Dwdm overview pdf

The OADM drops only the red optical signal stream. The dropped signal stream is passed to the receiver of a client device. The remaining optical signals that pass through the OADM are multiplexed with a new add signal stream. The OADM adds a new red optical signal stream, which operates at the same wavelength as the dropped signal. The new optical signal stream is combined with the pass-through signals to form a new composite signal.

Both of them can be found on the market now. Optical amplifiers boost the amplitude or add gain to optical signals passing on a fiber by directly stimulating the photons of the signal with extra energy.

They are "in-fiber" devices. Optical amplifiers amplify optical signals across a broad range of wavelengths. This is very important for DWDM system application. Transponders convert optical signals from one incoming wavelength to another outgoing wavelength suitable for DWDM applications.

A transponder performs an O-E-O operation to convert wavelengths of light, thus some people called them "OEO" for short. The figure below shows bi-directional transponder operation. From left to right, the transponder receives an optical bit stream operating at one particular wavelength nm.

The transponder converts the operating wavelength of the incoming bitstream to an ITU-compliant wavelength. It transmits its output into a DWDM system. On the receive side right to left , the process is reversed. The transponder receives an ITU-compliant bitstream and converts the signals back to the wavelength used by the client device.

Transponders are generally used in WDM systems 2. As a DWDM system is composed of these five components, how do they work together? The following steps give out the answer also you can see the whole structure of a fundamental DWDM system in the figure below :. The transponder accepts input in the form of a standard single-mode or multimode laser pulse. The input can come from different physical media and different protocols and traffic types.

The wavelength of the transponder input signal is mapped to a DWDM wavelength. DWDM wavelengths from the transponder are multiplexed with signals from the direct interface to form a composite optical signal which is launched into the fiber.

A post-amplifier booster amplifier boosts the strength of the optical signal as it leaves the multiplexer. An OADM is used at a remote location to drop and add bitstreams of a specific wavelength. Additional optical amplifiers can be used along the fiber span in-line amplifier as needed. A pre-amplifier boosts the signal before it enters the demultiplexer. Explore Documents. Uploaded by Rishi Nandwana. Did you find this document useful?

Is this content inappropriate? Report this Document. Flag for inappropriate content. Download now. Related titles. Carousel Previous Carousel Next. Understanding School Safety for Transgender Students. Jump to Page. Search inside document. Optical Fundamentals , Cisco Systems, Inc. Fiber Geometry Core Cladding An optical fiber is made of three sections: The core carries the light signals The cladding keeps the light in the core The coating protects the glass Coating , Cisco Systems, Inc.

Propagation in Fiber n2 q0 n1 q1 Intensity Profile Cladding Core Light propagates by total internal reflections at the core-cladding interface Total internal reflections are lossless Each allowed ray is a mode , Cisco Systems, Inc. Dispersion Compensating Fiber Dispersion Compensating Fiber: By joining fibers with CD of opposite signs polarity and suitable lengths an average dispersion close to zero can be obtained; the compensating fiber can be several kilometers and the reel can be inserted at any point in the link, at the receiver or at the transmitter , Cisco Systems, Inc.

ITU Wavelength Grid Why DWDM? The Technical Argument DWDM provides enormous amounts of scaleable transmission capacity Unconstrained by speed of available electronics Subject to relaxed dispersion and nonlinearity tolerances Capable of graceful capacity growth , Cisco Systems, Inc. Optical Filter Technology Dielectric Filter 1,2,3, Transmission Errors Errors happen! ATM 2. Transmission Effects Attenuation: Reduces power level with distance Dispersion and nonlinear effects: Erodes clarity with distance and speed Noise and Jitter: Leading to a blurred image , Cisco Systems, Inc.

Uni Versus Bi-directional DWDM DWDM systems can be implemented in two different ways Uni-directional: wavelengths for one direction travel within one fiber two fibers needed for full-duplex system 1 3 5 7 2 4 6 8 Fiber 2 4 6 8 1 3 5 7 Fiber Uni -directional Bi-directional: a group of wavelengths for each direction single fiber operation for fullduplex system , Cisco Systems, Inc.

Link Distance vs. Aman jai. Muhammad Sajid Saeed. Gender Spectrum. Ponce Livio. Kalyan Ghosh. Gunjan Garg. Ekjon Dipto. Ninz Taruc.

Norhamizah Ahmad Jailani. Asmit Upadhyay. Kathy Mcdonald. Nazmul Huda. Savu Daniel. When the input power is not so large, fiber has linear characteristics, when optical amplifier and high power laser amplifier used in optical fiber, the fiber nonlinear characteristic becoming significant;.

Using fiber that with mode field diameter, can inhibit the nonlinear effect. The most important thing is we can reduce the input power of fiber, use the large effective area fiber to prevent the happening of the nonlinear effect. The nonlinear effect is related to dispersion, dispersion is not the smaller the better.

When the energy density is too large, will cause the nonlinear effect of fiber, caused the system signal-to-noise ratio reduced, greatly affect the system performance. Thinking: This value is the larger the better, or the smaller the better? Is 3 dB a very large number? Why G. DCM M. A C A A 2x 2x. B OTU is Tunable, because each port of. S nodes, compared with back to back OTM node the complex artificial jump fiber can B ITL04 A C A.

B connected to a specific direction. So it can realize reroute. MRx board will node expansion interrupt the services? OA Input optical signal Amplified optical signal. Transmitting Transmitting L1 km L2 km. Fast in Fast in propagation propagation Direction of propagation fiber. Slow in propagation Slow in propagation Delay time. Detector power Signal response Polarization Mode Dispersion. PMD induced factors are randomly generated , which is a random polarization-mode dispersion and the quantity is difficult to compensate.

Signal DGD 1. BPSK 30 3, Optical Power dBm Psignal. Distance km. G fiber uses -5 dBm or -7dBm input power. Why does the output power of single wavelength decrease when the quantity of the channels increases? Why is G system just the opposite? What are relevant to OSNR of single amplifier or multi-amplifiers? A redundant bit may be a complex function of many original information bits. The original information may or may not appear literally in the encoded output; codes that include the unmodified input in the output are systematic, while those that do not are non-systematic.

Direction B Direction C Contentionless Gridless. MS-OTN board. All Rights Reserved. The information in this document may contain predictive statements including, without limitation, statements regarding the future financial and operating results, future product portfolio, new technology, etc.