Reader/writer and RFID system

• US 20060077039A1
• Filed: 01/26/2005
• Published: 04/13/2006
• Est. Priority Date: 09/30/2004
• Status: Abandoned Application

• Current Assignee: Fujitsu Frontech Limited (Fujitsu Limited), Fujitsu Limited
• Original Assignee: Fujitsu Frontech Limited (Fujitsu Limited), Fujitsu Limited
• Inventors: Sugimura, Yoshiyasu, Ono, Takashi, Miyazawa, Hideo, Hashimoto, Shigeru, Ibi, Toshiaki
• Application Number:
  US11/042,543
• Publication Number:
  US 20060077039A1
• Time in Patent Office: Days
• US Class Current: 340/10.100
• CPC Class Codes: G06K 7/10069 the collision being resolved in the frequency domain, e.g. by hopping from one frequency to the other frequency hopping or spread spectrum techniques H04B7/00
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
• CPC Class Codes: G06K 7/10435 the interrogation device being positioned close to a conveyor belt or the like on which moving record carriers are passing conveying in accordance with bodily destination marks, see B65G47/46, sorting of objects carrying identity markings, see B07C5/34
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00

Abstract

A reader/writer includes two antennas that perform reading/writing of information from/to wireless tags that are moving. The antennas are positioned in such a manner that their communication ranges have an overlap along a route in which the wireless tag moves.

Claims

1. A reader/writer for a wireless tag that moves, comprising:

a plurality of antennas that receive a read signal from the wireless tag and transmit a write signal to the wireless tag, each antenna having a communication range, the antennas being positioned in such a manner that a communication range of any one of the antennas overlaps with a communication range of adjacent antenna along a route in which the wireless tag moves; and

a signal processing unit that divides the write signal into a plurality of divisional write-signals, each divisional write-signal corresponding to each of the antennas, and combines the read signals which are received by the antennas into a combined read-signal.

2. A reader/writer for a wireless tag that moves, comprising:

an antenna that receives a read signal from the wireless tag and that transmits a write signal to the wireless tag, the antenna having a communication range; and

a controlling unit that controls an orientation of the antenna in such a manner that the wireless tag is in the communication range.

3. An RFID system for a plurality of wireless tags that move, comprising:

a first reader/writer that includes a sequence information generating unit which receives identification information from each of the wireless tags and, based on the identification information, generates sequence information that represents a sequence in which the wireless tags move, and

a second reader/writer that includes a communication unit which reads and writes information from and to the wireless tags based on the sequence information.

4. The RFID system according to claim 3, wherein the sequence information generating unit generates the sequence information in accordance with a sequence in which the wireless tags move out of a communication range of the first reader/writer, or a sequence in which the wireless tags enter into the communication range.

5. The RFID system according to claim 3, wherein the communication range of the first reader/writer is narrower than a communication range of the second reader/writer.

6. The RFID system according to claim 3, further comprising a plurality of the second reader/writers, and the sequence information generating unit generates sequence information corresponding to each of the second reader/writer.

7. An RFID system for a plurality of wireless tags that move, comprising:

a plurality of reader/writers that receive wireless tag identification information from the wireless tags and write and read information to and from the wireless tags based on the identification information, the reader/writers being positioned with an intervening space therebetween, wherein the space is calculated based on a speed of movement of the wireless tags, a distance between adjacent wireless tags, and a communication range of each reader/writer.