A first element and a second element of a same device communicate with each other. The first element sends the second element a first piece of information representative of energy supplied by an electromagnetic field supplying power the device. The second element adapts its operating frequency as a function of the first piece of information.

A Radio Frequency Identification (RFID) tag is disclosed. The RFID tag includes an antenna port to receive an input AC signal and a hybrid limiter including a clamping device configured to limit a voltage of the input AC signal to a preconfigured limit. The hybrid limiter is configured to provide a stable ground reference for the clamping device.

A sheet processing apparatus for processing sheets each with a wireless tag, includes a roller, a wireless tag reader/writer, and a controller configured to control the roller to convey a first sheet with a first tag along a path, control the reader/writer to acquire first strengths of radio signals received from the first tag during the conveyance and second strengths of radio signals received from wireless tags of sheets not being conveyed, determine a threshold value of signal strength for distinguishing a wireless tag being conveyed from wireless tags not being conveyed based on the first and second strengths, and control the roller to convey a second sheet with a second tag and control the reader/writer to write to the second tag when a strength of a radio signal from the second tag is greater than or equal to the threshold value.

An circuit includes a first inductive coil and a second inductive coil each including a plurality of metal traces. The first and second inductive coils are each configured to receive a first signal from an electromagnetic field and generate respective first and second output voltages. Each of the first inductive coil and the second inductive coil are configured to inductively couple to the electromagnetic field. A first circuit element is configured to receive the first output voltage and generate a first response at a first power level of the first output voltage. A second circuit element is configured to receive the second output voltage and transition to an active state to perform one or more functions when the second output voltage exceeds a second power level. The first and second power levels are related to movement of the first and second inductive coils through the electromagnetic field.

Systems and methods for operating an Electronic Smart Tag (“EST”). The methods involve: operating the EST in a first operational state in which first item related information is output from an electronic output device of the EST that is powered by an energy storage device storing energy harvested from an external energy source; detecting when a charge level of the energy storage device reaches or falls below a first threshold level; and transitioning an operational state of the EST from the first operational state to a second operation state in which a message is output from EST requesting that a mobile device be placed in proximity to the EST for purposes of obtaining at least a first portion of the first item related information, in response to the detection that the charge level of the energy storage device has reached or fallen below the first threshold level.

A device comprising: an antenna; a power harvesting circuit for harvesting power from a radio frequency field received at the antenna in order to power functions of the device; a communication unit coupled to the antenna for transmitting and receiving signals by means of the antenna, the communication device being configured to communicate according to a protocol in which a party to a communication session deems the session to have timed out if during a predetermined period it does not receive a signal from another party to the session; and a module comprising a processing circuit; the device being configured to interrupt the operation of the module when the communication unit is transmitting a signal by means of the antenna.

In accordance with a first aspect of the present disclosure, a radio frequency identification (RFID) device is provided, comprising a first power domain, a second power domain, a first processing unit, and a second processing unit, wherein the first processing unit is configured to execute one or more first operations and the second processing unit is configured to execute one or more second operations, wherein the first operations output intermediate data which are used as input for the second operations, and wherein the first processing unit is configured to operate in the first power domain and the second processing unit is configured to operate in the second power domain, said first power domain having a larger amount of available power than the second power domain. In accordance with further aspects of the present disclosure, a corresponding method of operating a radio frequency identification (RFID) device is conceived, and a corresponding computer program is provided.

In a management system of a game token coin, one RFID tag having a data non-rewritable region and a data rewritable region is imparted to the game token coin. The location relating information of the game token coin is stored in the data rewritable region. The system includes a writer configured to additionally write the location relating information, a reader configured to read the location relating information from a plurality of the game token coins, and a management controller configure to examine the information obtained from the reader. The management controller includes a function that determines whether a history of the location relating information obtained from the reader has no abnormality.

An image forming apparatus includes a storage unit storing sheets each including a wireless tag, a printer, a communication device, and a controller for controlling the printer to convey a first sheet, acquiring first strengths of signals from a first tag on a first sheet during the conveyance of the first sheet and second strengths from tags not sheets being conveyed. Based on the acquired strengths, the controller determines a threshold value for distinguishing between sheets being conveyed and not being conveyed. The controller then controls the communication device to write information to a tag on a sheet being conveyed based on the threshold value.

In accordance with a first aspect of the present disclosure, a transponder is provided, comprising: a field strength range determination unit configured to determine a field strength range of a radio frequency (RF) field generated by an external reader device; a controller configured to delay processing of a command by the transponder in dependence on the field strength range determined by the field strength range determination unit. In accordance with further aspects of the present disclosure, a corresponding method of operating a transponder is conceived, and a corresponding computer program is provided.