Abstract: The invention relates to a method for the COFDM demodulation of a signal received from a transmission channel. The inventive method includes performing the fast Fourier transform of the signal received in a window corresponding to a symbol, each symbol being associated with a guard time reproducing one part of the symbol; supplying a set of estimated values for the module impulse response; determining coefficients, each coefficient being obtained from the product of the aforementioned set and a filtering function (FE) for a determined relative position of the filtering function in relation to the set; determining the maximum coefficient and the corresponding relative position; and positioning the window as a function of the relative position, the filtering function including a central part (LMAX) which has a constant amplitude and a duration equal to the duration of the guard time and which is surrounded by non-zero decreasing edges.

Abstract: A COFDM demodulator including a fast Fourier transform circuit receiving a signal on an information channel, the received signal corresponding to a sequence of symbols, each conveying several carriers, some of which are pilots, each carrier of a symbol being modulated in plase and/or in amplitude by a current complex coefficient, the fast Fourier transform circuit providing for each carrier the associated current complex coefficient; a circuit for determining an estimate of the frequency response of the information channel providing, for each pilot, a complex coefficient estimated based on the current complex coefficient associated with the pilot, and a circuit for determining the time variation of the frequency response of the information channel based on the estimated and current complex numbers associated with at least one pilot.

Abstract: A device for suppressing pulse interferences contained in a signal, including a circuit for detecting pulse interferences contained in the signal, and a circuit for correcting the signal disturbed by the detected pulse interferences, in which the detection circuit comprises a circuit for determining a first coefficient representative of a statistical feature of the variation of the signal over a first time period; a circuit for determining a second coefficient representative of a statistical feature of the variation of the signal over a second time period longer than the first time period; and a comparison circuit comparing the first and second coefficients and providing a signal indicative of the presence of a pulse interference over the first time period when the first coefficient clearly differs from the second coefficient.

Abstract: The invention relates to a method for the COFDM demodulation of a signal received from a transmission channel. The inventive method includes performing the fast Fourier transform of the signal received in a window corresponding to a symbol, each symbol being associated with a guard time reproducing one part of the symbol; supplying a set of estimated values for the module impulse response; determining coefficients, each coefficient being obtained from the product of the aforementioned set and a filtering function (FE) for a determined relative position of the filtering function in relation to the set; determining the maximum coefficient and the corresponding relative position; and positioning the window as a function of the relative position, the filtering function including a central part (LMAX) which has a constant amplitude and a duration equal to the duration of the guard time and which is surrounded by non-zero decreasing edges.

Abstract: The invention relates to a method for the COFDM demodulation of a signal received from a transmission channel. The inventive method includes performing the fast Fourier transform of the signal received in a window corresponding to a symbol, each symbol being associated with a guard time reproducing one part of the symbol; supplying a set of estimated values for the module impulse response; determining coefficients, each coefficient being obtained from the product of the aforementioned set and a filtering function (FE) for a determined relative position of the filtering function in relation to the set; determining the maximum coefficient and the corresponding relative position; and positioning the window as a function of the relative position, the filtering function including a central part (LMAX) which has a constant amplitude and a duration equal to the duration of the guard time and which is surrounded by non-zero decreasing edges.

Abstract: The invention relates to a method for the COFDM demodulation of a signal received from a transmission channel. The inventive method includes performing the fast Fourier transform of the signal received in a window corresponding to a symbol, each symbol being associated with a guard time reproducing one part of the symbol; supplying a set of estimated values for the module impulse response; determining coefficients, each coefficient being obtained from the product of the aforementioned set and a filtering function (FE) for a determined relative position of the filtering function in relation to the set; determining the maximum coefficient and the corresponding relative position; and positioning the window as a function of the relative position, the filtering function including a central part (LMAX) which has a constant amplitude and a duration equal to the duration of the guard time and which is surrounded by non-zero decreasing edges.

Abstract: A COFDM demodulator or analogue comprising a fast Fourier transform circuit analyzing a received signal in a window corresponding to a symbol, each symbol conveying several phase- and/or amplitude-modulated carriers, some of which are signaling carriers, and a circuit for positioning said window. The circuit for positioning said window uses the non demodulated signaling carriers.

Abstract: A COFDM demodulator including a fast Fourier transform circuit receiving a signal on an information channel, the received signal corresponding to a sequence of symbols, each conveying several carriers, some of which are pilots, each carrier of a symbol being modulated in phase and/or in amplitude by a current complex coefficient, the fast Fourier transform circuit providing for each carrier the associated current complex coefficient; a circuit for determining an estimate of the frequency response of the information channel providing, for each pilot, a complex coefficient estimated based on the current complex coefficient associated with the pilot; and a circuit for quantizing the time variation of the frequency response of the information channel based on the estimated and current complex numbers associated with at least one pilot.

Abstract: A device for suppressing pulse interferences contained in a signal, including a circuit for detecting pulse interferences contained in the signal, and a circuit for correcting the signal disturbed by the detected pulse interferences, in which the detection circuit comprises a circuit for determining a first coefficient representative of a statistical feature of the variation of the signal over a first time period; a circuit for determining a second coefficient representative of a statistical feature of the variation of the signal over a second time period longer than the first time period; and a comparison circuit comparing the first and second coefficients and providing a signal indicative of the presence of a pulse interference over the first time period when the first coefficient clearly differs from the second coefficient.

Abstract: A COFDM demodulator or analogue comprising a fast Fourier transform circuit analyzing a received signal in a window corresponding to a symbol, each symbol conveying several phase- and/or amplitude-modulated carriers, some of which are signaling carriers, and a circuit for positioning said window. The circuit for positioning said window uses the non demodulated signaling carriers.