Provided is a method for encoding chipless RFID tags in real-time. The method includes exposing a chipless RFID transponder to a conductive material, the RFID transponder comprising an antenna and a plurality of resonant structures, the plurality of resonant structures together defining a first spectral signature. Each of the plurality of resonant structures includes a respective one of a frequency domain. The method also includes depositing a conductive material on at least one of the resonant structures to short the at least one of the resonant structures. The remainder of the plurality of resonant structures that are not shorted by the conductive material define a second spectral signature for the RFID transponder.

A radio frequency identification (RFID) tag and reader system including an array of circular resonators with interdigitated capacitor fingers wherein the fingers of each pair are radially aligned and bars disposed between the resonators to reduce coupling between adjacent resonators, wherein subsets of the resonators resonate at respective different resonant frequencies, and the resonators of each of the subsets have the same resonant frequency; and the radio frequency response produced by the tag at a resonant frequency varies depending on the activation of resonators of the subset corresponding to the resonant frequency.

An apparatus that identifies an object includes a frequency detector (112) that detects a frequency over which an RFID tag (102) communicates, and an object identifier (120) that identifies the object based at least in part upon the detected frequency. The frequency detector may detect a plurality of frequencies over which a plurality of RFID tags transmit information. The apparatus also optionally includes a frequency pattern generator that generates a frequency pattern that is indicative of an identity of the object, wherein the object identifier compares the generated frequency pattern with known frequency patterns to determine the identity of the object.

A computer-implemented method for digitization of papercraft folding for creation of a papercraft model may include monitoring, via an RFID reader, a sheet provided with an array of RFID tags. Based on the RFID reader output, the occurrence of a fold performed on the sheet is determined. The method further includes determining fold properties of the occurred fold and storing the fold properties as a fold dataset of the occurred fold.

A detecting system includes: a sensor (10) that includes an antenna unit (11) formed with a metal pattern, and a back surface reflector (13) that faces the antenna unit (11) via an isolation layer (12); and a reader (20) that transmits electromagnetic waves (Fa) to the sensor (10), receives reflected waves (Fr) from the sensor (10), and compares the reflection characteristics of the sensor (10) detected from the reflected waves (Fr) with the reflection characteristics of the sensor (10) stored in advance, to detect a state change in the sensor (10).

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.

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 passive identification tag includes a non-conductive substrate and a resonant structure disposed on the non-conductive substrate the resonant structure is configured to generate a baseline response from a detection signal incident thereon. A characteristic layer disposed on the substrate to modify at least one of an amplitude, phase, group delay, and phase delay of the baseline response to generate a tag response.

A disclosed component may include at least one split-ring resonator, which may be embedded within a material. The split ring resonator may be formed from a three-dimensional (3D) monolithic carbonaceous growth and may detect an electromagnetic ping emitted from a user device. The split ring resonator may generate an electromagnetic return signal in response to the electromagnetic ping. The electromagnetic return signal may indicate a state of the material in a position proximate to a respective split ring resonator. In some aspects, the split-ring resonator may resonate at a first frequency in response to the electromagnetic ping when the material is in a first state, and may resonate at a second frequency in response to the electromagnetic ping when the material is in a second state. A resonant frequency of the 3D monolithic carbonaceous growth may be based on physical characteristics of the material.

Embodiments of the present disclosure generally relate to a wireless identification tag for association with a product to enable product self-identification and system and methods for use thereof. In one implementation, the tag may include at least one antenna tuned to receive energy transmitted at one or more frequencies within certain frequency bands. The tag may also include at least one transmitter that may be configured to send at least one identification signal. The tag may also include at least one circuit. The at least one circuit may be configured to detect whether energy is received in a certain frequency band, and to cause the at least one transmitter to operate in a mode corresponding to the certain frequency band.