Abstract
Radio frequency (RF) devices such as antennas play a crucial role in implantable and ingestible medical devices (IMDs) by enabling wireless communication, energy harvesting, and localization links between transmitter (Tx) and receiver (Rx). Implantable and ingestible medical devices (IMDs) have transformed modern healthcare by enabling real-time monitoring and improving treatment outcomes. Radio frequency (RF) sensor antennas are key components in these devices and are widely used in biomedical applications for early diagnosis, treatment, and continuous health monitoring. RF-enabled IMDs monitor vital parameters such as temperature, blood pressure, glucose levels, oxygen saturation, pH, and blood composition. These antennas also support devices like pacemakers and defibrillators in managing cardiac conditions. In addition to human healthcare, they are applied in animal health monitoring and veterinary diagnostics. Implanted antennas detect physiological changes and wirelessly transmit data to external processing units, allowing real-time access for medical experts. This integration of RF sensing in IMDs enhances the ability to detect diseases early and deliver timely interventions, making them essential tools in both clinical and remote healthcare settings. This article presents two RF sensor antennas—FR-4 integrated (Ant-1) and miniaturized helical (Ant-2)—designed for implantable and ingestible medical devices, particularly in veterinary applications, operating in the 400–500 MHz range. Ant-1 is fabricated on an FR-4 substrate (51×28×1.6 mm³, ℇr = 4.4, tanδ = 0.002), resonating at 434 MHz with a bandwidth of 32.13 MHz and a total gain of approximately –36.92 dB without the phantom model and with the phantom in an acceptable range. Ant-2 is a miniaturized normal-mode helical antenna made of 0.9 mm diameter copper wire, also resonating at 434 MHz and both antennas integrate a surface acoustic wave (SAW) sensor to enhance wireless sensing. SAW sensors utilize acoustic waves on piezoelectric surfaces to detect parameters like temperature, pressure, strain, and displacement, enabling real-time, wireless physiological monitoring in biomedical applications.
References
- Omboni, Stefano, Raj S. Padwal, Tourkiah Alessa, Béla Benczúr, Beverly B. Green, Ilona Hubbard, Kazuomi Kario et al. "The worldwide impact of telemedicine during COVID-19: current evidence and recommendations for the future." Connected health 1 (2022): 7.
- Khan, Tayyaba, MuhibUr Rahman, Adeel Akram, Yasar Amin, and Hannu Tenhunen. "A low-cost CPW-fed multiband frequency reconfigurable antenna for wireless applications." Electronics 8, no. 8 (2019): 900.
- Riaz, Sharjeel, Mansoor Khan, Umer Javed, and Xiongwen Zhao. "A miniaturized frequency reconfigurable patch antenna for IoT applications." Wireless Personal Communications (2022): 1-11.
- Kokkonen, Mikko, Mikko Nelo, Henrikki Liimatainen, Jonne Ukkola, Nuutti Tervo, Sami Myllymäki, Jari Juuti, and Heli Jantunen. "Wood-based composite materials for ultralight lens antennas in 6G systems." Materials Advances 3, no. 3 (2022): 1687-1694.
- Kiourti, Asimina, and Konstantina S. Nikita. "A review of in-body biotelemetry devices: Implantables, ingestibles, and injectables." IEEE Transactions on Biomedical Engineering 64, no. 7 (2017): 1422-1430.
- Gurain, G. "Miniature microwave biosensors." IEEE Microw. Mag 16, no. 4 (2015): 71-86.
- Pang, Changhyun, Chanseok Lee, and Kahp‐Yang Suh. "Recent advances in flexible sensors for wearable and implantable devices." Journal of Applied Polymer Science 130, no. 3 (2013): 1429-1441.
- Zheng, Ya-Li, Xiao-Rong Ding, Carmen Chung Yan Poon, Benny Ping Lai Lo, Heye Zhang, Xiao-Lin Zhou, Guang-Zhong Yang, Ni Zhao, and Yuan-Ting Zhang. "Unobtrusive sensing and wearable devices for health informatics." IEEE transactions on biomedical engineering 61, no. 5 (2014): 1538-1554.
- Govindan, Thennarasi, Sandeep Kumar Palaniswamy, Malathi Kanagasabai, Sachin Kumar, Rajesh Agarwal, Rajkishor Kumar, and Damodar Panigrahy. "Design and analysis of a conformal mimo ingestible bolus sensor antenna for wireless capsule endoscopy for animal husbandry." IEEE Sensors Journal 23, no. 22 (2023): 28150-28158.
- Benaissa, Said, Denys Nikolayev, Günter Vermeeren, Kenneth Deprez, Jasper Goethals, Bart Sonck, Frank AM Tuyttens, Luc Martens, David Plets, and Wout Joseph. "Design and experimental validation of a multiband conformal patch antenna for animal-ingestible bolus applications." IEEE Transactions on Antennas and Propagation 71, no. 8 (2023): 6365-6377.
- Saadat, Waqar, Sumit A. Raurale, Gareth A. Conway, and John McAllister. "Wearable antennas for human identification at 2.45 GHz." IEEE Transactions on Antennas and Propagation 70, no. 1 (2021): 17-26.
- Sato, Shigeru, Hitoshi Mizuguchi, Kazunori Ito, Kentaro Ikuta, Atushi Kimura, and Keiji Okada. "Development and testing of a radio transmission pH measurement system for continuous monitoring of ruminal pH in cows." Preventive veterinary medicine 103, no. 4 (2012): 274-279.
- Eihvalde, Indra, Daina Kairisa, and Ilga Sematovica. "Long-term continuous monitoring of ruminal ph and temperature for dairy cows with indwelling and wireless data transmitting unit." Parameters 3555, no. 4525 (2016): 4829.
- Gallagher, M. W., B. C. Santos, and D. C. Malocha. "Wireless wideband SAW sensor-antenna design." In 2010 IEEE International Frequency Control Symposium, IEEE, (2010): 291-296.
- Kumar, Rupesh, and Nirupama Mandal. "SAW Sensor Basics on Material, Antenna, and Applications: A Review." IEEE Sensors Journal 24, no. 5 (2024): 5713-5731.
- Saroj, Abhishek Kumar, and Jamshed Aslam Ansari. "A reconfigurable multiband rhombic shaped microstrip antenna for wireless smart applications." International Journal of RF and Microwave Computer‐Aided Engineering 30, no. 10 (2020): e22378.
- Das, Soumyadeep, and Debasis Mitra. "A compact wideband flexible implantable slot antenna design with enhanced gain." IEEE Transactions on Antennas and Propagation 66, no. 8 (2018): 4309-4314.
- Lee, Chien‐Ming, Tzong‐Chee Yo, Fu‐Jhuan Huang, and Ching‐Hsing Luo. "Bandwidth enhancement of planar inverted‐F antenna for implantable biotelemetry." Microwave and Optical Technology Letters 51, no. 3 (2009): 749-752.
- International Commission on Non-Ionizing Radiation Protection. "Guidelines for limiting exposure to electromagnetic fields (100 kHz to 300 GHz)." Health physics 118, no. 5 (2020): 483-524.
- Chow, Eric Y., Chin-Lung Yang, and Pedro P. Irazoqui. "Wireless powering and propagation of radio frequencies through tissue." In Wireless Power Transfer, River Publishers, (2022): 301-335.
- Kiourti, Asimina, and Konstantina S. Nikita. "A review of in-body biotelemetry devices: Implantables, ingestibles, and injectables." IEEE Transactions on Biomedical Engineering 64, no. 7 (2017): 1422-1430.
