Research On Biological Signal Acquisition Terminal For Internet Of Things

With the intensification of the aging society, environmental issues have becomingincreasingly prominent; people pay more and more attention to their own health information,so the demand for their own biological signals intelligence collection and monitoring will bein explosive growth. However, conventional biological signal acquisition devices (ECG, bloodpressure meter, etc.), its collection efficiency is low, degree is not enough, witch already cannot meet people’s needs. With the development of the Internet of Things, the Internet ofThings technology will be applied to biological signals (ECG, EEG, blood pressure signals,etc.) for intelligent collection and monitoring systems, making the collection, management,analysis and monitoring more efficient, convenient and fast. It just fit the demand of peoplefor efficient, low-cost health information management systems.This paper studies the biological signals acquisition system based on the Internet ofthings, using the standards of networking nodes to design biological signal acquisitiondevices. Focuses on the key issues of the biological signal’s acquisition and transmission,such as signal amplification, noise reduction, digitization, storage, transmission program andother issues, and take an example for ECG, I designed and implemented ECG signalacquisition terminal based on the internet of things.In the signal acquisition process, in order to solve the biological signals amplification,noise reduction, digitization, storage, and other issues, this article introduced instrumentationamplifier and multi-stage amplification technique to amplify weak signals; this paperssummarized a set of noise removal strategies for biological signals to address the problem ofsignal de-noising; designed SD card data storage solutions for local data storage, Andapplied these solutions to ECG collection terminal. Designed and implemented a single-leadECG acquisition devices and12-lead ECG acquisition terminal, in these devices, I designedthe two-stage amplifier circuit to amplify ECG signal. Designed low-pass filter and shieldedcircuits to eliminate high frequency noise, band-stop filter are designed to eliminate frequencyinterference. Using a dedicated chip ADS1298(ECG acquisition IC) for ECG digitization.ECG data are written to the SD card in the form of file, I alse designed data frame format anddata packet format to ensure efficient storage. Currently, these two acquisition devices havebeen used in the laboratory for a year, the data collected by them is accurate and reliable.In data transmission, in order to solve the problem of internal speed matching betweeneach modules and the CPU in the system, this paper presents the internal data transmissionbalancing strategy to solve the conflict between the real-time and multi-tasking in CPU. Tosolve the problem of wireless data transmission, this paper studied a variety of wirelesstransmission protocol, designed and implemented a3G transmission program witch suitablefor biological signals. In order to solve the problem of packet loss during transmission, thispaper presents data redundancy strategy, greatly reducing the dropout rate. In this article, based on3G, a12-lead ECG acquisition terminal are realized to achieve real-timeacquisition and real-time transmission for ECG, using this equipment,we have been ableto collect and monitor remote ECG signals.