending on the type of the routed traffic.
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Modulation Techniques for Wireless Infrared Communication Links – A Review
F. Z. Ghassemlooy, W.O. Popoola, S. Rajbhandari, M. Amiri, S. Hashemi
Northumbria University, Newcastle, UK
Abstract
A number of modulation techniques have been proposed and thoroughly analysed in literature for optical
wireless communication systems. Each modulation technique has its unique attractive features as well as its
challenges. Some are very simple to implement and bandwidth efficient like the On-Off keying (OOK). Pulse
interval modulation (PIM) techniques are reputed for their inherent synchronisation pulse, subcarrier modulation offers increased throughput, resilience to the inter-symbol interference (ISI) and immunity against the fluorescent-light noise near DC, while pulse position modulation (PPM) provides the unparalleled power efficiency in line of sight (LOS) links but the performance degrades severely in dispersed communication
channel. There has been an enormous work on the analysis of these and many more modulation techniques
under different channel and environmental conditions; we however present here a concise synopsis of the mostly
reported wireless infrared modulation techniques.
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Photonic Band Gap Chirped Waveguides for Efficient Signal routing
A. D'Orazio, University of Bari, Italy
Abstract
Recently, new 2D-PC-based demultiplexing configurations have been proposed in literature in order to show how the multi-wavelength drop operation can be accomplished by the connection of different PC regions having different lattice constants, namely the in-plane hetero-photonic crystal (IP-HPC). The heterostructure interfaces between adjacent photonic crystal regions can act as wavelength selective mirrors, so that part of the input light cannot propagate in the subsequent sections: the signal is then reflected back and coupled to high-Q microcavities. The demultiplexing functionality can be also accomplished considering the variation of the air-hole radii of the PC waveguide along the propagation direction of the PBG waveguide as the incident light signal propagates through an input waveguide. In this paper simple and efficient designs of demultiplexing systems in 2D-PC based technology are proposed and discussed.
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Towards Seamless Fiber-Wireless (FiWi) Access Networks:
Convergence and Challenges
S. Aïssa and Martin Maiero
INRS-EMT, University of Quebec, Canada
Abstract
Traditionally, wireless and optical fiber networks have been designed separately from each other. Wireless
networks aimed at meeting specific service requirements while coping with particular transmission impairments
and optimizing the utilization of the system resources to ensure cost-effectiveness and satisfaction for the end user. In optical networks, on the other hand, research efforts rather focused on cost reduction, simplicity, and future-proofness against legacy and emerging services and applications by means of optical transparency. With the ultimate goal of providing access to information when needed, wherever needed, and in whatever format it is needed, the vision of technological convergence of wireless and optical networks is not only becoming a necessity but also plays a key role in future communications networks. Towards the technical evolution of wireless-optical access networks and the seamless coexistence of both technologies, this paper provides a review of state-of-the-art developments and advances in wireless and optical communications, presents key technical challenges for providing seamless communications in fiber-wireless (FiWi) access networks, and highlights the main research issues for providing intelligence, transport, access, and convergence of these future networks.
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Radio over Fiber Access Network Architecture Employing Reflective
Semiconductor Optical Amplifiers
M.C.R. Medeiros1, R. Avó 1, P. Laurêncio 1, N.S. Correia 1, A. Barradas 1, H.J.A. da Silva 2, I. Darwazeh 3, J.E. Mitchell 3 and P.M.N. Monteiro 4
1University of Algarve, Portugal, 2Universidade de Coimbra, Portugal
3University College London, UK, 4University of Aveiro,Portugal
Abstract
This paper introduces the RoFnet-Reconfigurable Radio over Fiber network, which is a project supported by the
Portuguese Foundation for Science and Technology. This project proposes an innovative radio over fiber optical
access network architecture, which combines a low cost Base Station (BS) design, incorporating reflective
semiconductor optical amplifiers, with fiber dispersion mitigation provided by optical single sideband
modulation techniques. Optical wavelength division multiplexing (WDM) techniques are used to simplify the
access network architecture allowing for different Base Stations to be fed by a common fiber. Different
wavelength channels can be allocated to different BSs depending on user requirements. Additionally, in order to improve radio coverage within a cell, it is considered a sectorized antenna interface. The combination of
subcarrier multiplexing (SCM) with WDM, further simplifies the network architecture, by using a specific
wavelength channel to feed an individual BS and different subcarriers to drive the individual antenna sectors
within the BS.
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Integrated Optical Sensor for Environmental Monitoring
M. Bozzetti, G. Calò, A. D’Orazio, M. De Sario, L. Mescia,
V. Petruzzelli, F. Prudenzano, Technical University of Bari, Italy
Abstract
A brief overview on integrated optical sensors for environment monitoring is given. A variety of optical transducers is illustrated and the interaction between the evanescent electromagnetic field and the polluted medium under detection is described in detail. A chemically selective layer on the waveguide core binds and/or absorb the polluting molecules contained in the liquid or gaseous sample. The variation of the real and/or the imaginary part of the sensitive layer refractive index affects the penetration depth of the evanescent field of the core guided waves. Many sensor, based on this principle, configurations have been developed for chemical and biochemical applications. As an example, in this rieview the main numerical results pertaining to integrated optical sensors for hydrocarbon detection in water are illustrated. Various kind of planar waveguide sensors are designed by considering a polydimethylsiloxane (PDMS) polymeric overlay. The waveguide cross-section is refined to enhance the evanescent optical field, which interacts with the surrounding polymeric overlay and effects the waveguide sensor performance. The sensor based on this approach detects changes in the waveguide attenuation constant induced by the penetration of the hydrocarbons into the PDMS. The obtained results show that the proposed sensors could represent good candidates in terms of detection sensitivity and, in addition, to identify different analytes mixed in water solution.
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Investigation on CdS: Mn quantum dots by using scanning laser microscopy
S. G. Stanciu1, R.Hristu1, B. Savu1 and G. A. Stanciu1
D. Mohanta2, G. A. Ahmed2 and A. Choudhury2
1University Polytehnica of Bucharest, Romania,
2 Tezpur University, India
Abstract
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All-optical switching by entangling quantum dot states in a photonic crystal cavity
G. Manzacca1, K. Hingerl2, G. Cincotti1
1University of Roma Tre, Italy,
2 Johannes Kepler University, Austria
Abstract
We analyze the behaviour of a quantum dot embedded in a photonic crystal add-drop filter and in a direct
coupled photonic crystal microcavity for optical signal processing applications. The joint effect of Dipole
Induced Transparency and Electromagnetic Induced Transparency, considering a cascade configuration of the
quantum dot, are used to modify the behaviour of the whole system. The mathematical model and a number of
different conditions for tuning the frequency response of the filters are derived for application in all-optical switching and wavelength tunable devices.
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Telecommunication Trend in the first half of this Century and its Impact on Information Society
H. Khakzar, University of Stuttgart, Germany
Abstract
This paper deals with Telecommunication trends in the next decades. First of all, trends in microelectronics technology as predicted by SIA in their roadmap will be presented. Based on ever shrinking geometries of solid state devices and ever decreasing size of telecommunication equipment, the number of telecommunication subscribers will add up in the next few decades, until in average every man on earth has a mobile phone. The demand for higher bandwidth leads us to the use of optical fibres in networks around the world. This trend also boosts equipment development, as we will see in another part of this paper. Coding will be in future very important. By Telecommunication we get the feeling that we live in a small village. Telecommunication is the most effective vehicle to reduce the gap between industrialised and developing countries.
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The Environmental Influence on behaviour of various structure used in dentistry
I. Demetrescu, University Polytehnica of Bucharest, Romania
Abstract
The aim of the present paper is to put in evidence the environmental influence on behaviour of various structure in dentistry being based on the necessity to be conform to the concept of health& environment. The structures of studied materials are both hard and soft, natural and synthetic and the environment simulated factors are mainly heavy metals and fluoride ions. The used techniques in the paper are related to investigation of composition, structure, morphology, electrochemical properties, and hydrophilic/ hydrophobic balance at interface with environment. With these methods one intend to establish new properties for some dental biomaterials and propose original correlations between the influences of some environmental factors and dental health, as well as some measures and some prophylactic products recommended in the affected areas.
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Design of push-pull chromophores based on the incorporation of
transition metal acetylides in the main Pi–conjugated system
J. Fillaut1, Jérôme Luc2, Bouchta Sahraoui2
1University of Rennes, France, 2University of Angers, France
Abstract
Carbon-rich organometallics containing rigid ð–conjugated chains are important targets for the investigation of push-pull chromophores and materials for linear and non linear applications This approach provides a way
of realizing new materials with improved optical properties including nonlinear properties and formation of
surface-relief gratings (SRGs).
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Reduction of Packet Order Performance Penalty in IBWR Switches
J. Veiga-Gontán, P. Pavón-Mariño, J. García-Haro
Universidad Politécnica de Cartagena, Spain
Abstract
Packet order in slotted Input Buffer Wavelength Routed (IBWR) switches, operating under (i) synchronous
Optical Packet Switching (OPS), (ii) Scattered Wavelength Path (SCWP) operational mode and (iii) fixed packet
size, can be preserved by using a parallel iterative scheduler, as discussed in reference [1]. The performance
achieved is comparable to the ideal output buffering architecture, degrading only for high input loads. The
scheduler in [1] maintains packet order among every input fiber-output fiber pair. In virtual circuit-based
networks, packet order has to be maintained among packets in the same traffic connection. Maintaining packet
sequence among all packets in the same input fiber-output fiber pair is a constraint excessively hard. However, it is commonly used to simplify the scheduler design. This paper studies the performance improvement obtained in the OI-PDBM scheduler, if the ordering constrained is softened, and applied only among packets belonging to the same traffic connection. A GMPLS (Generalized MultiProtocol Label Switching) control plane is assumed, so that packet flow is identified by tagging information stored in packet header. A discussion regarding switch scheduler feasibility is also included.
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Performance comparison of scheduling algorithms for IPTV traffic
over Polymorphous OBS routers
V. López, J. L. García-Dorado, J. A. Hernández, J. Aracil
Universidad Autónoma de Madrid, Spain
Abstract
Recent research in Optical Burst Switched networks has proposed solutions to support subwavelength
reservation for the periodic transmission of data bursts, which can coexist with conventional asynchronous
bursts, bringing the Polymorphous, Agile and Transparent Optical Networks (PATON) [1]. Thus, network
operators can distribute IPTV channels to their customers, whereby they can use the spare bandwidth for the
transmission of best-effort traffic, making use of the free gaps in between such periodic reservations. This work proposes scheduling algorithms for the transmission of periodic channels using PATON, and studies the
blocking probability observed by best-effort traffic, when such scheduling algorithms are used.
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New routes for exploiting the optical properties of artificial opals
J. F. Galisteo-López, Università di Pavia, Italy
Abstract
Artificial opals are nowadays acknowledged as ideal playgrounds where the optical properties of three
dimensional (3D) photonic crystals can be tested. Over the past few years several works have demonstrated that
a strong enhancement of the interaction between light and matter can be achieved with these systems.
These type of nano-structured materials tend to grow in an FCC lattice with the (111) planes parallel to the
sample surface. This characteristic fact imposes some restrictions on their dispersion relation (and hence on its optical properties) which are usually compensated for by introducing modifications in their topology by
infiltrating them with high refractive index materials or introducing controlled defects.
In this work we present recent results regarding the optical characterization of artificial opals containing planar defects as well as opals oriented along crystallographic directions other than the (111). The amplitude and phase of light transmitted through the samples is measured providing us with valuable information regarding the way light propagates in these structures. Our results evidence that besides the well known response in the surroundings of the stop-band, these structures can exhibit much more exciting properties such as superluminal propagation with negative group velocities.
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Convergence between optical wireless and impulse radio UWB in
low data rate applications
L. Nardis, University La Sapienza, Rome, Italy
Abstract
Recent developments in Ultra Wide Band (UWB) technology led to the definition of a new impulse radio UWB-based IEEE standard for low data rate communications, IEEE 802.15.4a. UWB radio is however sensible to strong external interference due to the low emission levels allowed by current regulation. Given the strong similarities between impulse radio UWB and wireless optical, the combination of the two technologies can provide strong benefits and overcome the limitations of the two technologies.
This work proposes a strategy that combines the two physical layer techniques by adopting a common medium access control protocol, and analyzes the performance of the solution under specific application scenarios.
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Tailoring Er3+ spectroscopic properties by nanocomposite
photonic glasses and confined structures
C. Armellini et al., CNR-IFN, Institute of Photonics & Nanotechnology, Italy
Abstract
Paper reports recent advances in optical nanomaterials, planar microcavity, and spherical microresonators.
Bottom-up fabrication and optical assessment of Er3+-activated SiO2-HfO2 waveguide glass ceramic is presented.
Concerning confined structures, fabrication by rf sputtering technique of an Er3+-activated microcavity with a quality factor of 171 using oxide-based dielectric materials is demonstrated and fabrication and spectroscopic assessment of Er3+-activated silica microspheres is presented.
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Load Balanced Distributed Schedulers for WASPNET Optical Packet Switches
Maintaining Packet Order
M. Rodelgo-Lacruz, C. López-Bravo, F. J. González-Castaño
Universidad de Vigo, Spain
Abstract
Recent developments in Ultra Wide Band (UWB) technology led to the definition of a new impulse radio UWB-based IEEE standard for low data rate communications, IEEE 802.15.4a. UWB radio is however sensible to strong external interference due to the low emission levels allowed by current regulation. Given the strong similarities between impulse radio UWB and wireless optical, the combination of the two technologies can provide strong benefits and overcome the limitations of the two technologies.
This work proposes a strategy that combines the two physical layer techniques by adopting a common medium access control protocol, and analyzes the performance of the solution under specific application scenarios.
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Nonlinear Optical Properties of some Au Nanostructures
S. Couris, University of Patras, Greece
Abstract
Recent developments in Ultra Wide Band (UWB) technology led to the definition of a new impulse radio UWB-based IEEE standard for low data rate communications, IEEE 802.15.4a. UWB radio is however sensible to strong external interference due to the low emission levels allowed by current regulation. Given the strong similarities between impulse radio UWB and wireless optical, the combination of the two technologies can provide strong benefits and overcome the limitations of the two technologies.
This work proposes a strategy that combines the two physical layer techniques by adopting a common medium access control protocol, and analyzes the performance of the solution under specific application scenarios.
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MQW Laser Diode Photoacoustic Detection of Formaldehyde
in 2,3 micro-meter Spectral Range
J. Cihelka1, and S. Civiš1, I. Matulková2
1J. Heyrovský Institute of Physical Chemistry, Czech Republic
2Academy of Science of the Czech Republic, Czech Republic
Abstract
The spectrum of formaldehyde was studied in the 4350 - 4361 cm-1 region using photoacoustic detection in combination with a semiconductor GaInAsSb/AlGaAsSb diode laser as a radiation source. This laser operates at laboratory and higher temperatures in the 4342 – 4362 cm-1 region with an output of about 1 mW. The spectrum of formaldehyde was measured photoacoustically and this was compared with other techniques, such as laser absorption in a single path 0.4 m long cell and Fourier transform spectroscopy. The dependence of the photoacoustic signal on the pressure of the measured gas was recorded. The same technique was employed to determine the detection limit (less than 0.1 ppmV) of formaldehyde diluted with nitrogen for the strongest absorption line in the emission region of the diode laser.
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Soliton Propagation in Coupled Resonator Optical Waveguides: Application
to Optical Delay Lines
J. Cihelka1, and S. Civiš1, I. Matulková2
1National and Kapodistrian University of Athens, Greece
2Panepistimiopolis Ilyssia, Athens, Greece
Abstract
In this paper, the feasibility of realizing optical delay lines based on soliton propagation in Coupled Resonator Optical Waveguides (CROWs) is numerically analyzed. For a given bit rate and required delay, design equations are given that relate the soliton peak amplitude and collision period to the soliton width. The stability of CROW solitons, in the presence of higher order dispersion, optical loss and adjacent soliton pulses is numerically verified. It is also shown that soliton-based CROW delay lines can achieve ns delay at a propagation length of a few mm, due to the high slow down factors that can be obtained. This could open up a path towards realizing compact optical delay lines in integrated form.
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Features of formation of radar-tracking and optical images in a mobile
test complex of radiovision systems of the car
A. Ananenkov, A. Konovaltsev, A. Kukhorev, V. Nujdin, V. Rastorguev
Moscow Aviation Institute (State Technical University), Russia
Abstract
In the report features of formation of radar images (RI) and optical images (OI) in the mobile test complex of radio vision systems (RVS) of the car are presented. The system of radiovision of the car (CRVS) of the MM-wavelength with frequency modulation is considered. Features of formation and processing of the radar-tracking image (RI) in CRVS are discussed, in particular: the sizes of the image, system of coordinates, primary and secondary processing of RI, requirements till speeds of transfer of figures, real time of processing, a subsystem of display of RI and synchronization. The structure of the mobile test complex of CRVS is described. This complex consists of: CRVS, a video-camera, the module of formation, record and display of RI and of optical images (OI), the module of control of a complex, the power supply unit. Features of formation and display OI are considered, in particular: the coordination of scale and a foreshortening of images, maintenance of time synchronization at display and records of OI, and questions of synchronous fusion RI and OI also.
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