Lucent Technologies Inc.

Alcatel Lucent

Alcatel-lucent USA Inc.

David J Thomson

Gregory Peter Kochanski

Partha Pratim Mitra

Michael R Andrews

Louis J Lanzerotti

George Endicott Rittenhouse

Karin Sigloch

Tin Kam Ho

Igal M Brener

Daniel D Lee

Dan L Philen

This inventions provides techniques for estimating both temporal and spectral channel fluctuations with the duration of a data symbol. Certain pulse shaping functions are Discrete Prolate Spheroidal Sequences (DPSSs) and are used primarily because of their relatively limited Inter-Symbol Interference (ISI) properties. During reception, these properties allow one or more parameters of a joint time-frequency channel model to be more easily determined. Once the one or more parameters are determined, they can be applied to received symbols to correct the temporal fluctuations, spectral fluctuations, or both of the channel over which a communication took place. The techniques may be adapted for the Multiple-In, Multiple-Out communication situation.

Communicating over single- or multiple- antenna channels having both temporal and spectral fluctuations

Techniques for communicating over single-or multiple-antenna channels having both temporal and spectral fluctuations

Techniques for reducing or eliminating effects of noise on a wireless communication system are provided. In one aspect of the invention, the technique comprises monitoring noise attributable to an interference source that may affect one or more components of the wireless communication system. The interference source being monitored is distant from the wireless communication system to the degree that noise arrives at the wireless communication system within a substantially point source-like angular range. For example, the noise may be attributable to the sun or tropospheric ducting. The technique then comprises initiating one or more operations, as a function of the monitored noise, to reduce or eliminate the effects of the noise attributable to the distant interference source at one or more of the components of the wireless communication system that are determined to be affected by such noise.

Methods and apparatus for mitigating the effects of solar noise and the like on a wireless communication system

A method and apparatus are disclosed for equalizing a channel using improved channel estimates. The present invention assumes that fading will follow a statistical model and obtains an improved channel estimate using one or more basis functions to describe the channel based on known channel statistics. A Karhunen-Loeve expansion can be used for channel estimation to describe the channel. Waveforms are selected that are matched to characteristics of the channel, such as transmission waveforms whose energy is largely restricted to a bandwidth assigned to the channel. Coefficients are estimated for the basis functions using real-time data.

Method and apparatus for estimating a channel based on channel statistics

Systems and techniques for location determination. A plurality of tags emitting radio frequency signals are dispersed throughout a region, such as a building, within which a user's location is to be determined. The radio frequency signals emitted by the tags include information that can be used to identify the location in which the tags axe placed, or simply to distinguish the tags from one another. A portable device receives signals from the tags and provides the signal information to a location server that computes the location of the portable device by comparing the signal information received from the portable device to a map of location venus stored signal information, and identifies the location of the portable device as the location for which the stored signal information best matches the signal information received from the portable device.

Methods and apparatus for location determination based on dispersed radio frequency tags

An accurate and simplified method of non-destructively measuring the zero-dispersion wavelength along the length of a single-mode fiber is disclosed. The method includes the steps of measuring the FWM intensity of the optical fiber at a plurality of wavelengths, plotting the measured FWM intensity at each of the plurality of wavelengths to obtain a curve representative of the FWM intensity of each of the plurality of wavelength, and performing a non-linear inversion on the curve to obtain the zero-dispersion wavelength along the length of the fiber.

High-resolution zero-dispersion wavelength mapping in single mode fiber

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Kingston, Canada

David J Thomson