Tag detecting system, moving object detecting method, and entrance/exit management system
First Claim
Patent Images
1. A tag detecting system comprising:
- a first generator emitting a pulse code modulated signal of a predetermined intensity through a first antenna;
a second generator emitting a pulse code modulated signal of a predetermined intensity through a second antenna;
an RFID tag detecting the pulse code modulated signal from the first antenna and the second antenna, and transmitting a discrimination signal by responding to the pulse code modulated signal; and
a receiver receiving the discrimination signal through a receiving antenna, whereinthe first antenna and the second antenna are adjacently arranged to produce a cross over area between high-frequency magnetic fields formed by both the first and second antennas,each of the first generator and the second generator emits the pulse code modulated signal at such a timing that spaces included in a predetermined part of the pulse code modulated signal emitted by any one of the first and second generators is occupied by the pulse code modulated signal emitted by the other the first and second generators, andthe RFID tag is made not to detect the pulse code modulated signals due to the spaces being occupied, if the RFID tag is located in the cross over area or a part of the cross over area.
3 Assignments
0 Petitions
Accused Products
Abstract
A tag detecting system for detecting a movement of a person or an object that mounts an RFID tag, a moving object detecting method, and an entrance/exit management system using the moving object detecting system are provided. The tag detecting system detects a specific person or object by restricting a detection area of the RFID tag to a narrow area. Since the moving object detecting method detects a piggyback, the entrance/exit system prevents the piggyback even if there are a number of persons passing through an entrance/exit gate almost at the same time.
38 Citations
35 Claims
-
1. A tag detecting system comprising:
-
a first generator emitting a pulse code modulated signal of a predetermined intensity through a first antenna; a second generator emitting a pulse code modulated signal of a predetermined intensity through a second antenna; an RFID tag detecting the pulse code modulated signal from the first antenna and the second antenna, and transmitting a discrimination signal by responding to the pulse code modulated signal; and a receiver receiving the discrimination signal through a receiving antenna, wherein the first antenna and the second antenna are adjacently arranged to produce a cross over area between high-frequency magnetic fields formed by both the first and second antennas, each of the first generator and the second generator emits the pulse code modulated signal at such a timing that spaces included in a predetermined part of the pulse code modulated signal emitted by any one of the first and second generators is occupied by the pulse code modulated signal emitted by the other the first and second generators, and the RFID tag is made not to detect the pulse code modulated signals due to the spaces being occupied, if the RFID tag is located in the cross over area or a part of the cross over area. - View Dependent Claims (2, 3)
-
-
4. A tag detecting system comprising:
-
a first generator emitting a pulse code modulated signal through a first antenna of a predetermined field strength; a second generator emitting a pulse code modulated signal through a second antenna of a predetermined field strength; a third generator emitting a pulse code modulated signal through a third antenna of a predetermined field strength; an RFID tag detecting the pulse code modulated signal at least from the first antenna, the second antenna and the third antenna, and transmitting a discrimination signal by responding to the pulse code modulated signal; and a receiver receiving the discrimination signal through a receiving antenna, wherein the first antenna and the second antenna are adjacently arranged to produce a first cross over area where high-frequency magnetic fields formed by both antennas are overlaid each other; the first antenna and the third antenna are adjacently arranged to produce a second cross over area where high-frequency magnetic fields formed by both antennas are overlaid each other; each of the first generator and the second generator emits the pulse code modulated signal at such a timing that spaces included in a predetermined part of the pulse code modulated signal emitted by any one of the first and second generators is occupied by the pulse code modulated signal emitted by the other of the first and second generators; each of the first generator and the third generator emits the pulse code modulated signal at such a timing that spaces included in a predetermined part of the pulse code modulated signal emitted by any one of the first and third generators is occupied by the pulse code modulated signal emitted by the other of the first and third generators; and a detection area in which the RFID tag is capable of detecting the pulse code modulated signal from the first antenna, is made to be restricted so that the RFID tag is made not to detect the pulse code modulated signals due to the spaces being occupied, if the RFID tag is located in the first cross over area or the second cross over area, or a part of the first cross over area or the second cross over area. - View Dependent Claims (5, 6, 7, 8)
-
-
9. A moving object detecting method for detecting a movement of an object mounting an RFID tag comprised of:
-
a step that a plurality of trigger antennas respectively form high-frequency magnetic fields in which there is a cross over area where parts of the magnetic fields are adjacently overlaid; a step that a plurality of generators emit pulse cord modulated signals corresponding to the respective high-frequency magnetic fields, and generate cross over trigger signals by overlaying the respective pulse code modulated signals in the cross over area; a step that an integrated circuit mounted on the RFID tag receives and transmits ID information corresponding to the pulse code modulated signal in the respective high-frequency magnetic fields; and a step that the integrated circuit receives and transmits ID information corresponding to the cross over trigger signal when the integrated circuit detects the cross over trigger signal in the cross over area.
-
-
10. An entrance/exit management system for monitoring a movement of a person having an RFID tag including:
-
a plurality of trigger antennas which form high-frequency magnetic fields respectively in which there is a cross over area where adjacent magnetic fields are partially overlaid; and an integrated circuit which is mounted on the RFID tag, detects respective trigger signals included in the magnetic field of the respective high-frequency magnetic fields, and receives and transmits ID information corresponding to the respective trigger signals, wherein the integrated circuit does not receive and transmit the ID information in the cross over area, when the integrated circuit detects a cross over trigger signal formed by the respective trigger signals contained in the magnetic fields overlaid. - View Dependent Claims (11, 12, 13, 14)
-
-
15. An entrance/exit management system for monitoring a movement of a person having an RFID tag comprising:
-
three trigger antennas which respectively form high-frequency magnetic fields having cross over areas in which adjacent magnetic fields are partially overlaid; the RFID tag which includes an integrated circuit; and the integrated circuit which detects respective pulse code modulated signals included in magnetic fields of the respective high-frequency magnetic fields, receives and transmits ID information corresponding to the respective pulse code modulated signals, and does not detect a cross over trigger signal in which the pulse code modulated signals included in the magnetic fields are overlaid, at least in a partial area of the cross over area;
whereinthe integrated circuit detects a direction of movement of the RFID tag based on a process that ID information changes corresponding to the respective pulse code modulated signals, and the integrated circuit discriminates the specific RFID tag in the high-frequency magnetic field located between the partial areas. - View Dependent Claims (16, 17)
-
-
18. A moving object detecting method for detecting a movement of an object mounting an RFID tag comprising:
-
a step of forming a first high-frequency magnetic field corresponding to a first pulse code modulated signal including first trigger ID information and a second high-frequency magnetic field corresponding to a second pulse code modulated signal including second trigger ID information, such that there is a first cross over area where a part of the magnetic fields is adjacently overlaid, wherein the RFID tag includes a three-dimensional coil and an integrated circuit composing vector values of the three-dimensional high-frequency magnetic fields, received by the three- dimensional coil, thereby to output signal levels as scalar values, and if a part of the first pulse code modulated signal and the second pulse code modulated signal is overlaid when the signal levels of the scalar values are the same, at least a part of spaces of the modulated signals is occupied, which makes the RFID tag incapable of detecting the modulated signals, and a step of transmitting a signal including trigger ID information corresponding to the pulse code modulated signal at the larger signal level and tag ID information of the RFID itself by the RFID tag, if a ratio of the signal levels is smaller than a threshold value;
a larger signal level being defined as a denominator by comparing the first pulse code modulated signal thus received to the second pulse code modulated signal thus received, in the first cross over area using the scalar values of the signal levels, anda step of transmitting no signal including the tag ID information of the RFID tag itself by the RFID tag, if the ratio of the signal levels is larger than the threshold value. - View Dependent Claims (19, 20, 21, 22, 23)
-
-
24. A tag detecting system comprising:
-
a first generator emitting a first pulse code modulated signal including first trigger ID information to a first antenna, and forming a first high-frequency magnetic field corresponding to the first pulse code modulated signal through the first antenna; a second generator emitting a second pulse code modulated signal including second trigger ID information to a second antenna, and forming a second high-frequency magnetic field corresponding to the second pulse code modulated signal through the second antenna; and an RFID tag including a three-dimensional coil and an integrated circuit composing vector values of the three-dimensional high-frequency magnetic fields, received by the three- dimensional coil, thereby to output signal levels as scalar values, wherein the first and the second high-frequency magnetic fields are formed such that there is a first cross over area where a part of the first and the second high-frequency magnetic fields is adjacently overlaid; if a part of the first pulse code modulated signal and the second pulse code modulated signal is overlaid when the signal levels of the scalar values are the same, at least a part of spaces of the modulated signals is occupied, which makes the RFID tag incapable of detecting the first pulse code modulated signal and the second pulse code modulated signal, the RFID tag transmits a signal including trigger ID information corresponding to the pulse code modulated signal at a larger signal level and tag ID information of the RFID itself, if a ratio of the signal levels is smaller than a threshold value;
the larger signal level being defined as a denominator by comparing the first pulse code modulated signal thus received to the second pulse code modulated signal thus received, in the first cross over area using the scalar values of the signal levels, andthe RFID tag transmits no signal including the tag ID information of itself, if the ratio of the signal levels is larger than the threshold value. - View Dependent Claims (25, 26, 27, 28, 29)
-
-
30. An entrance / exit management system for monitoring a movement of a person having an RFID tag comprising:
-
a first generator emitting a first pulse code modulated signal including first trigger ID information to a first antenna, and forming a first high-frequency magnetic field corresponding to the first pulse code modulated signal through the first antenna; a second generator emitting a second pulse code modulated signal including second trigger ID information to a second antenna, and forming a second high-frequency magnetic field corresponding to the second pulse code modulated signal through the second antenna, in which the first and the second high-frequency magnetic fields are formed such that there is a first cross over area where a part of the first and the second high-frequency magnetic fields is adjacently overlaid, wherein the RFID tag includes a three-dimensional coil and an integrated circuit composing vector values of the three-dimensional high-frequency magnetic fields, received by the three- dimensional coil, thereby to output signal levels as scalar values; if a part of the first pulse code modulated signal and the second pulse code modulated signal is overlaid when the signal levels of the scalar values are the same, at least a part of spaces of the modulated signals is occupied, which makes the RFID tag incapable of detecting the first pulse code modulated signal and the second pulse code modulated signal; the RFID tag transmits a signal including trigger ID information corresponding to the pulse code modulated signal at a larger signal level and tag ID information of the RFID itself, if a ratio of the signal levels is smaller than a threshold value;
the larger signal level being defined as a denominator by comparing the first pulse code modulated signal thus received to the second pulse code modulated signal thus received, in the first cross over area using the scalar values of the signal levels, andthe RFID tag transmits no signal including the tag ID information of itself, if the ratio of the signal levels is larger than the threshold value. - View Dependent Claims (31, 32, 33, 34, 35)
-
Specification