超導量子干涉元件(Superconducting QUantum Interference Devices；SQUIDs)具有高度的敏感度的磁場感測器，使得我們可以利用它來測量微弱的生物磁場訊號，但是環境的磁場雜訊對於生物磁場的量測影響甚鉅，所以環境雜訊的消除是量測生物磁場必須克服的難題。
文中一開始會介紹幾種現在一般常見的雜訊消除法，包括磁屏蔽屋(Magnetic Shielded Room ; MSR)、梯度計(Gradiometer)、自動補償(Active compensation)、穩定器(Stabilizer)並比較其優劣。
　　最後我們利用商業化的高溫射頻超導量子干涉元件(HTc RF-SQUID)在一個標準型的屏蔽屋中架設一個單通道的心臟磁場量測系統，使用自製的類比放大電路去放大心磁(Magnetocardiography；MCG)訊號以及濾除環境的雜訊，並利用適應性雜訊消除法(Adaptive Noise Cancellation；ANC)去消除雜環境的干擾，實驗結果顯示，適應性雜訊消除法對於60 Hz 以及超低頻的雜訊抑制效果比電子式一階梯度計要來的出色，並在論文的最後規劃一個九通道的心磁量測系統。

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