Wireless tag reader

Patent metadata

Field	Value
Publication number	US-11475228-B2
Application number	US-202117152500-A
Country	US
Kind code	B2
Filing date	Jan 19, 2021
Priority date	Mar 18, 2020
Publication date	Oct 18, 2022
Grant date	Oct 18, 2022

Abstract

According to one or more embodiments, a wireless tag reader includes a first shield member, a second shield member, an antenna, and a reader. The first and second shield members face each other across a reading area through which a wireless tag can pass. Each of the first and second shield members has a reflective surface that reflects a radio wave incident thereon toward the reading area. The antenna is between the reading area and the reflective surface of one of the first and second shield members. The antenna radiates and receives radio waves to communicate with the wireless tag. The reader reads data stored in the wireless tag based on radio waves received from the wireless tag by the antenna.

First claim

What is claimed is:

1. A wireless tag reader, comprising:
a first shield member and a second shield member facing each other across a reading area through which a wireless tag attached to an article can pass, each of the first and second shield members comprising a reflective surface configured to reflect radio waves incident thereon toward the area;
an antenna between the reading area and the reflective surface of at least one of the first and second shield members, the antenna configured to radiate and receive radio waves for communicating with the wireless tag;
a reader configured to read data stored in the wireless tag based on radio waves received from the wireless tag by the antenna; and
a wave director between the antenna and the reading area, the wave director configured to control directivity of radio waves from the antenna, wherein
the wave director comprises a first wave directing element configured to radiate a first radio wave in response to a radio wave from the antenna.

2. The wireless tag reader according to claim 1 , wherein the reading area is in an aisle between the first and second shield members.

3. The wireless tag reader according to claim 1 , wherein the reflective surface of at least one of the first and second shield members is a concave surface configured to reflect radio waves to a focal point in the reading area.

4. The wireless tag reader according to claim 1 , wherein the reflective surface of at least one of the first and second shield members has a parabolic shape.

5. The wireless tag reader according to claim 1 , wherein the reflective surface of the first shield member and the reflective surface of the second shield member are symmetric to each other with respect to the reading area.

6. The wireless tag reader according to claim 1 , wherein the antenna comprises a radiation surface facing the reading area, the radiation surface configured to radiate radio waves to the reading area and receive radio waves from the wireless tag.

7. The wireless tag reader according to claim 6 , wherein the radiation surface is further configured to perform multi-reflection of the radio wave.

8. The wireless tag reader according to claim 1 , wherein the first wave directing element is spaced from the antenna by a distance equal to ¼ wavelength of the radio wave from the antenna.

9. The wireless tag reader according to claim 1 wherein the first radio wave from the first wave directing element has a phase delayed by a half wavelength from the radio wave from the antenna.

10. The wireless tag reader according to claim 1 wherein the wave director further comprises a second wave directing element spaced from the first second wave directing element by a distance equal to ¼ wavelength of the radio wave from the antenna.

11. The wireless tag reader according to claim 1 , further comprising:
a choke structure at an outer edge portion of one of the first and second shield members, the choke structure configured to suppress propagation of radio waves from the antenna to a back side of the one of the first and second shield members.

12. The wireless tag reader according to claim 11 , wherein the choke structure comprises a wave guide into which radio waves enters and a groove by which the radio waves from the wave guide are reflected back to the wave guide.

13. A wireless tag reader, comprising:
a first shield member comprising a first concave reflective surface;
a second shield member comprising a second concave reflective surface and facing the first shield member across an aisle of a tag gate, each of the first and second concave reflective surfaces configured to reflect radio waves toward a tag reading area in the aisle of the tag gate;
an antenna configured to radiate radio waves toward the tag reading area and receive radio waves from a wireless tag in the tag reading area; and
a wave choke configured to suppress propagation of radio waves from the antenna to a back side of the one of the first and second shield members.

14. The wireless tag reader according to claim 13 , further comprising:
a wave director configured to direct radio waves from the antenna toward the tag reading area.

15. The wireless tag reader according to claim 13 , wherein the antenna is between the tag reading area and the concave reflective surface of the at least one of the first and second shield members.

16. The wireless tag reader according to claim 13 , wherein each of the first and second reflective surfaces has a parabolic shape.

17. The wireless tag reader according to claim 14 , wherein the wave director comprises a first wave directing element configured to radiate a first radio wave in response to a radio wave from the antenna.

18. The wireless tag reader according to claim 17 , wherein the first wave directing element is spaced from the antenna by a distance equal to ¼ wavelength of the radio wave from the antenna.

19. A wireless tag reader, comprising:
an antenna configured to transmit and receive signals to and from a wireless tag in a tag reading area;
a pair of shield members with the tag reading area therebetween, each shield member of the pair of shield members comprising a reflective surface configured to reflect signals from the antenna to a focal point within the tag reading area;
a wave directing element configured to radiate a first radio wave in response to a radio wave from the antenna; and
a reader configured to read data of the wireless tag based on a signal received from the wireless tag by the antenna, wherein
the antenna is between the tag reading area and at least one of the first and second reflective surfaces, and
the wave directing element is between the antenna and the tag reading area.

20. The wireless tag reader according to claim 19 , further comprising:
a choke structure at an outer edge portion of one of the pair of shield members, the choke structure configured to suppress propagation of radio waves from the antenna to a back side of the one of the pair of shield members.

Assignees

• Toshiba Tec Kk

Inventors

• Kawabe Yuichiro

Classifications

• G06K7/10009

  sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves · CPC title

• H01Q19/022

  for reducing the edge scattering of reflectors · CPC title

• G06K7/10346

  the antenna being of the far field type, e.g. HF types or dipoles · CPC title

• G06K7/10297 Primary

  arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 (cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00) · CPC title

• G06K2007/10504

  Data fields affixed to objects or articles · CPC title