Development of Wireless Transducer for Real-Time Remote Patient Monitoring

A novel wireless transducer that uses analog-based technology at 2.4 GHz is presented in this letter. The transducer consists of an electrocardiography (ECG) detection circuit and a novel three-stage amplitude modulation transmitter that up-converts the ECG signal to a 2.4-GHz carrier frequency. To minimize the effects due to local oscillator leakage as well as the interference at the image frequency, the intermediate frequency is carefully selected, and a bandpass filter with a very sharp selectivity is designed. As demonstrated by the experimental results, the full-wave ECG signals can be successfully demodulated from the transmitted signal using the presented transducer. This enables the possibility of using analog-based technology for remote patient monitoring in real time.