Near Field Radio Frequency Communication System

• US 20100245054A1
• Filed: 11/21/2008
• Published: 09/30/2010
• Est. Priority Date: 11/21/2007
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Kim, Nam Yun
• Granted Patent: US 8,947,210 B2
• Time in Patent Office: Days
• US Class Current: 340/10.400
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 7/0604 with predefined switching scheme

Abstract

Disclosed is a near field radio frequency communication system. The near field radio frequency communication system comprising: a master RFID/USN device which comprises a plurality of antennas to sequentially shower an energy signal through the antennas; and a slave RFID/USN device which generates a first power using the energy signal, detects a power level of the first power, and transmits a information created based on the power level to the master RFID/USN device, wherein the master RFID/USN device creates a first position information of the slave RFID/USN device related to a direction by determining an antenna used to communicate with the slave RFID/USN device, and a second position information of the slave RFID/USN device related to a distance using the information created based on the power level.

Claims

1. A near field radio frequency communication system comprising:

a master RFID/USN device which comprises a plurality of antennas to sequentially shower an energy signal through the antennas; and

a slave RFID/USN device which generates a first power using the energy signal, detects a power level of the first power, and transmits a information created based on the power level to the master RFID/USN device,

wherein the master RFID/USN device creates a first position information of the slave RFID/USN device related to a direction by determining an antenna used to communicate with the slave RFID/USN device, and a second position information of the slave RFID/USN device related to a distance using the information created based on the power level.

2. The near field radio frequency communication system of claim 1, wherein the slave RFID/USN device operates in a wake-up mode by driving a power supply to transmit a tag identification information and a tag information if the power level of the first power exceeds a reference value, and operates in a sleep mode to transmit a waiting state information if the power level of the first power is less than or equal to the reference value.

3. The near field radio frequency communication system of claim 2, wherein the master RFID/USN device creates the second position information representing that the slave RFID/USN device is positioned in a coverage area if the tag identification information and the tag information are received, and creates the second position information representing that the slave RFID/USN device is positioned outside the coverage area if the waiting state information is received.

4. The near field radio frequency communication system of claim 1, comprising a management computer which creates a tag position information by receiving the first and second position information from the master RFID/USN device, stores the tag position information in a database by statistically processing the tag position information, and transmits the tag identification information and the tag position information to other master RFID/USN device.

5. The near field radio frequency communication system of claim 4, wherein a plurality of the master RFID/USN devices are provided, and

the management computer creates a reader coordinate information based on positions of the master RFID/USN devices, and creates a tag coordinate information by matching a position of the slave RFID/USN device, which communicates with the master RFID/USN device, with the reader coordinate information.

6. The near field radio frequency communication system of claim 1, wherein the master RFID/USN device transmits the first and second position information and a tag identification information to other master RFID/USN device such that the other master RFID/USN device communicates with the slave RFID/USN device.

7. The near field radio frequency communication system of claim 1, wherein the master RFID/USN device transmits a wake-up selection information to the slave RFID/USN device, the wake-up selection information being used to activate an operation of the slave RFID/USN device, and

the slave RFID/USN device stores the wake-up selection information in a memory if the wake-up selection information is first received.

8. The near field radio frequency communication system of claim 1, wherein the slave RFID/USN device comprises:

a memory which stores a first wake-up selection information;

a second controller which operates in a wake-up mode according to the first wake-up selection information to process a communication protocol; and

a mode controller which operates by the first power, and compares a second wake-up selection information received from the master RFID/USN device with the first wake-up selection information stored in the memory to operate a power supply if the second wake-up selection information is identical to the first wake-up selection information, thereby transmitting the second wake-up selection information to the second controller.

9. The near field radio frequency communication system of claim 8, wherein the slave RFID/USN device creates a first response code reporting that the first wake-up selection information is successfully received and stored in the memory, and transmits the first response code to the master RFID/USN device.

10. The near field radio frequency communication system of claim 9, wherein the slave RFID/USN device creates a second response code reporting that the second wake-up selection information is received, and the slave RFID/USN device operates in the wake-up mode to transmit the second response code to the master RFID/USN device, and

the master RFID/USN device transmits an information request signal to the slave RFID/USN device to make RFID communication if the second response code is received.

11. The near field radio frequency communication system of claim 8, wherein master RFID/USN device transmits the second wake-up selection information together with the energy signal, and

the slave RFID/USN device comprises a voltage oscillator which creates the first power based on the energy signal and delivers the first power to the mode controller.

12. The near field radio frequency communication system of claim 1, wherein the master RFID/USN device comprises:

a plurality of antennas;

a first phase lock loop circuit which generates an oscillation signal;

a first receive signal processing unit which processes a receive signal by using the oscillation signal;

a first transmit signal processing unit which processes a transmit signal by using the oscillation signal;

an RF radiation unit which generates the energy signal by using the oscillation signal;

a first signal splitter which switches the antennas; and

a second signal splitter which switches the first signal splitter to one of the first receive signal processing unit, the first transmit signal processing unit, and the RF radiation unit.

13. The near field radio frequency communication system of claim 1, wherein the slave RFID/USN device comprises:

a third signal splitter for branching signal paths of the antennas;

a second receive signal processing unit electrically connected to the third signal splitter to process a receive signal;

a second transmit signal processing unit electrically connected to the third signal splitter to process a transmit signal;

a voltage oscillator electrically connected to the third signal splitter to convert the energy signal to the first power;

a signal measuring unit which detects the power level of the first power; and

a second controller which creates the information according to the detected power level of the signal measuring unit.

14. The near field radio frequency communication system of claim 1, wherein the master RFID/USN device is realized by using a full function device (FFD) ZigBee module or a personal area network (PAN) coordinator ZigBee module, and

the slave RFID/USN device is realized by using a reduced function device (RFD) ZigBee module.

15. The near field radio frequency communication system of claim 1, wherein the master RFID/USN device comprises at least one of an RFID/USN reader, a router, and a coordinator, and

the slave RFID/USN device comprises at least one of an RFID tag and a sensor node.