| Evoked Potentials(EP),as one kind of typical bioelectrical signal,which contains a large number of physiological and pathological information.Study the human body in the condition of normal function and changes in the disease process induced EP,and thus has important implications for basic physiological research and clinical diagnosis. EP acquisition system is the main tool to obtain induced EP, its importance is particularly prominent.Evoked eeg often submerged in routine EEG and non-stationary signal in strong noise, it is characterized by weak signal strength, low frequency and low anti-jamming ability, Therefore, how to effectively improve the accuracy of the EP acquisition, the focus is EP system design.Based on the analysis of domestic and foreign the current situation and development trend of EP research,first, this thesis designed a new kind of EP stimulator model,it is precisely controlled by a microcontroller, can produce a constant current pulses to stimulate the human body.Then a sample selection algorithm which needs no support of an external trigger source is presented in this thesis to overcome the shortcomings of the traditional EP acquisition system,it is a large degree of simplifying the hardware circuit, cost savings.Finally the thesis designs acquisition hardware system,made of EP can be collected,and this system under LabVIEW development platform bears the function of data reading, diagnosis, analysis and results displaying.Through experimental research for many times, this design can effectively extract the EP characteristics, study the different stimulation voltage and frequency of stimulation on EP characteristics influence,to improve the efficiency of diagnosis.This research provides an effective method for the rehabilitation and treatment of neurological diseases. |
