Commissariat a L'energie Atomique

Commissariat a L'energie Atomique Et Aux Energies Alternatives

Jacques Reverdy

Elisabeth Crochon

Thierry Thomas

Gérard Robert

Florian Pebay-Peyroula

François Dehmas

Sylvain Bacquet

Gilles Masson

Francois Dehmas

Yann Têtu

Ricardo Malherbi Martins

A system for detecting a specific relative position between a reader and a receiver, including: an inductive contactless receiver including an antenna winding and a circuit for selectively modulating a load; an inductive contactless reader including: a transceiver antenna circuit having nonzero mutual inductance with the antenna winding for the position, a communication circuit connected to the transceiver antenna circuit, a receiver antenna circuit having mutual inductance with the antenna winding that exhibits a minimum for the position, and a processing circuit for: identifying presence of a receiver by detecting nonzero mutual inductance between the transceiver antenna circuit and an antenna winding, and detecting a mutual inductance minimum between the receiver antenna circuit and an antenna winding.

Method and system for detecting a specific relative position between two objects

This fluid pressure sensor includes a coil the self inductance of which varies as a function of the pressure of a fluid inside the flexible pipe. This coil includes a turn including:

Fluid pressure sensor

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.

Method for the phase modulation of a carrier signal transmitted from a transmitter to a contactless transponder, and device for implementing same

The invention relates to a method for encoding contactless communication data from a transponder to a reader via charge modulation, in the form of a set of modulation patterns, each modulation pattern being a series of charge levels of a predefined length used for physical encoding, having a duration of n carrier periods (T), including a series of at least two charge levels, having a minimum pulse width (w) corresponding to the shortest duration of a single charge level in the pattern, and having a retromodulation rate (t) corresponding to the ratio between the retromodulation time and the duration of a pattern, characterized in that the number (k) of patterns is greater than four, the minimum pulse widths (w) of at least two patterns are different, and the retromodulation rates (t) of at least two patterns are different. The invention also relates to a device for implementing the method.

Method for encoding contactless communication data from a transponder to a reader via charge modulation, in the form of a set of patterns and device for implementing same

A transponder of a contactless data exchange system includes a unit to receive and transmit data provided with at least one first antenna loop and at least one second antenna loop in order to carry out a coupling with a reader. The transponder includes a phase shifter to shift a signal coming from the second loop by a phase shift of K*&#x3c0;, K being an odd integer greater than 0, to produce a phase shifted signal. The transponder includes an adder, to add a signal coming from said first loop and the phase shifted signal to produce a sum signal. The transponder also includes a unit to authorize or prevent a data transmission, depending on the sum signal. A reader of a contactless data exchange system includes a data sending/receiving unit provided with at least one antenna loop, at least one other antenna loop, and a phase shifter.

Device for the secure contactless data exchange between a reader and a card

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

Two-level demodulation method and device

The invention relates to a device for demodulating an input signal containing information being conveyed by phase modulation of a carrier wave. A transmitter generates a signal controlling a phase variation in the carrier wave, for each symbol having N cycles, N being an integer strictly greater than 1. The phase variation stretches on the receiver side over n cycles, n being an integer greater than 1 and less than N. The device generates a single pulse for each symbol received suited to generate the leading edge of the pulse corresponding to the symbol considered after a constant duration from the moment the symbol considered starts; and generates the trailing edge of the pulse considered at a moment the phase shift corresponding to the symbol considered has to be measured. Conversion means generate an output signal with a voltage varying as a function of the duration of the pulse produced.

Device for demodulating a signal containing information being conveyed by phase shift keying

The invention relates to a method for demodulating information emitted by amplitude modulation by a reader () to a transponder () comprising:

Multi-level demodulation method and device

A device and method for estimating a phase reference or a phase shift of a Swith respect to another reference signal S.

Device and method for detecting the phase of a signal

Each device () comprises a processing circuit connected to a first antenna (), designed to be coupled to an external antenna (), and a second antenna () designed to be coupled to an antenna () of a higher-ranking device (). The system comprises a reading unit and devices () having a predetermined ranking. The first antenna () of the rank one device () is coupled to an antenna () of the reading unit. Addressing by the reading unit of a device () ranking higher than one is performed by means of the associated lower-ranking devices (). A device () of predetermined ranking is associated with a sub-set () of higher-ranking devices () so as to form a hierarchical tree structure.

System comprising a plurality of devices that can be addressed by radio frequency, and method for addressing by activation of a transparent mode

Labels (E) are identified by an interrogating system ( ) in the order of their arrival in an interrogation field ( ), which initializes and starts up a time counter ( ) operated so as to prioritize the oldest label during identification. This prevents labels (E) passing through the interrogation field ( ) without being able to transmit their identification code.

Growing community of inventors

Crolles, France

Jacques Reverdy