The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 03, 2012
Filed:
Sep. 20, 2007
Katsuyuki Kuramoto, Chigasaki, JP;
Katsuyuki Kuramoto, Chigasaki, JP;
Brother Kogyo Kabushiki Kaisha, Nagoya-shi, Aichi-ken, JP;
Abstract
A radio-frequency tag communication device including a receiver array antenna device for receiving a reply signal, a cancel-signal generating portion configured to generate a cancel signal for eliminating a leakage signal that is a part of a transmitted signal, which part is received by the receiver array antenna device, a cancel-signal control portion configured to control a phase and/or an amplitude of the cancel signal generated by the cancel-signal generating portion, and a received-signal combining portion configured to combine together received signals received by a plurality of antenna elements of the receiver array antenna device, to obtain a composite signal, and wherein the transmission of the transmitted signal and the reception of the received signals are concurrently controlled, and the cancel signal generated by the cancel-signal generating portion is applied to the received-signal combining portion, whereby the received signals and the cancel signal are combined together, so that a signal/noise ratio of a wave detector output upon demodulation of the composite signal is improved to increase the maximum distance of communication.