Alcatel-Lucent

About: Alcatel-Lucent is a based out in Stuttgart, Germany. It is known for research contribution in the topics: Signal & Network packet. The organization has 37003 authors who have published 53332 publications receiving 1430547 citations. The organization is also known as: Alcatel-Lucent S.A. & Alcatel.

Optical all-pass filters for phase response design with applications for dispersion compensation

Abstract: Lossless all-pass optical filters are introduced, which can approximate any desired phase response while maintaining a constant, unity amplitude response. Architectures using cascade and lattice structures based on ring resonators and cavities defined by reflectors are discussed. Two applications are presented: 1) for fiber dispersion compensation and 2) for compensation of the nonlinear phase response of narrow bandpass optical filters such as thin-film or Bragg grating filters. All orders of dispersion can be compensated in principle, and the filters are periodic so multiple channels can be compensated with a single device. The architectures are very compact compared to alternatives such as chirped Bragg gratings.

Pseudogap phase and the quantum-critical point in copper-oxide metals

Abstract: A systematic solution of a model for copper oxides reveals a line of transitions ${T\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}T}_{p}(x)$ for $x$, the doping away from half filling less than a critical value, to a phase with broken time reversal and rotational symmetry. The single-particle spectrum in this phase is calculated to have a gap $\ensuremath{\sim}[\mathrm{cos}({k}_{x}a/\ensuremath{\pi})\ensuremath{-}\mathrm{cos}({k}_{y}a/\ensuremath{\pi}){]}^{2}$. The properties in this phase are compared to the properties of the so-called ``pseudogap phase'' of the copper oxides.

Client-side parallel requests for network services using group name association

Abstract: A registration applet embedded in a registration page of a browser program allows a user to associate a user-specified group name with a plurality of UTRLs, HTTP POST or GET requests or other network service identifiers, such that the group name designates a category of information provided by corresponding network services. An access applet embedded in an access page of the browser allows a user to select one of several previously-registered group names, and an access mode for processing responses to service requests. A processor running the access applet automatically issues parallel requests to the network services associated with a selected group name in response to entry of a command by the user. The user may select a parallel-any access mode, in which the processor displays only the first response to the parallel requests, a parallel-all mode, in which the processor directs the display of multiple responses in a user-specified display format, or a retry access mode, in which the processor reissues a network service request if a response to a previous request is not received within a predetermined time period.

Intra-channel cross-phase modulation and four-wave mixing in high-speed TDM systems

Abstract: A comprehensive numerical and experimental study of 40 Gbit/s RZ transmission is presented which reveals two new forms of nonlinear interactions that limit the speed of high-speed systems. Both limitations originate from nonlinear interactions among neighbouring bits. The first interaction involves cross-phase modulation and leads to timing fluctuations while the second interaction originates from four-wave mixing and leads to the creation of shadow pulses.

Distributed architecture for real-time flow measurement at the network domain level

Abstract: A virtual router network (VRN) for performing real-time flow measurements (RTFM) is provided. The VRN effectively reduces the number of traffic metering points required thereby simplifying the aggregation and exportation of flow records to a collector. The collector may be service manager in a network management system. The metering points, in a preferred embodiment, are at virtual interfaces (VI) which are edge nodes in VRN. One of the virtual interfaces is selected as a master virtual interface and act as a collector and distributor of flow related information. In one aspect of the invention the VRN is used to provide, non-invasively, per-flow delay monitoring in a communication system.