Design Of Multi-Physical Signal Acquisition And Intelligent Analysis System Based On FPGA

Health is an important issue related to both national economy and people's livelihood.In recent years,there is an emergence for the medical instruments that acquire physiological signals non-invasively.Designing for different situations,they possess kinds of different features.Nevertheless,deficiencies still exist for the instruments:lacking general modular expansion ability,portability shortage,and intelligent analysis capability insufficiency.Therefore,it could make a different if any expandable,portable and intelligent instruments should be developed.We did the following researches in this thesis:Firstly,the multi-physiological-signal acquisition terminal has been designed and implemented through which both electrophysiological(including Electrocardiography,Electromyography etc.)and non-electrophysiological signals(including Photoplethysmography,Electrodermal Activity etc.)could be collected.The chip ADS1298(Texas Instruments,America)was utilized as the analog front-end(AFE)for electrophysiological signals,the chip ADS101E08S(Texas Instruments,America)for general signals,the chip AFE4400(Texas Instruments,America)for photoplethys-mography,The communication as well as data exchange was achieved by means of USB and the chip CY7C68013A(Cypress,America)was used as the controller.Meanwhile,the designing of both AFE circuit and the FPGA logic were implemented to enable the signal acquisition.Thus,this instrument could serve as an independent acquisition instrument.As a matter of fact,the instrument has passed the safety tests under GB9706.1 standard conducted by Zhejiang Institute of Medical Device Supervision and Testing.The examination result showed that the instrument possessed a leakage current less than 0.001mA and could withstand the test voltage of up to 1500V in both the normal working temperature and humid pretreatment test.Secondly,the intelligent analysis terminal has been designed further using the programable chip ZYNQ based on data acquisition function.It helped improve the flexibility as well as the user experience and made it possible for on-board algorithm verification for multi-physical signal acqui-sition terminal.With the help of PetaLinux,the embedded Linux was customized and transplanted in the terminal in order to implement complex task scheduling.In addition,a character device driver of DMA was designed to enable the bio-direction data transfer between programmable logic and processing system.A support vector machine(SVM)classifier was designed to verify the al-gorithm on the terminal.Finally,a public character recognition data-set was utilized to assess the performance of the SVM.As what demonstrated in the system function and performance test,the multi-physiological signal acquisition terminal was stable in both on-board SPI and USB communication,and could be used as a preliminary physiological signal collector.And the pass of electrical safety tests made the terminal guaranteed in reliability and safety.The DMA transmission test verified data acquiring function of the intelligent analysis terminal.Further,the performance of support vector machine in the character recognition data-set help prove and verify the on-board algorithm's effectiveness of the terminal.This research could serve as a data acquisition and prototype development platform for clinical medicine,psychology and other fields.Simultaneously,it could be a guiding reference for the development of similar instrument prototype on specific occasions.