Figure 1
From: Feasibility of backscatter RFID systems on the human body
On-body RFID systems. The RFID reader is situated on the stomach of a female, while four RFID sensor tags are placed at various positions on the female’s body—on the right chest, on the middle of the back, on the left side of the head, and on the right wrist. The sensor tag on the back is represented by an orange circle. The investigated RFID systems are composed of custom-built monopole or patch antennas operating at 900 MHz or 2.45 GHz. Each antenna acts as both reader and tag antennas (reprinted from [20], Ⓒ2012 IEEE).