Research On Reconfigurable Antennas And NFC Technology For Human Body Communication

NFC technology is a new communication technology,which is mainly used for shortrange wireless signal transmission.NFC antenna is a common antenna in radio frequency identification technology,and its working frequency is 13.56 MHz.Combined with RF circuit,the antenna can transmit and receive information stored in RF circuit chip.With the development of modern biomedicine,NFC technology is gradually used in medical wearable devices,which requires the antenna to have good stability,in order to accurately read data.In this paper,a double-layer NFC antenna is proposed and compared with the traditional singlelayer NFC antenna to judge their stability.The relationship between the inductance of NFC antenna and the antenna parameters is also studied.It is found that the inductance of NFC antenna changes with the size of the antenna coil,and the single-layer NFC antenna is more stable than the double-layer NFC antenna.With the development of modern intelligent technology,human communication devices emerge in endlessly,and the requirements of wearable technology are also higher and higher.In order to achieve multi-function,the importance of reconfigurable technology cannot be ignored.In this paper,two kinds of reconfigurable antennas are proposed.They are similar in structure,they are composed of a circular patch,a ring patch and a slot patch,but their working principles are different.The two reconfigurable antennas can achieve directional radiation mode of external communication and omni-directional radiation mode of body surface communication at 2.45 GHz frequency,and can achieve internal communication at403 mhz frequency,and both can achieve function switching.