Training_Passive components_GB Page 1 Passive components September 2013

Training_Passive components_GB Page 2 Definition Passive components are used to transmit signals to an end customer without integrating active components within a channel. Application: mainly in single mode Point to Multi-point application. Function Light attenuation Light filtering Light coupling Light splitting

Training_Passive components_GB Page 3 Overview passive optical components Terminator Attenuator Coupler/Splitter Multiplexer und de-multiplexer (WDM) Filter Isolator Passive dispersion compensator Connection Splice Fiber

Training_Passive components_GB Page 4 Coupler/Splitter and xWDM ONT: Optical Network Termination Street cabinet (FTTC) Apartment (FTTH) Splitters: Splitting in blocks, Street, building WDM: Multiplexer e.g. Triple Play 1490nm,1310nm nm OLT: Optical Line Termination (im CO) Attenuator, Terminator: everywhere where fibers are unused

Training_Passive components_GB Page 5 Attenuator Terminator

Training_Passive components_GB Page 6 Attenuator Application Adaption of the transmitted light power to the dynamic range of the receiver. Prevention of over amplification of the receiver Installation between adapter and patch cord Metal doped fiber P in P out

Training_Passive components_GB Page 7 Attenuations (SM) Characteristics Balancing the channel power in wave division multiplexing system Variable- and fixed value attenuatiors male-side female-side

Training_Passive components_GB Page 8 Terminator Characteristic Limitation of return loss on open and unused connector/adapter Reduction of reflected light thanks to doped fiber in terminator. Prevention of disturb signal by reflected light metal doped fiber P in optical power converted in heat.

Training_Passive components_GB Page 9 Terminator Application unused channels in telecommunication distribution panels measuring devices CATV installations, in order to have a stable and lower back reflection in the system.

Training_Passive components_GB Page 10 Einsatz von Terminator (SM) Open connectors in an installation: Open PC (0°) polished connector generates a RL of 14.7 dB (~ 3.5 % of optical power is reflected back) causing damage: in lasers amplifiers and other active components Terminator prevents back scattering from open ports. Terminator (open end) Coupler Transmitter (Laser, amplifier) Receiver

Training_Passive components_GB Page 11 Splitter/Coupler/WDM - General 2011

Training_Passive components_GB Page 12 Coupler/Splitter/WDM Principle splitting and coupling of optical signals Power- or wavelength depending (WDM) Requirements Low insertion loss high cross talk - and return loss high insulation small dimension high thermal and mechanical stability

Training_Passive components_GB Page 13 Technologies Various technologies are available for the coupler and splitter designs: SplitterWDM Fiber-based - Fused biconic tapered (FBT) fiber Waveguides based on planar lightwave circuit (PLC) Thin-film filter (TFF) Gratings Bulk optical (BOG) Fiber Bragg (FBG) Splitters can be packaged in different shapes and sizes, depending on the basic technology used.

Training_Passive components_GB Page 14 Technologies varied production methodology for splitter and coupler: Fiber based Fused biconic tapered (FBT) Wafer based Planar lightwave circuit (PLC) Form of packing and size depending on production method

Training_Passive components_GB Page 15 Technology and structure Planar lightwave circuit (PLC) Silicon substrate optical circuit typically high split counts (1x64) Fused biconical taper (FBT) fiber coupler thermally fused typically low counts (1x4)

Training_Passive components_GB Page 16 Naming of coupler/splitter based on arrangement Structure 1x2 Y-coupler 2x2 X-coupler 1xN tree coupler MxN star coupler Structure of splitter and coupler

Training_Passive components_GB Page 17 Variants 1x2, 2x2, 1x4, 2x4, 4x4…..2x128. Splitter are commonly cascaded with 1x2 or 2x2 splitter Coupler/Splitter Differences of splitter types varies on production method resp. further characteristics such as attenuation, uniformity etc.

Training_Passive components_GB Page 18 Configuration and platform

Training_Passive components_GB Page 19 Splitter and coupler 2011

Training_Passive components_GB Page 20 Splitter Coupler = Splitter ≠ xWDM 1310nm+1550nm 17dBm/50mW 1310nm+1550nm 13.5dBm/22.5mW 1310nm+1550nm 13.5dBm/22.5mW 3dB+0.5dB (3dB=50%) Function Splitting and coupling of optical signal Power division

Training_Passive components_GB Page 21 FBT - Fused Biconical Taper When twisting and fusing two fibers at the same time a coupling zone gets generated. One fiber is so called the reference fiber while the second one gets twisted around until the desired coupling ratio is achieved.

Training_Passive components_GB Page 22 FBT - Fused Biconical Taper CriteriaCharacteristic Wavelength 1 or 2 wave length with restricted tolerance band typical nm ±40nm Dimension large spliced size cm Attenuationup to a splitting ration 1x8 both types are similar Price1x2 ~ €10

Training_Passive components_GB Page 23 PLC - Planar Lightwave Circuit Ribbon or single fiber get s attached to the wafer. These fibers are meant to be assembled (connector) or spliced. The power split is ensured by Y-junction (Ion- exchange) fabricated inside the bulk material using photolithography technique

Training_Passive components_GB Page 24 PLC - Planar Lightwave Circuit CriteriaCharacteristic Wavelengthall optical (SM) windows Dimension small cascading on waver size from 10-20mm Attenuationfar better than FBT Price1x2 ~ €30-40 (from 1x8 cheaper)

Training_Passive components_GB Page 25 Terms we should know Directivity: Amount of reflected light in the parallel running fiber on the same side caused by the splitter [dB] Insertion loss: Loss in the splitter due signal splitting and splice losses [dB] Return loss: Amount of light reflected at the connector as well as in the splitter [dB] Uniformity: Difference of the highest attenuation at all split fibers at all wavelength [dB] Polarization Depending Loss : max. allowed variation in dependency of the polarization of the coupled light [dB]

Training_Passive components_GB Page 26 xWDM 2011

Training_Passive components_GB Page 27 xWDM 1310nm+1550nm 17dBm/50mW (pro λ) 1310nm 16dBm/40mW (pro λ) 1550nm 16dBm/40mW (pro λ) 1dB Coupler = Splitter ≠ xWDM Function Splitting and coupling of optical signal Wavelength division

Training_Passive components_GB Page 28 Function BWDM / CWDM / DWDM the principle of a fist class WDM‘s is according to the physical principle of light refraction. The longer a wave (λ) the less the refraction. Therefore all kind of WDM’s contain an element to split colors/frequencies. this principle works with some little exception bidirectional.

Training_Passive components_GB Page 29 Function BWDM / CWDM / DWDM

Training_Passive components_GB Page 30 xWDM - terms BWDMBroad Wavelength Division Multiplexing CWDMCoarse Wavelength Division Multiplex Application: Metropolitan Area Network DWDMDense Wavelength Division Multiplex Application: Wide- and Global Area Network Generally there are three different types: Other types such as Add/Drop WDM are application specific and based on the same technology

Training_Passive components_GB Page 31 FBT - WDM / CWDM / DWDM Fused Biconical Taper (FBT) Similar process as for coupler/splitter. Due to the different mode field diameter one wavelength couples out. unutilized the wavelength dependency on the mode field Ø by increasing the wavelength the mode Ø increases too. Low cost Low insertion loss Low isolation Broad passband

Training_Passive components_GB Page 32 Thin Film Filters (TFF) TFF‘s are coated with multiple layers of material that is manufactured using an ion-assisted physical vapor deposition. Each layer contains the property of a different refractive index. Particular wavelength are reflected or transmitted. TFF - WDM / CWDM / DWDM Low insertion loss High isolation Low PMD High Return Loss To a limited extent applicable for DWDM

Training_Passive components_GB Page 33 Fiber Bragg Gratings (FBG) Based on the principles of diffraction and of optical interference. When a polychromatic light source impinges on a diffraction grating, each wavelength is diffracted at a different angle and therefore to a different point in space. Using a lens, these wavelengths can be focused onto individual fibers FBG - WDM / CWDM / DWDM Under the first CWDM/DWDM High Insertion Loss High costs High dispersion

Training_Passive components_GB Page 34 Arrayed waveguide gratings (AWGs) Based on diffraction principles. An AWG device consists of an array of curved-channel waveguides with a fixed difference in the path length between adjacent channels. The process results in different wavelengths having maximal interference at different locations, which correspond to the output ports. AWG - WDM / CWDM / DWDM Narrow passband DWDM applicable Low dispersion High costs High PDL

Training_Passive components_GB Page 35 Development of WDM Systems BWDM2 channels 1310nm and 1550 nm CWDMmax. 18 channels 20nm spacing 1 carrier / window DWDMmax channels GHz spacing 1 carrier / window

Training_Passive components_GB Page 36 BWDM / CWDM / DWDM BWDM:Multiplexing with 2 wavelength (mainly 1310nm/1550nm), also called WWDM (Wide WDM) CWDM:Multiplexing up to 16 wavelengths (20nm channel spacing between 1260nm and 1650nm) DWDM:Multiplexing up to 160 wavelengths (1.6nm [200GHz], 0.8nm [100GHz] and 0.4nm [50GHz] channel spacing)

Training_Passive components_GB Page 37 Split in various wavelength (λ) – Multiplexing (MUX) Principle BWDM / CWDM / DWDM Combine various wavelength (λ) – Demultiplexing (DEMUX)

Training_Passive components_GB Page 38 Broad Wave Division Multiplexing BWDM Standard channel plan 2 wavelength 1310nm und 1550nm

Training_Passive components_GB Page 39 Course Wave Division Multiplexing CWDM Standard channel plan developed by Int. Telecommunications Union (ITU) 20 nanometer spacing between channels Starting at 1270nm and going thru 1610nm 18 Channels

Training_Passive components_GB Page 40 CWDM - characteristics CWDMCoarse Wavelength Division Multiplex Frequency range Frequency space20nm Number of Channel18 Lasercost effective thanks to rough frequency space Filtercheap, simple Data rate10Gbit/s per channel Optical amplifyingfrom 70 km Chromatic Dispersionfrom 10Gbit/s

Training_Passive components_GB Page 41 DWDM Standard channel plan developed by the ITU International Telecommunications Union 400, 200, 100, and now 50 GHz spacing between channels Starting at 1530nm and going thru 1560nm Dense Wave Division Multiplexing

Training_Passive components_GB Page 42 DWDM - characteristics DWDMDense Wavelength Division Multiplex Frequency range nm (C or L-Band) Frequency space0.4 – 4.6nm Lasertemperature- and wavelength stabilities Filterhochwertig Data rate10-100Gbit/s per channel for up to 80 respectively 160 channels Optical amplifyingafter km el. data regenerationafter km chromatic Dispersionfrom 10Gbit/s Polarizationmodedispersionfrom 40Gbit/s

Training_Passive components_GB Page 43 WDM / CWDM / DWDM Common types in our market environment: WDM 1310/1550nm (FBT or TFF) 4 / 8 channel CWDM (TFF) 4+1 channel Mux/deMux (TFF) 1490,1510, 1530, 1550nm+1310nm according ITU-T G recommendation (2 reserve channels) 8+1 channel Mux/deMux nm+1310nm (TFF)

Training_Passive components_GB Page 44 Pass-band: also called Pass channel wavelength. Spectrum of wavelength a WDM operates respectively is optimized. Pass-band ripple: Tolerance value of the attenuation variation within the pass-band. Isolation: Indicates the amount of ‘wrong’ wavelength/frequency carried in the fiber. A WDM for 1310nm with 17dB isolation may carry up to ~2% of e.g. 1550nm. Terms we should know

Training_Passive components_GB Page 45 Single mode band BandDescriptionWavelength range O-BandOriginal1260–1360 nm E-BandExtended1360–1460 nm S-BandShort wavelength1460–1530 nm C-BandConventional1530–1565 nm L-BandLong wavelength1565–1625 nm U-BandUltralong wavelength1625–1675 nm