| US 7,450,009 B2 | ||
| Wireless tag reader, wireless tag system, computer readable medium and wireless communication method | ||
| Yusuke Doi, Yokohama (Japan); Satoshi Ozaki, Kawasaki (Japan); Shirou Wakayama, Kawasaki (Japan); Masahiro Ishiyama, Kawasaki (Japan); and Toshiyuki Umeda, Tokyo (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Mar. 17, 2006, as Appl. No. 11/377,256. | ||
| Claims priority of application No. 2005-081605 (JP), filed on Mar. 22, 2005. | ||
| Prior Publication US 2006/0220790 A1, Oct. 05, 2006 | ||
| Int. Cl. G08B 13/14 (2006.01) | ||
| U.S. Cl. 340—572.1 | 19 Claims |
| 1. A wireless tag reader communicating with a plurality of wireless tags each of which retains tag information piece and a
bloom filter generated from the tag information piece on the basis of a bloom filter algorithm, the wireless tag reader comprising:
a transmitter configured to transmit a read request signal simultaneously to the wireless tags to request the wireless tags
to read out the bloom filters;
a receiver configured to receive bloom filter signals simultaneously from the wireless tags to acquire a colliding bloom filter
signal;
a decoder configured to decode the colliding bloom filter signal to acquire a composite bloom filter which is equivalent to
logic operation OR on the bloom filters;
a data storage configured to store tag information pieces; and
a filter verifier configured to verify each of tag information pieces in the data storage with the composite bloom filter
to detect tag information pieces for which a verification result is positive or negative.
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