听觉诱发脑干反应检测仪的设计

发布时间：2019-03-05 09:34

【摘要】：听觉诱发脑干反应信号是产生于听神经，表现在头顶与乳突之间的脑电信号，通过对听力诱发脑干反应信号的检测不仅能够判断人耳听力功能的正常与否而且还能够有效的定位听力功能的病变部位。目前国内的听觉诱发脑干信号检测设备市场基本被国外公司垄断，而且价格昂贵。所以本文设计一款性价比比较高的听觉诱发脑干信号检测仪。本文在深入研究了听觉诱发脑干反应信号特点的基础上，，针对听觉诱发脑干反应信号微弱，突变性强造成信号提取困难的特点，设计高输入阻抗、低噪声的前置放大电路，并且采用中位值平均滤波对提取的脑电信号做前期去噪，利用DB系小波的局部化能力强、coif系小波较强的高低频率划分能力的特点，结合DB6小波与coif3小波对听力诱发脑电信号进行后期去噪，利用余弦求和算法对听觉诱发脑干反应信号进行时域的特征提取。在硬件电路设计上，诱发刺激声发生单元包括数模转换电路、音频放大电路和选择发声探头，信号处理采集单元包括脑电电极、前置放大电路、二级放大电路、三级滤波电路、主放大电路，信号采集电路，此外还具有通信单元、数据存储单元、时钟电路单元、电源单元、打印单元等。本文设计的听觉诱发脑干反应检测仪可以与上位机连接使用。利用仪器进行实验验证设计的可行性。
[Abstract]:The auditory evoked brainstem response (brainstem response) is an electrical signal of the brain between the head of the head and the mastoid, which is produced by the auditory nerve. The detection of auditory evoked brainstem response signal can not only judge the normal or not of human ear hearing function, but also can effectively locate the lesion location of hearing function. At present, the market of auditory evoked brainstem signal detection equipment is monopolized by foreign companies, and the price is expensive. Therefore, this paper designs a high cost-effective auditory evoked brainstem signal detector. Based on the in-depth study of the characteristics of auditory evoked brainstem response signal, a preamplifier circuit with high input impedance and low noise is designed in this paper, aiming at the characteristics of weak auditory evoked brainstem response signal and the difficulty of signal extraction caused by the strong mutagenicity of auditory evoked brainstem response signal. The median average filter is used to Denoise the extracted EEG signal in the early stage, and the characteristics of the high and low frequency partition ability of the DB wavelet and coifwavelet are used, which are strong in localization ability and coif wavelet in high and low frequency. Combined with DB6 wavelet and Coif3 wavelet, the auditory evoked EEG signal was de-noised at the later stage. The cosine summation algorithm was used to extract the features of the auditory evoked brainstem response signal in time domain. In the hardware circuit design, the evoked stimulation sound generating unit includes the digital-analog conversion circuit, the audio amplifying circuit and the selective sounding probe. The signal processing acquisition unit includes the EEG electrode, the preamplifier circuit, the second-stage amplifier circuit and the three-stage filter circuit. Main amplifier circuit, signal acquisition circuit, communication unit, data storage unit, clock circuit unit, power supply unit, printing unit, etc. The auditory evoked brainstem response detector designed in this paper can be connected with the upper computer. The feasibility of the design is verified by experiment with the instrument.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN911.7;R318.04

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