Abstract: Disclosed is a sensor measuring patient spine vertebra angular orientation, including: a fastener, adapted to be fastened on a specific patient spine vertebra in a unique orientation relative to the specific vertebra, a support, solidary with the fastener in a unique orientation relative to the fastener, a detector, removably secured to the support in a unique orientation relative to the support and adapted to measure one or more parameters representative of the patient spine vertebra angular orientation.

Abstract: Disclosed is a sensor measuring patient spine vertebra angular orientation, including: a fastener, adapted to be fastened on a specific patient spine vertebra in a unique orientation relative to the specific vertebra, a support, solidary with the fastener in a unique orientation relative to the fastener, a detector, removably secured to the support in a unique orientation relative to the support and adapted to measure one or more parameters representative of the patient spine vertebra angular orientation.

Abstract: A system comprises a cavity being reflecting for RF waves and comprises at least one acoustic wave sensor exhibiting a resonance frequency band, coupled to a sensor antenna; and an interrogation/reception device for the sensor. The interrogation/reception device comprises: means for transmitting/receiving an RF signal transmitting within an interrogation frequency band comprising the resonance frequency band of the sensor; at least a first transmission/reception antenna and a second transmission antenna/reception, positioned within the cavity; means for dividing the signal into at least a first RF signal and a second RF signal, the first signal being transmitted to the first transmission/reception antenna and the second signal being transmitted to the second transmission/reception antenna; means for creating a phase-shift between the first RF signal and the second RF signal; means for analysing the power level of the received signal. An interrogation method used in the system is also provided.

Abstract: A method of interrogating a surface acoustic wave differential sensor formed by two resonators is provided, wherein the method allows the measurement of a physical parameter by determination of the difference between the natural resonant frequencies of the two resonators, which difference is determined on the basis of the analysis of a signal representative of the level of a signal received as echo of an interrogation signal, for a plurality of values of a frequency of the interrogation signal in a domain of predetermined values; the analysis can be based on the cross-correlation of the said signal representative of the level according to a splitting into two distinct frequency sub-bands. An advantage is that it may be implemented in a radio-modem.

Abstract: A system comprises a cavity being reflecting for RF waves and comprises at least one acoustic wave sensor exhibiting a resonance frequency band, coupled to a sensor antenna; and an interrogation/reception device for the sensor. The interrogation/reception device comprises: means for transmitting/receiving an RF signal transmitting within an interrogation frequency band comprising the resonance frequency band of the sensor; at least a first transmission/reception antenna and a second transmission antenna/reception, positioned within the cavity; means for dividing the signal into at least a first RF signal and a second RF signal, the first signal being transmitted to the first transmission/reception antenna and the second signal being transmitted to the second transmission/reception antenna; means for creating a phase-shift between the first RF signal and the second RF signal; means for analysing the power level of the received signal. An interrogation method used in the system is also provided.

Abstract: A method of interrogating a surface acoustic wave differential sensor formed by two resonators is provided, wherein the method allows the measurement of a physical parameter by determination of the difference between the natural resonant frequencies of the two resonators, which difference is determined on the basis of the analysis of a signal representative of the level of a signal received as echo of an interrogation signal, for a plurality of values of a frequency of the interrogation signal in a domain of predetermined values; the analysis can be based on the cross-correlation of the said signal representative of the level according to a splitting into two distinct frequency sub-bands. An advantage is that it may be implemented in a radio-modem.

Abstract: A method of remotely interrogating a passive sensor, comprising at least one resonator, so as to determine the resonant frequency of said resonator, having a resonant frequency response defined by the design of said resonator, includes: a preliminary frequency-scan step for interrogating said resonator over a frequency range allowing for the rapid determination of a first resonant frequency (fr0) of said resonator by detecting the amplitude of the response signal of said resonator; a first step of a first couple of interrogations of said resonator at a first frequency (f11) and a second frequency (f21) such that: f11=fr0?fm/2 and f21=fr0+fm/2, fm being smaller than the width at half-maximum of the resonant frequency response defined by the design, allowing a first couple of amplitudes (Pf11, Pf21) of first and second reception signals to be defined; a second step of determining the amplitude difference (?(Pf11?Pf21)), said difference being signed; a third step allowing a first resonant frequency (fr1), contro

Abstract: A method of remotely interrogating a passive sensor, comprising at least one resonator, so as to determine the resonant frequency of said resonator, having a resonant frequency response defined by the design of said resonator, includes: a preliminary frequency-scan step for interrogating said resonator over a frequency range allowing for the rapid determination of a first resonant frequency (fr0) of said resonator by detecting the amplitude of the response signal of said resonator; a first step of a first couple of interrogations of said resonator at a first frequency (f11) and a second frequency (f21) such that: f11=fr0?fm/2 and f21=fr0+fm/2, fm being smaller than the width at half-maximum of the resonant frequency response defined by the design, allowing a first couple of amplitudes (Pf11, Pf21) of first and second reception signals to be defined; a second step of determining the amplitude difference (?(Pf11?Pf21)), said difference being signed; a third step allowing a first resonant frequency (fr1), contro