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.

Cellular telephone as an authenticated transaction controller

Abstract: The invention includes arrangements for providing credit to customers via cellular telephones. In one embodiment, a customer seeking credit for the purchase of goods and services from a merchant (at 30) activates his or her cellular telephone (10), authenticates the cellular telephone with his cellular service provider's base station (20), and proceeds to establish a connection (to 40) to obtain credit. Credit is obtained by sending a unique sequence to the cellular service provider that is different from the normal sequence of numbers that correspond to a telephone number of the called party. That sequence may include a merchant ID code and the amount of credit desired.

A better understanding and an improved solution to the specific problems of stereophonic acoustic echo cancellation

Abstract: Teleconferencing systems employ acoustic echo cancelers to reduce echoes that result from coupling between the loudspeaker and microphone. To enhance the sound realism, two-channel audio is necessary. However, in this case (stereophonic sound) the acoustic echo cancellation problem is more difficult to solve because of the necessity to uniquely identify two acoustic paths. We explain these problems in detail and give an interesting solution which is much better than previously known solutions. The basic idea is to introduce a small nonlinearity into each channel that has the effect of reducing the interchannel coherence while not being noticeable for speech due to self masking.

Scanning Single-Electron Transistor Microscopy: Imaging Individual Charges

Abstract: A single-electron transistor scanning electrometer (SETSE)—a scanned probe microscope capable of mapping static electric fields and charges with 100-nanometer spatial resolution and a charge sensitivity of a small fraction of an electron—has been developed. The active sensing element of the SETSE, a single-electron transistor fabricated at the end of a sharp glass tip, is scanned in close proximity across the sample surface. Images of the surface electric fields of a GaAs/AlxGa1−xAs heterostructure sample show individual photo-ionized charge sites and fluctuations in the dopant and surface-charge distribution on a length scale of 100 nanometers. The SETSE has been used to image and measure depleted regions, local capacitance, band bending, and contact potentials at submicrometer length scales on the surface of this semiconductor sample.

FPGA-based processor

Abstract: A multiprocessor having an input/output controller, a process controller, and a multidimensional arrays of field programmable gate arrays (FPGAs), each FPGA having its own local memory. The multiprocessor may be programmed to function as a single-instruction, multiple-data (SIMD) parallel processor having a matrix of processing elements (PEs), where each FPGA may be programmed to operate as a submatrix array of PEs. The multiprocessor is especially useful for image processing, pattern recognition, and neural network applications.

Reply to Simon's Comment on "Evidence for an Anisotropic State of Two-Dimensional Electrons in High Landau Levels"

Abstract: We recently reported [PRL 82, 394 (1999)] large transport anisotropies in a two-dimensional electron gas in high Landau levels. These observations were made utilizing both square and Hall bar sample geometries. Simon recently commented [cond-mat/9903086] that a classical calculation of the current flow in the sample shows a magnification of an underlying anisotropy when using a square sample. In this reply we present more recent data obtained with a very high mobility sample, and reiterate that, with or without magnification, an anisotropic state develops in high Landau levels at very low temperatures.