Abstract: An audio signal encoded in the form of data is spectrally reconstructed so part of the frequency spectrum of the audio signal is decoded with a spectral band limiting encoder (i.e., a core encoder). The complementary part of the frequency spectrum of the audio signal is decoded with an extension encoder. Information representing at least one cut-off frequency of the signal decoded by the core decoder is used to select, from amongst the data to be decoded or the data decoded with the extension decoder.

Abstract: A method for restoring a partial between a peak Pi and a peak Pi+N whose frequency and phase are known. The method (1) comprises the steps of estimating (2) the frequency {circumflex over (?)} of each of the missing peaks Pi+1 to Pi+N?1 of this partial, calculating (3) the phase {circumflex over (?)} from peak to peak, from the phase of the peak Pi to that of the peak Pi+N, for all the frequencies {circumflex over (?)} previously estimated, calculating (4) the phase error err? between the calculated phase {circumflex over (?)} and the known phase at the same peak Pi+N, and correcting (5) each calculated phase {circumflex over (?)} by a value that is a function of the phase error err?.

Abstract: An audio signal encoded in the form of data is spectrally reconstructed so part of the frequency spectrum of the audio signal is decoded with a spectral band limiting encoder (i.e., a core encoder). The complementary part of the frequency spectrum of the audio signal is decoded with an extension encoder. Information representing at least one cut-off frequency of the signal decoded by the core decoder is used to select, from amongst the data to be decoded or the data decoded with the extension decoder.

Abstract: The present invention relates to a method of binary encoding the N points of a constellation corresponding to the discrete positions, in amplitude and in phase, associated with the encoding of binary words in the case of a multicarrier modulation of OFDM type (Orthogonal Frequency Division Multiplexing) of a digitized signal. According to the method, two adjacent points of the constellation correspond to binary words which differ from one another by at most two bits. The present invention applies in particular to digital television.

Abstract: The present invention relates to a method of realigning the local oscillators of a receiver, as well as a device for implementing the method. In a receiver with a high frequency/intermediate frequency translation oscillator, an intermediate frequency/baseband translation oscillator, and a sampling oscillator receiving a signal modulated by at least one circuit for inverse fast Fourier transform FFT.sup.-1 computation according to a multicarrier modulation of OFDM (Orthogonal Frequency Division Multiplexing) type with addition of a transition interval at the start of each transmission interval. The spectrum of the signal has two master lines with a fixed frequency difference between them.