Kyland-USA, Kansas City, MO DYMEC is a registered trademark of Kyland-USA

Kyland-USA, Kansas City, MO Kyland-USA Overview Kansas City, Missouri ECO-Engineering Company Veteran Owned Small Business Made in USA products Energy Conservation Focus on IP Industrial Security

Kyland-USA, Kansas City, MO DYMEC is a registered trademark of Kyland-USA Fiber Optic Fundamentals

Kyland-USA, Kansas City, MO Fiber Optics versus Copper Cabling Optical fiber transmits via light pulses Can be used for analog or digital transmission Voice, computer data, video, etc. Copper wires (or other metals) can carry the same types of signals with electrical pulses

Kyland-USA, Kansas City, MO The Advantage of Fiber Fiber has multiple advantages compared to metallic wires * Bandwidth – more data per second * Longer Distances * Lighter and Smaller (Less Bulk) * Faster Speeds – Terabyte Speeds Possible Applications such as medical imaging and quantum key distribution are only possible with fiber because they use light directly

Kyland-USA, Kansas City, MO Copper Wiring Tends to be Messy

Kyland-USA, Kansas City, MO Optical Fiber versus Copper

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 8 Fiber Optic Cable Structure Fiber is mechanically weak Cable adds protection and prevents physical damage during installation and use. Combination and quantity of protections and material as well as construction are strictly dependent on cable environment Indoor - Ducts - Trays - Building raiser - Plastic pipes - Raised floors - Plenum (US) Outdoor - Empty pipes - Ducts - Trays - Direct burial - Aerial

Kyland-USA, Kansas City, MO Connectivity and Interoperability Electrical Connector Electrical Connector SFP Transceiver Fiber Optic Cable LC Optical Connector LC Optical Connector Optical Port Optical Port Newer technologies involving higher datarates, smaller form factors, higher port densities, pluggability, and parallel links are showing an increased need to focus on connectivity and interoperability issues A failure anywhere along this link will cause the entire link to fail

Kyland-USA, Kansas City, MO Copper is Slower / Limited Distance What speed does each type support? Cable TypeMax SpeedMax DistanceCost Factor Category 5100Mbs100m1x Category 5e1000Mbs100m1x Category 61000Mbs100m1.3x Category 610,000Mbs57m1.3x Category 6a10,000Mbs100m2x

Kyland-USA, Kansas City, MO Elements of a Fiber Data Link Transmitter emits light pulses (LED or Laser) Connectors and Cables passively carry the pulses Receiver detects the light pulses TransmitterReceiver Cable

Kyland-USA, Kansas City, MO Fiber Repeaters For very long links, repeaters are needed to compensate for signal loss. Fiber = Optical Repeater = Electrical Result = OEO (Optical – Electrical – Optical) Fiber Repeater Fiber

Kyland-USA, Kansas City, MO Fiber Size & Aperture Comparisons

Kyland-USA, Kansas City, MO Optical Fiber Core Glass or plastic with a higher index of refraction than the cladding Carries the signal Cladding Glass or plastic with a lower index of refraction than the core Buffer Protects the fiber from damage and moisture Jacket Holds one or more fibers in a cable

Kyland-USA, Kansas City, MO Single-Mode Fiber Single-mode fiber has a core diameter of 8 to 9 microns, which only allows one light path or mode Index of refraction

Kyland-USA, Kansas City, MO Multi-Mode Step-Index Fiber Multimode fiber has a core diameter of 50 or 62.5 microns (sometimes even larger) Allows several light paths or modes This causes modal dispersion – some modes take longer to pass through the fiber than others because they travel a longer distance Index of refraction

Kyland-USA, Kansas City, MO Multi-Mode Graded-Index Fiber The index of refraction gradually changes across the core Modes that travel further also move faster This reduces modal dispersion so the bandwidth is greatly increased Index of refraction

Kyland-USA, Kansas City, MO Step Versus Graded Index Fiber Step index multi-mode was developed first, but rare today because it has a low bandwidth (50 MHz-km) It has been replaced by Graded-index multi-mode with a bandwidth up to 2 GHz-km

Kyland-USA, Kansas City, MO Plastic Optical Fiber Large core (1 mm) step-index multi-mode fiber Easy to cut and work with, but high attenuation (1 dB / meter) makes it useless for long distances

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 20 POF (Plastic Optical Fiber) Terminology Core Acrylic AcrylicGlass Cladding Fluorinated Polyperfluoro Fluorinated butenylvinylether PMMA PCF traditional perfluorinated PROCESS Plasma OVD draw extrusion extrusion

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 21 Index profiles PMMA Step Index core = Constant refractive index PMMA Graded Index Core = several layer of material with different refractive indexes Perfluorinated Polymer Graded index Core = parabolic index

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 22 Overview - POF (PMMA and Perfluorinated) Index profile Type of fiberCore ØNAAttenuationBandwidth SI-POF (PMMA) SI-POF low NA 980µm dB/km ~ 50 MHz. 100m ~ 100 MHz. 100m DSI-POF980µm0.3180dB/km~ 100 MHz. 100m GI-POF (PMMA) 980µm 500µm dB/km~1.5 GHz. 100m GI-POF (PF) 62.5/ / / dB/km~ 3 GHz. 100m

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 23 Step Index polymer Optical Fiber (SI-POF) Core Ø980 μm Cladding Ø 1000 μm Attenuation180 dB/km Bandwidth10 MHz. 100m (100 MHz. 100m) Wavelength650nm N.A.0.5 (Low N.A. 0.3) Typetight buffer Advantageeasy, fast and inexpensive connection technology Disadvantagehigh attenuation, low bandwidth

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 24 Multistep Index Plastic Optical Fiber (GI-POF) Core Ø900 μm Cladding Ø 1000 μm Attenuation180 dB/km Bandwidth100 MHz. km Wavelength650nm Cabletight buffer Advantageeasy, fast and inexpensive connection technology commercially available Disadvantagehigh attenuation

Kyland-USA, Kansas City, MO Fiber Optic Cables / Page 25 Graded Index Plastic Optical Fiber (GI-POF) Core Ø120 μm Cladding Ø 500 μm Attenuation50 dB/km Bandwidth1000 MHz*km Wavelength1330nm Cableloose buffer (extra strength members) Advantagelow attenuation, high bandwidth Disadvantagetermination, expensive, similar to GOF

Kyland-USA, Kansas City, MO Light Sources and Wavelengths Multimode fiber is used with: LED sources at wavelengths of 850 and 1300 nm for slower local area networks Lasers at 850 and 1310 nm for networks running at gigabits per second or more

Kyland-USA, Kansas City, MO Light Sources and Wavelengths Single-mode fiber is used with: Laser sources at 1300 and 1550 nm Bandwidth is extremely high, around 100 THz-km

Kyland-USA, Kansas City, MO Fiber Optic Specifications Attenuation Loss of signal, measured in dB Dispersion Blurring of a signal, affects bandwidth Bandwidth The number of bits per second that can be sent through a data link Numerical Aperture Measures the largest angle of light that can be accepted into the core

Kyland-USA, Kansas City, MO Attenuation and Dispersion These are fiber cable characteristics

Kyland-USA, Kansas City, MO Measuring Fiber Bandwidth The bandwidth-distance product in units of MHz ×km shows how fast data can be sent through a cable A common multimode fiber with bandwidth- distance product of 500 MHz × km could carry A 500 MHz signal for 1 km, or A 1000 MHz signal for 0.5 km From Wikipedia

Kyland-USA, Kansas City, MO Numerical Aperture If the core and cladding have almost the same index of refraction, the numerical aperture will be small This means that light must be shooting right down the center of the fiber to stay in the core

Kyland-USA, Kansas City, MO Fiber Types and Specifications

Kyland-USA, Kansas City, MO Popular Fiber Types At first there were only two common types of fiber 62.5 micron multimode, intended for LEDs and 100 Mbps networks There is a large installed base of 62.5 micron fiber 8 micron single-mode for long distances or high bandwidths, requiring laser sources Corning’s SMF-28 fiber is the largest base of installed fiber in the world

Kyland-USA, Kansas City, MO Gigabit Ethernet Requirements 62.5 micron multimode fiber did not have enough bandwidth for Gigabit Ethernet (1000 Mbps) LEDs cannot be used as sources for Gigabit Ethernet – they are too slow So Gigabit Ethernet used a new, inexpensive source: Vertical Cavity Surface Emitting Laser (VCSEL)

Kyland-USA, Kansas City, MO Multi-mode Fiber & VCSELs First came laser-rated 50 micron multi-mode Bandwidth 500 MHz-km at 850 nm Then came laser-optimized 50 micron multi-mode Bandwidth 2000 MHz-km at 850 nm Distinctive aqua-colored jacket Today – Aqua color is used by: 10 Gigabit Fiber Connections

Kyland-USA, Kansas City, MO DO NOT Mix Fiber Types You can’t mix single-mode and multi-mode fiber – you lose 20 dB at the junction (99% of the light!) Mixing 50 micron and 62.5 micron multi-mode is not as bad, but you lose 3 dB (half the power) which is usually unacceptable Use 50 micron multi-mode cable for longer distances versus 62.5 micron multi-mode.

Kyland-USA, Kansas City, MO Fiber Manufacturing

Kyland-USA, Kansas City, MO Three Primary Methods Modified Chemical Vapor Deposition (MCVD) Outside Vapor Deposition (OVD) Vapor Axial Deposition (VAD)

Kyland-USA, Kansas City, MO Modified Chemical Vapor Deposition (MCVD) A hollow, rotating glass tube is heated with a torch Chemicals inside the tube precipitate to form soot Rod is collapsed to crate a preform Preform is stretched in a drawing tower to form a single fiber up to 10 km long

Kyland-USA, Kansas City, MO Modified Chemical Vapor Deposition (MCVD)

Kyland-USA, Kansas City, MO Outside Vapor Deposition (OVD) A mandrel is coated with a porous preform in a furnace Then the mandrel is removed and the preform is collapsed in a process called sintering

Kyland-USA, Kansas City, MO Vapor Axial Deposition (VAD) Preform is fabricated continuously When the preform is long enough, it goes directly to the drawing tower

Kyland-USA, Kansas City, MO Fiber Drawing The fiber is drawn from the preform and then coated with a protective coating

Kyland-USA, Kansas City, MO Index of Refraction When light enters a dense medium like glass or water, it slows down The index of refraction (n) is the ratio of the speed of light in vacuum to the speed of light in the medium Water has n = 1.3 Light takes 30% longer to travel through it Fiber optic glass has n = 1.5 Light takes 50% longer to travel through it

Kyland-USA, Kansas City, MO Fiber Applications

Kyland-USA, Kansas City, MO Step-index Multi-mode Large core size, so source power can be efficiently coupled to the fiber High attenuation (4-6 dB / km) Low bandwidth (50 MHz-km) Used in short, low-speed datalinks Also useful in high-radiation environments, because it can be made with pure silica core

Kyland-USA, Kansas City, MO Graded-index Multi-mode Useful for “premises networks” like LANs, security systems, etc. 62.5/125 micron has been most widely used Works well with LEDs, but cannot be used for Gigabit Ethernet 50/125 micron fiber and VSELS are used for faster networks

Kyland-USA, Kansas City, MO Single-mode Fiber * Best for high speeds and long distances Used by telephone companies and CATV Used Outdoors & Between Buildings

Kyland-USA, Kansas City, MO Fiber Performance

Kyland-USA, Kansas City, MO Attenuation Modern fiber material is very pure, but there is still some attenuation The wavelengths used are chosen to avoid absorption bands 850 nm, 1300 nm, and 1550 nm Plastic fiber uses 660 nm LEDs

Kyland-USA, Kansas City, MO The 3 Types of Dispersion Dispersion is the spreading out of a light pulse as it travels through the fiber Three types: Modal Dispersion Chromatic Dispersion Polarization Mode Dispersion (PMD)

Kyland-USA, Kansas City, MO Modal Dispersion Spreading of a pulse because different modes (paths) through the fiber take different times Only happens in multimode fiber Reduced, but not eliminated, with graded-index fiber

Kyland-USA, Kansas City, MO Chromatic Dispersion Different wavelengths travel at different speeds through the fiber This spreads a pulse in an effect named chromatic dispersion Chromatic dispersion occurs in both singlemode and multimode fiber Larger effect with LEDs than with lasers A far smaller effect than modal dispersion

Kyland-USA, Kansas City, MO Polarization Mode Dispersion Light with different polarization can travel at different speeds, if the fiber is not perfectly symmetric at the atomic level This could come from imperfect circular geometry or stress on the cable, and there is no easy way to correct it It can affect both single-mode and multi-mode fiber.

Kyland-USA, Kansas City, MO Modal Distribution In graded-index fiber, the off-axis modes go a longer distance than the axial mode, but they travel faster, compensating for dispersion But because the off-axis modes travel further, they suffer more attenuation

Kyland-USA, Kansas City, MO Equilibrium Modal Distribution A long fiber that has lost the high-order modes is said to have an equilibrium modal distribution For testing fibers, devices can be used to condition the modal distribution so measurements will be accurate

Kyland-USA, Kansas City, MO Mode Stripper An index-matching substance is put on the outside of the fiber to remove light travelling through the cladding

Kyland-USA, Kansas City, MO Mode Scrambler Mode scramblers mix light to excite every possible mode of transmission within the fiber Used for accurate measurements of attenuation

Kyland-USA, Kansas City, MO Mode Filter Wrapping the fiber around a 12.5 mm mandrel Exceeds the critical angle for total internal reflection for very oblique modes The high-order modes leak into the cladding and are lost That creates an equilibrium modal distribution Allows an accurate test with a short test cable

Kyland-USA, Kansas City, MO Decibel Units

Kyland-USA, Kansas City, MO AKA – Poor Mans Attenuator Wrapping the fiber around a 12.5 mm mandrel Or wrapping fiber in a tight circle such as your hand – cuts down the light (or hot signal) down to acceptable receiver levels – preventing Receiver Saturation / Link Loss.

Kyland-USA, Kansas City, MO Optical Loss in dB (decibels) If the data link is perfect, and loses no power The loss is 0 dB If the data link loses 50% of the power The loss is 3 dB, or a change of – 3 dB If the data link loses 90% of the power The loss is 10 dB, or a change of – 10 dB If the data link loses 99% of the power The loss is 20 dB, or a change of – 20 dB dB = 10 log (Power Out / Power In) Data Link Power In Power Out

Kyland-USA, Kansas City, MO Absolute Power in dBm The power of a light is measured in milli-watts For convenience, we use the dBm units, where -20 dBm = 0.01 milli-watt -10 dBm = 0.1 milli-watt 0 dBm = 1 milli-watt 10 dBm = 10 milli-watts 20 dBm = 100 milli-watts

Kyland-USA, Kansas City, MO Construction Hints For cable installed in underground conduit: No more than 200m between pull points Reduce distance by 50m for every 90 degrees of bend

Kyland-USA, Kansas City, MO Fiber Optic Cable Construction Leave slack loops

Kyland-USA, Kansas City, MO DYMEC is a registered trademark of Kyland-USA THANK YOU !