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.

A steerable and variable first-order differential microphone array

Abstract: A new first-order differential microphone array with an infinitely steerable and variable beampattern is described. The microphone consists of 6 small pressure microphones flush-mounted on the surface of a 3/4" diameter rigid nylon sphere. The microphones are located on the surface at points where included octahedron vertices contact the spherical surface. By appropriately combining the three Cartesian orthogonal pairs with simple scalar weightings, a general first-order differential microphone beam (or beams) can be realized and directed to any angle in 4/spl pi/ steradian space. A working real-time version has been created and measured results from this microphone are shown. This microphone should be useful for surround sound recording/playback applications and to virtual reality audio applications.

Understanding Dynamic Spectrum Access: Models,Taxonomy and Challenges

Abstract: In last few years, especially after release of the FCC Spectrum Policy Task Force (SPTF)'s seminal report in 2002, we have witnessed growing interest in the field of Dynamic Spectrum Access (DSA) networks. Terms such as reconfigurable networks, Software Defined Radios (SDRs), Cognitive Radios and Cognitive Radio Networks (CRNs) have gained common use. Radio spectrum is a multidimensional entity; space, time, polarization, frequency, power of signal transmission and interference are some of the key dimensions. The static, command- and-control management of spectrum has led to barriers to accessing the spectrum in various dimensions. The notion of dynamic spectrum access can break these barriers in one or more of the dimensions. A review of published research in the technology, policy and legal facets of this broad area indicates that the community is addressing this problem from multitude of angles. In fact, we believe the situation is analogous to story of seven blind men attempting to describe an elephant based on what they perceive when they touch various parts of the elephant. As such, we contend that unless a clear taxonomy of various ways of dynamic access is developed, significant confusion can prevail within the community dealing with these new ways. This paper tries to rectify this situation. It aims to develop a clear taxonomy of various forms of DSA networks, describe in detail various models and identify required technology capabilities, architectural innovations and policy changes.

Scheduling tests for VLSI systems under power constraints

Abstract: This paper considers the problem of testing VLSI integrated circuits in minimum time without exceeding their power ratings during test. We use a resource graph formulation for the test problem. The solution requires finding a power-constrained schedule of tests. Two formulations of this problem are given as follows: (1) scheduling equal length tests with power constraints and (2) scheduling unequal length tests with power constraints. Optimum solutions are obtained for both formulations. Algorithms consist of four basic steps. First, a test compatibility graph is constructed from the resource graph. Second, the test compatibility graph is used to identify a complete set of time compatible tests with power dissipation information associated with each test. Third, from the set of compatible tests, lists of power compatible tests are extracted. Finally, a minimum cover table approach is used to find an optimum schedule of power compatible tests.

Ultrahigh-resolution optical coherence tomography by broadband continuum generation from a photonic crystal fiber

Abstract: We have developed an ultrahigh-resolution optical coherence tomographic system in which broadband continuum generation from a photonic crystal fiber is used to produce high longitudinal resolution. Longitudinal resolution of 1.3-microm has been achieved in a biological tissue by use of continuum light from 800 to 1400 nm. The system employed a dynamic-focusing tracking method to maintain high lateral resolution over a large imaging depth. Subcellular imaging is demonstrated.

Point of sale method and system

Abstract: A method for providing point-of-sale (POS) payment using interactive television (ITV) or the world wide web (WWW) by directly debiting a customer's bank account through electronic transfer of funds or by billing a customer's credit card account. The customer places an order for products or services on his ITV station, or through the WWW from his personal computer, and can make POS payment either by authorizing direct debit from his bank account or by authorizing a charge to his credit card account. The customer's debit and credit account information is collected by swiping the customer's debit or credit card through a magnetic stripe reader at the customer's location at the moment of sale.