Small antennas of active RFID tags have low radiation efficiency because of its smaller size compared with wave
length and loss materials such as surface mounted elements. Q-factor method is well known to calculate radiation efficiency of
antennas and the method needs accurate value of Q-factor. We investigate, in this study, the method to calculate precise Q-factor
from impedance characteristics.
(英)
Small antennas of active RFID tags have low radiation efficiency because of its smaller size compared with wave
length and loss materials such as surface mounted elements. Q-factor method is well known to calculate radiation efficiency of
antennas and the method needs accurate value of Q-factor. We investigate, in this study, the method to calculate precise Q-factor
from impedance characteristics.