Fiber Optic Communications Lecture 2
Fiber Optic CommunicationsLecture 2 Fiber ModesSystem componentsModulationMultiplexing
Maxwell’s EquationsDivergence equationsCurl equations B E t D ρ B 0 D H J tFlux lines start and endon charges or polesChanges in fluxes give rise to fieldsCurrents give rise to H-fieldsNote: No constants such as μ0 ε0, μ ε, c, χ, . appear when written this wayThey are hidden in B and DFrom Maxwell’s Equations: Existence of EM waves(no need for charges, materials)HEEHE .Curl equations: Changing E-field results in changing H-field results in changing E- field .1/7/2019ECE 695 - Peter Bermel - Purdue University2
Wave EquationWave equation:2 1 U ( r, t )2 U ( r, t ) 2v t 2SOLUTION:Waves propagating witha (phase) velocity vU ( r , t ) Re {U 0 ( r ) exp ( iωt )}Position1/7/2019for E and HECE 695 - Peter Bermel - Purdue University3Time
Wave Equation in Vacuum2 1 U ( r, t )2 U ( r, t ) 2v t 21/7/2019ECE 695 - Peter Bermel - Purdue University4
Wave Equation: Cylindrical CoordinatesWave equation:for E and H1/7/2019ECE 695 - Peter Bermel - Purdue University5
Wave Equation: Cylindrical CoordinatesSolution:1/7/2019ECE 695 - Peter Bermel - Purdue University6
Fiber LossesLinear absorption:Stimulated Brillouin Scattering:Stimulated Raman Scattering:Self-Phase Modulation1/7/2019Cross-Phase ModulationECE 695 - Peter Bermel - Purdue University7
Group Velocity Dispersion1/7/2019ECE 695 - Peter Bermel - Purdue University8
Material Dispersion1/7/2019ECE 695 - Peter Bermel - Purdue University9
Limitations on Bit Rate1/7/2019ECE 695 - Peter Bermel - Purdue University10
Fiber Optic CommunicationsLecture 2 Fiber ModesSystem componentsModulationMultiplexing
Optical Telecommunications:Basic System nelOptical ReceiverOutputElectrical latorECE 695 - Peter Bermel - Purdue University12
Optical Telecommunications:Basic System itterPhotodetectorCommunicationChannelOptical ReceiverElectronicsECE 695 - Peter Bermel - Purdue UniversityOutputDemodulator13
Optical Telecommunications:Physical Components Source: Laser or LED Signal: information in the form of electrical signal – analog ordigital E/O: Modulator – modulates the light from source accordingto the signal Fiber: Optical fiber – multimode or single mode fibers OA: Optical amplifier – boost the intensity of light O/E: Photodetector – converts light to electricity Receiver: Extracts information from the received light1/7/2019ECE 695 - Peter Bermel - Purdue University14
Specific Communication SystemComponents by Channel1/7/2019ECE 695 - Peter Bermel - Purdue University15
Fiber Optic CommunicationsLecture 2 Fiber ModesSystem componentsModulationMultiplexing
Optical Modulation Information is coded in the light wave itself byoptical modulation Many modulation techniques– Field modulation– Intensity modulation– Pulse Code Modulation (PCM)– Frequency or Phase Shift Keying (PSK)1/7/2019ECE 695 - Peter Bermel - Purdue University17
Field ModulationModulation similar to microwave modulation: amplitude,frequency and phase modulationDifficult to implement with light: requires extremely stable laser source extreme coherence polarization controlled transmission heterodyne receiver1/7/2019ECE 695 - Peter Bermel - Purdue University18
Intensity Modulation Simple implementation LED or laser sources can be used WDM is implemented using this modulationscheme1/7/2019ECE 695 - Peter Bermel - Purdue University19
Pulse Code Modulation (PCM)Amplitude of the signal is proportional tonumber of pulses within each sample-period1/7/2019ECE 695 - Peter Bermel - Purdue University20
ON-OFF Keying (OOK)Frequency shift keying (FSK) and Phase Shift keying (PSK) are variants of OOK.1/7/2019ECE 695 - Peter Bermel - Purdue University21
Fiber Optic CommunicationsLecture 2 Fiber ModesSystem componentsModulationMultiplexing
Multiplexing Providing (dynamic) rerouting of channels Electronic multiplexing – signals from different channels are addedbefore optical modulation Optical multiplexing – signals from different channels are codedinto light before multiplexing Different schemes– Frequency Division Multiplexing (FDM)– Time Division Multiplexing (TDM)– Code Division Multiplexing (CDM)1/7/2019ECE 695 - Peter Bermel - Purdue University23
Multiplexing schemes FDM – each channel is assigned to a differentfrequency TDM – each channel is transmitted in a different timeinterval CDM – each channel is encoded differently1/7/2019ECE 695 - Peter Bermel - Purdue University24
Code Division Multiplexing Each channel is encoded differently usingdifferent keys. Decoding requires a key which selects only aparticular channel.1/7/2019ECE 695 - Peter Bermel - Purdue University25
Hierarchical multiplexing Multiplexing many channels together is oftenperformed in a hierarchy.1/7/2019ECE 695 - Peter Bermel - Purdue University26
Wavelength division multiplexing (WDM) Different channels are transmitted at differentoptical frequencies Multiplexer and demultiplexers are frequencyselective routers1/7/2019ECE 695 - Peter Bermel - Purdue University27
Wavelength Division MultiplexingAlso known asfrequency divisionmultiplexing (FDM).Each channel isassigned to adifferent frequencyband.Demultiplexing isperformed byspectral filtering.Minimum cross-talkbetween channels.1/7/2019ECE 695 - Peter Bermel - Purdue University28
MUX and DEMUX for WDM1/7/2019ECE 695 - Peter Bermel - Purdue University29
WDM Types Specifications Coarse WDM (CWDM) – channels are spacedwide apart (typical: 20 nm apart) Dense WDM (DWDM) – channels are closelyspaced, more channels can be transmitted Typical channel spacing: 25 to 100 GHz ( 0.2 to0.4 nm) DWDM requires extremely stable light source1/7/2019ECE 695 - Peter Bermel - Purdue University30
OADM (Optical Add-Drop Mux) Uses a multiplexer-demultiplexer pair Mux adds the signals, demux dropsone channel at each stage. One particular channel can beaccessed at each stage.Microring resonator basedFiber Bragg-grating based1/7/2019ECE 695 - Peter Bermel - Purdue University31
MZI demultiplexer Mach-Zehnder interferometer: light split into two pathsinterferes Output is high if the interference is constructive, low ifdestructive Constructive interference at one wavelength may be arrangedto produce destructive at the other wavelength1/7/2019ECE 695 - Peter Bermel - Purdue University32
Multiplexing Providing (dynamic) rerouting of channels Electronic multiplexing – signals from different channels are added before optical modulation Optical multiplexing – signals from different channels are coded into light before multiplexing Different schemes – Frequency Division Multiplexing (FDM)
Fiber optic termination - ModLink plug and play fiber optic solution 42 Fiber optic termination - direct field termination 42 Fiber optic termination - direct field termination: Xpress G2 OM3-LC connector example 43 Cleaning a fiber optic 45 Field testers and testing - fiber optic 48 TSB-4979 / Encircled Flux (EF) conditions for multimode fiber .
Nowadays fiber optic is one of the technologies used for structural and geotechnical monitoring projects. Fiber optic sensors are normally classified as point, multiplexed, long-base or distributed sensors. . D., "Fiber Optic Methods for Structural Health Monitoring", John Wiley & Sons, Ltd, 2007. 2. Inaudi, D., "Distributed Fiber Optic .
C A B L E B L O w i N ghand held Fiber Blower The Condux hand held fiber blower is ideal for shorter run fiber optic cable or micro fiber optic cable installations. The unit's hinged design makes it easy to install and remove duct and fiber. The Condux hand held fiber blower installs fiber from 0.20 inches (5.8 mm) to 1.13 inches (28.7 mm)
Figure 12: Construction of a Single Fiber Cable Figure 13: Example of the Construction of a Multi- Fiber Cable II.3 Connectivity Fiber optic links require a method to connect the transmitter to the fiber optic cable and the fiber optic cable to the receiver. In general, there are two methods to link optical fibers together. II.3.1 Fusion Splice
Introduction of Chemical Reaction Engineering Introduction about Chemical Engineering 0:31:15 0:31:09. Lecture 14 Lecture 15 Lecture 16 Lecture 17 Lecture 18 Lecture 19 Lecture 20 Lecture 21 Lecture 22 Lecture 23 Lecture 24 Lecture 25 Lecture 26 Lecture 27 Lecture 28 Lecture
Fiber Optic Infrastructure Application Guide ENET-TD003C-EN-P Deploying a Fiber Optic Physical Infrastructure within a Converged Plantwide Ethernet Architecture Fiber Optic Cabling Systems Overview Figure 3 Permanent Link Diagram The typical channel is composed of multiple assemblies connected by a combination of the optical fiber
The Condux Fiber Optic Cable Blower operates efficiently with most common combinations of cable and innerduct sizes. The Fiber Optic Cable Blower is designed for the installation of fiber optic cables with diameters from 0.23" (5.8 mm) to 1.13" (28.7 mm) into
Optimux-1553 STM-1/OC-3 Terminal Multiplexer Figure 3. Optimux-1553 Extending an SDH/SONET Network Towards Remote Customers Feature Optimux-4E1/4T1 Optimux-34 Optimux-XLT1 Optimux-45/45L Optimux-1551 Optimux-1553 Uplink Fiber Optic E3, Fiber Optic Fiber Optic T3, Fiber Optic Copper,
