* The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The book presents sound coverage of the fundamentals of lightwave technology, along with material on pulse compression techniques and rare-earth-doped fiber amplifiers and lasers. The extensively revised chapters include information on fiber-optic communication systems and the ultrafast signal processing techniques that make use of nonlinear phenomena in optical fibers.New material focuses on the applications of highly nonlinear fibers in areas ranging from wavelength laser tuning and nonlinear spectroscopy to biomedical imaging and frequency metrology. Technologies such as quantum cryptography, quantum computing, and quantum communications are also covered in a new chapter.This book will be an ideal reference for: RD scientists involved with research on fiber amplifiers and lasers; graduate students and researchers working in the fields of optical communications and quantum information. * The only book on how to develop nonlinear fiber optic applications* Two new chapters on the latest developments; Highly Nonlinear Fibers and Quantum Applications* Coverage of biomedical applications

Applications of nonlinear fiber optics

Free space optical communication

In recent years, railway infrastructures and systems have played a significant role as a highly efficient transportation mode to meet the growing demand in transporting both cargo and passengers. Application of these structures in extreme environmental situation under severe working and loading conditions, caused by the traffic growth, heavier axles and vehicles and increase in speed makes it extremely susceptible to degradation and failure. In the last two decades, a significant number of innovative sensing technologies based on fiber optic sensors (FOS) have been utilized for structural health monitoring (SHM) due to their inherent distinctive advantages, such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. Fiber optic-based monitoring systems use quasi-distributed and continuously distributed sensing techniques for real time measurement and long term assessment of structural properties. This allows for early stage damage detection and characterization, leading to timely remediation and prevention of catastrophic failures. In this scenario, FOS have been proved to be a powerful tool for meticulous assessment of railway systems including train and track behavior by enabling real-time data collection, inspection and detection of structural degradation. This article reviews the current state-of-the-art of fiber optic sensing/monitoring technologies, including the basic principles of various optical fiber sensors, novel sensing and computational methodologies, and practical applications for railway infrastructure monitoring. Additionally, application of these technologies to monitor temperature, stresses, displacements, strain measurements, train speed, mass and location, axle counting, wheel imperfections, rail settlements, wear and tear and health assessment of railway bridges and tunnels will be thoroughly discussed.

A review of railway infrastructure monitoring using fiber optic sensors

Upgrading superior operation performance efficiency of submarine transceiver optical communication systems toward multi tera bit per second

Data communication systems are increasingly employing optical fiber communication systems (OFCS) as the transmission paths for information. Various types of optical amplifiers have been developed in OFCS to amplify optical signals. In particular, the Erbium-doped fiber amplifier (EDFA) is one example of an optical fiber amplifier that is widely known for use in amplifying optical signals. The most significant points in any optical amplifier design are gain and noise figure (NF). They are closely related to each other. Low NF and high gain are the main features for optimum amplifier (Desurvire, 1987). On the other hand, the gain and NF have very strong impact with EDFA’s configurations. Therefore, changes in EDFA’s configuration play very important role during the designing of optical amplifier. The literature shows that there is no study that has been done to review the EDF configuration. Therefore, in this paper we are presenting an overview of most of the EDFA’s configurations that have been proposed in order to provide the researchers with a clear view of what has been done in this field.

	 

	Key words: Communication system, optical amplifier, EDFA configurations, noise figure, gain amplifier, rare-earth doped fibers, atomic systems, EDFA’s position.

https://africaneditors.org/journal/IJPS/full-text-pdf/48934-114856

Review of Erbium-doped fiber amplifier

Temperature independent length optimization of L-band EDFAs providing flat gain

In this study, a fuzzy logic (FL)-based device is designed, constructed, and applied to a C band (1530–1565 nm) erbium-doped fiber amplifier to obtain maximum signal gain and appropriate erbium-doped fiber length for the temperature range between −20 and +60°C. The fuzzy rules—which are embedded into the circuit—are compiled using the input variables which are, namely, the signal wavelength and the temperature, whereas the output parameters are the signal gain and the appropriate fiber length providing the maximum signal gain. The FL-based device provides the predictions for the fiber length providing the maximum signal gain against the input signal wavelength, and the temperatures within the accuracy level of 95–99%. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2331–2334, 2008; Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.23699

A fuzzy logic based device for the determination of temperature dependence of EDFAs

Railway and train security are very important in preventing service disruption and ensuring quality and safe journeys. Conventional gauges are used in laboratory environments for the strain measure...

Real-time monitoring of railroad track tension using a fiber Bragg grating-based strain sensor

Determination of Minimum Temperature Coefficient of C Band EDFA

In this study, a Fiber Bragg Grating (FBG) based temperature sensor is designed. Simulation is conducted to observe FBG's response to the temperature change. The temperature incident on the FBG is gradually changed from 0°C to 60°C in 10°C steps and the frequency shifts in both RF and optical spectrum are observed.

Murat Yucel

Papers

Temperature independent length optimization of L-band EDFAs providing flat gain

A fuzzy logic based device for the determination of temperature dependence of EDFAs

Real-time monitoring of railroad track tension using a fiber Bragg grating-based strain sensor

Determination of Minimum Temperature Coefficient of C Band EDFA

Design of a Fiber Bragg Grating based temperature sensor