Radio frequency identification reader antenna and shelf

Patent metadata

Field	Value
Publication number	US-9306286-B2
Application number	US-201113981068-A
Country	US
Kind code	B2
Filing date	Jan 20, 2011
Priority date	Jan 20, 2011
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A radio frequency identification (RFID) reader antenna includes a feeding frame, a upper stub unit connected with the first side of the feeding frame, and a lower stub unit connected with the second side of the feeding frame, wherein the upper stub unit includes M first stubs extending towards the second side of the feeding frame, the lower stub unit includes N second stubs extending towards the first side of the feeding frame, the M first stubs and the N second stubs are arranged alternately intervallic, where M, N are integers that are greater than one.

First claim

The invention claimed is:

1. A radio frequency identification (RFID) reader antenna, comprising:
a feeding frame;
an upper stub unit; and
a lower stub unit;
wherein the feeding frame comprises a feed source end, a first side, a load end, and a second side that are sequentially connected, the upper stub unit is connected to the first side of the feeding frame, and the lower stub unit is connected to the second side of the feeding frame;
wherein the upper stub unit includes M first stubs extending toward the second side of the feeding frame, and the lower stub unit includes N second stubs extending toward the first side of the feeding frame, the M first stubs and the N second stubs being arranged alternately, and M and N being integers greater than 1; and
wherein at least one of (i) a width of the first side of the feeding frame narrows in a direction from a feed source end to a load end and (ii) a width of the second side of the feeding frame narrows in a direction from the feed source end to the load end.

2. The RFID reader antenna as claimed in claim 1 , wherein at least one of (i) a distance between two adjacent first stubs in the upper stub unit is set to D 1 to ensure opposite current phases on the two adjacent first stubs and (ii) a distance between two adjacent second stubs in the lower stub unit is set to D 2 to ensure opposite current phases on the two adjacent second stubs.

3. The RFID reader antenna as claimed in claim 1 , wherein at least one of (i) a distance D 1 between two adjacent first stubs in the upper stub unit is an odd multiple of λ/2 and (ii) a distance D 2 between two adjacent second stubs in the lower stub unit is an odd multiple of λ/2, λ being an operating wavelength of the RFID reader antenna.

4. The RFID reader antenna as claimed in claim 1 , wherein a distance between two adjacent first and second stubs is set to D 3 to obtain a maximum current intensity when a first connection point between the first stub and the feeding frame is different from a second connection point between the second stub and the feeding frame.

5. The RFID reader antenna as claimed in claim 1 , wherein a distance D 3 between two adjacent first and second stubs is an odd multiple of λ/4, λ being an operating wavelength of the RFID reader antenna.

6. The RFID reader antenna as claimed in claim 1 , wherein a gap between each first stub and the second side of the feeding frame is set to G 1 , and a gap between each second stub and the first side of the feeding frame is set to G 2 such that current peaks of two adjacent first and second stubs on a same horizontal line do not appear at the same time.

7. The RFID reader antenna as claimed in claim 1 , wherein at least one of (i) a gap G 1 between each first stub and the second side of the feeding frame is an odd multiple of λ/4 and (ii) a gap G 2 between each second stub and the first side of the feeding frame is an odd multiple of λ/4, λ being an operating wavelength of the reader.

8. The RFID reader antenna as claimed in claim 1 , wherein at least one of (i) a length L 1 of each first stub is an integral multiple of λ/2 and (ii) a length L 2 of each second stub is an integral multiple of λ/2, λ being an operating wavelength of the RFID reader antenna.

9. The RFID reader antenna as claimed in claim 1 , wherein the feeding frame is a strip line having a matched load.

10. The RFID reader antenna as claimed in claim 1 , wherein the feeding frame, the upper stub unit and the lower stub unit are located on the same plane.

11. The RFID reader antenna as claimed in claim 10 , wherein the plane at which the feeding frame, the upper stub unit and the lower stub unit are located comprises a base plate of a printed circuit board (PCB).

12. A shelf comprising:
a radio frequency identification (RFID) reader antenna, comprising:
a feeding frame;
an upper stub unit; and
a lower stub unit;
wherein the feeding frame comprises a feed source end, a first side, a load end, and a second side that are sequentially connected, the upper stub unit is connected to the first side of the feeding frame, and the lower stub unit is connected to the second side of the feeding frame;
wherein the upper stub unit includes M first stubs extending toward the second side of the feeding frame, and the lower stub unit includes N second stubs extending toward the first side of the feeding frame, the M first stubs and the N second stubs being arranged alternately, and M and N being integers greater than 1;
wherein the RFID reader antenna is provided in one or more layers of the shelf; and
wherein at least one of (i) a width of the first side of the feeding frame narrows in a direction from a feed source end to a load end and (ii) a width of the second side of the feeding frame narrows in a direction from the feed source end to the load end.

13. A radio frequency identification (RFID) reader antenna, comprising:
a feeding frame;
an upper stub unit; and
a lower stub unit;
wherein the feeding frame comprises a feed source end, a first side, a load end, and a second side that are sequentially connected, the upper stub unit is connected to the first side of the feeding frame, and the lower stub unit is connected to the second side of the feeding frame;
wherein the upper stub unit includes M first stubs extending toward the second side of the feeding frame, and the lower stub unit includes N second stubs extending toward the first side of the feeding frame, the M first stubs and the N second stubs being arranged alternately, and M and N being integers greater than 1; and
wherein a gap between each first stub and the second side of the feeding frame is set to G 1 , and a gap between each second stub and the first side of the feeding frame is set to G 2 such that current peaks of two adjacent first and second stubs on a same horizontal line do not appear at the same time.

14. A radio frequency identification (RFID) reader antenna, comprising:
a feeding frame;
an upper stub unit; and
a lower stub unit;
wherein the feeding frame comprises a feed source end, a first side, a load end, and a second side that are sequentially connected, the upper stub unit is connected to the first side of the feeding frame, and the lower stub unit is connected to the second side of the feeding frame;
wherein the upper stub unit includes M first stubs extending toward the second side of the feeding frame, and the lower stub unit includes N second stubs extending toward the first side of the feeding frame, the M first stubs and the N second stubs being arranged alternately, and M and N being integers greater than 1; and
wherein at least one of (i) a gap G 1 between each first stub and the second side of the feeding frame is an odd multiple of λ/4 and (ii) a gap G 2 between each second stub and the first side of the feeding frame is an odd multiple of λ/4, λ being an operating wavelength of the reader.

Assignees

• Horst Dieter
• Yu Dan
• Yuan Yong
• Siemens Ag

Inventors

• Horst Dieter
• Yu Dan
• Yuan Yong

Classifications

• G06K7/10356 Primary

  using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas · CPC title

• H01Q13/20

  Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave · CPC title

• H01Q9/0407 Primary

  Substantially flat resonant element parallel to ground plane, e.g. patch antenna (dipole H01Q9/285; monopole H01Q9/40) · CPC title

• H01Q1/2216

  used in interrogator/reader equipment · CPC title

• G06K2017/0051

  Physics · mapped topic