Abstract: Embodiments of an antenna system and a method for operating an antenna are disclosed. In an embodiment, an antenna system includes a first ferrite element, a second ferrite element, a first coil wrapped around the first ferrite element, a second coil wrapped around the second ferrite element, a first antenna interface electrically coupled to the first coil, a second antenna interface electrically coupled to the second coil, and a conductor network connected between the first coil, the second coil, the first antenna interface, and the second antenna interface.

Abstract: A wireless charging (WLC) poller device and WLC listener device are provided. A method for performing a presence check of the WLC listener device includes providing a radio frequency (RF) presence check signal. An input signal from the antenna by the poller device is received concurrently with the transmission of the RF presence check signal. A rate of change of a magnitude of the input signal is measured during the transmission of the presence check signal. A difference between the input signal and an expected input signal is determined. A presence of the listener device is detected if an absolute value of the measured rate of change of the input signal is above a threshold rate of change, and the difference between the input signal and the expected input signal is within a predetermined distance. Prior to the presence check, a capacitor of the WLC listener device may be discharged.

Abstract: There is described a method of operating an NFC device, the method comprising: determining a resonance frequency of a matching network of the NFC device; modulating, by a modulator, a carrier signal received from an external reader, resulting in a modulated carrier signal; controlling, using a controller, a transmission of the modulated carrier signal to the external reader; and transmitting, by a transmitter driver, said modulated carrier signal, said transmitter driver having at least one configurable setting that influences a damping behavior of the transmitted modulated carrier signal, wherein, during a modulation phase of the NFC device, the controller selects and applies the at least one configurable setting based on the determined resonance frequency such that a clock synchronization window is widened. Furthermore, a corresponding NFC device is described.

Abstract: Embodiments of an antenna system and a method for operating an antenna are disclosed. In an embodiment, an antenna system includes a first ferrite element, a second ferrite element, a first coil wrapped around the first ferrite element, a second coil wrapped around the second ferrite element, a first antenna interface electrically coupled to the first coil, a second antenna interface electrically coupled to the second coil, and a conductor network connected between the first coil, the second coil, the first antenna interface, and the second antenna interface.

Abstract: Embodiments of a power amplifier and method of operating a power amplifier are disclosed. In one embodiment, a power amplifier includes a pulse wave modulation (PWM) controller, a first power control stage configured to drive a first output between VDD and VSS in response to a control signal from the PWM controller, a second power control stage configured to drive a second output between VDD and VSS in response to a control signal from the PWM controller, and a mid-voltage control circuit configured to hold the voltage of the first output at a mid-voltage that is between VDD and VSS during an interval between when the first output is driven between VDD and VSS and hold the voltage of the second output at the mid-voltage during an interval between when the first output is driven between VDD and VSS.

Abstract: A near field communication (NFC) device capable of operating by being powered by the field includes an NFC module for generating an electromagnetic carrier signal and modulating the carrier signal according to data to be transmitted, and an antenna circuit coupled to and driven by said NFC module with the modulated carrier signal. The device includes an RF front end coupled between said NFC module and said antenna circuit. The RF front end includes a balanced to unbalanced (Balun) transformer and a tuning capacitor to provide a function of an electromagnetic compatibility (EMC) filter. A powered by the field circuit of the NFC device is adapted to harvest energy from an external field to power said NFC device. The power by the field circuit is coupled to said Balun transformer via one or more impedance elements.

Abstract: In accordance with a first aspect of the present disclosure, a near field communication (NFC) device is provided, comprising: a modulator configured to modulate a carrier signal received from an external reader, resulting in a modulated carrier signal; a controller configured to control a transmission of the modulated carrier signal to the external reader; a transmitter driver configured to transmit said modulated carrier signal, said transmitter driver having a variable resistance; wherein the controller is further configured to change said variable resistance during a modulation phase of the NFC device such that a clock synchronization window is widened. In accordance with a second aspect of the present disclosure, a corresponding method of operating an NFC device is conceived. In accordance with a third aspect of the present disclosure, a non-transitory machine-readable medium is provided, comprising instructions which, when executed, carry out a method of the kind set forth.

Abstract: In accordance with a first aspect of the present disclosure, an active load modulation (ALM) transceiver is provided, comprising a transmitter configured to send a transmit signal to an external device, wherein the transceiver is configured to adjust one or more parameters of the transmit signal at the end of at least one burst of said transmit signal. In accordance with a second aspect of the present disclosure, a method of operating an active load modulation (ALM) transceiver is conceived, comprising sending, by a transmitter of the transceiver, a transmit signal to an external device, and adjusting, by the transceiver, one or more parameters of the transmit signal at the end of at least one burst of said transmit signal.

Abstract: In accordance with a first aspect of the present disclosure, a near field communication (NFC) device is provided, comprising: a modulator configured to modulate a carrier signal received from an external reader, resulting in a modulated carrier signal; a controller configured to control a transmission of the modulated carrier signal to the external reader; a transmitter driver configured to transmit said modulated carrier signal, said transmitter driver having a variable resistance; wherein the controller is further configured to change said variable resistance during a modulation phase of the NFC device such that a clock synchronization window is widened. In accordance with a second aspect of the present disclosure, a corresponding method of operating an NFC device is conceived. In accordance with a third aspect of the present disclosure, a non-transitory machine-readable medium is provided, comprising instructions which, when executed, carry out a method of the kind set forth.

Abstract: Embodiments of methods for determining a location of a mobile device, a mobile device, and a location beacon system are described. In an embodiment, a method for determining a location of a mobile device involves receiving, at a dual-antenna receiver of the mobile device, a plurality of ultra wide band (UWB) signals from a group of unsynchronized beacons having a quadrilateral formation, at the mobile device, determining angle of arrival (AoA) information from the UWB signals, and at the mobile device, calculating the location of the mobile device based on the AoA information. Other embodiments are also described.

Abstract: Embodiments of methods and systems for operating a communications device that communicates via inductive coupling are described. In an embodiment, a method for operating a communications device that communicates via inductive coupling involves adjusting a configuration of the communications device in response to a clock signal that is synchronized to a received clock signal, obtaining information that corresponds to transmission current or power generated in response to the adjusted configuration, and quantifying a detuning condition in response to the obtained information. Other embodiments are also described.

Abstract: Embodiments of a power amplifier and method of operating a power amplifier are disclosed. In one embodiment, a power amplifier includes a pulse wave modulation (PWM) controller, a first power control stage configured to drive a first output between VDD and VSS in response to a control signal from the PWM controller, a second power control stage configured to drive a second output between VDD and VSS in response to a control signal from the PWM controller, and a mid-voltage control circuit configured to hold the voltage of the first output at a mid-voltage that is between VDD and VSS during an interval between when the first output is driven between VDD and VSS and hold the voltage of the second output at the mid-voltage during an interval between when the first output is driven between VDD and VSS.

Abstract: A near field communication (NFC) device capable of operating by being powered by the field includes an NFC module for generating an electromagnetic carrier signal and modulating the carrier signal according to data to be transmitted, and an antenna circuit coupled to and driven by said NFC module with the modulated carrier signal. The device includes an RF front end coupled between said NFC module and said antenna circuit. The RF front end includes a balanced to unbalanced (Balun) transformer and a tuning capacitor to provide a function of an electromagnetic compatibility (EMC) filter. A powered by the field circuit of the NFC device is adapted to harvest energy from an external field to power said NFC device. The power by the field circuit is coupled to said Balun transformer via one or more impedance elements.

Abstract: Embodiments of methods and systems for operating a communications device that communicates via inductive coupling are described. In an embodiment, a method for operating a communications device that communicates via inductive coupling involves obtaining transmission output power information related to the communications device and measuring a detuning condition based on the transmission output power information. Other embodiments are also described.

Abstract: A near field communication (NFC) device capable of operating by being powered by the field includes an NFC module for generating an electromagnetic carrier signal and modulating the carrier signal, and an antenna circuit coupled to and driven by said NFC module with the modulated carrier signal. A differential power combiner circuit is coupled to said NFC module via output terminals of said NFC module. A powered by the field circuit of the NFC device is adapted to harvest energy from an external field to power said NFC device. The power by the field circuit has a first terminal coupled to an output of said differential power combiner circuit via a first impedance block and a second terminal coupled to an input of said antenna circuit via a second impedance block. The NFC device is adapted to be able to operate in a powered by the field card mode.

Abstract: In accordance with a first aspect of the present disclosure, an active load modulation (ALM) transceiver is provided, comprising a transmitter configured to send a transmit signal to an external device, wherein the transceiver is configured to adjust one or more parameters of the transmit signal at the end of at least one burst of said transmit signal. In accordance with a second aspect of the present disclosure, a method of operating an active load modulation (ALM) transceiver is conceived, comprising sending, by a transmitter of the transceiver, a transmit signal to an external device, and adjusting, by the transceiver, one or more parameters of the transmit signal at the end of at least one burst of said transmit signal.

Abstract: Embodiments of methods for determining a location of a mobile device, a mobile device, and a location beacon system are described. In an embodiment, a method for determining a location of a mobile device involves receiving, at a dual-antenna receiver of the mobile device, a plurality of ultra wide band (UWB) signals from a group of unsynchronized beacons having a quadrilateral formation, at the mobile device, determining angle of arrival (AoA) information from the UWB signals, and at the mobile device, calculating the location of the mobile device based on the AoA information. Other embodiments are also described.

Abstract: Embodiments of methods and systems for operating a communications device that communicates via inductive coupling are described. In an embodiment, a method for operating a communications device that communicates via inductive coupling involves adjusting a configuration of the communications device in response to a clock signal that is synchronized to a received clock signal, obtaining information that corresponds to transmission current or power generated in response to the adjusted configuration, and quantifying a detuning condition in response to the obtained information. Other embodiments are also described.

Abstract: A method for compensating phase shift is provided. The method includes sweeping a transmitter (TX) clock frequency over a frequency range and sampling resistance values at a receiver (RX) circuit while sweeping the TX clock frequency. A first frequency in the frequency range is determined which corresponds to a maximum resistance value sampled at the RX circuit. Using a look-up table (LUT), a phase adjust value is determined based on the first frequency. A phase of the TX clock is adjusted based on the phase adjust value.

Abstract: A near field communication (NFC) device capable of operating by being powered by the field includes an NFC module for generating an electromagnetic carrier signal and modulating the carrier signal according to data to be transmitted, and an antenna circuit coupled to and driven by said NFC module with the modulated carrier signal. An electromagnetic compatibility (EMC) filter of the NFC device is coupled to the NFC module via output terminals of said NFC module. A powered by the field circuit of the NFC device is adapted to harvest energy from an external field to power said NFC device. The power by the field circuit is coupled to said EMC filter via one or more impedance elements. The NFC device is adapted to be able to operate in one of a reader mode, a battery supplied card mode, and a powered by the field card mode.