USER'S MANUAL, VERSION 2.0
Copyright © Convergence Systems Limited 2021, All Rights Reserved
339
Appendix E: Query Algorithm
There are 2 types of Query Algorithm: Fixed Q and Dynamic Q.
For Fixed Q, the Q value does not change. In other words, the expected Tag Population does
not change.
For Dynamic Q, the Q value changes adaptively: when there are a lot of inventory repeats
where no tags respond, the reader will interpret that there are not that many RFID tags in the
front environment, and hence it is more efficient to change the Q to a smaller value. When
there are a lot of inventory repeats where the reader receives data but they do not satisfy
checksum, meaning there is heavy collision, then the reader will interpret that there are too
many RFID tags in the environment and hence it is better to increase the value of Q.
Dynamic Q algorithm is a way to allow the RFID reader to adapt to different amount of RFID
tags being seen by the reader. The idea is that if there are a smaller number of tags in the
environment, then the Q can be reduced and the reader can collect all the tag data faster.