A resonant structure includes a conductive surface layer on a dielectric layer that produces an enhanced or reduced backscattered radiation in one or more resonant frequency bands when illuminated with electromagnetic energy. A transmitter illuminates the resonant structure with the electromagnetic energy at a first angle relative to the normal of the conductive surface. A receiver is operable to detect the enhanced or reduced backscattered radiation at the resonant frequency bands at a second angle relative to the normal of the conductive surface. The second angle is different from the first angle by at least five degrees. A processor coupled to the receiver and is operable to detect data encoded in one or both of a frequency response and a polarization response of the resonant structure based on the detected enhanced or reduced backscattered radiation.

A liquid lens includes a substrate, an anti-reflection (AR) coating, and a chipless radio frequency identification (RFID) tag. The substrate includes central and peripheral portions. The AR coating is disposed on the substrate. The chipless RFID tag is disposed in the peripheral portion to uniquely identify the liquid lens.

Embodiments of the present disclosure generally relate to a wireless identification tag with varying identity, and system and methods for use thereof. In one implementation, the tag may include at least one transmitter configured to transmit a tag ID. The tag may also include at least one circuit. The at least one circuit may be configured to receive a first trigger at a first time and generate in a quasi-random manner a first decipherable ID uniquely identifying the tag, and cause the at least one transmitter to transmit the first decipherable ID. The at least one circuit may also be configured to receive a second trigger at a second time and generate in a quasi-random manner a second decipherable ID different from the first decipherable ID and uniquely identifying the tag, and cause the at least one transmitter to transmit the second decipherable ID.

Backscatter tags, comprising: antennas; single pole, multiple throw switches each switch (S) having pole terminal connected to one of the antennas, and each having first throw terminal (TT) connected to first side (FS) of inductor (I) for S, second TT connected to FS of capacitor (C) for S, third TT connected to fixed voltage level (FVL), fourth TT that is floating, wherein second side (SS) of I and SS of C are connected to the FVL; power combiner (PC) having inputs connected to fifth TT of each of two of the switches; power detector (PD) having an input connected to output of PC; analog to digital converter (ADC) having input connected to output of PD; hardware processor coupled to output of the ADC and coupled to control terminal of each of the switches.

Embodiments of the present disclosure generally relate to a wireless identification tag configured to harvest ambient energy and transmit an identification signal intermittently, and system and methods for use thereof. In one implementation, the tag may include a transmitter configured to transmit a first signal to a first receiver in a first frequency, and to transmit a second signal to a second receiver in the first frequency. The tag may also include an energy storage component configured for collecting and storing ambient energy and for powering transmission of the transmitter. The tag may also include a circuit configured to monitor energy stored in the energy storage component, and to prevent the transmitter from transmitting the first signal to the first receiver when the energy stored in the energy storage component is insufficient to transmit the second signal to the second receiver.

Embodiments of the present disclosure generally relate to a wireless identification tag triggerable by an EAS gate while remaining invisible to the EAS gate, and system and methods for use thereof. In one implementation, the tag may include an antenna tuned to receive energy transmitted in at least one EAS gate frequency range and configured to be non-detectable by the EAS gate. The tag may also include a transmitter configured to send an identification signal and an energy storage component for powering the transmitter. The tag may also include a circuit connected to the antenna. The circuit may be configured to detect energy transmitted from the EAS gate in at least one of the EAS gate frequency ranges, and to cause the transmitter to transmit, to a receiver other than the EAS gate, the identification signal in a frequency outside the EAS gate frequency ranges.

Embodiments of the present specification provide a target recognition method, apparatus, and system. The method comprises: obtaining an image recognition result and a radio frequency recognition result of target objects in a target region, and then determining the distribution of the target objects in the target region according to the radio frequency recognition result and the image recognition result. Since the radio frequency recognition result and the image recognition result are fused, the target objects in the target region can be accurately recognized, so as to improve the recognition accuracy.

In one example in accordance with the present disclosure, a system is described. The system includes at least one directional antenna to 1) emit energy waves towards a mass in which an object is disposed and 2) receive reflected signals from a resonator disposed on the object as the mass is moved relative to the directional antenna. The system also includes a controller to, based on received reflected signals, determine a pose of the object within the mass.

Embodiments of the present disclosure generally relate to a wireless identification tag with varying ID transmission timing, and system and methods for use thereof. In one implementation, the tag may include at least one transmitter and an energy storage component electrically connected to the at least one transmitter. The energy storage component may be configured to collect and store ambient energy and to power transmission of the at least one transmitter. The tag may also include at least one circuit. The at least one circuit may be configured to cause the at least one transmitter to transmit a sequence of identification signals in non-uniform intervals such that times between identification signal transmissions of three consecutive transmissions vary.

The present invention relates to a chipless RFID tag (T), comprising: —a dielectric substrate (1); and —electromagnetic resonators (3) excitable by an external electromagnetic field and respectively arranged on separate spatial locations of the dielectric substrate (1) forming a row, and configured to resonate at a common resonant frequency. The dielectric substrate (1) defines several predetermined encoding areas that include the separate spatial locations, so that data is encoded by the presence/absence of operative electromagnetic resonators (3) thereon. The present invention also relates to a system comprising the chipless RFID tag of the invention and a RFID reader (R) reading an encoded code by detecting the presence/absence of attenuation peaks on an electromagnetic wave providing the external electromagnetic field to the electromagnetic resonators (3). The present invention also relates to a method for encoding data on a chipless RFID tag defined according to the present invention.