Abstract: The invention concerns a method for spectral enhancement and a device therefor. The inventive method is a method for enhancing spectral content of a signal having an incomplete spectrum including a first spectral band, the method including the following steps: at least transposing the spectral content of the first band into a second spectral band not included in the spectrum to generate a transposed spectrum signal, with spectrum limited to the second spectral band; transforming the spectrum of the transposed spectrum signal to obtain an enhancing signal; combining the incomplete spectrum signal and the enhancing signal to produce a spectrum enhanced signal. The invention is characterized in that the spectral content is subjected to a whitening step.

Abstract: The invention concerns a method for spectral enhancement and a device therefor. The inventive method is a method for enhancing spectral content of a signal having an incomplete spectrum including a first spectral band, the method including the following steps: at least transposing the spectral content of the first band into a second spectral band not included in the spectrum to generate a transposed spectrum signal, with spectrum limited to the second spectral band; transforming the spectrum of the transposed spectrum signal to obtain an enhancing signal; combining the incomplete spectrum signal and the enhancing signal to produce a spectrum enhanced signal. The invention is characterised in that the spectral content is subjected to a whitening step.

Abstract: To avoid searching for a new location for very high hectometric wave antennas, an antenna according to the invention comprises an existing vertical structure having a height of at least approximately ten meters and including at least one electrically conductive element connected to the ground, and an excitation conductor wire (4a) that is essentially electrically conductive, disposed at least in part in the vicinity of and outside the structure and connected to a emitter (E) so that the structure radiates substantially hectometric waves. The existing structure may be a broadcasting tower, a water tower, a chimney, a lighthouse or a lamp standard, wherein the excitation wire merges visually. The wire can be replaced by a conductive loop a few meters long, magnetically coupled to the structure.

Abstract: A method for processing radio signals of a plurality of radio communication standards occupying a broadband frequency having a step which consists in broadband analysis to acquire information on the signals contained in the frequency broadband and selecting an appropriate narrowband processing to demodulate the radio signals; and a step which consists in processing in narrowband the radio signals contained in the frequency broadband to demodulate them.

Abstract: To avoid searching for a new location for very high hectometric wave antennas, an antenna according to the invention comprises an existing vertical structure having a height of at least approximately ten meters and including at least one electrically conductive element connected to the ground, and an excitation conductor wire (4a) that is essentially electrically conductive, disposed at least in part in the vicinity of and outside the structure and connected to a emitter (E) so that the structure radiates substantially hectometric waves. The existing structure may be a broadcasting tower, a water tower, a chimney, a lighthouse or a lamp standard, wherein the excitation wire merges visually. The wire can be replaced by a conductive loop a few meters long, magnetically coupled to the structure.

Abstract: The invention relates to a method for estimating the motion between two digital images and to the use of this method for coding images. The aim of the method is to eliminate the disturbances caused by the mesh being overturned during the motion estimation process. According to the invention, the method consists of carrying out a first motion estimation in order to identify the faulty mesh, i.e. the mesh that is overturning or is overlapping after the displacement vectors have been applied; then carrying out a second motion estimation, excluding at least said faulty mesh, in order to minimize prediction error on the remaining mesh of the model.

Abstract: A method of calculating the fast Fourier transform or the inverse fast Fourier transform of a series of N real samples x(n), with N power of two, operating according to a time interleaving algorithm and providing the sample series X(n) in ascending order to index n and using limited calculating storage means. A method of calculating the fast Fourier transform or the inverse fast Fourier transform of a series of N conjugated complex samples X(n), with N power of two, operating according to a frequency interleaving algorithm.

Abstract: The video component(s) of a digital audio-visual first program are switched onto the video components of a second digital, audio-visual program by (1) switching onto the video component of the second program, subsequent to the switch command and to the end of a picture of the first program, and (2) replacing, as seen in the order of transmission, each non Intra picture of the component of a second program, with a picture having coding performed independently of (a) the picture data of the replaced picture and (b) of the contents of the pictures to which it refers until the beginning of the next Intra picture of the component of the second program.

Abstract: First digital audio-visual program video component(s) are switched on a second digital audio-visual program video component(s) by switching on the beginning of the first set of images including an Intra-coded picture of the second program video component encountered after the switching command. In the transmission order of images, each bidirectionally predictive-coded picture of the first set of images referring to the set of images pertaining to the set of images preceding it before switching, is substituted for a bidirectionally predictive-coded picture of the video coding which is produced independently of (1) the substituted image content and (2) the contents of the images to which it refers.

Abstract: A method for encoding a digital image for producing a bit stream representing the image, the bit stream length depending on the quality of the desired representation, consisting in: a) defining, on the domain of the image to be encoded, a hierarchical meshing comprising a plurality of nested meshes whereof the mesh peaks are the image pixels; b) determining for each mesh of the hierarchical meshing, a brightness variation between the image to be encoded and an interpolated image obtained from the nested meshing peaks whereto pertains the mesh concerned; and c) inserting in the bit stream position, brightness and chrominance values of the peaks of meshes whereof the brightness variation is higher than a threshold variation useful for encoding fixed or animated images with speed reduction.

Abstract: A device for the reception of digital data broadcast at a high bit rate for reception by mobile receivers is disclosed. The device operates under adverse conditions of multiple propagation corresponding to the Rayleigh process and imperfect frequency tuning to minimize the inter-symbol interference in the frequency domain. The device receives a digital signal having digital elements distributed in the frequency-time space f-t and transmitted in the form of symbols each constituted by a multiplex of N orthogonal carrier frequencies modulated by a set of digital elements and broadcast simultaneously. The device includes a module for transposition by a local oscillator, baseband filtering and analog-digital conversion, a temporal windowing module for the selection of the useful samples and a mathematical transformation module, the temporal windowing module applying a Nyquist window type of temporal window with non-zero roll-off.

Abstract: A method for the broadcasting of digital data, intended to be received notably by mobile receivers moving about in an urban environment, that is, under conditions of multiple propagation and in the presence of parasites and jamming, enabling a coherent demodulation under such conditions of reception. This method is one for the broadcasting of digital data, notably for radio broadcasting at a high bit rate towards mobile receivers, of the type providing for the distribution of the data in the form of digital elements in the frequency-time space f-t and the transmission of symbols each constituted by a multiplex of N orthogonal carrier frequencies modulated by a set of digital elements and broadcast simultaneously, certain of the digital elements being reference elements with a value and position in the frequency-time space f-t that are known to the receivers.