Takashi Nakajima’s research while affiliated with Chiba University and other places

Recently, Radio Frequency Identification (RFID) systems have been widely developed. The wristband type RFID tag is one of the applications for personal identification. In this case, since the RFID antenna is in the vicinity of a human, the human body affects the antenna characteristics. Therefore, the analyses of the performances of the RFID antenna are required. In this paper, the antenna inside the wristband was numerically analyzed and measured using the layer structural arm model. As a result, characteristics of the antenna were clarified.

In recent years, RFID (radio frequency identification) systems are widely developed. There are many types of RFID tag and each tag is used for suitable application. The wristband type RFID tag is one of the applications for personal identification. In case an RFID tag is used close to a human, the human body affects the characteristics of the RFID antenna. In this paper, a reflector-loaded antenna that placed close to the human body has been calculated in order to analyze the operation of the wristband type RFID antenna. Moreover, the antenna radiation patterns and input characteristics were measured by use of a biological tissue-equivalent solid phantom. As a result, characteristics of the antenna were clarified. In addition, the effect on the antenna characteristics was verified when the space between the arm and the wristband was changed.