Antenna Design for Wireless Transmission of Ocular Pressure Signal and Injection Fluid Empty Monitoring

• Main Authors: Ssu-HanTing, 丁嗣翰
• Other Authors: Ching-Hsing Luo
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/6a7s94

博士 === 國立成功大學 === 電機工程學系 === 105 === Recently, wireless biotelemetry system (WBS) are widely applied to acquire physiological signals for healthcare monitoring applications. In order to wear a wireless sensing device, even implant it into human body, the limitations of environment and size would cause great influences on antenna design in or on human body. As reported in published articles, the size of implantable antenna are around 150 to 1300 mm^3, but the antenna gains are only about -38 to -25 dBi. The poor radiation efficiency for those design would increase the loading and risks of RF system design. In the wearable device research, rarely referred to which antenna architecture Suitable to be used, the impact on the human body was also lack of discussion. For the implantable and wearable antenna is limited by the human body environmental impact at design part, and it with human tissue will reduce the antenna radiation efficiency. In previous implantable and wearable antenna research, the most of antenna architecture are used PIFA type, but this one has some shortcomings such as narrow bandwidth and poor radiation efficiency when the radiation arm is close to ground plane. In order to improve the bandwidth and efficiency, in this proposed loop type antenna is used in the design to promote antenna bandwidth and radiation efficiency, and also used the new material (thin-film poly-para-xylylene) is well to reduce antenna size. Now in view of the shortage of medical manpower resources, how to effectively monitor a physiological signal will be worth thinking about the direction. In the past, it need nurses to recheck, in order to solve this annoying problem we also proposed the new antenna design for injection fluid empty monitoring. We use the injection fluid as the antenna base to design it, and we also used RFID system detection the warning signal. When injection fluid reduce to 12.6 ml antenna resonance mode will shift to 915 MHz, at this moment system will sent the warning massage to nursing station, by this system to solve the problem of medical understaffed. The measured results indicate that the proposed the half wave wearable antenna can cover 2.4 (2.4-2.4835 GHz) and 5G (5.15-5.85 GHz) two ISM bands operation. Using this material it can reduce antenna size to 38 mm^3, antenna average gain and efficiency at 2.4 and 5 GHz can achieve -4.8,-3.7 dB and 10.2 %, 20.5 %. Antenna simulated SAR value was less than FCC 1-g SAR specification (1.6W/Kg) at 2.4 and 5 GHz. At injection fluid empty monitoring antenna design we also verification the warning accuracy by integration the RFID system. Using these measured results we can get the mean (μ) and standard deviation (σ). By normal probability distribution calculation we can get the warning interval. The warning internal is 12.6 to 7.3 ml, and in this internal the accuracy of the reported up to 96%. This accurate warning system can effective to notice nursing station, by this way it can reduce the work of nursing staff. According to the results of measurement, it reveals the proposed antenna suitable for the design of monitoring applications.