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.

Method and apparatus for mirroring traffic over a network

Abstract: A method and apparatus for mirroring traffic from a first network device to a second network device are disclosed. The method includes the selecting of one or more ingress frames from an ingress stream using mirror classification criteria; duplicating the one or more ingress frames; appending a mirrored flow encapsulation header with a virtual local area network tag; transmitting the duplicate frames with tags from the first network device to the second network device; and removing the mirrored flow encapsulation header at the target network device to regenerate the ingress frames originally received at the first network device. The ingress frames may then be forwarded to an egress port of the second network device and analyzed by a traffic analysis tool, for example. With the invention, the traffic received at the first network device may be analyzed remotely.

Quantum Computing with Electrons Floating on Liquid Helium

Abstract: A quasi–two-dimensional set of electrons (1

Ultra-broadband semiconductor laser.

Abstract: The fundamental mechanism behind laser action leads in general only to narrowband, single-wavelength emission. Several approaches for achieving spectrally broadband laser action have been put forward, such as enhancing the optical feedback in the wings of the gain spectrum, multi-peaked gain spectra, and the most favoured technique at present, ultrashort pulse excitation. Each of these approaches has drawbacks, such as a complex external laser cavity configuration, a non-flat optical gain envelope function, or an inability to operate in continuous mode, respectively. Here we present a monolithic, mid-infrared 'supercontinuum' semiconductor laser that has none of these drawbacks. We adopt a quantum cascade configuration, where a number of dissimilar intersubband optical transitions are made to cooperate in order to provide broadband optical gain from 5 to 8 microm wavelength. Laser action with a Fabry-Perot spectrum covering all wavelengths from 6 to 8 microm simultaneously is demonstrated with this approach. Lasers that emit light over such an extremely wide wavelength range are of interest for applications as varied as terabit optical data communications or ultra-precision metrology and spectroscopy.

CS-ACELP speech compression system with adaptive pitch prediction filter gain based on a measure of periodicity

Abstract: A speech coding system employing an adaptive codebook model of periodicity is augmented with a pitch-predictive filter (PPF). This PPF has a delay equal to the integer component of the pitch-period and a gain which is adaptive based on a measure of periodicity of the speech signal. In accordance with an embodiment of the present invention, speech processing systems which include a first portion comprising an adaptive codebook and corresponding adaptive codebook amplifier and a second portion comprising a fixed codebook coupled to a pitch filter, are adapted to delay the adaptive codebook gain; determine the pitch filter gain based on the delayed adaptive codebook gain, and amplify samples of a signal in the pitch filter based on said determined pitch filter gain. The adaptive codebook gain is delayed for one subframe. The pitch filter gain equals the delayed. adaptive codebook gain, except when the adaptive codebook gain is either less than 0.2 or greater than 0.8., in which cases the pitch filter gain is set equal to 0.2 or 0.8, respectively.

Improved quasi-orthogonal codes through constellation rotation

Abstract: Orthogonal codes are a class of space-time block codes that achieve full diversity gain, though typically at a loss of code rate. Such codes have simple single-symbol decoders. The code rate can be made higher by constructing quasi-orthogonal codes (such as those proposed last year in [1], [2]) which trade a small loss of performance for full rate coding. In this paper, which builds on previous work in [1], we propose a novel rotation technique for improving the performance of quasi-orthogonal codes in terms of bit-error rate (BER). Numerical simulations show that significant improvements to previously reported results without rotation can be attained.