Rfid Reader and Rfid System

• US 20080278329A1
• Filed: 11/03/2006
• Published: 11/13/2008
• Est. Priority Date: 11/03/2005
• Status: Active Grant

• Current Assignee: ATEC AP Co., Ltd. (ATEC T& Co., Ltd.)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Cho, Young Bin, Choi, Jae Yeon, Lee, Yong Hee, Kim, Nam Yun
• Granted Patent: US 8,154,386 B2
• Time in Patent Office: Days
• US Class Current: 340/572.4
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 7/0602 using antenna switching H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence

Abstract

Provided are an RF reader and an RF system. The RF reader includes: a plurality of antennas; a path selector for selecting a transmit or receive path of an RF signal; an RF processor for processing the RF signal received through the transmit or receive path of the path selector; and a controller for controlling the path selector selecting a path.

Claims

1. A radio frequency identification reader comprising:

a plurality of antennas for transmitting/receiving a radio frequency signal;

a path selector for selecting a transmit or receive path of the radio frequency signal;

a radio frequency processor for processing the radio frequency signal sent to the transmit path or receive path of the path selector; and

a controller for controlling a path selection of the path selector.

2. The radio frequency identification reader according to claim 1, wherein the plurality of antennas communicate with one or more of the electronic tags by transmitting or receiving the radio frequency signal.

3. The radio frequency identification reader according to claim 1, wherein the plurality of antennas comprise:

first and second antennas for transmitting or receiving the radio frequency signal at one side of moving range of the electronic tag; and

third and fourth antennas for transmitting or receiving the radio frequency signal at the other side of moving range of the electronic tag.

4. The radio frequency identification reader according to claim 1, wherein the path selector comprises:

a first switch connected to the plurality of antennas in order; and

a second switch connected to the first switch for selecting the transmit or receive path of the radio frequency signal.

5. The radio frequency identification reader according to claim 4, wherein the path selector comprises a third switch connecting a signal inputted through the second switch according a transmit or receive mode to a ground or a receive path.

6. The radio frequency identification reader according to claim 4, wherein the switch is a semiconductor switch.

7. The radio frequency identification reader according to claim 1, wherein the radio frequency processor comprises:

a radio frequency receiver for squelching a noise of the radio frequency signal received through the path selector, amplifying the radio frequency signal, and demodulating the amplified signal; and

a radio frequency transmitter for modulating the transmitted radio frequency signal and outputting the radio frequency signal to the path selector.

8. The radio frequency identification reader according to claim 1, wherein the radio frequency identification reader comprises a baseband processor for converting the received radio frequency signal at the radio frequency processor into digital data, sending the digital data to the controller, and converting the digital data into an analog signal.

9. The radio frequency identification reader according to claim 7, wherein the radio frequency transmitter operates selectively based on one of the modulation types such as DSB-ASK, SSB-ASK and PR-ASK which are encoded.

10. The radio frequency identification reader according to claim 7, wherein the radio frequency transmitter uses a modulation format of one of an Electronic Product Code Class 1 and ISO 18000-6 UHF radio frequency identification protocol.

11. The radio frequency identification reader according to claim 7, wherein the radio frequency transmitter comprises:

a phase locked loop section generating the radio frequency signal;

a phase shifter changing the input radio frequency signal into a first and second radio frequency signals with a first and second phases and modulating the radio frequency signals according to data; and

a signal selector selectively outputting the first and second radio frequency signal modulated by the phase shifter.

12. The radio frequency identification reader according to claim 11, wherein the phase shifter for adjusting the first and second radio frequency signals with 180 degree phase differential between the first and second phases of the two radio frequency signals.

13. The radio frequency identification reader according to claim 11, wherein a pulse width of the radio frequency signal outputted by the phase shifter and the signal selector has a value of 0.265 to 0.525 Tari.

14. The radio frequency identification reader according to claim 7, wherein the radio frequency processor is a communication by using a Tari value from 6.25 to 25 us.

15. The radio frequency identification reader according to claim 11, wherein the pulse width is measured at a point of 50% on the pulse.

16. A radio frequency identification reader comprising:

a phase shifter changing an input radio frequency signal into a first and second radio frequency signals with a first and second phases and modulating the radio frequency signals according to data;

a signal selector for selecting the first or second radio frequency signal according to a modulation type; and

a controller for controlling a signal output path and period of the phase shifter and signal selector.

17. The radio frequency identification reader according to claim 16, wherein the controller operates selectively based on one of the modulation types such as DSB-ASK, SSB-ASK and PR-ASK.

18. The radio frequency identification reader according to claim 16, wherein the phase shifter for adjusting the first and second radio frequency signals with 180 degree phase differential between the first and second phases of the two radio frequency signals.

19. The radio frequency identification system comprising:

one or more of passive electronic tags; and

an radio frequency identification reader having a plurality of antennas and communicating with the electronic tag by different modulation types according to coding formats.

20. The radio frequency identification system according to claim 19, wherein the radio frequency identification reader comprises a path selector for selectively outputting a transmit or receive path of a radio frequency signal.

21. The radio frequency identification system according to claim 19, wherein the radio frequency identification reader comprises a radio frequency transmitter for outputting a radio frequency signal modulated selectively by one of the modulation types such as DSB-ASK, SSB-ASK and PR-ASK.