摘要:
A process is disclosed for exchanging data between one or more RFID tags and an interrogation unit comprising transmitting a burst of data from the one or more RFID tags.
摘要:
A process is disclosed for communicating with individual tags in a population of tags having a binary tree organization, wherein each tag corresponds to a leaf node of the binary tree. The process includes singulating a predetermined leaf node and returning to a designated re-entry node associated with the predetermined leaf node after singulating.
摘要:
A radio frequency identification tag is disclosed that is configured to transmit a signal modulated with one of more than two different subcarrier modulation frequencies such that the signal represents more than one binary bit as a single symbol.
摘要:
RFID system components, such as readers and tags, communicate by a reader transmitting waveforms that encode a calibration symbol and a divide ratio. Tags include a processor to determine a backscatter link period result by dividing a count value representing the calibration symbol by the divide ratio and adding an adjustment. Tags modulate a backscatter waveform that includes symbols using a link period determined from the result.
摘要:
RFID tags, tag circuits, and methods adapting the reception bandwidth. A tag has a decoder for decoding a first received wireless signal subject to a reception bandwidth setting. The tag also has a selector switch for transitioning to a different setting, such as by switching to using a different filter. A subsequently received second signal is decoded subject to the new reception bandwidth setting.
摘要:
RFID system components, such as readers and tags, communicate by a reader transmitting waveforms that encode a calibration symbol and a divide ratio. Tags include a processor to determine a backscatter link period result by dividing a count value representing the calibration symbol by the divide ratio and adding an adjustment. Tags modulate a backscatter waveform that includes symbols using a link period determined from the result.
摘要:
RFID system components, such as readers and tags, communicate by a reader transmitting waveforms that encode a calibration symbol and a divide ratio. Tags include a processor to determine a backscatter link period result by dividing a count value representing the calibration symbol by the divide ratio and adding an adjustment. Tags modulate a backscatter waveform that includes symbols using a link period determined from the result.
摘要:
RFID tags are commanded to generate a pilot tone in their backscatter. When the backscattered pilot tone is received in the reader, the pilot tone is used to estimate the tag period/frequency. Then, the estimate is used to seed and lock a symbol timing recovery loop, which provides a detected signal to one or more correlators for detecting the tag preamble. A delayed version of the received tag signal is compared against a baseline signal threshold established from the received signal to detect the pilot tone.
摘要:
Systems, software, devices, and methods are described for an RFID reader system to communicate with RFID tags. RF energy detected in conjunction with using a selected channel is detected and used to adjust a waveform shaping parameter. The waveform shaping parameter can be additionally stored, and then reconstructed for later use in the same channel. Reconstruction can optionally be also from derived channel performance data. RF waves can be transmitted from the reader to the RFID tags and RF waves can be backscattered from the RFID tags. At least some of the RF waves transmitted to or backscattered from the RFID tags have a waveform with a shape according to the reconstructed waveform shaping parameter.
摘要:
An RFID reader comprising an antenna, a memory adapted to store a plurality of code modules, a selector for selecting one of the code modules, and a modulator adapted to operate the antenna in accordance with the selected code module.