| With the improvement of national living standards, the increasing rate of aging as well asthe social pressure, the morbidity and mortality of cardiovascular disease in our country areshowing a rising trend year by year. Therefore, it is a great importance to find earlycardiovascular disease and to obtain the situation of the disease for the cardiovasculardiseases prevention and treatment.At present, there are following common-used methods of collecting heart sound signals.Firstly, it is the cardiac auscultation system based on the traditional stethoscope, which isdirectly affected by the sensitivity of stethoscope, human hearing status, doctors’ clinicalexperience and auscultation technology, so the accuracy rate of auscultation is poor. Secondly,it is the heart sound acquisition system based on single channel digital stethoscope, recordingfunction of this system is better; because it’s useful to the heart sound analysis with digitalsignal processing techniques. However, it is not convenience to do multi-channel heart soundssignals acquisition. Thirdly, it is heart sounds collection system based on the four-channelBIOPAC and auscultation, which broke the single-lead auscultation system operationcumbersome, inefficient diagnostic limitations. This system is easier to be worn, and it has theanti-interference ability as well as visualization features. However, because of its bulk, it isdifficult and inconvenient to be carried and to be used in practice. Therefore, in team of easeusing, it is essential to develop a relatively portable four-channel PCG acquisition system,which is proposed in this thesis.A set of portable heart sound acquisition system is designed in this thesis, whichincluded the four-channel heart sound signal acquisition module and application softwarebased on the android mobile phone. The main studies were introduced in the followingseveral aspects.(1)The introduction of heart sounds and heart disease knowledge. From the perspective ofmedical science, this thesis introduced the generation and basic characteristics of heart soundand the composition of heart sound signals, and compared the several acquisition methods witheach other. From a practical point of view, the necessarty of studying heart soundssynchronous acquisition instrument based on android moble is introduced in this thesis.(2)The hardware design of four-channel heart sound synchronization acquisitioninstrument. The design of hardware included the analog circuit and embedded systemhardware. Hardware design mainly included power circuit, filter circuit, amplifying analogcircuit a trap circuit. In each module, the device and circuit structure were explained in detail.The Embedded hardware designed a system which is based on the S3C6410X processor, andintroduced Linux system migration and its characteristics. (3)The design based on S3C6410X of Wi-Fi hotspots. This part included the preparationof EP-N8508GS based Wi-Fi wireless network card driver transplantation, and relatedconfiguration files.(4)The software design of four-channel heart sound synchronous acquisition instrument.Software design is the research focus of this thesis. At first, the driver of S3C6410X of ADCwhich based on Linux and the server program to send data to mobile phones were desiged.Secondly, Android-based mobile terminal client program was designed completely; this partprimarily included the acceptance of the data, waveform displaying, data saveing, heart ratecalculation and display.(5)System testing. In order to verify the system whether can complete the desired goals,several testings were carried out, they were data acquisition tested, waveform display tested,heart rate display tested, file upload tested. It improved the design of the whole system bytesting.In view of the cardiovascular disease prevention, an efficient, convenient and cheap heartsound acquisition system was developed in this thesis based on android mobile phole platform.The system sends the heart sound signals to mobile phone through Wi-Fi wireless network.Then the data was processed in the mobile terminal, the waveforms were displayed on thescreen synchronization and the heart rate was calculates, at last the data can be saved andtransfered. It achieved the design purpose of synchronization acquisition for four-channel heartauscultation. At the same time, it is of great significance to collect the lung sound signals andbreathing of human physiological signals and so on. |
PDF Full Text Request