Interference suppression apparatus and interference suppression system

Patent metadata

Field	Value
Publication number	US-11755876-B2
Application number	US-202117349172-A
Country	US
Kind code	B2
Filing date	Jun 16, 2021
Priority date	Jun 16, 2020
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

An interference suppression apparatus suppresses electromagnetic field interference produced by an RFID tag. The interference suppression apparatus includes a power supply circuit, an antenna that is connected to the power supply circuit, a clock that is connected to the power supply circuit, and a load adjuster that is connected to the power supply circuit. The clock generates an output in which a time constant is adjusted to be longer than a communication time of the RFID tag. The load adjuster changes a characteristic of the antenna based on the output from the clock.

First claim

What is claimed is:

1. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a clock that is connected to the power supply circuit and generates an output in which a time constant is adjusted to be longer than a communication time of the radio frequency identification tag; and
a load adjuster that is connected to the power supply circuit and changes a characteristic of the antenna based on the output from the clock, wherein:
the radio frequency identification tag is provided on a label;
the interference suppression apparatus is provided on the same label as the radio frequency identification tag; and
the antenna of the interference suppression apparatus and an antenna of the radio frequency identification tag are arranged so as to be substantially parallel to each other with a predetermined gap therebetween.

2. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a command detector that is connected to the power supply circuit and detects a specific command that is transmitted from a radio frequency identification reading apparatus for radio frequency identification tags; and
a load adjuster that is connected to the power supply circuit and changes a characteristic of the antenna based on the specific command detected by the command detector, wherein:
the radio frequency identification tag is provided on a label;
the interference suppression apparatus is provided on the same label as the radio frequency identification tag; and
the antenna of the interference suppression apparatus and an antenna of the radio frequency identification tag are arranged so as to be substantially parallel to each other with a predetermined gap therebetween.

3. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a clock that is connected to the power supply circuit and generates an output in which a time constant is adjusted to be longer than a communication time of the radio frequency identification tag; and
a load adjuster that is connected to the power supply circuit and changes a characteristic of the antenna based on the output from the clock, wherein:
the antenna is configured by a dipole antenna that includes two elements; and
the load adjuster is configured to change the characteristic of the antenna by setting a state provided between the two elements to an open state, a short-circuit state, or a terminal state which is other than the open state and the short-circuit state.

4. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a clock that is connected to the power supply circuit and generates an output in which a time constant is adjusted to be longer than a communication time of the radio frequency identification tag; and
a load adjuster that is connected to the power supply circuit and changes a characteristic of the antenna based on the output from the clock, wherein:
the antenna has a single element and a grounding surface; and
the load adjuster is configured to change the characteristic of the antenna by setting a state provided between the single element and the grounding surface to an open state, a short-circuit state, or a terminal state other than the open state and the short-circuit state.

5. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a clock that is connected to the power supply circuit and generates an output in which a time constant is adjusted to be longer than a communication time of the radio frequency identification tag; and
a load adjuster that is connected to the power supply circuit and changes a characteristic of the antenna based on the output from the clock, wherein:
the antenna is configured by a resonator; and
the load adjuster is configured to change the characteristic of the antenna by changing behavior of the resonator as an electrical wall, an electromagnetic wall, or an electromagnetic band gap structure.

6. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a command detector that is connected to the power supply circuit and detects a specific command that is transmitted from a radio frequency identification reading apparatus for radio frequency identification tags; and
a load adjuster that is connected to the power supply circuit and is configured to change a characteristic of the antenna based on the specific command detected by the command detector, wherein:
the antenna is configured by a dipole antenna that includes two elements; and
the load adjuster is configured to change the characteristic of the antenna by setting a state provided between provided the two elements to an open state, a short-circuit state, or a terminal state which is other than the open state and the short-circuit state.

7. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a command detector that is connected to the power supply circuit and detects a specific command that is transmitted from a radio frequency identification reading apparatus for radio frequency identification tags; and
a load adjuster that is connected to the power supply circuit and is configured to change a characteristic of the antenna based on the specific command detected by the command detector, wherein:
the antenna has a single element and a grounding surface; and
the load adjuster is configured to change the characteristic of the antenna by setting a state provided between the single element and the grounding surface to an open state, a short-circuit state, or a terminal state other than the open state and the short-circuit state.

8. An interference suppression apparatus that suppresses electromagnetic field interference produced by a radio frequency identification tag, the interference suppression apparatus comprising:
a power supply circuit;
an antenna that is connected to the power supply circuit;
a command detector that is connected to the power supply circuit and detects a specific command that is transmitted from a radio frequency identification reading apparatus for radio frequency identification tags; and
a load adjuster that is connected to the power supply circuit and is configured to change a characteristic of the antenna based on the specific command detected by the command detector, wherein:
the antenna is configured by a resonator; and
the load adjuster is configured to change the characteristi

Assignees

• Denso Wave Inc

Inventors

• Muto Eiji
• Enomoto Kohei
• Masuda Yusuke

Classifications

• G06K19/07771 Primary

  the record carrier comprising means for minimising adverse effects on the data communication capability of the record carrier, e.g. minimising Eddy currents induced in a proximate metal or otherwise electromagnetically interfering object · CPC title

• G06K7/0008 Primary

  General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer · CPC title

• G06K19/07773

  Antenna details (antennas for wireless devices, e.g. RFID tags, in general H01Q1/22) · CPC title