Wireless Logger for Biosignals

This work proposed a novel 4-channel wireless data logger that uses electromyography (EMG), electrocardiograph (EKG), and accelerometer transducers for field measurements of biosignals. The logger, which weighs 102 g (including the battery), continually acquires 4-channel 16-bit analog signals at 1000 Hz/channel. The acquired data are saved on a microSD memory card for subsequent analysis. The logger utilizes a ZigBee transceiver module that transmits acquired data to a remote receiver. The logger can run for over 6 consecutive hours at full load when powered by two 860 mAh batteries. The remote receiver unit, connected to a PC or laptop via a USB interface, was controlled by Window-based monitoring software for communicating with the logger. The monitoring software programmed by Borland C++ Builder operated the logger and monitored real-time data sent from the logger. Three laboratory experimentsand two prolonged field tests were performed to test logger feasibility. The experimental results demonstrate that the system is reliable and feasible for field measurements of biosignals for a prolonged period.