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.

A heuristic wavelength assignment algorithm for multihop WDM networks with wavelength routing and wavelength re-use

Abstract: Presents a heuristic algorithm for effectively assigning a limited number of wavelengths among the access stations of a multihop network wherein the physical medium consists of optical fiber segments which interconnect wavelength-selective optical switches. Such a physical medium permits the limited number of wavelengths to be re-used among the various fiber links, thereby offering very high aggregate capacity. Although the optical connectivity among the access station can be altered by changing the states of the various optical switches, the resulting optical connectivity pattern is constrained by the limitation imposed at the physical level. The authors also study two routing schemes, used to route requests for virtual connections. The heuristic is tested on a realistic traffic model, and the call blocking performance of new requests for virtual connections is studied through extensive simulations and compared against the blocking performance of an ideal infinite capacity centralized switch (lowest possible call blocking caused exclusively by congestion on the finite capacity user input/output links, never by the switch fabric itself). Surprisingly, the authors find that, for a wide range of parameters, the blocking performance of the lightwave network is almost the same as that of the ideal centralized switch. From these results, they conclude that the heuristic algorithm is effective and the routing scheme is efficient. >

Multiwavelength optical networks with limited wavelength conversion

Abstract: This paper proposes optical wavelength division multiplexed (WDM) networks with limited wavelength conversion that can efficiently support lightpaths (connections) between nodes. Each lightpath follows a route in a network and must be assigned a channel on each link along the route. The load /spl lambda//sub max/ of a set of lightpaths is the maximum over all links of the number of lightpaths that use the link. At least /spl lambda//sub max/ wavelengths will be needed to assign channels to the lightpaths. If the network has full wavelength conversion capabilities, then /spl lambda//sub max/ wavelengths are sufficient to perform the channel assignment. Ring networks with fixed wavelength conversion capability within the nodes are proposed that can support all lightpath sets with load /spl lambda//sub max/ at most W-1, where W is the number of wavelengths in each link. Ring networks with a small additional amount of wavelength conversion capability within the nodes are also proposed that allow the support of any set of lightpaths with load /spl lambda//sub max/ at most W. A star network is also proposed with fixed wavelength conversion capability at its hub node that can support all lightpath sets with load /spl lambda//sub max/ at most W. These results are extended to tree networks and networks with arbitrary topologies. This provides evidence that significant improvements in traffic-carrying capacity can be obtained in WDM networks by providing very limited wavelength conversion capability within the network.

Highly nonlinear dispersion-flattened photonic crystal fibers for supercontinuum generation in a telecommunication window.

Abstract: We propose a new structure of highly nonlinear dispersion-flattened (HNDF) photonic crystal fiber (PCF) with nonlinear coefficient as large as 30 W(-1)km(-1) at 1.55 microm designed by varying the diameters of the air-hole rings along the fiber radius. This innovative HNDF-PCF has a unique effective-index profile that can offer not only a large nonlinear coefficient but also flat dispersion slope and low leakage losses. It is shown through numerical results that the novel microstructured optical fiber with small normal group-velocity dispersion and nearly zero dispersion slope offers the possibility of efficient supercontinuum generation in the telecommunication window using a few ps pulses.

Polarization-independent all-fiber wavelength-division multiplexer based on a Sagnac interferometer.

Abstract: An all-fiber wavelength-division multiplexer (WDM) based on the nonreciprocity of the birefringence to the polarization states is proposed. The transfer function of a Sagnac interferometer is wavelength dependent if the loop birefringence of the interferometer consists of both circular and linear parts. Theoretical analysis shows that the output characteristics of this WDM are similar to those of a fiber taper-based device. Both the bandwidth and the peak wavelength of the new WDM can be tuned by changing the loop birefringence. Experimental prototypes exhibit a channel isolation greater than 25 dB with peak passband insertion loss of less than 1 dB.

19-core fiber transmission of 19×100×172-Gb/s SDM-WDM-PDM-QPSK signals at 305Tb/s

Abstract: A novel free-space coupling system combined with a multi-core fiber enables up-scaling to a record space-division-multiplexed (SDM) channel number of 19. We achieve 305-Tb/s transmission over 10.1 km using 19-SDM, 100-WDM PDM-QPSK signals.