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.

Broad-band erbium-doped fiber amplifier flattened beyond 40 nm using long-period grating filter

Abstract: Broad-bandwidth amplification is essential for the construction of high-capacity multichannel communication systems. We describe a silica-based erbium doped fiber amplifier (EDFA) with a flat gain bandwidth exceeding 40 nm. The dual-stage EDFA includes a precisely designed inter-stage long-period fiber grating filter with more than 14-dB peak attenuation. By careful choice of the filter spectrum and fiber lengths, this EDFA is flat to within 1 dB over 40 nm while producing a noise figure below 4.0 dB and nearly +15-dBm output power.

SUCCESS: a next-generation hybrid WDM/TDM optical access network architecture

Abstract: In this paper, the authors propose a next-generation hybrid WDM/TDM optical access network architecture called Stanford University aCCESS or SUCCESS. This architecture provides practical migration steps from current-generation time-division multiplexing (TDM)-passive optical network (PONs) to future WDM optical access networks. The architecture is backward compatible for users on existing TDM-PONs, while simultaneously capable of providing upgraded high-bandwidth services to new users on DWDM-PONs through advanced WDM techniques. The SUCCESS architecture is based on a collector ring and several distribution stars connecting the CO and the users. A semipassive configuration of the Remote Nodes (RNs) enables protection and restoration, making the network resilient to power failures. A novel design of the OLT and DWDM-PON ONUs minimizes the system cost considerably: 1) tunable lasers and receivers at the OLT are shared by all ONUs on the network to reduce the transceiver count and 2) the fast tunable lasers not only generate downstream data traffic but also provide DWDM-PON ONUs with optical CW bursts for their upstream data transmission. Results from an experimental system testbed support the feasibility of the proposed SUCCESS architecture. Also, simulation results of the first SUCCESS DWDM-PON MAC protocol verify that it can efficiently provide bidirectional transmission between the OLT and ONUs over multiple wavelengths with a small number of tunable transmitters and receivers.

Power consumption modeling in optical multilayer networks

Abstract: The evaluation of and reduction in energy consumption of backbone telecommunication networks has been a popular subject of academic research for the last decade. A critical parameter in these studies is the power consumption of the individual network devices. It appears that across different studies, a wide range of power values for similar equipment is used. This is a result of the scattered and limited availability of power values for optical multilayer network equipment. We propose reference power consumption values for Internet protocol/multiprotocol label switching, Ethernet, optical transport networking and wavelength division multiplexing equipment. In addition we present a simplified analytical power consumption model that can be used for large networks where simulation is computationally expensive or unfeasible. For illustration and evaluation purpose, we apply both calculation approaches to a case study, which includes an optical bypass scenario. Our results show that the analytical model approximates the simulation result to over 90% or higher and that optical bypass potentially can save up to 50% of power over a non-bypass scenario.

Multiwavelength data communication fiber link

Abstract: An optical multi-channel data communication link transmits data from a transmitter to a remote receiver. The link includes a multimode laser diode source connected to the transmitter, a device for modulating the source with each channel of data to generate a modulated light wave, and a wavelength division multiplexing device at the transmitter. The wavelength division multiplexing device has paraxial optics for multiplexing the light waves to produce a multiplexed signal. Multimode fiber optic means are connected to the multiplexer and pass the multiplexed signal to the remote receiver. A wavelength division multiplexer has paraxial optics for demultiplexing the multiplexed signals at the receiver to produce demultiplexed light waves. Each of the demultiplexed light waves are converted for use by the receiver. Preferably, each of the wavelength division multiplexer and demultiplexer has a littrow reflecting grating and a lens which are paraxially aligned with the multimode fiber optic means to provide channel separation of less than 50 nm.

Integrated frequency comb source of heralded single photons

Abstract: We report an integrated photon pair source based on a CMOS-compatible microring resonator that generates multiple, simultaneous, and independent photon pairs at different wavelengths in a frequency comb compatible with fiber communication wavelength division multiplexing channels (200 GHz channel separation) and with a linewidth that is compatible with quantum memories (110 MHz). It operates in a self-locked pump configuration, avoiding the need for active stabilization, making it extremely robust even at very low power levels.