Measurement of human body communication transmission characteristics at 20 MHz

Transmission characteristics of human body communication at 20 MHz were measured by using a battery operated transmitter and a receiver to eliminate undesirable coupling between cables for measurement or power supply. Received signal strength indication (RSSI) was recorded on the memory of the receiver and retrieved afterward. Transmission from chest to wrist was measured, assuming a transmission of ECG signal from chest to a wearable device worn on the wrist. RSSI values were compared for different contact conditions. The largest signal was obtained when the signal electrode of the receiver was in contact with the human body and the ground electrode was floating.