Galvanical Coupling for Data Transmission through the Human Body

Abstract

Using the human body as a transmission medium for electrical signals becomes a novel data communication technique in biomedical monitoring systems. Galvanical coupling is a promising approach for wireless intra-body data transmission between sensors. In this work, special attention is given to the coupling of the current into the human body. Safety requirements have to be fulfilled and optimal signal coupling is requested. Therefore, different electrodes are compared. A test system offers up to 1 mA contact current modulated in the frequency range of 10 kHz to 1 MHz. The injected current is 20 times below the maximum allowed contact current and more than 50 times below nerve stimulation. Such a low-current approach enables data communication that is more energy-saving than other wireless technologies