Due to rapidly growing technological trends higher data rate support has become the key feature in future communication medium selection. Multi-mode optical fiber cable and Multi-core optical fiber is well matched for high data rate throughput requirements due to its tendency to support multiple modes through one core at a time which results in to higher data rates. But with multi-mode modal dispersion, crosstalk is the main limiting factor.
So in this research work we have investigated the fiber design parameters core diameter (µm), Wavelength (nm), refractive index profile to achieve Few mode fiber , their number of channels, curves of group delay, material losses , Bending losses , PMD and effective Nonlinear Refractive Index for each guided mode. Space Division Multiplexing is promising future technology which uses few mode fiber in parallel to form multicore fiber.
This research work also includes the calculation of radial distance, guided modes and there losses through 12 cores single mode fiber. Then designed a 12 cores few mode fiber with different refractive index and core diameter. These tests are done on standard 2nd window wavelength 1550 µm. Simulations and results of different designs according to standard area of 125µm have been presented in this thesis. Conclusion of this research is we can design concentric cores single mode fiber (CCSMF) up-to 4 layers within 125 µm , and can enhance bandwidth of fiber. Concentric core Fiber can be used for military purpose i.e. inner core can be used for message signal whereas outer cladding will keep alarm signal in it.
Table of Contents
1 INTRODUCTION
1.1 HISTORY OF COMMUNICATION SYSTEMS
1.1.1 Usage of Glass Material
1.1.2 Advent of Optical Fiber
1.2 PROBLEM STATEMENT
1.3 PROPOSED WORK
1.4 ORGANIZATION OF THESIS
2 LITERATURE REVIEW
2.1 SPACE DIVISION MULTIPLEXING
2.1.1 Approaches to Execute SDM
2.2 SINGLE MODE FIBER (SMF)
2.2.1 Multi-Core Single Mode Fiber (MC-SMF)
2.3 MULTI-MODE FIBER (MMF)
2.4 MULTI CORE FIBERS (MCF)
2.4.1 Collected work on MCF
2.5 FEW MODE FIBER (FMF)
2.5.1 Motivation behind FMF
2.5.2 Few-Mode Fiber Manufacturing
2.5.3 Literature of FMF
2.5.4 Classes of Few-Mode Fiber Devices
3 DEFINITION, GENERATION AND SHAPES OF LINEAR POLARIZED MODES
3.1 OPTICAL FIBER
3.2 FIBERS MODES
3.2.1 Standard Description
3.2.2 Linearly polarized (LP) mode
3.3 TYPES OF MODES
3.3.1 Guided Modes
3.3.2 Radiation Modes
3.3.3 Leaky Modes
3.4 MAXWELL’s EQUATIONS
3.4.1 Interpretation of Maxwell’s Equations
3.5 Some important parameters of LP modes are as follows:
3.5.1 Phase Velocity
3.5.2 Group Velocity
3.5.3 Group Velocity Dispersion
3.6 V-PARAMETER
3.6.1 Single-Mode Fiber V < 2.4
3.6.2 Multi-Mode Fiber V≥2.4
4 DESIGN AND NUMERICAL MODELING OF 12 CORES SINGLE MODE FIBER
4.1 Specify Fiber Parameters
4.2 Fiber Profile
4.3 Dispersion
4.4 MATERIAL DISPERSION
4.5 Waveguide dispersion of the fiber
4.6 Total dispersion of the fiber
4.7 Material Losses
4.7.1 OH-radical absorption model
4.7.2 Infrared absorption model
4.8 Confinement Diagram of some modes
4.8.1 Linear Polarized Mode LP(01)
4.8.2 Linear Polarized Mode LP(02)
4.8.3 Linear Polarized Mode L P(11)
4.8.4 Linear Polarized Mode LP (21)
4.8.5 Linear Polarized Mode LP (3, 2)
4.9 Mode Field
4.9.1 Linear Polarized LP ( 0 , 1)
4.9.2 Linear Polarized LP ( 0 , 2)
4.9.3 Linear Polarized LP ( 1,1)
4.9.4 Linear Polarized (3,2)
4.10 Polarization Mode Dispersion ( PMD)
4.11 Effective Nonlinear Refractive Index
5 DESIGN OF 12 CORES FEW MODE FIBER AND ANALYSIS OF GRAPHS
5.1 Design Parameters
5.2 Fiber Profile
5.3 Dispersion
5.4 Material Losses
5.5 Confinement Diagram of some modes
5.5.1 Linear Polarized Mode LP (01)
5.5.2 Linear Polarized Mode LP (02)
5.5.3 Linear Polarized Mode LP (11)
5.5.4 Linear Polarized Mode LP (21)
5.5.5 Linear Polarized Mode LP (31)
5.5.6 Linear Polarized Mode LP (41)
5.5.7 Linear Polarized Mode LP (5,1)
5.6 Bending Loss
5.7 Polarization Mode Dispersion
5.8 Effective Nonlinear Refractive Index
6 RESULTS AND SIMULATION
6.1 cores concentric fiber
6.1.1 Fiber profile
6.1.2 Eff. And Group Indices Versus Wavelength [µm]
6.1.3 Group Delay
6.1.4 Dispersion
6.1.5 Material Loss
6.1.6 Confinements of some important channels
6.1.6.1 Linear Polarized (01)
6.1.6.2 Linear Polarized (02)
6.1.6.3 Linear Polarized (11)
6.1.6.4 Linear Polarized (21)
6.1.6.5 Linear Polarized 22
6.1.6.6 Linear Polarized (31)
6.1.6.7 Linear Polarized (51)
6.1.7 Mode Field Area
6.1.7.1 MDF of LP(0,2)
6.1.7.2 MDF of LP(0,2)
6.1.7.3 MDF LP (0,4)
6.1.7.4 MDF LP(1,1)
6.1.7.5 MDF LP(2,1)
6.1.7.6 MDF LP(2,2)
6.1.7.7 MDF LP (3,1)
6.1.7.8 MDF LP(4,4)
6.1.7.9 MDF LP(5,1)
6.1.8 Bending Losses
6.1.9 PMD
6.1.10 Non-Linear Refractive index
6.2 Patent Design upto 3 cores
6.2.1 Fiber profile
6.2.2 Material Losses
6.2.3 Dispersion
6.2.4 Confinement Diagram of different modes
6.2.4.1 Linear Polarized 01
6.2.4.2 Linear Polarized 02
6.2.4.3 Linear Polarized 11
6.2.4.4 Linear Polarized (21)
6.2.5 Mode Field Area OF SOME IMPORTANT MODES
6.2.5.1 MDF LP (1,1)
6.2.5.2 MDF LP (2,2)
6.2.6 Polarized Mode Dispersion (PMD)
6.3 COMPARISON BETWEEN 12 CORES SMF AND 12 CORES FMF
6.4 COMPARISON BETWEEN 2 CORES FIBER AND 3 CORES CONCENTRIC FIBER
7 CONCLUSION & FUTURE WORK
7.1 CONCLUSION
7.2 FUTURE WORK
8 References
Objectives and Topics
The primary objective of this research is to analyze and design multi-core and few-mode optical fibers to overcome the capacity crunch in current communication systems. By investigating fiber design parameters such as core diameter, refractive index, and wavelength, the study explores how to maximize data transmission capacity and improve bandwidth through space-division multiplexing (SDM) techniques.
- Space Division Multiplexing (SDM) and its implementation in modern optical networks.
- Design and numerical modeling of 12-core single-mode and few-mode fibers.
- Analysis of fiber performance parameters: dispersion, material loss, confinement, and PMD.
- Investigation of concentric core fiber designs for military and high-capacity communication applications.
- Comparison between different fiber architectures (12-core vs. 3-core configurations).
Extract from the Book
1.1 HISTORY OF COMMUNICATION SYSTEMS
The use of light for communication dates back to ancient times if we interpret optical communications in a broad sense [1]. Utmost Civilizations have used mirrors, Fire, beacons and smoke signals to convey a single piece of information (such as victory in a War). The same ideas was been used till the end of eighteen century through signaling lamps, flags and other semaphores devices [2]. Communication between humans can be divided into two different categories by analyzing the evolution and the consequences of communication through history [3].
The Advent of telegraphy in the 1830s replaced the use of light by electricity and it was the opening of electricity communication era. By the use of coding techniques such as Morse code, the Bit Rate B could be increased to approx. 10b/s over long distances 1000 km. the First successful transatlantic telegraph cable went into operation in 1866.
Summary of Chapters
1 INTRODUCTION: This chapter introduces the evolution of communication systems, the problem statement regarding the data capacity limit, and the goals of the research.
2 LITERATURE REVIEW: This chapter provides a comprehensive background on Space Division Multiplexing, single-mode fibers, multi-mode fibers, and few-mode fibers.
3 DEFINITION, GENERATION AND SHAPES OF LINEAR POLARIZED MODES: This chapter covers fundamental theoretical aspects, including Maxwell's equations and the physics of fiber modes.
4 DESIGN AND NUMERICAL MODELING OF 12 CORES SINGLE MODE FIBER: This chapter details the research methodology and the simulation of 12-core single-mode fiber designs.
5 DESIGN OF 12 CORES FEW MODE FIBER AND ANALYSIS OF GRAPHS: This chapter presents the design parameters and performance results for 12-core few-mode fibers.
6 RESULTS AND SIMULATION: This chapter details the findings on concentric core fiber designs and provides a performance comparison between different fiber architectures.
7 CONCLUSION & FUTURE WORK: This chapter summarizes the research achievements and provides insights into potential future enhancements for optical network implementation.
Keywords
Space Division Multiplexing, Optical Fiber, Multi-core Fiber, Few-mode Fiber, Data Transmission, Modal Dispersion, Polarization Mode Dispersion, Refractive Index, Bandwidth, Crosstalk, Single-mode Fiber, Numerical Modeling, Optical Communication, Fiber Design, MIMO DSP.
Frequently Asked Questions
What is the primary motivation for this research?
The primary motivation is the exponential growth in demand for data transmission capacity, which is causing traditional single-mode fibers to hit their physical transmission limits, often referred to as the "limit crunch."
What are the main topics covered in this thesis?
The thesis covers Space Division Multiplexing (SDM), the design and modeling of multi-core and few-mode fibers, analysis of fiber dispersion and loss, and a comparison of performance across different fiber designs.
What is the primary research goal?
The research aims to design and numerically analyze high-capacity fibers, specifically 12-core single-mode and few-mode fibers, to enhance bandwidth using space-division multiplexing techniques.
Which scientific software is used for the simulation?
The research utilizes the "OptiFiber" tool, which is a numerical mode solver and simulation software specifically designed for planning and testing optical links.
What is the core focus of the analysis in the main chapters?
The analysis focuses on fiber parameters such as core diameter, refractive index profiles, mode confinement, material losses, polarization mode dispersion (PMD), and nonlinear refractive indices.
What defines the research's main keywords?
The research is characterized by terms related to advanced optical networking, specifically Space Division Multiplexing, Fiber Design, and high-speed data transmission technologies.
What is the significance of "Concentric Core Fibers"?
Concentric core fibers are proposed as a novel design, potentially useful for military purposes, where the inner core can carry sensitive message signals while the outer cladding or secondary cores handle auxiliary signals.
How does the author compare 12-core SMF and FMF?
The author presents a comparative table (Table 6-1) evaluating parameters like core area, number of modes, group delay, dispersion, and nonlinear refractive indices at a 1550 nm wavelength.
What conclusion does the author reach regarding fiber capacity?
The author concludes that designing fibers with multiple cores and supporting multiple modes simultaneously is a promising solution to satisfy high-data-rate requirements for future communication networks.
- Quote paper
- Iram Nadeem (Author), 2017, Simulation Analysis of Multicore Concentric Fibers by Space Division Multiplexing, Munich, GRIN Verlag, https://www.grin.com/document/359277
