Human physiological signal acquisition device with adaptive industrial frequency noise suppression

Abstract

The invention relates to a human physiological signal acquisition device with adaptive industrial frequency noise suppression. After signals are acquired by a movable electrode and a reference electrode in the human physiological signal acquisition device provided by the invention, the signals are input to an instrument operational amplification circuit to realize amplification of differential mode signals and suppression of common mode signals; then, the signals are output to an anti-aliasing filter circuit to filter out interference of high-frequency noise; then analog signals are convertedinto digital signals by using an analog-to-digital conversion circuit; and the function of a digital processor is to control the analog-to-digital conversion circuit to convert analog signals into digital signals, read the converted digital signals at the same time, then process the digital signals such as channel identification and data splicing, then send the processed data to a microprocessor,and simultaneously send the processed data to a PC through a data transmission circuit to complete the works of data analysis, storage and the like. The human physiological signal acquisition device provided by the invention can automatically adjust the degree to which a circuit suppresses industrial frequency noise according to changes of the industrial frequency noise in different environments,and realize dynamic industrial frequency noise suppression.

Description

technical field [0001] The invention relates to the technical field of human physiological signal acquisition, in particular to a human physiological signal acquisition device with adaptive power frequency noise suppression. Background technique [0002] When collecting human physiological signals, the biggest noise interference that the acquisition equipment faces is the interference of 50 / 60Hz power frequency noise, and many useful signals such as EEG and EMG contain power frequency noise. Therefore, it is necessary to collect and send human physiological signals, which can not only suppress the interference of power frequency noise, but also retain the original signal to the greatest extent. [0003] Usually, the measure taken by acquisition equipment to suppress power frequency noise is to add a 50Hz filter circuit (generally requires a fourth order) to the circuit, and at the same time use the right leg drive technology to further suppress power frequency noise. This m...

AI Technical Summary

Problems solved by technology

But there are also some problems in this aspect: on the one hand, the 50Hz filter circuit increases the circuit volume and cost, and the circuit itself requires more resistors, capacitors and other devices, which is easy to generate new noise sources; on the other hand, the right leg drive circuit. The magnification is determined based on experience. Generally, the acceptable magnification is between 40 and 200 times. This circuit may be able to effectively suppress power frequency noise in an environment, but the environment changes and the amplitude of power frequency noise changes. , the inhibition ability of the right leg drive circuit will be weakened, and even play a negative role

Images