Optical Society of America

Displaying 1-40 of 69 results

  • White Papers // Dec 2011

    Elastic Spectrum Allocation for Variable Traffic in Flexible-Grid Optical Networks

    The currently deployed Wavelength Division Multiplexing (WDM) optical networks operate within a rigid frequency grid and with single-line-rate transponders making use of single carrier modulation techniques. The evolution path of optical transport networks can be translated to the application of advanced single-carrier modulation formats (such as QPSK, 16-QAM) in mixed-line-rate...

    Provided By Optical Society of America

  • White Papers // Feb 2012

    Statistical Approach for Fast Impairment-Aware Provisioning in Dynamic All-Optical Networks

    Physical Layer Impairments (PLIs) need to be considered in the Routing and Wavelength Assignment (RWA) process of all-optical networks to ensure the provisioning of good quality optical connections (i.e., light-paths). A convenient way to model the impact of PLIs on the signal quality is to use the so-called Q-factor. In...

    Provided By Optical Society of America

  • White Papers // Aug 2011

    Building Data Centers With Optically Connected Memory

    Future data centers will require novel, scalable memory architectures capable of sustaining high bandwidths while still achieving low memory access latencies. Electronic interconnects cannot meet the challenges presented by the need for multi-terabit off-chip memory data paths. In this paper, the electronic bus between main memory and its host processor...

    Provided By Optical Society of America

  • White Papers // Aug 2012

    Multicast Overlay for High-Bandwidth Applications Over Optical WDM Networks

    Multicast communication in Wavelength Division Multiplexed (WDM) networks is traditionally supported by the assumption that the optical cross-connects are multicast capable, i.e., they are capable of switching an incoming signal to more than one output interface. A na?ve method of supporting this functionality in a Multicast-Incapable (MI) environment is by...

    Provided By Optical Society of America

  • White Papers // Dec 2012

    Relay Selection Protocols for Relay-Assisted Free-Space Optical Systems

    The authors investigate transmission protocols for relay-assisted Free-Space Optical (FSO) systems, when multiple parallel relays are employed and there is no direct link between the source and the destination. As alternatives to all-active FSO relaying, where all the available relays transmit concurrently, they propose schemes that select only a single...

    Provided By Optical Society of America

  • White Papers // Apr 2013

    Capacity and Nonuniform Signaling for Discrete-Time Poisson Channels

    The Poisson photon-counting model is accurate for optical channels with low received intensity, such as long-range intersatellite optical wireless links. This paper considers the computation of the channel capacity and the design of capacity-approaching, nonuniform signaling for discrete-time Poisson channels in the presence of dark current and underaverage and peak...

    Provided By Optical Society of America

  • White Papers // Dec 2009

    Broadband Hitless Silicon Electro-Optic Switch for On-Chip Optical Networks

    This paper report on the demonstration of a broadband (60 GHz), spectrally hitless, compact (20 ?m x 40 ?m), fast (7 ns) electro-optical switch. The device is composed of two coupled resonant cavities, each with an independently addressable PIN diode. This topology enables operation of the switch without perturbing adjacent...

    Provided By Optical Society of America

  • White Papers // Apr 2009

    Single Port Optical Switching in Integrated Ring Resonators

    Semiconductor ring lasers (SRLs) are attractive components for all-optical signal processing. They typically lase bidirectional at low drive current and unidirectional at high current due to gain suppression between the Competing Clockwise (CW) and counter-clockwise (CCW) modes. This unidirectionality can potentially be utilized for bistable operation by switching between the...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Experimental Demonstration of Optical Switching and Routing Via Four-Wave Mixing Spatial Shift

    The paper demonstrates the shift characteristics of Four-Wave Mixing (FWM) beam spots which are controlled by the strong laser fields via the large cross-Kerr nonlinearity. The shift distances and directions are determined by the nonlinear dispersions. Based on such spatial displacements of the FWM beams, as well as the probe...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Point-to-Multipoint VLAN Path Signaling Demonstration on the GMPLS Controlled Ethernet Test Network

    Ethernet has greatly succeeded in Local Area Network (LAN). A simple forwarding scheme of Ethernet facilitated the development of high-speed and cost-effective Ethernet equipments. Ethernet is now expanding from LAN to Wide Area Network (WAN) as a carrier grade transport network. The carrier grade Ethernet will replace legacy transport network...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Comparison of Static and Dynamic WDM Networks in Terms of Energy Consumption

    Currently, telecommunication networks have been reported to account for 1-10% of the world's energy consumption. Given the ever increasing demand for Internet traffic, this figure is expected to keep growing. As a result, taking into account energy consumption is key in the design of next-generation networks. Core networks are at...

    Provided By Optical Society of America

  • White Papers // Apr 2010

    Transparent High-Data-Rate Optical Transmission Through Broadband Hitless Bypass Switches for Chip-Scale Optical Networks

    Silicon photonics has been realized to provide outstanding performance in very broad range of applications such as short-haul communication, and on-chip global interconnection networks in multi-core microprocessors. The most pertinent advantages of silicon photonics are its large bandwidth, low energy consumption, and small footprint components. Furthermore, silicon photonics provides large...

    Provided By Optical Society of America

  • White Papers // Aug 2010

    Clustering Methods for Hierarchical Traffic Grooming in Large-Scale Mesh WDM Networks

    This paper considers a hierarchical approach for traffic grooming in large multiwavelength networks of a general topology. Inspired by similar concepts in the airline industry, the author decomposes the network into clusters, and selects a hub node in each cluster to groom traffic originating and terminating locally. At the second...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Cross-Layer Traffic Grooming for Optical Networks With Hybrid Layer-One and Layer-Zero Signal Regeneration

    Traffic grooming is important for optical transport networks. Most of studies in this area have focused on minimizing total network capacity or maximizing total served traffic demand subject to predefined network capacity. When planning lightpath demand, the existing traffic grooming studies often ignored the impairments in the physical layer. However,...

    Provided By Optical Society of America

  • White Papers // Apr 2010

    Broadband All-Optical Modulation in Hydrogenated-Amorphous Silicon Waveguides

    the authors demonstrate broadband all-optical modulation in low loss hydrogenated-amorphous silicon (a-Si:H) waveguides. Significant modulation (~3 dB) occurs with a device of only 15 ?gm without the need for cavity interference effects in stark contrast to an identical crystalline silicon waveguide. the authors attribute the enhanced modulation to the significantly...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Does Header Length Affect Performance in Optical Burst Switched Networks?

    This paper investigates the impact of non-negligible Header Length (HL) in optical burst switching on blocking probability. The header length is the total delay of a control packet at the controller. he authors first develop a model that explicitly presents the distribution of offset times as a function of the...

    Provided By Optical Society of America

  • White Papers // Jan 2010

    Evaluation of Protection Reconfiguration for Multiple Failures in Optical Networks

    Protection and restoration are important in designing reliable optical networks and have been widely studied in the literature. Most practical studies of high-speed recovery algorithms assume only a single-link or single-node failure model. As networks grow in size and complexity, both the likelihood and the impact of failures increase. In...

    Provided By Optical Society of America

  • White Papers // May 2010

    Adaptive Modulation and Coding for Free-Space Optical Channels

    Adaptive modulation and coding can provide robust and spectrally efficient transmission over terrestrial free-space optical channels. Three adaptive modulation schemes are considered in this paper: variable-rate variable-power adaptation, channel inversion, and truncated channel inversion schemes. It is shown that a simple channel inversion scheme performs comparable to a variablerate variable-power...

    Provided By Optical Society of America

  • White Papers // Oct 2009

    Coded PPM and Multipulse PPM and Iterative Detection for Free-Space Optical Links

    Signal modulation has an important impact on the system performance in optical communication. Two attractive modulation schemes are Pulse Position Modulation (PPM) and Multi Pulse PPM (MPPM), which have the advantage of average energy efficiency and bandwidth efficiency, respectively. An important practical issue is to employ an efficient channel coding...

    Provided By Optical Society of America

  • White Papers // Oct 2009

    Fading Reduction by Aperture Averaging and Spatial Diversity in Optical Wireless Systems

    Atmospheric turbulence can cause significant performance degradation in free-space optical communication systems. It is well known that the effect of turbulence can be reduced by performing aperture averaging and ? or employing spatial diversity at the receiver. In this paper, authors provide a synthesis on the effectiveness of these techniques...

    Provided By Optical Society of America

  • White Papers // Apr 2009

    Online Excess Bandwidth Distribution for Ethernet Passive Optical Networks

    Excess bandwidth distribution techniques have recently been proposed to improve the dynamic bandwidth allocation in Ethernet Passive Optical Networks (EPONs). This paper compares existing offline excess bandwidth distribution with conventional limited Interleaved Polling with Adaptive Cycle Time (IPACT-limited) in terms of packet delay performance. This paper identifies the factors that...

    Provided By Optical Society of America

  • White Papers // Nov 2010

    LDPC-Coded Orbital Angular Momentum (OAM) Modulation for Free-Space Optical Communication

    An Orbital Angular Momentum (OAM) based LDPC-coded modulation scheme suitable for use in FSO communication is proposed. They demonstrate that the proposed scheme can operate under strong atmospheric turbulence regime and enable 100 Gb/s optical transmission while employing 10 Gb/s components. Both binary and nonbinary LDPC-coded OAM modulations are studied....

    Provided By Optical Society of America

  • White Papers // Aug 2009

    Rotational Multiphoton Endoscopy With a 1?M Fiber Laser System

    This paper presents multiphoton microendoscopy with a rotational probe and a 1 ?m fiber-based femtosecond laser. The rotational probe is based on a double-clad photonic crystal fiber, a gradient index lens, a microprism, and a rotational MicroElectronicMechanical system (MEMS) motor. The MEMS motor has a diameter of 2.2 mm and...

    Provided By Optical Society of America

  • White Papers // Dec 2009

    Large Area High Efficiency Broad Bandwidth 800 nm Dielectric Gratings for High Energy Laser Pulse Compression

    The grating compressor is one of the most critical components of a high power Chirped Pulse Amplification (CPA) laser system. Requirements for the diffraction gratings include: high diffraction efficiency, high damage threshold, and often the ability to withstand high average powers. Until recently, CPA laser systems have almost exclusively made...

    Provided By Optical Society of America

  • White Papers // Mar 2010

    Network Coding in Optical Networks With O/E/O Based Wavelength Conversion

    Network coding is a process by which messages are encoded and sent across computer networks and then decoded at the receivers to optimize use of bandwidth as well as reliability. Optical networks have their own unique properties which affect the way network coding is performed on them. Previous work on...

    Provided By Optical Society of America

  • White Papers // Feb 2010

    Wireless-PONs With Extended Wavelength Band Overlay

    A novel network architecture featuring wireless transmission by means of FDM over multi-wavelength splitter PONs for enhanced network scalability is described. Assuming the application of a 40-port commercially available DAWG and 16 ONU/BSs per PON with minimum 50 users per WiMAX sector, more than 96000 wireless users can be served...

    Provided By Optical Society of America

  • White Papers // Mar 2011

    A Torus-Based 4-Way Fault-Tolerant Backbone Network Architecture for Avionic WDM LANs

    In this paper, the authors leverage the torus topology to design a Wavelength Division Multiplexing (WDM) backbone network for operation in hazardous avionic environments. The proposed WDM local area network offers efficient data delivery and fast fault recovery via establishing four non-overlapping lightpaths for any source-destination pair. First, they describe...

    Provided By Optical Society of America

  • White Papers // Dec 2010

    Economics of Time and Wavelength Domain Multiplexed Passive Optical Networks

    Passive Optical Networks (PONs) are being widely considered as a means to implement Fiber-To-The Home (FTTH) and deliver broadband access to business and home users. However, technical and consequently regulatory and economic complexities arise in light of their deployment. In this paper, an evaluation of the business prospects of Time...

    Provided By Optical Society of America

  • White Papers // Dec 2010

    Diversity-Multiplexing Trade-Off in Coherent Free-Space Optical Systems With Multiple Receivers

    In this paper, from an information theory point of view, the authors investigate the performance of a coherent Free Space Optical (FSO) communication system with multiple receives apertures over atmospheric turbulence channels. Their study builds on a recently introduced statistical model that characterizes the combined effects of turbulence-induced wave front...

    Provided By Optical Society of America

  • White Papers // May 2009

    Multihopping and Waveband Assignment in Limited Reconfigurable WDM Networks

    In reconfigurable optical networks, the lightpaths are dynamically adjusted by the use of Reconfigurable Optical Add/Drop Multiplexers (ROADMs). Reconfiguration also requires tunable transmitters and receivers (transponders). Fully reconfigurable ROADMs that can add/drop any wavelength to any port (i.e., ROADMs with colorless ports) use tunable transponders at the add/drop ports. It...

    Provided By Optical Society of America

  • White Papers // May 2010

    Performance of Short-Range Non-Line-of-Sight LED-Based Ultraviolet Communication Receivers

    Utilizing an empirical path loss model proposed in the first paper of a two-part series, the bit error rate performance of short-range non-line-of-sight ultraviolet communication receivers is analyzed. Typical photodetector models and modulation formats are considered. The authors' results provide semi-analytical prediction of the achievable communication performance as a function...

    Provided By Optical Society of America

  • White Papers // Jan 2011

    Double-Laser Differential Signaling for Reducing the Effect of Background Radiation in Free-Space Optical Systems

    In order to reduce the impact of background radiation on the performance of terrestrial free-space optical systems, the authors propose to use two laser wavelengths and to perform the data detection at the receiver in a differential mode. They consider first the case of simple on - off keying modulation...

    Provided By Optical Society of America

  • White Papers // Feb 2011

    Lessons Learned From Implementing a Path Computation Element (PCE) Emulator

    The authors developed the first open source Path Computation Element (PCE) emulator, which includes a complete PCEP protocol implementation, network I/O support and support for concurrent path computations. They share the lessons learned in its implementation. The upcoming QoS sensitive services such as IPTV, VoD, etc, are making path computation...

    Provided By Optical Society of America

  • White Papers // Apr 2011

    Dimensioning the Future Pan-European Optical Network With Energy Efficiency Considerations

    This paper studies the overall energy consumption of a pan-European optical transport network for three different time periods: today and in five and ten years from now. In each time period the pan-European network was dimensioned using traffic predictions based on realistic data generated by the optical networking roadmap developed...

    Provided By Optical Society of America

  • White Papers // Jul 2011

    Fast Exact ILP Decompositions for Ring RWA

    Wavelength division multiplexing rings are now capable of supporting more than 100 wavelengths over a single fiber. Conventional link and path formulations for the routing and wavelength assignment problem are inefficient due to the inherent symmetry in wavelength assignment and the fact that the problem size increases fast with the...

    Provided By Optical Society of America

  • White Papers // Oct 2010

    Quality-of-Transmission-Aware Manycasting Over Optical Burst-Switched Networks

    Many next-generation distributed applications, such as grid computing, require a single source to communicate with a group of destinations. Traditionally, such applications are implemented using multi-cast communication. A typical multi-cast session requires creating the shortest-path tree to a fixed number of destinations. The fundamental issue in multi-casting data to a...

    Provided By Optical Society of America

  • White Papers // Oct 2009

    Multicasting in Wireless Sensor Networks

    Wireless sensor networks are embedded networks that are highly restricted to energy, bandwidth and processing power. Even though wireless sensor networks operate with limited resources, sensor nodes are required to do more functions compared to nodes in other data networks. Sensor nodes work as both hosts for processing sensed data...

    Provided By Optical Society of America

  • White Papers // Sep 2009

    Information Theoretical Analysis of Hierarchical Nano-Optical Systems in the Sub wavelength Regime

    Optical near-field interactions exhibit a hierarchical response, which is one of the most unique attributes of light - matter interactions occurring locally on the nanometer scale. It allows hierarchical nano-optical systems that break through the integration restrictions posed by the diffraction limit of conventional propagating light and offers multiple hierarchical...

    Provided By Optical Society of America

  • White Papers // Jun 2009

    Energy-Minimized Design for IP Over WDM Networks

    As the Internet expands in reach and capacity, the energy consumption of network equipment increases. To date, the cost of transmission and switching equipment has been considered to be the major barrier to growth of the Internet. But energy consumption rather than cost of the component equipment may eventually become...

    Provided By Optical Society of America

  • White Papers // Jun 2009

    Cost Minimization Planning for Greenfield Passive Optical Networks

    The authors plan green-field PON networks to minimize their total deployment costs. They propose an efficient heuristic called the Recursive Association and Relocation Algorithm (RARA) to solve the optimization problem. Their algorithm can significantly reduce PON network deployment costs compared to an intuitive random-cut sectoring approach. To further tune down...

    Provided By Optical Society of America