Wavelength-division multiplexing

About: Wavelength-division multiplexing is a research topic. Over the lifetime, 25059 publications have been published within this topic receiving 332027 citations. The topic is also known as: WDM.

Communications network for a metropolitan area

Abstract: A communications network for a metropolitan area is disclosed The network is comprised of three basic types of nodes: an access multiplexer, a photonic switch, and a core node The access multiplexer provides multiplexing of data packets from end-users onto at least one sparse wavelength division multiplexed (SWDM) wavelength The SWDM wavelengths are carried over fiber cable to the photonic switches, which consolidate these wavelengths into dense wavelength division multiplexed (DWDM) wavelengths for transmission to the core node The core nodes include a photonic switch (PSX) and a service-aware terabit router core for routing packets within the metropolitan area via the network or out to a long haul network The photonic switches and core nodes are capable of switching at the wavelength, group of wavelength, and fiber levels

Packet loss in a bufferless optical WDM switch employing shared tunable wavelength converters

Abstract: We propose an architecture for a bufferless packet optical switch employing the wavelength dimension for contention resolution. The optical packet switch is equipped with tunable wavelength converters shared among the input lines. An analytical model Is proposed in order to determine the number of converters needed to satisfy prefixed packet loss probability constraints. This analytical model very accurately fits with simulations results. A sensitivity analysis of the required number of converters as a function of the main system parameters (number of input and output lines, number of wavelengths, ...) and traffic parameters has been carried out. Making use of the introduced dimensioning procedure we have observed that the proposed architecture allows a saving in terms of employed number of converters with respect to the other architectures proposed in literature. Such a saving can reach about 95% of the number of converters.

Flat-Gain L-Band Raman-EDFA Hybrid Optical Amplifier for Dense Wavelength Division Multiplexed System

Abstract: An efficient gain-flattened L-band optical amplifier is demonstrated using a hybrid configuration with a distributed Raman amplifier (DRA) and an erbium-doped fiber amplifier (EDFA) for 160 × 10-Gb/s dense wavelength division multiplexed system at 25-GHz interval. With an input signal power of 3 mW, a flat gain of >; 10 dB is obtained across the frequency range from 187 to 190.975 THz with a gain variation of ; 8.9 dBm) ever reported for a DRA-EDFA hybrid optical amplifier at reduced channel spacing.

Dependence of cross-phase modulation on channel number in fiber WDM systems

Abstract: The phase term appearing in the expression for cross-phase modulation due to the optical Kerr effect depends on the sum of the powers carried by each wavelength channel. For this reason, one might expect that the amount of cross-phase modulation would increase with increasing channel number, causing increased interference among channels and hence limiting the total number of channels that a WDM system can support. However, computer simulations of multichannel systems have shown no change in signal distortion as the number of wavelength channels is increased from four to eight. In a simulated three-channel system, the signal distortion of the central channel approaches that of a single-channel system as the wavelength separation is increased to approximately 2 nm. Thus, even a moderate amount of dispersion tends to cancel out the influence of cross-phase modulation, so that beyond a certain wavelength spacing, additional channels do not interfere with the channel under consideration. From these observations, we conclude that cross-phase modulation does not limit the number of wavelength channels that a single optical fiber can support. However, self- and cross-phase modulation are not the only nonlinear effects influencing fiber lightwave systems. Stimulated Raman scattering tends to transfer optical power from short-wavelength channels to channels operating at longer wavelength, degrading their signal-to-noise ratio. The efficiency of this process increases with increasing wavelength spacing. Clearly, a compromise needs to be reached between the conflicting requirements imposed by the optical Kerr effect and by stimulated Raman scattering. >

Lightwave Technology: Components and Devices

Abstract: Preface.1. Optical Fibers.2. Passive Fiber Components.3. Active Fiber Components.4. Planar Waveguides.5. Semiconductor Lasers and Amplifiers.6. Optical Modulators.7. Photodetectors.8. WDM Components.9. Optical Switching.10. Time-Domain Switching.Appendix A: System of Units.Appendix B: Software Package.Appendix C: Acronyms.Index.