在高频宽频段内探测脑磁信号功率频谱实验方案的可行性探讨

Feasibility study of the experimental scheme of detecting the magnetic power spectrum in broadband to high frequency

论文提出的检测方案目的是为了验证部分人脑磁功率谱在高频段是否衰减缓慢,很高频段处是否是他人几十倍。方案采用极弱磁传感器DCSQUID作为传感器,直接从SQUID超导环引出电压,并且采取措施控制输入超导环的磁通量小于半个磁通量子,然后接超低噪声的频谱仪或放大器进行宽频段内脑磁信号分析。实验方案中用到了梯度计和磁屏蔽等措施极大幅度的衰减了干扰磁场,并采用磁通聚焦器放大脑磁场,保证探测成功。探测试验获得了很宽频段内可信可验证的脑磁功率谱曲线。探测结果证明了欲探测现象的存在性,有力的支持了方案的可行性。

s Testing purpose is to verify whether part of the brain magnetic power spectrum at high frequencies decay is slow, at high frequency is dozens of times of others.Solutions use DC SQUID that’s very weak magnetic sensor as sensors,directly extraction the voltage from the superconducting ring,and take measures to control the input flux of superconducting ring that is less than half of the flux quantum,then the ultra low noise spectrum analyzer or amplifier is used for signal analysis in wide band.The experimental scheme also uses gradiometer and magnetic shield to attenuate the magnetic field greatly, and uses the magnetic flux concentrator to ensure the detection success.Detection test have garnered brain magnetic power spectrum curve in a broadband segment that’s credible and verifiable.Detection result shows he existence of the phenomenon to detect, and supports the feasibility of the scheme strongly.