Non-invasive synchronized spatially high-resolution wireless body area network

Abstract

Wireless body sensor networks consisting of EEG, ECG, EMG and acceleration sensors provide assistance to the researchers in cognitive physiology and clinical research as well as in neurophysiology. The data fusion of the electrical activities of muscle structures, e.g. facial muscles, heart and brain combined with the movement data of patients helps to detect nocturnal epileptic seizure in home care application. A mobile, flexible, densely configurable distributed body area network featuring wireless data transmission and a wired time synchronization technique was designed and realized in this work Signal conditioning of each of sensor systems was realized depending on their signal strength and frequency bandwidth. Moreover, synchronization between each of the nodes was achieved with the help of wired USART (universal synchronous/asynchronous receiver/transmitter). All measurement units follow the same synchronization protocol, which is controlled by a master unit. The ExG-system can sample bio-potentials from 125 Hz up to 1000 Hz and it exhibits 1.445 μν peak-to-peak system noise between 0.1 Hz and 500 Hz and can send data with incorporated Wi-Fi module in it to a basis station at a maximum data speed of 1.45 Mbps. A 3-4 cm spatial resolution can be achieved for high-dense EEG during a complete 256 channel deployment.