Download or read book Long Reach RSOA Based Passive Optical Networks written by Sourav Mondal and published by LAP Lambert Academic Publishing. This book was released on 2014-10-01 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present access services like video on demand, live streaming, online gaming etc. require enormous amount of bandwidth and traditional digital subscriber line technology fails to meet up this requirement. The next generation networks, in particular, hybrid WDM-TDM Long-Reach Passive Optical Networks provide the required bandwidth and reduce the operational expenditure. Laser sources used at the Optical Network Units increase the cost due the extra equipment required for stabilizing the operating wavelength. To overcome this, a centralized source is installed at the Optical Line Terminal and the signal is reflected and intensity-modulated at the ONU, by using a special optical device Reflective Semiconductor Amplifier (RSOA), thus making the end receiver unit "colourless." The analytical model for RSOA has been described in detailed in this book. The primary objective of this enitre work is to examine the feasibility of hybrid WDM-TDM LR-PON physical layer uplink setup consisting of reflective ONUs with due consideration to the BER performance in presence of realistic and non-ideal characteristics of optical and optoelectronic devices used in the setup.

Download or read book Optical Fiber Telecommunications VIB written by Y.C. Chung and published by Elsevier Inc. Chapters. This book was released on 2013-05-11 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wavelength-division-multiplexed passive optical network (WDM PON) has long been considered as an ultimate solution for the future optical access network capable of providing practically unlimited bandwidth to each subscriber. On the other hand, it is still considered to be too expensive for the massive deployment. To solve this problem and meet the ever-increasing demand for bandwidth, there have been numerous efforts to improve the competitiveness of WDM PON. This chapter reviews the current status and future direction of these WDM PON technologies. We first review various colorless light sources, which are critical for the cost-effective implementation of the optical network units (ONUs), and several representative network architectures proposed for WDM PONs. We then review the recent research activities for the realization of high-speed (>10Gb/s) and long-reach WDM PONs. Various fault-monitoring and protection techniques are also reviewed as they can be increasingly important in the future high-capacity WDM PONs.

Download or read book Long Reach Passive Optical Networks written by Huan Song and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the advances in optical technology, the span of a broadband access network using Passive Optical Network (PON) technology can be increased from today's standard of 20 km to 100 km or higher. Such an extended-reach PON is known as Long-Reach PON (LR-PON). This technology can enable broadband access for a large number of customers in the access/metro area, while decreasing capital and operational expenditures for the network operator. Therefore, it is very desirable to comprehensively investigate this technology for future broadband access. This dissertation is dedicated to the research of architecture, management, and reliability of LR-PON. This dissertation first reviews the evolutionary path of access networks and shows the drivers from technology and business perspectives for high bandwidth and low cost. A variety of research challenges in this field is reviewed, from optical components in the physical layer to the control and management issues in the upper layers. We discuss the requisites for optical sources, optical amplifiers, and optical receivers in optical access networks with high transmission rate (10 Gbps) and large power attenuation (due to large split, transmission over 100 km and beyond, and propagation). We analyze the key topological structures to guarantee physical protection (e.g., tree-and-branch, ring-and-spur). Then, some relevant demonstrations of Long-Reach optical access networks developed worldwide by different research institutes are presented. A major challenge in LR-PON is that the propagation delay (for data as well as control signals) between the telecom central office (CO) and the end user is increased by a very significant amount. Now, traditional PON algorithms for scheduling the upstream transmission, such as dynamic bandwidth allocation (DBA) algorithms, may not be sufficient; actually, they may lead to degraded performance because of the long delay of the CO-to-Users "control loop". This challenge motivates us to propose and study a multi-thread polling algorithm to effectively and fairly distribute the upstream bandwidth dynamically. This algorithm exploits the benefits of having multiple polling processes running simultaneously and enabling users to send bandwidth requests before receiving acknowledgement from the CO. We compare the proposed algorithm with traditional DBA, and show its advantage on average packet delay. With the increased bandwidth requests from the expanding base of users, LR-PON should utilize the network resource (e.g., wavelengths, lasers, etc.) more effectively. We propose a new and efficient protocol to achieve better utilization of tunable lasers, as well as wavelength resources across different user groups in LR-PON. In order to accommodate downstream bursty traffic and provide Quality of Service (QoS) in the user-specified Service-Level Agreements (SLA), the protocol integrates our proposed SLA-aware bandwidth allocation scheme based on flow scheduling. We show the protocol's advantage to support incremental upgrade of bandwidth with increasing user bandwidth requests, and to provide a user with a SLA which guarantees a number of streaming flows with average bandwidth and maximum delay guarantee (e.g., 5 ms), as well as data flows with average bandwidth specifications. Since LR-PON serves a lot more users, a network failure may lead to a huge amount of data loss and negative user experience. Thus, to understand the importance of LR-PON survivability, we propose hardware-accelerated protection schemes for the LR-PON, incorporating the "ring-and-spur" structure to achieve fast protection-switching time, and automatic failure location at the Optical Line Terminal (OLT), which is located at the head end of the optical access network. We design the protection schemes for multiple network environments, e.g., unidirectional transmission vs. bidirectional transmission, and 1+1 protection vs. 1:1 protection. The numerical examples demonstrate that protection paths can be established within a few tens of ms after a failure occurs. This dissertation makes important contributions by studying novel architectures, protocols, and algorithms of LR-PON that will help to improve the next-generation telecom access networks.

Download or read book Energy efficient Long reach Passive Optical Networks written by Lei Shi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To bring the high capacity of the optical fiber closer to the end users with affordable costs, passive optical network (PON) was introduced and developed as a promising access network technology over the past decade. Long-reach PON (LR-PON) extends the coverage span of PONs from the traditional 20 km range to 100 km, consolidates the multiple active sites and thus lowers the costs. Besides extending the reach, energy conservation, which is of growing concern today, gives LR-PON a brand new advantage over its competitors. In this dissertation, we focus on the intersection of these two topics, namely Energy-Efficient LR-PON. We present several distinct schemes with the potential for substantial energy savings under practical settings, while not significantly affecting the network's performance. We develop and evaluate novel architectures, protocols, and algorithms for a LR-PON to will help to improve the performance of next-generation telecom access networks. One major component of LR-PON is the optical line terminal (OLT), which is deployed in central offices. Specifically for energy savings in OLT, we propose a centralized network planning approach based on user behaviors. By considering the different network usage behaviors of different kinds of users, we develop an efficient user-assignment scheme in which users with complementary behaviors are assigned to the same network segment to share the bandwidth. This achieves high bandwidth utilization at all times, and reduces the number of wavelengths needed, thus lowing cost and energy usage. Heuristic searches can provide such assignments, and their approximate solutions are very close to the lower bound. We then extend our work to the network operation (i.e., traffic engineering) stage, where an energy-efficient dynamic wavelength allocation scheme is developed on the "ring-and-spur" LR-PON. This scheme enables a wavelength to be dropped dynamically at multiple remote nodes, making it possible for users in different network segments to share downstream capacity in a statistical multiplexing fashion. The wavelength allocation may also be dynamically changed according to the network traffic so that the OLT can efficiently utilize all operational wavelengths. The other major component of LR-PON is the optical network unit (ONU), a remote unit close to the users. We propose a service-level agreement (SLA)-based scheduling scheme, in which the sleep time of an ONU can be adjusted and the ONU can quit sleep mode to send high-priority packets. Our proposal solves the problems of slow transition of power from active mode to sleep mode in an ONU and the relatively large recovery and synchronization time needed during the wakeup process. The tradeoff in energy savings vs. delay performance is evaluated using simulations under practical power-consumption settings. We also study the effects of arrayed-waveguide grating (AWG) and erbium-doped-fiber amplifier (EDFA) on bit-error rate (BER) in LR-PON, and propose both short-term and long-term distance-aware wavelength allocation schemes to balance the BER among ONUs at different distances. Simulation results show that average BER improves and the relative standard deviation decreases.

Download or read book Next Generation FTTH Passive Optical Networks written by Josep Prat and published by Springer Science & Business Media. This book was released on 2008-07-16 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fibre-to-the-Home networks constitute a fundamental telecom segment with the required potential to match the huge capacity of transport networks with the new user communication demands. Huge investments in access network infrastructure are expected for the next decade, with many initiatives already launched around the globe recently, driven by the new broadband service demands and the necessity by operators to deploy a future-proof infrastructure in the field. Dense FTTH Passive Optical Networks (PONs) is a cost-efficient way to build fibre access, and international standards (G/E-PON) have been already launched, leading to new set of telecom products for mass deployment. However, these systems only make use of less than 1% of the optical bandwidth; thus, relevant research is taking place to maximize the capacity of these systems, with the latest opto-electronic technologies, demonstrating that the huge bandwidth available through the fibre access can be exploited in a cost-efficient and reliable manner. Next-Generation FTTH Passive Optical Networks gathers and analyzes the most relevant techniques developed recently on technologies for the next generation FTTH networks, trying to answer the question: what’s after G/E-PONs?

Download or read book Passive Optical Networks written by Cedric F. Lam and published by Elsevier. This book was released on 2011-10-10 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Passive optical network (PON) technologies have become an important broadband access technology as a result of the growing demand for bandwidth-hungry video-on-demand applications. Written by the leading researchers and industry experts in the field, Passive Optical Networks provides coherent coverage of networking technologies, fiber optic transmission technologies, as well as the electronics involved in PON system development. Features: - An in-depth overview of PON technologies and the potential applications that they enable - Comprehensive review of all major PON standards and architecture evolutions, as well as their pros and cons - Balanced coverage of recent research findings with economic and engineering considerations - Presents system issues of protocols, performance, management and protection - Extensive references to standards and research materials for further studies This book provides an authoritative overview of PON technologies and system requirements and is ideal for engineers and managers in industry, university researchers, and graduate students. - Balances treatment of the optical technologies with systems issues such as protocols, performance, management and protection - Covers latest developments in WDM-PONS, protection switching, dynamic bandwidth allocation - Practical coverage with a chapter on PON applications and deployment - Case studies on implementing PONs

Download or read book A Novel Multi band CO OFDM Based Long Reach Passive Optical Network Architecture written by Mohamed Ben Zeglam and published by . This book was released on 2017 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis investigates a new long-reach passive optical networks (LRPON) architecture based on multi-band coherent optical orthogonal frequency division multiplexing (CO-OFDM). The proposed CO-OFDM based LRPON system is characterized by a novel phase noise compensation mechanism aiming to deal with optical signal dispersion in long-range transmissions. By employing a dispersion compensating fiber (DCF) and local oscillator (LO) laser phase shifter for each end-to-end transmission between OLT and ONU, we will show the phase noise due to dispersion can be effectively mitigated. Simulation of the downlink traffic between one optical line terminal (OLT) and 12 optical network units (ONUs) is performed successfully at different fiber lengths, at the data rate of 10$Gbps$ per ONU. The required BER for the forward error correction (FEC) has been achieved for most ONUs, using a dispersion compensating fiber (DCF) and local oscillator (LO) laser phase shifter to compensate for the chromatic dispersion (CD) and the polarization mode dispersion (PMD), respectively.

Download or read book The ComSoc Guide to Passive Optical Networks written by Stephen B. Weinstein and published by John Wiley & Sons. This book was released on 2012-04-24 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the major architectures, standards, and technologies of Passive Optical Networks (PONs) The ComSoc Guide to Passive Optical Networks provides readers with a concise explanation of the key features of Passive Optical Networks (PONs); the different types of PON architectures and standards; key issues of PON devices, management, and implementation; and the promising business opportunities in access networks. Written for a broad audience, ranging from developers to users, this indispensable book provides an understanding o the evolutionary path of PON access systems and their positioning with respect to the cable, copper, and wireless competitors for broadband access networks. In addition, The ComSoc Guide to Passive Optical Networks: Provides brief, high-level overviews of the architectures and applications of Fiber-to-the-Home (FTTH) or Fiber-to-the-Curb (FTTC) access networks and the alternative HFC, subscriber line, and WiMAX access systems Awards readers with a clear understanding of what BPON, GPON, WDM-PON and EPON are and how they work, together with an introduction to their respective standards Carefully defines all acronyms and technical terms, making the book accessible to those who may not be specialists in this area Gives readers an appreciation of the last mile problems in telecommunications access networks, and the opportunities in optical-wireless integration

Download or read book 10GB S Burst Mode Transmission in Long Reach Passive Optical Networks written by Cleitus Antony and published by . This book was released on 2010 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Long reach passive optical networks (PONs) are currently emerging as one of the leading candidates for the next generation of telecommunications access networks, which will provide end customers with future high bandwidth interactive and video-rich services. In order to satisfy future bandwidth demand in an economic fashion it is likely that PON technology will need to evolve dramatically from that which is commercially available today. In particular the reach of these networks will need to increase fivefold to around 100km and the supported data rates will jump by nearly an order of magnitude to around 10Gb/s. In this thesis a hybrid dense wavelength division multiplexed- time division multiple access passive optical network (DWDM-TDMA PON) suitable for use in next generation optical access networks is proposed and studied. In order to implement such challenging architectures new types of high speed, burst mode optical transmission techniques are required, which enable bandwidth sharing between users on the network. This project has developed these new burst mode techniques and sub-systems required to enable these new networks. The main aim of the investigations in this thesis are in overcoming all the physical layer challenges due to 10Gb/s burst mode nature of transmission in these types of networks. A range of investigations, both of a theoretical and experimental nature, such as the dynamics of optical amplifiers, interferometric noise mitigation, suppression of crosstalk from multiple sources, maximum transmission distance, etc., are carried out to optimise the performance of individual components as well as the fully integrated system. The suitability of hybrid DWDM-TDMA architectures as a cost effective solution for use in future optical access networks is verified through full-scale network demonstrations in an experimental long reach PON laboratory test-bed.

Download or read book Quantum Dot Based Semiconductor Optical Amplifiers for O Band Optical Communication written by Holger Schmeckebier and published by Springer. This book was released on 2016-10-21 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines the unique properties of gallium arsenide (GaAs)-based quantum-dot semiconductor optical amplifiers for optical communication networks, introducing readers to their fundamentals, basic parameters and manifold applications. The static and dynamic properties of these amplifiers are discussed extensively in comparison to conventional, non quantum-dot based amplifiers, and their unique advantages are elaborated on, such as the fast carrier dynamics and the decoupling of gain and phase dynamics. In addition to diverse amplification scenarios involving single and multiple high symbol rate amplitude and phase-coded data signals, wide-range wavelength conversion as a key functionality for optical signal processing is investigated and discussed in detail. Furthermore, two novel device concepts are developed and demonstrated that have the potential to significantly simplify network architectures, reducing the investment and maintenance costs as well as the energy consumption of future networks.

Download or read book Optical Access Networks and Advanced Photonics Technologies and Deployment Strategies written by Chochliouros, Ioannis P. and published by IGI Global. This book was released on 2009-07-31 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book presents a comprehensive overview of emerging optical access network solutions to efficiently meet the anticipated growth in bandwidth demand"--Provided by publisher.

Download or read book Mobile Computing Solutions for Healthcare Systems written by Sivakumar R. and published by Bentham Science Publishers. This book was released on 2023-02-28 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on recent developments in integrating AI, machine learning methods, medical image processing, advanced network security, and advanced antenna design techniques to implement practical Mobile Health (M-Health) systems. The editors bring together researchers and practitioners who address several developments in the field of M-Health. Chapters highlight intelligent healthcare IoT and Machine Learning based systems for personalized healthcare delivery and remote monitoring applications. The contents also explain medical applications of computing technologies such as Wireless Body Area Networks (WBANs), wearable sensors, multi-factor authentication, and cloud computing. The book is intended as a handy resource for undergraduate and graduate biomedical engineering students and mobile technology researchers who want to know about the recent trends in mobile health technology.

Download or read book Reconfigurable Technology for Future Optical Access Networks written by She-Hwa Yen and published by Stanford University. This book was released on 2011 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fiber-based access is recognized as the most promising technology for solving broadband bandwidth bottlenecks. Time division multiplexing passive optical networks (TDM-PONs) that are passive and non-reconfigurable are currently the most widely deployed type of fiber access networks. However, due to their passive nature, TDM-PONs faces several limitations such as inflexible service area coverage, lack of intelligence for control, and inability to counteract security attacks. In order to address the current limitations of optical access networks, we propose reconfigurable technologies for next generation PONs. Two novel reconfigurable technologies are proposed, analyzed, and experimentally evaluated. The first solution is a reconfigurable power-and wavelength- assignment technology based on a novel non-volatile, reconfiguration node. The proposed remote node can reconfigure the network to adapt it to varying degrees of deployment conditions and/or network attacks. Moreover, the proposed remote node incorporates a novel quasi-passive device that does not consume energy once it is reconfigured into a new latching state. Therefore, the proposed remote node has very low energy consumption and does not require local power supply to preserve the passive character of the distribution network. In particular, two novel quasi-passive optical power splitter technologies based on Micro-Electro-Mechanical Systems (MEMS) and transition metal oxide have been designed for the reconfigurable device. A simulation study shows the proposed reconfigurable device would outperform traditional passive splitter in terms of maximum number of supportable users under realistic deployment conditions. The second solution addresses the issue of reconfigurable network consolidation and infrastructure simplification. Current TDM-PONs suffers from limited reach and split-ratio. To enhance the performance in terms of service range and quality of service, reconfigurable network consolidation is a promising solution. It can also simplify the network and reduce cost. We propose the following novel reconfigurable technologies for consolidation and simplification of next generation access networks: (1) Passive reach-extension technology for the drop section of optical access networks; (2) Sleep mode ONUs for energy saving; (3) Centrally managed optical signature that can monitor and protect the upstream link; and (4) Multi-rate burst mode receivers. These reconfigurable technologies can bring the intelligence into optical access networks and improve the efficiency and flexibility for next generation optical access networks.

Download or read book Investigation of Techniques for Long reach Passive Optical Networks LR PON written by Xiaodan Pang and published by . This book was released on 2010 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The ComSoc Guide to Passive Optical Networks written by Stephen B. Weinstein and published by John Wiley & Sons. This book was released on 2012-03-20 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the major architectures, standards, and technologies of Passive Optical Networks (PONs) The ComSoc Guide to Passive Optical Networks provides readers with a concise explanation of the key features of Passive Optical Networks (PONs); the different types of PON architectures and standards; key issues of PON devices, management, and implementation; and the promising business opportunities in access networks. Written for a broad audience, ranging from developers to users, this indispensable book provides an understanding o the evolutionary path of PON access systems and their positioning with respect to the cable, copper, and wireless competitors for broadband access networks. In addition, The ComSoc Guide to Passive Optical Networks: Provides brief, high-level overviews of the architectures and applications of Fiber-to-the-Home (FTTH) or Fiber-to-the-Curb (FTTC) access networks and the alternative HFC, subscriber line, and WiMAX access systems Awards readers with a clear understanding of what BPON, GPON, WDM-PON and EPON are and how they work, together with an introduction to their respective standards Carefully defines all acronyms and technical terms, making the book accessible to those who may not be specialists in this area Gives readers an appreciation of the last mile problems in telecommunications access networks, and the opportunities in optical-wireless integration

Download or read book Dynamic Bandwidth Allocation for Open Access and Long reach Passive Optical Networks written by Pedro Alvarez and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Topics on Optical Amplifiers in Present Scenario written by Sisir Garai and published by BoD – Books on Demand. This book was released on 2012-03-23 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the explosion of information traffic, the role of optics becomes very significant to fulfill the demand of super fast computing and data processing and the role of optical amplifier is indispensable in optical communication field. This book covers different advance functionalities of optical amplifiers and their emerging applications such as the role of SOA in the next generation of optical access network, high speed switches, frequency encoded all-optical logic processors, optical packet switching architectures, microwave photonic system, etc. Technology of improving the gain and noise figure of EDFA and, the study of the variation of material gain of QD structure are also included. All the selected topics are very interesting, well organized and hope it will be of great value to the postgraduate students, academics and anyone seeking to understand the trends of optical amplifiers in present scenario.