本研究以異相性磁敏電阻感測器為基礎，設計一個雙頻磁力感測平台，可量測低頻的直流磁場與60Hz交流磁場。本平台具有16位元的基本資料解析度以及5kHz 的取樣頻率，最高解析度可達2 nT ，足以研究直流環境磁場與交流環境磁場在被周邊環境物品殘磁與市電交流磁場影響。 透過實驗探討磁力計之背景雜訊，以設計FIR低通濾波器及關連函數演算法直流磁場與交流磁場，並以Helmholtz提供可控磁場用遞迴最小平方法，實現自動校正訊號放大倍率及訊號偏差。最後經實測經過校正後，本磁力計與實際磁場的標準差可達40 nTesla 以下。 ;This study is based on the anisotropic magnetic resistance sensors. We have designed a sensor platform, which can measure DC magnetic and 60Hz AC magnetic. This platform has 16bit ADC with redefine resolution down to 2 nTesla and sampling rate up to 5kHz, which is enough to measure the DC magnetic effect by Residual magnetism and AC magnetic effect by electricity for life. By experiment of measure background noise, we designed FIR filter to measure DC magnetic and using convolution to measure AC magnetic. Using Helmholtz Coil and recursive least square to correction gain and offset. Prove that the standard deviation from real magnetic is under 40 nTesla
