Wireless Platform for Multi-Channel Analog Measurements

This paper describes wireless measurement platform, which uses inductive power and data transmission and provides up to four analog measurement channels. Platform is powered by inductive coupling using the 125 kHz magnetic field. Data transmission is realized by modulating the magnetic field. The platform has up to four 10-bit analog channels. The sample rate of the platform is 237 samples per second, which is divided between the used channels as needed. With 2.85 V supply voltage the measurement platform has power consumption less than 1.5 mW. Nevertheless the end application´s total power consumption depends on the measurement set-up. Except for the antenna coil, the measurement platform is made using the commercially available components. Main target application for the platform is implantable electrocardiogram (ECG) measurement. At this stage ECG measurements are done with one channel. Additional channels are available for example for other ECG channels, temperature or acceleration measurements