Summary: | 碩士 === 國立交通大學 === 電控工程研究所 === 103 === In order to achieve long-term intraocular pressure (IOP) monitoring, this thesis presents a wireless readout system based on radio frequency identification (RFID) technology used to readout contact lens IOP sensor device. A digital baseband circuit, receive antenna and transmit antenna has been designed and fabricated to implement a pre-testing wireless IOP sensing tag.
Considering the restriction on antenna size which is limited by contact lens, this thesis used 860 ~ 960 MHz as communication frequency band, designed a single-loop like antenna using inductive coupling to obtain higher energy transmission efficiency in near field under the conditions that the size of antenna is much smaller than the wavelength.
The proposed sensing tag can perform 2 cm wireless sensing with 12.6 dBm RF power, and reached the maximum sensing distance of 7 cm under 30 dBm, which has met the requirement of our application. Furthermore, a next generation receive antenna has been designed and simulated, according to the pre-testing result, a 18.2 dBm RF power is needed to accomplish wireless sensing at distance of 2 cm.
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