Abstract: An interferometric measurement method aims at calculating angular misalignment between fiber and ferrule axes for single fiber ferrules. The misalignment is measured by scanning side surface of reference fiber inserted into the ferrule and side surface of the ferrule. For single fiber connectors and ferrules, the method also aims at calculating fiber core concentricity and ferrule circularity and for single fiber connectors, end face angle of polish. The concentricity, the circularity and the angle of polish are measured by scanning side surface of the ferrule and end face of the connector or ferrule. Interferometric data from the side surfaces of the reference fiber and the ferrule, or from the end face of the connector or ferrule and the side surface of the ferrule, is gathered during one scanning session—either one simultaneous scan or several scans without moving or re-inserting the connector or ferrule.

Abstract: A design method for a phase-locked loop comprises: a controlled-frequency oscillator; a phase comparator, to determine a phase difference between an output signal of the controlled-frequency oscillator and a reference signal; a corrector to receive as input a signal representative of the phase difference and to generate at its output a first correction signal; at least one second corrector, to receive as input a signal representative of or affected by a phase noise of the reference signal or of the output signal of the controlled-frequency oscillator and to generate at its output a second correction signal; and a circuit for generating a slaving signal for the controlled-frequency oscillator on the basis of the first and second correction signals; the method using the H-infinity method. Method for fabricating such a loop comprising a design step implementing this method. Phase-locked loop thus obtained.

Abstract: An interferometric measurement method aims at calculating angular misalignment between fiber and ferrule axes for single fiber ferrules. The misalignment is measured by scanning side surface of reference fiber inserted into the ferrule and side surface of the ferrule. For single fiber connectors and ferrules, the method also aims at calculating fiber core concentricity and ferrule circularity and for single fiber connectors, end face angle of polish. The concentricity, the circularity and the angle of polish are measured by scanning side surface of the ferrule and end face of the connector or ferrule. Interferometric data from the side surfaces of the reference fiber and the ferrule, or from the end face of the connector or ferrule and the side surface of the ferrule, is gathered during one scanning session—either one simultaneous scan or several scans without moving or re-inserting the connector or ferrule.

Abstract: A design method for a phase-locked loop comprises: a controlled-frequency oscillator; a phase comparator, to determine a phase difference between an output signal of the controlled-frequency oscillator and a reference signal; a corrector to receive as input a signal representative of the phase difference and to generate at its output a first correction signal; at least one second corrector, to receive as input a signal representative of or affected by a phase noise of the reference signal or of the output signal of the controlled-frequency oscillator and to generate at its output a second correction signal; and a circuit for generating a slaving signal for the controlled-frequency oscillator on the basis of the first and second correction signals; the method using the H-infinity method. Method for fabricating such a loop comprising a design step implementing this method. Phase-locked loop thus obtained.

Abstract: A device for generating a clock signal, including a phase-locked loop including: a controlled oscillator to deliver a clock signal; plural phase comparators to compare a phase of the clock signal delivered by the controlled oscillator with plural clock signal phases applied at an input of the phase-locked loop; a mechanism for weighted summation of output signals of the plural phase comparators such that one or more of the weighting coefficients applied to one of the output signals has an absolute value that overrides the absolute values of the other weighting coefficients applied to the other output signals; and a mechanism filtering the weighted sum of the output signals of the plural phase comparators, to deliver at an output a control signal to the controlled oscillator.

Abstract: A device for compensating a delay ? suffered by a first periodic signal ref(t) during propagation between a first and second end of a first transmission connection, comprising at least: first means able to generate a second signal ref(t+?) corresponding to the first signal ref(t) the phase of which is advanced by a time equal to the delay ?, second means able to generate, from a third signal ref(t??) obtained at the second end of the first transmission connection and corresponding to the first signal ref(t) the phase of which is delayed by the delay ?, and from the second signal ref(t+?), a fourth signal in phase with the first signal ref(t).

Abstract: A device for generating a clock signal, including a phase-locked loop including: a controlled oscillator to deliver a clock signal; plural phase comparators to compare a phase of the clock signal delivered by the controlled oscillator with plural clock signal phases applied at an input of the phase-locked loop; a mechanism for weighted summation of output signals of the plural phase comparators such that one or more of the weighting coefficients applied to one of the output signals has an absolute value that overrides the absolute values of the other weighting coefficients applied to the other output signals; and a mechanism filtering the weighted sum of the output signals of the plural phase comparators, to deliver at an output a control signal to the controlled oscillator.

Abstract: A device for compensating a delay ? suffered by a first periodic signal ref(t) during propagation between a first and second end of a first transmission connection, comprising at least: first means able to generate a second signal ref(t+?) corresponding to the first signal ref(t) the phase of which is advanced by a time equal to the delay ?, second means able to generate, from a third signal ref(t??) obtained at the second end of the first transmission connection and corresponding to the first signal ref(t) the phase of which is delayed by the delay ?, and from the second signal ref(t+?), a fourth signal in phase with the first signal ref(t).