Methods for determining a range rate of a backscatter transponder and readers implementing the methods are described. The reader transmits a continuous wave signal and receives a modulated reflected response signal from the transponder, mixes the modulated reflected response signal with the carrier frequency to produce a downconverted signal, bandpass filters the downconverted signal to pass a bandpass filtered signal containing at least the modulation frequency, applies a non-linear amplitude transfer function to produce a modulation-suppressed signal, and measures the frequency of the modulation-suppressed signal and determines the range rate from the measured frequency.

In embodiments of RFID-based location determination for antenna power adjustment, a mobile device includes a RFID reader to interrogate and communicate with RFID tags. A control module can utilize a learning algorithm to determine a current location of the mobile device based on physical locations associated with the RFID tags, and an antenna power of a wireless transceiver can be adjusted for a signal strength of a wireless network based on the current location of the mobile device. The learning algorithm can maintain a database that includes information about particular locations or rooms within a residence, the signal strength of wireless networks at the locations, and identifiers of the RFID tags. The learning algorithm can learn context of a user's location with the mobile device to improve utilization of the antenna power of the wireless transceiver, and conserve battery power of the mobile device.

A calibration circuit includes a single-wire memory and a transmission line. The single-wire memory includes a power/interrogation terminal and a ground terminal. The single-wire memory is configured to store calibration data for a sensor. The transmission line is configured to be coupled between the sensor and a sensor reader. The transmission line includes first and second conductors. The first conductor is coupled to the power/interrogation terminal and is configured to provide the calibration data and a sensor output signal to the sensor reader. The second conductor is coupled to the ground terminal and is configured to provide a ground reference for the first conductor, the single-wire memory, and the sensor.

Various embodiments illustrated herein disclose a computing device comprising a wake-up detect circuit configured to detect a state change of a link light emitting diode (LED) associated with the computing device. The wake-up detect circuit is configured to transmit a wakeup trigger signal to a processor to transit from a sleep mode to a wake-up mode in response to the detection of the state change of the link LED. The processor is configured to establish a connection between the computing device and another computing device via a communication link in the wake-up mode, the other computing device corresponds to a device that has caused the state change of the link LED.

Techniques for improving energy efficiency of a Radio-Frequency Identification (RFID) reader are described herein. A power control algorithm controlling a power amplifier of the RFID reader adjusts a bias setting of the power amplifier at different time periods during operation of the RFID reader. Particularly, in aspects, the power control algorithm biases the power amplifier at a first bias setting during a first time period when the RFID reader transmits a modulated continuous waveform conveying information to RFID tags in an environment, and biases the power amplifier at a second, different bias setting during a second time period when the RFID reader transmits an unmodulated continuous waveform. By adjusting to the second bias setting, the power control algorithm improves energy/power efficiency of the RFID reader during the second time period, thereby extending the single-charge lifetime of the RFID reader when implemented as a battery powered unit.

A method implemented in a near-field communication system (100), for detecting the presence of a radio-frequency transponder (110) by means of a radio-frequency reader (120) on board a motor vehicle, said radio-frequency transponder (110) being carried in use by a user located outside the vehicle, and said radio-frequency reader (120) being intended to communicate with the radio-frequency transponder (110) so as to control access to the motor vehicle, the method comprising the following steps implemented by the radio-frequency reader: transmitting a radio-frequency interrogation signal; then transmitting a radio-frequency supply signal, intended to be received then modulated by the radio-frequency transponder; detecting the presence of the radio-frequency transponder (110) by measuring an amplitude of the radio-frequency supply signal and comparing it with at least one predetermined threshold.

There are provided ambient internet of things (A-IoT) devices and methods of operation of same. Some embodiments relate to A-IoT device capabilities in relation to energy storage and energy harvesting. Some embodiments, relate to a harmonizing protocol for heterogenous A-IoT device types. Some embodiments, relate to uneven transmission power capabilities of A-IoT devices. Some embodiments relate to the control of carrier wave generation enabling transmission by some A-IoT device configurations. Some embodiments, relate to considering congestion control as it can relate to A-IoT devices.

Techniques for improving energy efficiency of a Radio-Frequency Identification (RFID) reader are described herein. A power control algorithm controlling a power amplifier of the RFID reader adjusts a bias setting of the power amplifier at different time periods during operation of the RFID reader. Particularly, in aspects, the power control algorithm biases the power amplifier at a first bias setting during a first time period when the RFID reader transmits a modulated continuous waveform conveying information to RFID tags in an environment, and biases the power amplifier at a second, different bias setting during a second time period when the RFID reader transmits an unmodulated continuous waveform. By adjusting to the second bias setting, the power control algorithm improves energy/power efficiency of the RFID reader during the second time period, thereby extending the single-charge lifetime of the RFID reader when implemented as a battery powered unit.

One or more embodiments of this specification provide near field communication methods and devices. The near field communication device can detect a probing signal transmitted by a card reader device in a low power card detection mode; and transmit a disturbance signal when detecting that a transmission status of the first probing signal satisfies a condition for signal interference superposition, so that interference superposition is performed between the disturbance signal and the first probing signal, and then the card reader device is triggered to exit the low power card detection mode.

Product scanner based radar systems are provided herein. An example product scanner includes a housing, an indicia scanner, and a radar system further comprising a radar chip and an antenna. In the example, the indicia scanner is configured to capture indicia data from a product indicia disposed within an indicia scan region defined by an optical field-of-view of the optical sensor. In the example, the radar system is configured to capture first three-dimensional layer data representative of an exterior feature of a product disposed within a radar field-of-view. In the example, the radar system is configured to capture second three-dimensional layer data representative of an interior feature of the product disposed within the radar field-of-view.