The Research And Realization Of Key Technology Of New Portable ECG Monitor Based On ’Electronic Skin’

As people’s living standards improves, cardiovascular disease (CVD) has becomeone of the major diseases that seriously threatens people’s health and life.Thecardiovasculardiseases are often sudden, unforeseen and highly risky.Electrocardiogram(ECG) is a main method for cardiovascular diseases diagnosis.Therefore, the development of a long-term, accurate and real-time portable ECGmonitor aiming to sample long-time ECG signal and detect the movements of patientsprecisely and exactly,plays an important role in preventing and curing CVD at earlystage and thus decreasing cardiac mortality and morbidity rates.At present, the extraction of ECG signal is still key technology for the research ofthe portable ECG monitor. Long-term, continual, real-time and remote monitoring isnecessary for home cardiac care, however, there are some disadvantages of the ECGmonitor on the market. Based on the actual demand of portable ECG monitor, a newECG signal extraction approach is proposed,which is able to detect ECG effectivelywhile being attached to clothes. It cancels the connecting wire between the electrodeand device, letting the patients move freely and feel comfortable.In this paper, we designed a contactless ECG and respiratory signal capture system.This system consists of two parts: sensor circuit and read-out circuit.Firstly, accordingto the ECG equivalent dipole model，a new electrode has been designed which putsrecord, reference and ground electrode together and also electrode leads are cancelled.Then,a new contactless ECG measuring method to sense ECG signals by varactors ispresented. Similar with instrumental amplifier, the total sensor circuit is a oscillator,which can amplify differential signals and restrain common signals. A skin-like flexiblecircuit membrane can be designed by ‘electric skin’ technology, which consists of‘cat-eye’ electrode and sensor circuit. It can be pasted on the skin by atmospherepressure with no fixation in the traditional way.Besides,the circuit can measurerespiration signal. Finally,HFSS software is used in simulation of planar spiral inductor.The electro-physiological signals can be transmitted wirelessly over resonancingcoupling coils.The read-out circuit receives the modulated signal and demodulates it bythe phase detecting method. The portable receiver can transmit signals to the remoteinformation processing platform over GPRS and ECG and sleeping respiration can bemonitored through corrleative calculation.