Impinj, Inc.

Amir Sarajedini

Christopher J Diorio

Scott A Cooper

Kurt Eugene Sundstrom

John D Hyde

Todd E Humes

Aanand Esterberg

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.

RFID reader systems detecting pilot tone

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.

Adaptable bandwidth RFID tags

Growing community of inventors

Aliso Viejo, CA, United States of America

Amir Sarajedini