Other

France Telecom

Telediffusion De France

France Telecom, Telediffusion De France

Wavecom

Pierre Combelles

Damien Castelain

Jean-Francois Helard

Michel Alard

Bertrand Sueur

Ali M Jalali

Dominique Lacroix

Dominique Lacroix-Penther

Denis Callonnec

Dominique M LaCroix

A multicarrier signal, which includes a temporal succession of symbols formed by a set of data elements, each of said data elements modulating a carrier frequency of the signal. The data elements include reference elements called pilots, whereof the value in transmission is known to at least one receiver designed to receive the signal and informative data elements, whereof the value in transmission is not known a priori to the at least one receiver. One of the caffier frequencies is modulated, at a given time, by one of the data elements, being called a carrier. At least one constraint is imposed on the value of at least one of the informative data elements, so as to reduce, in reception, at least one term of interference affecting at least one of the pilots.

Distributed pilot multicarrier signal designed to limit interference affecting said pilots

A method of modulating a multicarrier signal involves obtaining a set of 2M representative complex coefficients of transmitted data. 2LM linear combinations are calculated so as to leave 2M obtained complex coefficients. Coefficients of balancing used in these combinations represent a prototype function g(t). The 2LM coefficients are summed in given areas of memory. The 2LM memory sites represent 2L groups of M distinct partial sums. The transmitted samples are sent so as to gradually form M samples to transmit, in the memory sites, over a defined duration.

Multicarrier modulation using weighted prototype functions

A method for estimating an interference phase shift when receiving a multicarrier signal formed of a time series of symbols modulating a plurality of carrier frequencies, at least some of the carrier frequencies of at least some of the symbols bearing reference elements, whereof the value at transmission level is known by the receiver carrying out the reception. The phase variation &dgr; between at least two symbols bearing reference elements is estimated by analysing the reference elements. Each of the reference elements in the estimation is weighted by information representing the noise affecting the carrier frequency bearing the reference element.

Process for estimating a parasite phase shift during reception of a multi-carrier signal and the corresponding receiver

A method for the time synchronization of a multi-carrier signal receiver consisting of a sequence of symbols each formed by a plurality of carrier frequencies. Each carrier frequency is modulated by a modulation coefficient. The position of some of said carrier frequencies in the time-frequency space is known to the receiver, and said frequencies are reference carrier frequencies. Each reference carrier frequency bears a reference coefficient with a value that is known to the receiver. The method includes a fine synchronization step, wherein the signal transmission channel impulse response is estimated on the basis of reference coefficients belonging to at least two received symbols. The beginning of the useful portion of each of the symbols is determined, and/or a receiver clock is controlled by analyzing the estimate of said impulse response.

Multi-carrier symbol synchronization

To interleave or deinterleave data elements in first and second blocks transmitted alternately and each having N data elements with rank n lying between 0 and N&minus;1, N being an integer, the data elements with ranks 0, . . . n, . . . N&minus;1 in the first blocks are ordered in accordance with the successive ranks A(0), . . . A(n), . . . A(N&minus;1) and the data elements with ranks 0, . . . n, . . . N&minus;1 in the second block are ordered in accordance with the successive ranks A,(0), . . . A,(n), . . . A,(N&minus;1). A and A,are different functions such that A,(A(n))&equals;n.

Data element interleaving/deinterleaving

Growing community of inventors

Rennes, France

Pierre Combelles