| 摘要 |
A tag collision preventing method in a wireless frequency identification system is provided to determine all the tags in an RF field, efficiently and rapidly by utilizing advantages of an existing binary tree protocol and query tree protocol and adopting a new collision preventing protocol. A tag collision preventing method in a wireless frequency identification system comprises the following several steps. A reader sends a start signal via plural tags in a standby state(S1), converts a current mode of each tag into a listening mode(S2), and transmits data by each tag. A current mode of the tag, which is the same as the data transmitted by the reader, is converted into a sending mode(S3) and a current mode of the tag, which is different from the data transmitted by the reader, is converted into the standby mode. If a stop signal is transmitted by the reader and the data sent by the tag is not the final bit, a current mode of the tag is converted into the listening mode again and the tag prepares for receipt of new data. If the stop signal is not transmitted by the reader, the tag sends the next bit of the bit previously sent, and if the bit sent by the tag is the final bit, a current mode of the tag is converted into a killed mode(S4).
|
