Method for employing a RFID walk-through gate

1. A method for tag detection by using a walk-through gate (WTG), the method comprising:

constructing a WTG structure including a first wall and a second wall, the first and second walls defining a walk-through pass way between an entrance and an exit;

positioning at least one sensor at the entrance and the exit of a cavity defined by the walk-through pass way;

positioning at least one first antenna facing toward an inside region of the WTG structure;

positioning at least one second antenna facing away from the inside region of the WTG structure;

connecting a radio frequency identification (RFID) reader to the at least one first and second antennas; and

judging, via a judgement module, if an RFID tag is located inside or outside the walk-through gate structure;

constructing curved surface structures in both the first and second walls of the WTG structure, the curved surface structures extending an entire height of the first and second walls,

wherein an angle of curvature of the curved surface structures is given as:

(1−cos(α=2))=2 sin(α=2)= W=L,

where W is a width of the first and second walls, L is a length of the first and second walls, and α is the angle of curvature;

wherein a pair of absorbers are disposed within each of the first and second walls, the pair of absorbers extending the entire height of the first and second walls,

wherein a session has a minimum duration time and a maximum duration time, and

wherein a session time is dynamically adjusted by a judgement algorithm of the judgement module.

2. The method of claim 1 ,

wherein the at least one sensor at the entrance of the WTG structure senses when a user enters the WTG structure; and

wherein the at least one sensor at the exit of the WTG structure senses when the user exits the WTG structure.

3. The method of claim 2 , wherein the WTG is in session within a time period defined as when the user enters and exits the WTG.

4. The method of claim 1 , wherein in each session, the RFID reader enables an interrogation from the at least one first and second antennas by cycling through the at least one first and second antennas in a predetermined order.

5. The method of claim 1 , wherein a session duration time is based on a number of antenna cycles.

6. The method of claim 1 , wherein a session start time is enabled by explicit user interaction such as scanning a card, pushing a button, and interacting with an interactive device such as tablet or touch screen display.

7. The method of claim 1 , wherein either side of the walk-through pass way can be used as the entrance and the WTG recognizes a direction of movement.

8. The method of claim 1 , wherein the WTG detects a number of users entering or exiting the WTG.

9. The method of claim 1 , wherein the WTG detects if a user exits from a same side that the user has entered.

10. A method for tag detection by using a walk-through gate (WTG), the method comprising:

constructing a WTG structure including a first wall and a second wall, the first and second walls defining a walk-through pass way between an entrance and an exit;

positioning at least one sensor at the entrance and the exit of a cavity defined by the walk-through pass way;

positioning at least one first antenna facing toward an inside region of the WTG structure;

positioning at least one second antenna facing away from the inside region of the WTG structure;

connecting a radio frequency identification (RFID) reader to the at least one first and second antennas;

judging, via a judgement module, if an RFID tag is located inside or outside the walk-through gate structure; and

constructing curved surface structures in both the first and second walls of the WTG structure, the curved surface structures extending an entire height of the first and second walls,

wherein an angle of curvature of the curved surface structures is given as:

(1−cos(α=2))=2 sin(α=2)= W=L,

where W is a width of the first and second walls, L is a length of the first and second walls, and α is the angle of curvature; and

wherein a pair of absorbers are disposed within each of the first and second walls, the pair of absorbers extending the entire height of the first and second walls.

11. The method of claim 10 , wherein the WTG includes at least two states, that is, an in session state and a not in-session state.

12. The method of claim 11 ,

wherein the WTG changes from the not in-session state to the in session state when a user moves from outside the WTG structure to inside the WTG structure, and the movement is detected by the at least one sensor at the entrance; and

wherein the WTG changes from the in session state to the not in-session state when the user moves from inside the WTG structure to outside the WTG structure, and this motion is detection by the at least one sensor at the exit.

13. The method of claim 11 , wherein the not in-session state is further divided into two states, that is, a ready-to-verify state and a verified state.

14. The method of claim 13 , wherein the WTG changes from the ready-to-verify state to the verified state after user identity is verified.

15. The method of claim 14 , wherein a verification process employs face recognition, an identification card, or combination thereof.

16. The method of claim 11 , wherein the in session state is further divided into two states, that is, a judgment-period state and a judgment-completed state.

17. The method of claim 16 , wherein the WTG changes from the judgment-period state to the judgment-completed state when a judgement algorithm has been completed.

18. The method of claim 17 ,

wherein a user is notified when the user can exit the walk-through pass way only after the WTG enters the judgment-completed state; and

wherein the user is notified when the user can enter the walk-through pass way only after the WTG enters a verified state.