Optical Society of America

Displaying 41-71 of 71 results

  • 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 // 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 // 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 // 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 // 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

    Experimental Validation of End-to-End GMPLS-Enabled Restoration in Multi-Domain Transparent WSON

    Two GMPLS restoration strategies operating at wavelength and link granularities are experimentally validated in a multi-domain WSON. The strategies are qualitatively compared in terms of resource usage, restorability and restoration time. In Wavelength Switched Optical Networks (WSON), a link or node failure causes a huge amount of data loss. Fast...

    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 // 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 // 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 // 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 // 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 // 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 // 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 // Oct 2009

    Availability-Aware Routing for Large-Scale Hybrid Wireless-Optical Broadband Access Network

    In large-scale hybrid wireless-optical broadband access networks, the availability of wireless links and optical links varies considerably. Availability-aware routing can significantly improve availability and throughput by encouraging more usage of PON. Hybrid Wireless-Optical Broadband Access Network (WOBAN) consists of a multi-hop Wireless Mesh Network (WMN) at the front-end and an...

    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 // 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 // Sep 2009

    Resource Criticality Analysis of Static Resource Allocations and Its Applications in WDM Network Planning

    Various static resource allocation algorithms have been used in WDM networks to allocate resources such as wavelength channels, transmitters, receivers, and wavelength converters to a given set of static lightpath demands. However, although optimized resource allocations can be obtained, it remains an open issue how to determine which resources are...

    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 // Jul 2009

    Effects of Outdated Control Information in Control-Plane-Enabled Optical Networks With Path Protection

    New signaling suites for a distributed control plane in Wavelength Division Multiplexing (WDM) networks, such as Generalized MultiProtocol Label Switching (GMPLS) and Automatic Switched Optical Networks (ASON), allow one to cope with the increasing variability of traffic patterns to be supported by operators by providing a means to dynamically set...

    Provided By Optical Society of America

  • White Papers // Jul 2009

    Enhanced Backwards Recursive Path Computation for Multi-Area Wavelength Switched Optical Networks Under Wavelength Continuity Constraint

    In the context of the future Internet, all optical wavelength switched optical networks will play an important role in either evolutionary or revolutionary design paradigms. In any paradigm, Dense Wavelength Domain Multiplexing (DWDM) is the most cost-effective technology to increase bandwidth capacity. DWDM provides the basis for a core optical...

    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

  • 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 // 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 // Apr 2009

    Spectrally Efficient Hybrid Multiplexing and Demultiplexing Schemes Toward the Integration of Microwave and Millimeterwave Radio-Over-Fiber Systems in a WDM-PON Infrastructure

    Hybrid multiplexing and de-multiplexing schemes with the capability to integrate microwave and millimeter-wave frequency radio-over-fiber signals in a Wavelength Division Multiplexed Passive Optical Network (WDM-PON) infrastructure are proposed. The proposed schemes exploit the benefits of a spectrally efficient wavelength-interleaving technique and enhance the performance of optical millimeter-wave signals without employing...

    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 // Feb 2009

    Integrated Polymer Microprisms for Free Space Optical Beam Deflecting

    Authors demonstrate beam deflection and multiple channel communication in free space optical communications using microprisms integrated directly onto an array of Vertical Cavity Surface Emitting Lasers (VCSELs). The design and fabrication of such a transmitter is presented, and shown to achieve beam deflection of up to 10? in a planar...

    Provided By Optical Society of America

  • White Papers // Feb 2009

    Virtualizing and Scheduling Optical Network Infrastructure for Emerging IT Services

    Emerging IT services providers which aim at delivering supercomputing power available to the masses over the Internet, rely on high performance IT resources interconnected with ultra-high performance optical networks. To adjust the provisioning of the resources to end-user demand variations, new infrastructure capabilities have to be supported. These capabilities have...

    Provided By Optical Society of America