Optimized Substrate Integrated Waveguide (SIW) Antenna for Wearable Health Monitoring Applications

Around 50 million people in the world are affected by chronic seizures and epilepsy. Seizures are usually diagnosed by CT scans, MRI scans, EEGs, and blood tests. However, there is a need for devices that help people to detect and receive alerts before the onset of a seizure episode. This paper addresses the need to design a seizure detection device that works on the principle of changing muscle permittivity. As chronic seizures can be life-threatening, there is a need for devices that detect seizures before their onset, to help a person take precautionary measures. Though there are a few devices that work for this application, there is always room for improvement and innovation. Therefore, we have proposed a novel microstrip patch antenna that acts as a miniaturised biosensor. One of the major symptoms of seizure is the change in muscle stiffness. Considering this factor, our antenna is designed to detect the change in the permittivity caused due to the change in muscle tension which is reflected through the S parameter graph that gives us the information to detect a seizure attack beforehand. The return loss of the antenna is improved -27.596 dB by introducing the concept of substrate integrated waveguides. The antenna will be integrated into an embedded system design to enable it to function as a wearable device. Also, the SAR properties are analysed and optimized as per the FCC standards as it would be modelled as a wearable device. The antenna has been designed, simulated, and analysed using the ANSYS HFSS tool. Further, a comparative study on the various patch shapes, substrate materials, and SIWs was also made using ANSYS HFSS.