An antenna device has a radiating unit having a plurality of antennas, configured to emit a radio signal with a radiation pattern. In addition, the antenna device has a calculator configured to generate and to apply to the plurality of antennas a plurality of feed signals based on an identification signal provided in order to generate the radio signal. The calculator is additionally configured to control the feed signals in a time-varying manner so that the radio signal is emitted with a time-varying radiation pattern.

The present disclosure relates to a method implemented by a first NFC device, wherein the establishment of a transaction with a second NFC device configured in reader mode is performed when the signal level received by the first device, configured in card mode, reaches a first threshold, depending on the type of modulation technology of the second device.

A license detector system enables a person such as a police officer to monitor vehicles on the road to ensure drivers have valid licenses. Within each valid license is an RFID tag which contains specific information and each RFID tag is able to send that information to a detector when requested. To use the system, the police officer aims the detector at a vehicle, initiates the signal to be received by the RFID tag within the license and waits to receive a signal back from the RFID tag. If a signal is received, then a valid license has been detected within the vehicle. However, if no signal or an invalid signal is received by the detector, then no one, specifically the driver of the car, has a valid license. Upon discovering such information, the police officer should be justified in stopping the vehicle and taking the necessary police action.

A vehicle power system includes a plurality of power distribution divisions, a rechargeable energy storage system, switching devices for connection of the power distribution divisions to the rechargeable energy storage system, a plurality of loads energized from the power distribution divisions, a control network including nodes for control over the loads and the switching devices, a mobile transponder and a transceiver which is connected to the controller area network and which provides for communicating with the transponder. Sensors monitored by the controller area network and proximity of the mobile transponder determine a state for vehicle power distribution system.

A method is provided for differentiating one of a plurality of unpowered NFC transmitting devices for NFC communication with a receiving device. Each NFC transmitting device has a transmitter NFC interface and an NFC communication range. A range extending device has a power source, a transmitter communication interface, a range extender antenna, and an amplifier. One of the transmitting devices is selected and the range extending device is connected to it so that the transmitter communication interface engages the transmitter NFC interface of the selected transmitting device. This action serves to establish an extended communication range for the selected NFC transmitting device. The NFC transmitting devices are then positioned at a distance from the receiving device that is within the extended communication range, but outside the communication ranges of the other NFC transmitting devices. NFC communication is then established between the selected NFC transmitting device and the receiving device.

A contactless communication method comprises retro-modulation of a carrier signal received at the terminals of an antenna in an alternation of modulated states and unmodulated states. The modulated state comprises a modulation of a load at the terminals of the antenna at zero impedance, and the transitions from the modulated state to the unmodulated state are controlled at an instant determined by a first delay.

A first object and a second object are movable in relation to one another. The first object includes a transponder using an integrated circuit having two terminals which may or may not be shorted. The presence or absence of a short circuit between the two terminals is detected. This is accomplished at least partly by the second object depending on the relative positioning of the first and second objects. The transponder transmits, to a module having a contactless reader function, positioning information corresponding to said relative positioning using a contactless communication protocol.

Techniques are described for accurate tracking of a radiofrequency (RF) carrier for amplitude-modulated signals in unstable reference clock environments. For example, some embodiments operate in context of clock circuits in devices configured for near-field communication (NFC) card emulation (CE) mode. The clock circuits seek to generate an internal clocking signal by tracking a clock reference, such as an RF carrier. In some cases, the clock reference can unpredictably become unreliable for periods of time, during which continued tracking of the unreliable clock reference and/or improper reacquisition can yield appreciable frequency and phase errors in the generated internal clocking signal. Some embodiments implement phase delta detection with time limiting to limit the magnitude of such errors in the internal clocking signal introduced while tracking an unreliable clock reference. Other embodiments provide feedback-pause-control (FPC) to force proper clock reference reacquisition. Such FPC can be implemented additionally with time-limited phase detection.

In an embodiment an apparatus includes a contactless transponder including a contactless interface and a wired interface, wherein the contactless transponder is configured to communicate with a contactless reader according to a contactless protocol through the contactless interface, a wired communication bus connected to the wired interface and at least one module connected to the bus, wherein the transponder is configured so that the reader is a master on the bus when the reader and the transponder communicate.

There is described a method of determining a phase value for an NFC card emulating device that enables said NFC card emulating device to communicate in phase with an NFC reader device while utilizing active load modulation, wherein the NFC card emulating device comprises a card antenna and the NFC reader device comprises a reader antenna, the method comprising receiving a reader signal from the NFC reader device at the NFC card emulating device through coupling of the card antenna and the reader antenna, the reader signal comprising a subcarrier modulation; estimating a resonance frequency of a system corresponding to the coupled card antenna and reader antenna based on the received communication signal; and determining the phase value based on the estimated resonance frequency and a set of parameters that represents a predetermined reference system. Furthermore, an NFC card emulating device, an NFC system, and a computer program are described.