Abstract: A method for phase modulation of a carrier signal from a transmitter to a contactless transponder in which data is coded as consecutive symbols, each corresponding to a predefined number of carrier cycles, and in which a symbol time is at least two cycles of the carrier signal includes, at the transmitter, spreading a phase jump of a symbol in relation to a preceding symbol over a first part of the symbol time. The establishment of the phase jump is completed in the first part of the symbol time. The periods of the cycles are constant during a second part of the symbol time.

Abstract: This method for estimating a carrier-frequency offset in a telecommunication signals receiver comprises the following steps: computation of the partial correlations relating to several successive portions of a reference binary sequence, each partial correlation being computed between a portion of a signal received by the receiver at said carrier frequency, this signal comprising said reference binary sequence, and a predetermined portion of said reference binary sequence stored and/or generated by the receiver, in several possible relative positions between the received signal and the predetermined portion, and determination of the carrier-frequency offset from the computed partial correlations. It also comprises a step of selecting a synchronization position and the determination step comprises the estimation of a phase shift between computed partial correlations at the selected synchronization position.

Abstract: A method for phase modulation of a carrier signal from a transmitter to a contactless transponder in which data is coded as consecutive symbols, each corresponding to a predefined number of carrier cycles, and in which a symbol time is at least two cycles of the carrier signal includes, at the transmitter, spreading a phase jump of a symbol in relation to a preceding symbol over a first part of the symbol time. The establishment of the phase jump is completed in the first part of the symbol time. The periods of the cycles are constant during a second part of the symbol time.

Abstract: The invention relates to a method for demodulating information emitted by amplitude modulation with two levels by a reader (2) to a transponder (4), comprising a step to determine if this symbol is identical to or is different from the previous symbol, after each symbol.

Abstract: This method for estimating a carrier-frequency offset (?f) in a telecommunication signals receiver comprises the following steps: computation (10) of the partial correlations relating to several successive portions of a reference binary sequence, each partial correlation being computed between a portion of a signal received by the receiver at said carrier frequency, this signal comprising said reference binary sequence, and a predetermined portion of said reference binary sequence stored and/or generated by the receiver, in several possible relative positions between the received signal and the predetermined portion, and determination (14, 16) of the carrier-frequency offset (?f) from the computed partial correlations. It also comprises a step (12) of selecting a synchronization position and the determination step comprises the estimation (14) of a phase shift between computed partial correlations at the selected synchronization position.

Abstract: The invention relates to a method for demodulating information emitted by amplitude modulation by a reader (2) to a transponder (4) comprising: a step to compare variations of a slaving voltage (Vc) of the transponder (4) with threshold values, and to transform the result of this comparison into an authorized modulation level skip value, a step to add this skip to a previous first modulation level to determine a second modulation level.

Abstract: A method for secured communication between a transmitter (10) and a receiver (1) in which a range of power levels transmitted by the transmitter (10) a range of frequencies inside which the transmission will occur, (10) are known or detectable by the receiver (1), the method including transmission by the receiver (1) of a power supply signal for the transmitter characterized in that the receiver (I) transmits for at least the whole duration of the transmission, a noise signal which buries the transmission signal, the receiver (1) subtracts from the received signal, the noise signal in order to obtain a useful signal. The invention also includes a receiving device operating according to the method.

Abstract: The invention relates to a method for demodulating information emitted by amplitude modulation by a reader (2) to a transponder (4) comprising: a step to compare variations of a slaving voltage (Vc) of the transponder (4) with threshold values, and to transform the result of this comparison into an authorized modulation level skip value, a step to add this skip to a previous first modulation level to determine a second modulation level.

Abstract: The invention relates to a method for demodulating information emitted by amplitude modulation with two levels by a reader (2) to a transponder (4), comprising a step to determine if this symbol is identical to or is different from the previous symbol, after each symbol.