RADIO-FREQUENCY TAG COMMUNICATION DEVICE, RADIO-FREQUENCY TAG COMMUNICATION SYSTEM, AND RADIO-FREQUENCY TAG DETECTING SYSTEM
First Claim
1. A radio-frequency tag communication device arranged to transmit a transmitted signal toward radio-frequency tags, and to receive reply signals transmitted from the radio-frequency tags in response to the transmitted signals, for communication with the radio-frequency tags, said radio-frequency tag communication device comprising:
- a transmission control portion operable to control transmission of said transmitted signal, so as to prevent overlapping of an area of communication of said radio-frequency tag communication device and an area of transmission of another radio-frequency tag communication device.
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Accused Products
Abstract
A radio-frequency tag communication device permitting a radio-frequency tag communication system to have a sufficiently large area of communication, with a minimum required number of interrogators. The radio-frequency tag communication device includes a transmission control portion operable to control transmission of a transmitted signal, so as to prevent overlapping an area of communication of the radio-frequency tag communication device and an area of communication of another radio-frequency tag communication device, making it possible to maximize a spacing distance between the adjacent radio-frequency tag communication devices, and to effectively prevent concurrent receptions of the transmitted signals by the plurality of radio-frequency tags. Namely, the radio-frequency tag communication device permits the radio-frequency tag communication system to have a sufficiently large area of communication with a minimum required number of interrogators.
50 Citations
25 Claims
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1. A radio-frequency tag communication device arranged to transmit a transmitted signal toward radio-frequency tags, and to receive reply signals transmitted from the radio-frequency tags in response to the transmitted signals, for communication with the radio-frequency tags, said radio-frequency tag communication device comprising:
a transmission control portion operable to control transmission of said transmitted signal, so as to prevent overlapping of an area of communication of said radio-frequency tag communication device and an area of transmission of another radio-frequency tag communication device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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15. A radio-frequency tag detecting system comprising:
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a plurality of stationary radio-frequency tag communication devices which are located at respective predetermined positions and which are arranged to transmit transmitted signals toward a predetermined radio-frequency tag and to receive a reply signal transmitted from the radio-frequency tag, for communication with the radio-frequency tag;
a portable radio-frequency tag communication device which is arranged to transmit a transmitted signal toward said radio-frequency tag and to receive a reply signal transmitted from the radio-frequency tag, for detecting the radio-frequency tag located within areas of communication of said plurality of stationary radio-frequency tag communication devices; and
a transmission control portion operable to control transmission of said transmitted signals such that said plurality of stationary radio-frequency tag communication devices and said portable radio-frequency tag communication device transmit said transmitted signals at respective different timings. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
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Specification