Method for reading ultrahigh frequency RFID tags

Abstract

A method for reading ultrahigh frequency RFID (Radio Frequency Identification) tags is provided, wherein: an ultrahigh frequency RFID scanning system includes an ultrahigh frequency RFID reader and an antenna group; antennas are distributed around a scanned object; the RFID tags are in the scanned object; the ultrahigh frequency RFID scanning system continuously scans the scanned object, till no new data is added to a scan set A, and then counting is started; if no new data is added to the scan set A for N consecutive scan cycles, it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the scanned object. The present invention overcomes the problem that neither the setting of “reading time” nor the setting of “number of times of reading” can determine whether the ultrahigh frequency RFID scanning system has actually read all the RFID tags.

Claims

1. A method for reading ultrahigh frequency RFID (Radio Frequency Identification) tags in a scanned object, wherein: an ultrahigh frequency RFID scanning system comprises an ultrahigh frequency RFID reader (1) and an antenna group; the antenna group comprises at least two antennas (2); the antennas (2) are distributed around the scanned object (4); the RFID tags are in the scanned object (4); the antennas (2) are respectively connected to the ultrahigh frequency RFID reader (1) through feeders; a quantity of the RFID tags placed in each scanned object (4) is different; the antennas (2) are arranged in a tunnel machine (3); the scanned object (4) is arranged on a conveyor line (5); the conveyor line (5) passes through the tunnel machine (3); and the method for reading the ultrahigh frequency RFID tags is embedded in the ultrahigh frequency RFID scanning system; the method comprises steps of: setting a scan set A of the quantity of the RFID tags in the scanned object (4); adding new data of every scan cycle to the scan set A; continuously scanning the scanned object (4) by the ultrahigh frequency RFID scanning system, till no new data is added to the scan set A, and then starting counting; wherein: if no new data is added to the scan set A for N consecutive scan cycles, it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the scanned object (4); if new data is added to the scan set A in any one of N consecutive scan cycles, counting is restarted, till no new data is added to the scan set A for N consecutive scan cycles, and it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the scanned object (4); wherein: the number N of consecutive scan cycles is adjusted according to the quantity of the RFID tags in the scanned object (4) or reading difficulty of the RFID tags; a detecting device is arranged on the conveyor line (5); the detecting device estimates the quantity of the RFID tags in the scanned object (4) and feeds an estimated result back to the ultrahigh frequency RFID reader (1); according to the estimated result, the ultrahigh frequency RFID reader (1) selects an appropriate number N of consecutive scan cycles.

2. The method, as recited in claim 1, wherein: before scanning, the ultrahigh frequency RFID scanning system presets the number N of consecutive scan cycles; and the number N of consecutive scan cycles is a natural number ranging from 3 to 20.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The FIGURE is a sketch view of an ultrahigh frequency RFID (Radio Frequency Identification) scanning system according to a preferred embodiment of the present invention.

(2) In the FIGURE: 1: ultrahigh frequency RFID reader; 2: antenna; 3: tunnel machine; 4: scanned object; and 5: conveyor line.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(3) According to the preferred embodiment of the present invention, a method for reading ultrahigh frequency RFID (Radio Frequency Identification) tags is provided, wherein: an ultrahigh frequency RFID scanning system comprises an ultrahigh frequency RFID reader 1 and an antenna group; the antenna group comprises at least two antennas 2; the antennas 2 are distributed around a scanned object 4; the RFID tags are in the scanned object 4; and the antennas 2 are respectively connected to the ultrahigh frequency RFID reader 1 through feeders;

(4) the method comprises steps of: setting a scan set A of a quantity of the RFID tags in the scanned object 4; adding new data of every scan cycle to the scan set A; continuously scanning the scanned object 4 by the ultrahigh frequency RFID scanning system, till no new data is added to the scan set A, and then starting counting; wherein: if no new data is added to the scan set A for N consecutive scan cycles, it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the scanned object 4; if new data is added to the scan set A in any one of N consecutive scan cycles, counting is restarted, till no new data is added to the scan set A for N consecutive scan cycles, and it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the scanned object 4.

(5) Furthermore, the number N of consecutive scan cycles is adjusted according to the quantity of the RFID tags in the scanned object 4 or reading difficulty of the RFID tags.

(6) Furthermore, before scanning, the ultrahigh frequency RFID scanning system presets the number N of consecutive scan cycles; and the number N of consecutive scan cycles is a natural number ranging from 3 to 20.

(7) Furthermore, the antennas 2 are arranged in a tunnel machine 3; the scanned object 4 is arranged on a conveyor line 5; the conveyor line 5 passes through the tunnel machine 3; and the method for reading the ultrahigh frequency RFID tags is embedded in the ultrahigh frequency RFID scanning system.

(8) Furthermore, a detecting device is arranged on the conveyor line 5; the detecting device estimates the quantity of the RFID tags in the scanned object 4 and feeds an estimated result back to the ultrahigh frequency RFID reader 1; according to the estimated result, the ultrahigh frequency RFID reader 1 selects an appropriate number N of consecutive scan cycles.

(9) The present invention is further illustrated with an example of scanning an object on the conveyor line as follows.

(10) Referring to the FIGURE, the tunnel machine 3 is arranged on the conveyor line 5; the ultrahigh frequency RFID scanning system is arranged in the tunnel machine 3; the ultrahigh frequency RFID scanning system comprises the ultrahigh frequency RFID reader 1 and the antenna group; the ultrahigh frequency RFID reader 1 is arranged on the tunnel machine 3; the antennas 2 are respectively connected to the ultrahigh frequency RFID reader 1 through the feeders; the scanned object 4 is a carton; different quantity of products (such as clothes, wherein each of the clothes is provided with the RFID tag) are placed in each carton.

(11) The RFID tags are cyclically read by the antenna group; one reading cycle is set as a scan cycle of the ultrahigh frequency RFID reader (scan cycle for short).

(12) Before the carton passes through the tunnel machine 3, the ultrahigh frequency RFID scanning system presets the number N of consecutive scan cycles, or the detecting device (such as the weighing device) estimates the quantity of the RFID tags in the carton and then an appropriate number N of consecutive scan cycles is selected.

(13) When the carton passes through the tunnel machine 3, the carton stays for a short time.

(14) The scan set A of the quantity of the RFID tags in the carton is set; the new data of every scan cycle is added to the scan set A; the ultrahigh frequency RFID scanning system continuously scans the carton, till no new data is added to the scan set A, and then counting is started; if no new data is added to the scan set A for N consecutive scan cycles, it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the carton; if new data is added to the scan set A in any one of N consecutive scan cycles, counting is restarted, till no new data is added to the scan set A for N consecutive scan cycles, and it is considered that the ultrahigh frequency RFID scanning system has read all the RFID tags in the carton.

(15) The number N of consecutive scan cycles is adjusted according to the quantity of the RFID tags in the scanned object 4 or reading difficulty of the RFID tags.

(16) After scanning is completed, the carton is removed through the conveyor line.