Wearable Wireless ECG Monitoring System Design

ECG is an important parameter in the medical health,and human health is reflected by that,which is the important basis in the diagnosis of cardiovascular emergency disease.For people with the needs about real-time ECG,wearable ECG monitoring equipment will be a good choice.Based on this,wearable technology is used in this paper,and the ECG monitoring system of the combination between the ECG monitoring and clothing is designed,and the ECG signals of the users can be collected in real time.Firstly,the overall structure of the wearable wireless ECG monitoring system is designed,which is based on the electrode of the fabrics.In this structure,the production of the apparel clothing and the design of the hardware and software of the ECG monitoring system are included.The production of the clothes and fabric electrode and the stitching of the wire are included in the production of the wear garment.The fabric electrode is made by the fiber which is a processed silver chloride coated silver,and that is sewed in the following three parts,the left chest handle,the right chest handle and the left lower abdomen,and which is connected to the button interface that is jointed with the ECG monitoring system through the inner stitched wire.Secondly,the system hardware circuit is designed,and in this design,the signal acquisition and signal processing are concluded.The signal is mainly extracted by the analog front end acquisition circuit of the system correctly,and which is the key part.According to the characteristics of the small and exquisite of the wearable devices,the AD8232 chip of the ADI company is used as the analog front-end,and the design of the analog front-end is smaller than the front-end acquisition circuit which is composed by the average precision instrumentation amplifier.And then the right leg drive circuit,high pass and low pass filter circuit are designed,and the ECG information is extracted successfully.The low-power processing STM32F103CBT6 of the ST company is used for the control core by the signal processing circuit.And then through the extension circuit,the A/D conversion of the analog signals,software filtering,display,storage and distribution are completed.Then,the software part of the ECG monitoring system is wrote.In this part,MDK is used for the development tools,C language is used for programming,all kinds of function are completed through the way that all kinds of subprogram modules are called by main program.MATLAB is firstly used to verify the kalman filtering algorithm,the results show that the noise and interference are suppressed.And then the ECG signal graphic is displayed by the detachable LCD,in order to process the data furthermore,the bluetooth function is designed to connect wireless terminal.Finally,the prototype system is developed,and some corresponding test is processed based on this.The design requirement of the system is met well by the prototype system,the waveform of the monitored ECG signal is displayed obviously,and in the same time,all the other functions are normal,the performance is good.