A modified bow-tie antenna for contact-based heartbeats detection applications

In this communication, a modified bow-tie antenna is proposed and its impedance characteristics are investigated both numerically and experimentally for body-contact heartbeat detection applications. The proposed antenna consists of a bow-tie structure, a pair of T-shaped loading and stubs. The antenna parameters and body effects on the impedance bandwidth of the antenna are presented and discussed. The antenna has a bandwidth of 92% for voltage standing wave ratio (VSWR) less than 2. By considering the electrical properties of the human tissue, the antenna bandwidth is highly enhanced because the penetration electromagnetic wave is absorbed by the human body. Such a wide band antenna can be used in body-contact radar for heartbeat detection to improve the microwave imaging resolution.