RFID tag wide bandwidth logarithmic spiral antenna method and system

摘要

Radio wave system recognition (RFID) the tag antenna system, has, the logarithm spiral antenna of two arms of plane surface with the factor of small form for the appropriateness. The foil of the conductivity which is stretched on the baseplate or, two arms of the copper which is etched exist. The said two arms from the center extending are present with logarithm style facing toward outside. As for the arm of the aforementioned two it is identical mutually being able to turn just 180 degrees mutually, but in inside plane surface, it is. In addition the aforementioned arm, those directing outside, as it extends, being proportionate to width, it spreads gradually, but width of both arms is equal mutually in the distance of optional given from the aforementioned center, at the same time, ideally, is equal to the interval between the said arms. Impedance matching network receives the RF signal which is received by those two spiral antennas offers that RF signal to the electronic circuit. The said electronic circuit, in order to form the DC signal which charges the condenser, rectifies that signal, makes increase. As the aforementioned plane surface antenna to construct on the same baseplate it is possible the aforementioned electronic circuit, but, as for the said circuit, it is constructed on the 2nd baseplate which is mounted to ideal, you can do to the antenna which supports the baseplate appropriate electric connection.