Radio frequency identification tag identification system

• US 10,262,173 B2
• Filed: 04/03/2017
• Issued: 04/16/2019
• Est. Priority Date: 03/30/2009
• Status: Active Grant

• Current Assignee: Datalogic USA, Inc.
• Original Assignee: Datalogic USA, Inc.
• Inventors: Goidas, Peter J., Liu, Zhong-Min, Brockmole, Jeffrey M., Kulakkunnath, Kapilkumar N.
• Primary Examiner(s): Alam, Mirza F
• Application Number:
  US15/478,224
• Publication Number:
  US 20170206387A1
• Time in Patent Office: 743 Days
• Field of Search: 3405721, 3405727, 3405724, 340 101, 3405723, 340928, 340551, 3405729, 340505, 340506, 34053913, 343742, 343866, 343745, 343748, 343893, 343726, 343855, 235385, 235384, 235375, 235382, 705 22
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10435 the interrogation device being positioned close to a conveyor belt or the like on which moving record carriers are passing conveying in accordance with bodily destination marks, see B65G47/46, sorting of objects carrying identity markings, see B07C5/34
• CPC Class Codes: G06K 7/10445 the record carriers being fixed to further objects, e.g. RFIDs fixed to packages, luggage, mail-pieces or work-pieces transported on a conveyor belt
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001

Abstract

A conveyor system for processing items on which radio frequency identification tags are disposed has a conveyor that conveys items through a path of travel, and an antenna disposed proximate the path of travel. Circuitry in communication with the antenna may associate RFID tag data with a package on the conveyor based on a difference signal from elements in the antenna.

Claims

1. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:

a conveyor that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon;

an antenna; and

circuitry comprising a radio frequency transmitter, a receiver, and a feed network between the transmitter and the antenna, wherein the transmitter is capable of driving the antenna via the feed network to radiate radio frequency signals to which the at least one respective radio frequency identification tag is responsive to transmit a response signal to the receiver, and wherein the antenna is disposed with respect to the path of travel so that the antenna radiates the radio frequency signals into an area through which the items pass,

wherein the circuitry is selectable between at least two operative states,

wherein, in a first said operative state, the transmitter drives the antenna to emit the radio frequency signals in a first radiation pattern,

wherein, in a second said operative state, the transmitter drives the antenna to emit the radio frequency signals in a second radiation pattern that is different from the first radiation pattern,

wherein said first and second radiation patterns occupy respective volumes within which the at least one respective radio frequency identification tag receives and emits responses to the radio frequency signals,

wherein the circuitry comprises a switch within the feed network that is controllable between two states that define respective different lengths of the feed network to thereby define the first operative state and the second operative state, and

wherein the first radiation pattern has a length in the path of travel at the area that is greater than a length of the second radiation pattern in the path of travel at the area.

2. The conveyor system as in claim 1, wherein the antenna is a patch array antenna.

3. The conveyor system as in claim 1, wherein the circuitry is in communication with the conveyor so that the circuitry identifies the items on the conveyor, including a distance between adjacent said items, and wherein the circuitry selects an operative state of the at least two operative states in response to the distance.

4. The conveyor system as in claim 3, wherein the distance is in a direction of the path of travel.

5. The conveyor system as in claim 4, wherein the circuitry comprises:

a sensor disposed proximate the path of travel so that the sensor detects presence of items in the path of travel, and

a computer that receives a signal from the sensor, determines the distance, and controls the radio frequency transmitter in response to the distance.

6. The conveyor system as in claim 1, wherein the circuitry is in communication with the conveyor so that the circuitry identifies a speed of the conveyor, and wherein the circuitry selects an operative state of the at least two operative states in response to the speed.

7. The conveyor system as in claim 6, wherein the speed is in a direction of the path of travel.

8. The conveyor system as in claim 7, wherein the circuitry comprises:

a tachometer in communication with the conveyor, and

a computer that receives a signal from the tachometer, determines the speed, and controls the radio frequency transmitter in response to the speed.

9. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:

a conveyor that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon;

an antenna; and

circuitry comprising a radio frequency transmitter, a receiver, and a feed network between the transmitter and the antenna, wherein the transmitter is capable of driving the antenna via the feed network to radiate radio frequency signals to which the at least one respective radio frequency identification tag is responsive to transmit a response signal to the receiver, wherein the antenna is disposed with respect to the path of travel so that the antenna radiates the radio frequency signals into an area through which the items pass, and wherein the circuitry is in communication with the conveyor so that the circuitry identifies the items on the conveyor, including a distance between adjacent said items, and identifies a speed of the conveyor,

wherein the circuitry is selectable between at least two operative states in response to at least one of the distance and the speed,

wherein, in a first said operative state, the transmitter drives the antenna to emit the radio frequency signals in a first radiation pattern,

wherein, in a second said operative state, the transmitter drives the antenna to emit the radio frequency signals in a second radiation pattern that is different from the first radiation pattern,

wherein said first and second radiation patterns occupy respective volumes within which the at least one respective radio frequency identification tag receives and emits responses to the radio frequency signals,

wherein the first radiation pattern has a length in the path of travel at the area that is greater than a length of the second radiation pattern in the path of travel at the area, and

wherein the circuitry selects the first operative state when the distance is below a first predetermined threshold or when the speed is below a second predetermined threshold.

10. The conveyor system as in claim 9, wherein the circuitry comprises:

a first sensor disposed proximate the path of travel so that the first sensor detects presence of items in the path of travel and a second sensor disposed in communication with the conveyor so that the second sensor detects speed of the conveyor, and

a computer that receives a signal from the first sensor and a signal from the second sensor, determines the distance and the speed, and controls the radio frequency transmitter in response to at least one of the distance and the speed.

11. The conveyor system as in claim 10, wherein the circuitry comprises a switch within the feed network that is controllable between two states that define respective different lengths of the feed network to thereby define the first operative state and the second operative state.