Rfid Reading Apparatus and Method

• US 20090058603A1
• Filed: 06/20/2006
• Published: 03/05/2009
• Est. Priority Date: 07/08/2005
• Status: Abandoned Application

• Current Assignee: Valtion Teknillinen Tutkimuskeskus
• Original Assignee: Valtion Teknillinen Tutkimuskeskus
• Inventors: Kiviranta, Mikko, Seppa, Heikki, Varpula, Timo, Pursula, Pekka
• Application Number:
  US11/988,241
• Publication Number:
  US 20090058603A1
• Time in Patent Office: Days
• US Class Current: 340/10.100
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver

Abstract

This publication discloses an RFDD reading apparatus (1) and a method for the reading apparatus. The RFID reading apparatus comprises a transmitter (3), which is arranged to feed power to at least one RFED tag (2) in the vicinity of the RFID reading apparatus (1), and a receiver (4) operating on the frequency of the transmitter (3), so that the transmitter (3) and the receiver (4) are in operation simultaneously and the receiver (4) is arranged to receiver through a radio channel (7) a reflected signal of at least one RFDD tag (2) in the vicinity of the reading device. In accordance with the invention, the RFDD reading apparatus (1) comprises additionally means (Z2, 12, 13, 14, 20) for separating the payload signal arriving from the RFDD tag (2) from signals other than those arriving from the RFDD tag (2).

Claims

1. RFID reading apparatus (1), which comprises

a transmitter (3), which is arranged to feed power to at least one RFID tag (2) in the vicinity of the RFID reading apparatus (1), and

a receiver (4) operating on the frequency of the transmitter (3), so that the transmitter (3) and the receiver (4) are generally in operation simultaneously and the receiver (4) is arranged to receive through a radio channel (7) a reflected signal of at least one RFID tag (2) in the vicinity of the reading device,

characterized in that, the RFID reading apparatus (1) comprises in addition

means (Z₂, 12, 13, 14, 20) for separating the payload signal arriving from the RFID tag (2) from signals other than those arriving from the RFID tag (2).

2. RFID reading apparatus (1) according to claim 1, characterized in that it comprises an artificial load or reference impedance (14, Z₂) for separating the payload signal arriving from the RFID tag (2) from signals other than those arriving from the RFID tag (2).

3. RFID reading apparatus (1) according to claim 2, characterized in that the artificial load or reference impedance (14, Z₂) is adjustable.

4. RFID reading apparatus (1) according to claim 3, characterized in that the apparatus comprises means (12) for adjusting the artificial load or reference impedance (14, Z₂) during operation.

5. RFID reading apparatus (1) according to claim 1, 2, 3, or 4, characterized in that the artificial load or reference impedance (14, Z₂) is located to be part of a bridge coupling.

6. RFID reading apparatus (1) according to claim 1, characterized in that the receiver is coupled to separate the payload signal arriving from the RFID tag (2) from signals other than those arriving from the RFID tag (2).

7. RFID reading apparatus (1) according to claim 6, characterized in that the correction signal is adjustable.

8. RFID reading apparatus (1) according to claim 6, characterized in that the apparatus comprises means (12) for regulating the correction signal.

9. RFID reading method, in which method

to an RFID tag (2) is fed power over a radio link (7) in order to create operating energy for the RFID tag (2) and for creating reception for the return reflection signal,

the signal reflected by the RFID tag (2) is received and detected,

characterized in that

signals other than those reflected by the RFID tag (2) are defined and attenuated in order to separate the returning payload signal from the RFID tag (2) from other signals.

10. RFID reading method according to claim 9, characterized in that an artificial load or reference impedance (14, Z₂) is used in order to separate the payload signal arriving from the RFID tag (2) from signals other than those arriving from the RFID tag (2).

11. RFID reading method according to claim 10, characterized in that the artificial load or reference impedance (14, Z₂) are regulated during operation.

12. RFID reading method according to claim 9, 10, or 11, characterized in that the artificial load or reference impedance (14, Z₂) is situated as part of the bridge coupling.

13. RFID reading method according to claim 9, characterized in that a correction signal is used in the receiver, in order to separate the payload signal arriving from the RFID tag (2) form signals other than those arriving from the RFID tag (2).

14. RFID reading method according to claim 13, characterized in that the correction signal is regulated during operation.