Alcatel

Broadcom Corporation

Lambda-x Ophthalmics

Alcatel Lucent

Philippe Antoine

Miguel Peeters

Thierry Pollet

Luc Joannes

Luc Vandendorpe

Wim André Paula De Wilde

Geert Goris

Dimitri Marcel Saey

Francois Alain Roger Deryck

Pieter Geeraerts

Luc Boussemaere

A system for measuring () a sample () by deflectometry comprising:

Deflectometry measurement system

Provided is a method and system for increasing cyclic prefix and cyclic suffix based upon a fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT). The method includes representing at least one of the one or more DMT symbols in frequency domain to produce a frequency domain representation. The frequency domain representation corresponds to a quadrature amplitude modulation (QAM) constellation. Next the QAM constellation is rotated in the frequency domain by changing a characteristic of the DMT symbol as a function of tone index (k), cyclic extension length (CE), inverse fast fourier transform (IFFT) size (N), and pi. Finally, a number of extended symbols are produced to represent the DMT symbol based upon the rotating.

Method and system for a robust initialization symbol for digital duplexing

To generate a pseudo-random sequence of multi-carrier data symbols, a pseudo-random bit sequence is produced by repetitively generating a pseudo-random sequence of L bits, L being a first integer value. To create a multi-carrier data symbol, N bits are used, N being a second integer value. The pseudo-random bit sequence is subdivided into strings of N' bits, N&#x2032; being a third integer value larger than N, and N bits out of each string of N&#x2032; bits are used to generate a respective multi-carrier data symbol. N&#x2032;-N bits out of each string of N&#x2032; bits are left unused.

Method to generate a pseudo random sequence of multi carrier data symbols, and related transmitter and receiver

In a multi-carrier system, the carriers (f. . . f, f. . . f, . . . , f. . . f) are grouped in subsets (SUBSETSUBSET. . . ; SUBSET). A constellation information transmitting arrangement (BiGi_TA), for instance located in the multi-carrier receiver (RX), produces for each carrier subset (SUBSETSUBSET. . . ; SUBSET) a limited set of parameter values (BGBG. . . ; BG) and transmits these sets of parameter values (BGBG. . . ; BG) to a constellation information receiving arrangement (BiGi_RA), for instance located in the multi-carrier transmitter (TX). Through interpolation of the limited set of parameter values (BGBG. . . ; BG) the latter constellation information receiving arrangement (BiGi_RA) determines the constellation where each carrier (f. . . f, f. . . f, . . . , f. . . f) of a carrier subset (SUBSETSUBSET. . . ; SUBSET) will be modulated with.

Carrier constellation information in multi-carrier systems

The invention relates to a method to synchronise a multi-carrier transmission system wherein a time misalignment between a transmitter and a receiver is determined through an average of at least two pilot tones phase errors (&#xd8;) weighted in accordance with the noise affecting each pilot tone transmission. Such method is characterised in that, when the noise affecting a pilot tone () reaches a predetermined level, the pilot tone function is reallocated from this pilot tone () to another carrier () and/or this pilot tone weight is reduced.

Method and arrangement to synchronize a multi-carrier transmission system

To generate a pseudo-random sequence (PRMS) of multi-carrier data symbols (DMT, DMT, DMT), a pseudo-random bit sequence (PRBS) is produced by repetitively generating a pseudo-random sequence of L bits, L being a first integer value (L=4). To create a multi-carrier data symbol (DMT, DMT, DMT) N bits are used, N being a second integer value (N=8). The pseudo-random bit sequence (PRBS) is subdivided into strings of N' bits, N&#x2032; being a third integer value larger than N (N&#x2032;=9), and N bits out of each string of N&#x2032; bits are used to generate a respective multi-carrier data symbol (DMT, DMT, DMT). N&#x2032;-N bits out of each string of N&#x2032; bits are left unused.

Method to generate pseudo-random sequence of multi-carrier data symbols, and related transmitter and receiver

A multi-carrier receiver selects antennas (A, A), i.e. carriers whereto a small amount of power and data is allocated, for estimation of characteristics of a narrowband disturber (RFI-Signal-) in the Radio Frequency Interference band (RFI-Band), a predetermined band for e.g. radio amateur transmission. These antennas (A, A) can be selected amongst all carriers located inside the Radio Frequency Interference band (RFI-Band) and at least two carriers (C, C) located outside the Radio Frequency Interference band (RFI-Band).

Multi-carrier receiver with improved radio frequency interference canceling

The invention relates to a modem and a method for providing bit loading computation in a multi-carrier communication system, using a plurality of simultaneous different carriers or tones by measuring the signal to noise ratios (SNRs) for carriers and by determining in dependence of the SNR a related number of bits to be allocated to the respective carrier. The method comprises the steps of providing a sliding window having a frequency width able to contain a predetermined number of the carriers, moving the sliding window over the frequency spectrum of the carriers through a plurality of positions of the window with respect to the carrier frequencies, and when the window contains the predetermined number of the carriers and there is at least one further carrier to be positioned in the window as a new carrier for bit allocation, the window is moved such that on entering a new carrier into the window at one of its borders, a carrier already in the window at the other frequency border leaves the window. For each position of the window determining bit allocation for the respective at least one carrier, and in the event that a predetermined average power spectrum density threshold (TPSD) of the carriers over the window for the present window position is not respected, selecting at least one carrier within the window for power spectrum density reduction.

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Walhain, Belgium

Philippe Antoine