St-ericsson Sa

Stmicroelectronics International N.v.

Optis Circuit Technology, LLC

Stmicroelectronics S.r.l.

Stmicroelectronics (rousset) Sas

Stmicroelectronics (grenoble 2) Sas

Stmicroelectronics (alps) Sas

Oct Circuit Technologies International Limited

Achraf Dhayni

Daniele Mangano

Benoit Marchand

Hamilton Emmanuel Querino De Carvalho

Hussein Hijazi

Christophe Arnal

Jeroen Kuenen

The present disclosure relates to an electronic device comprising a first capacitor and a quartz crystal coupled in series between a first node and a second node; an inverter coupled between the first and second nodes; a first variable capacitor coupled between the first node and a third node; and a second variable capacitor coupled between the second node and the third node.

Drift compensation

A device for managing operation of an object capable of contactless communication with a reader magnetically coupled to the object includes a modulator configured to modulate an impedance of a load connected across terminals of an antenna of the object during a transmission phase during which information is transmitted from the object to the reader. The device further includes a monitor configured to carry out a monitoring phase, prior to the transmission phase. The monitoring phase includes a test modulation of the impedance of the load, a monitoring of a level of amplitude modulation of a modulated test signal present at the antenna of the object and resulting from the test modulation, and a capacitive modification of the impedance of the load if this level is lower than a threshold.

Method for managing the operation of an object that is able to contactlessly communicate with a reader

A method for managing the operation of an object capable of contactless communication with a reader magnetically coupled to the object includes a phase for transmission of information from the object to the reader and includes a modulation of the impedance of a load connected across the terminals of the antenna of the object. Prior to the transmission phase, a monitoring phase includes a monitoring of the level of amplitude modulation of a modulated test signal present at the antenna of the object and resulting from a test modulation of the impedance of the load and a capacitive modification of the impedance of the load if this level is lower than a threshold.

A method and an apparatus determine a time of start of series of OFDM symbols forming an OFDM packet, wherein one or more symbols of the OFDM signal includes a plurality of copies of a short training sequence made of a plurality of time-domain samples. The method includes determining a coarse time index, determining a fine time index, and determining the time of start of each OFDM symbols based on the fine time index. The coarse time-domain sample of the coarse time index is within a coarse estimation error interval, and the time-domain samples of the coarse estimation error interval are converted into frequency domain samples. A metric value is determined for each frequency domain samples, and the fine time index is the time index corresponding to one of the coarse estimation error interval having its associated frequency domain sample having the lowest metric value.

OFDM packets time synchronisation

A method for determining a symbol boundary in a data packet belonging to a received OFDM signal is provided. The data packet includes a first training filed and a second training field, which begins with a guard interval. The method includes detecting the beginning of the data packet, and starting an automatic gain control process. The method further includes, after the automatic gain control process is locked, determining autocorrelation peaks and estimating the symbol boundary from times of the autocorrelation peaks.

Coarse symbol boundary detection in OFDM receivers

A Near Field Communication method performed by a tag reader detects whether a tag is present. The method includes stimulating the tag reader's transmitter to generate an impulse response, evaluating the impulse response generated by the transmitter to obtain an evaluated impulse response, and assessing whether a tag is present based on the evaluated impulse response.

Near field communication method of detection of a tag presence by a tag reader

A receiver estimates a vector of emitted symbols over a MIMO transmission channel which is emitted by emitting antennas. The receiver receives a vector of received symbols on receiving antennas. Estimation of the vector of emitted symbols is made by calculating a metric associated with a criterion for each vector of a subset of all possible vectors of emitted symbols and selecting an estimation for said vector of emitted symbols as the vector of emitted symbols among said subset which minimizes said metric.

Low complexity maximum-likelihood-based method for estimating emitted symbols in a SM-MIMO receiver

A built-in self-testing method of a near field communication device including several functions tests a first internal communication link between a first function and a second function. The testing is performed by sending, on said first internal communication link, a first command from said first function used as a transmitter to said second function used as a receiver, and by checking said first command has been correctly executed by said second function.

Built-in self-testing method of a near field communication device

An OFDM communication transceiver, which is configured to test its connection with an antenna circuit unit, has a receiver chain and an emitting chain. The receiver chain includes a time-to-frequency transform unit and the emitting chain includes a frequency-to-time transform unit. The transceiver further includes means for disconnecting the receiver chain to the antenna circuit unit, means for providing a stimulus as input to the emitting chain, means for reintroducing the signal at the output of the emitting chain as an input of the receiving chain, means for determining a circuit resonance frequency, Fr, and a quality factor, Q, of a transfer function computed from the output of the time-to-frequency transform unit, and means for deciding about the connection of said antenna circuit unit according to the resonance frequency and the quality factor.

Built-in self-test technique for detection of imperfectly connected antenna in OFDM transceivers

A system can be used for contactless communication of information between a first device and a second device, each having an antenna intended to be coupled via a near magnetic field. The first device includes a transmit chain having first circuitry configured to generate a digital data stream corresponding to the information to be transmitted, and second circuitry configured to generate a first amplitude-modulated and dithered signal in the antenna of the first device from this stream and from an application of a first dithering. The second device includes a receive chain having third circuitry configured to carry out a frequency transposition of a second amplitude-modulated and dithered signal originating from the first signal, with application of a second dithering synchronous with the first dithering.

Method for a contactless communication between two NFC devices with impact reduction of an external noise emission

A method of determining a calibration of a near field communication, NFC, device, the NFC device comprising a receiver circuit, a transmitter circuit and a load modulator circuit, the method comprising: generating a carrier signal in the transmitter circuit, generating a modulation signal in the load modulator circuit, generating a modulated carrier signal, comprising first and second frequencies, by applying the modulation signal to the carrier signal, applying the modulated carrier signal at an input of the receiver circuit, and determining a response parameter of the receiver circuit on the basis of the response of the receiver circuit to the first and second frequencies in the modulated carrier signal.

On-chip stimulus generation for test and calibration of NFC reader receivers

An emitter for modulating and emitting an orthogonal frequency division multiplexing signal through a transmission channel (TC), comprising a frequency-to-time converter for converting symbols to be transmitted into time symbols, and means for serializing and amplifying said time symbol so as to emit it as an OFDM signal through said transmission channel, said emitter further comprising: means () for clipping said time symbols; time-to-frequency convertor () for converting said time symbols; and means for applying a set of data subcarriers of the outputs of said time-to-frequency converter as inputs of said frequency-to-time converter wherein out-of-band subcarriers are set to zero and the clipping level is set to a minimum level allowing the amplifier to operate in an efficient region.

Reduction of peak-to-average ratio in OFDM systems

A method of self-test for a near-field communication (NFC) radio frequency (RF) front-end unit comprising one antenna driver and at least one unit from a group comprising one reader and one card emulator, the RF front-end unit being connected to a digital front-end unit, wherein the antenna driver and the unit are interconnected through a first connection line via their respective first input-output interface and are also interconnected through a second connection line via their respective second input-output interface, the digital front-end unit being connected to the second connection line, the method comprising: activating the antenna driver and the unit based on control signals; &#x2014;generating a first signal onto the first connection line by modulating a respective first bitstream; &#x2014;retrieving a second bitstream from the second connection line, by demodulating the first signal; and, &#x2014;determining an outcome of the self-test by monitoring the demodulated signal.

Loopback-based built-in-self-test

Receiver (RCV) adapted for compensating for Symbol Timing Offset when receiving OFDM symbols, over a communication channel (TC), comprising: means (REG, DFT, CMP) for detecting a first phase with no Inter-Symbol Interference, means (REG, DFT, CMP) for detecting a second phase with presence of Inter-Symbol Interference, means (REG, DFT, CMP) for compensating for said Symbol Timing Offset by estimating starting points of said received OFDM symbols as being one sample before the start of said second phase. The timing synchronization is achieved in frequency domain by monitoring amplitude variation of the demodulated subcarriers symbols, said variation being due to the presence of Inter Symbol Interference when the FFT window overlaps with the subsequent OFDM symbol.

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Vallauris, France

Achraf Dhayni