A presence detection system (100) including: an RFID interrogator (102); and a plurality of passive RFID tags (11 to MN), the RFID interrogator (102) is configured to: measure a received signal strength indicator (RSSI) level from each of the plurality of passive RFID tags (11 to MN); compare a measured RSSI level to a reference RSSI level for each of the plurality of passive RFID tags (11 to MN); and determine whether a difference between the measured RSSI level and the reference RSSI level is greater than a threshold value.

A radio frequency identification (RFID) tag includes an antenna, an analog front end, a processing circuit, and memory. The analog front end includes a power circuit, a tuning circuit, a transmitter, and a receiver. The power circuit is operably coupled to convert a radio frequency (RF) signal into a power supply voltage. The tuning circuit, when enabled, adjusts an RF characteristic of the analog front end to tune power harvesting from the RF signal. The transmitter is operably coupled to transmit a response signal to the RFID reader via the antenna. The receiver is operably coupled to receive a command signal from the RFID reader, wherein the command signal is contained within a portion of the RF signal. The processing circuit is operable to interpret the command signal and generate the response signal.

An operation of calibrating the object using a reference reader is performed, the calibration operation including an operation of placing the reference reader at various distances away from the object that correspond to various values of a parameter within the object that is representative of the intensity of the signal received by the object, and, for each distance, an operation of determining an internal phase-shift compensation in the object with respect to a nominal internal phase shift, making it possible to obtain a load modulation amplitude that is higher, in terms of absolute value, than a threshold, and an operation of storing a lookup table of the various values of the parameter and the corresponding internal phase-shift compensations.

A wireless tag processing device includes a wireless tag reader-writer and a processor configured to acquire first and second sets of parameter values, control the reader-writer to transmit a radio wave using each parameter value of the first set and acquire a first intensity of a response wave from a wireless tag, when a highest first intensity satisfies a first condition, determine a parameter value of the first set corresponding to the highest intensity as a parameter value to be used by the reader-writer, and when the highest intensity does not satisfy the condition, control the reader-writer to transmit a radio wave using each parameter value of the second set and acquire a second intensity, and when a highest second intensity satisfies a second condition, determine a parameter value of the second set corresponding to the highest second intensity as the parameter value to be used by the reader-writer.

Provided are an RFID tag information reading apparatus and method, including a signal management circuit, configured to output an operation frequency signal; a resonant circuit, configured to receive the operation frequency signal, adjust a capacitance value and an inductance value of the resonant circuit according to the operation frequency signal, so that the resonant circuit generates a resonance for generating a sine wave signal at a frequency point of the operation frequency signal, the resonant circuit is further configured to generate an electromagnetic wave from the sine wave signal, radiate the electromagnetic wave to a tag, and trigger the tag to return a tag identity signal; and a decoding identification circuit, configured to identify tag information according to the tag identity signal returned by the tag; where the signal management circuit is connected with the resonant circuit, and the resonant circuit is connected with the decoding identification circuit.

There is provided a method of detecting the temperature of a component of a support system for semiconductor processing equipment, the method comprising: applying a radio frequency identity tag to the component, the radio frequency identity tag having a serial number; reading the radio frequency identity tag with a reader, the reader arranged to read the serial number of the radio frequency identity tag, and to identify the resonant frequency of the radio frequency identity tag; and converting the resonant frequency of the radio frequency tag to a temperature of the radio frequency identity tag.

Provided are an RFID tag information reading apparatus and method, including a signal management circuit, configured to output an operation frequency signal; a resonant circuit, configured to receive the operation frequency signal, adjust a capacitance value and an inductance value of the resonant circuit according to the operation frequency signal, so that the resonant circuit generates a resonance for generating a sine wave signal at a frequency point of the operation frequency signal, the resonant circuit is further configured to generate an electromagnetic wave from the sine wave signal, radiate the electromagnetic wave to a tag, and trigger the tag to return a tag identity signal; and a decoding identification circuit, configured to identify tag information according to the tag identity signal returned by the tag; where the signal management circuit is connected with the resonant circuit, and the resonant circuit is connected with the decoding identification circuit.

Systems and methods for operating a tag system. The methods comprising: emitting a wireless signal from an antenna of the tag with a first signal characteristic when the tag is proximate to an active antenna modulation marker; changing an impedance of a sensor from a first impedance value to a second impedance value when the active antenna modulation marker is exposed to a stimulus; and emitting a wireless signal from the antenna of the tag with a second signal characteristic when the tag is proximate to the active antenna modulation marker and the sensor has the second impedance value.

A method for detecting receivers includes a step of detecting a receiver, in which step a general controller detects an adjustable receiver when a general antenna receives a secondary wave emitted by the adjustable receiver, followed by a reconfiguration step in which the general controller commands a controller of the detected adjustable receiver to switch to an interaction mode in which the impedance of the adjustable receiver is alternated between a first configuration impedance and a second configuration impedance in order to detect other receivers. The reconfiguration step is of a duration that is an order of magnitude higher than the duration of each alternation of the first and second configuration impedances.

Systems and methods for operating a tag system. The methods comprising: emitting a wireless signal from an antenna of the tag with a first signal characteristic when the tag is proximate to an active antenna modulation marker; changing an impedance of a sensor from a first impedance value to a second impedance value when the active antenna modulation marker is exposed to a stimulus; and emitting a wireless signal from the antenna of the tag with a second signal characteristic when the tag is proximate to the active antenna modulation marker and the sensor has the second impedance value.