To provide a wireless tag operating when the need arises while reducing power consumption according to a situation of a reader, a setter, an interrogator, presence/absence of another wireless tag or the like.
With a transmission function and a reception function of this wireless tag 10a stopped, when a loaded sensor 11 senses vibration, an illuminance or the like to start, a transmission part 12 transmits a synchronization requirement signal to the reader 20 by the transmission function, and the reception function of a reception part 13 comes into a reception signal waiting state. When the reader 20 receives the synchronization requirement signal, the reader 20 sends back information related to synchronization of a wireless signal transmitted from the wireless tag 10a on and after it as a synchronous relation information response. When the reception part 13 of the wireless tag 10a receives the synchronous relation information response, the synchronization is established between the wireless tag 10a and the reader 20 according to synchronous relation information thereof, and the transmission part 12 performs normal data transmission to the reader 20.
COPYRIGHT: (C)2007,JPO&INPIT
Hiroshi Nakata
Hideyuki Tsuboi
Toshimitsu Tsubaki
Masashi Shimizu
| JP2005316724A | ||||
| JP62291224A | ||||
| JP7131404A | ||||
| JP2005249566A | ||||
| JP2006048630A |
Yasuhiko Murayama