Wireless IC tag, wireless IC tag system and operation method for wireless IC tag
First Claim
1. A wireless IC tag comprising:
- an antenna;
a power supply circuit; and
a demodulation circuit,wherein the antenna receives a first radio wave obtained by amplitude modulating a carrier wave having a first frequency by an information signal and a second radio wave having a second frequency,wherein the power supply circuit generates a power supply voltage from a signal induced in the antenna by the first radio wave and the second radio wave, andwherein the demodulation circuit demodulates the information signal from the signal.
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Accused Products
Abstract
A wireless IC tag system according to the present invention is provided with a wireless IC tag, a reader/writer device and a high-frequency signal output device. The reader/writer device outputs a first high-frequency signal. The high-frequency signal output device outputs a second high-frequency signal only during a period when the reader/writer device outputs the first high-frequency signal. The wireless IC tag is provided with an antenna, a power supply circuit and a communication circuit. The antenna receives the first and second high-frequency signals. The power supply circuit generates a power supply voltage from the first and second high-frequency signals. The communication circuit transmits and receives an information signal to and from the reader/writer device by utilizing the first high-frequency signal.
33 Citations
20 Claims
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1. A wireless IC tag comprising:
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an antenna; a power supply circuit; and a demodulation circuit, wherein the antenna receives a first radio wave obtained by amplitude modulating a carrier wave having a first frequency by an information signal and a second radio wave having a second frequency, wherein the power supply circuit generates a power supply voltage from a signal induced in the antenna by the first radio wave and the second radio wave, and wherein the demodulation circuit demodulates the information signal from the signal. - View Dependent Claims (2, 3, 4)
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5. A wireless IC tag system comprising:
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a wireless IC tag; a first transmitting device for transmitting a first radio wave obtained by amplitude modulating a carrier wave having a first frequency by an information signal to the wireless IC tag; and a second transmitting device for transmitting a second radio wave having a second frequency to the wireless IC tag, wherein the wireless IC tag has an antenna, a power supply circuit and a demodulation circuit, wherein the antenna receives the first radio wave and the second radio wave, wherein the power supply circuit generates a power supply voltage from a signal induced in the antenna by the first radio wave and the second radio wave, and wherein the demodulation circuit demodulates the information signal from the signal. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13)
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14. An operation method for a wireless IC tag,
wherein, to a wireless IC tag that receives a first radio wave having a first frequency and a second radio wave having a second frequency by an antenna, generates a power supply voltage from a signal induced in the antenna and demodulates an information signal from the signal, a first radio wave obtained by amplitude modulating a carrier wave having the first frequency by the information signal is transmitted from a first transmitting device, and wherein a second radio wave having the second frequency is transmitted from a second transmitting device to the wireless IC tag.
Specification