室內定位技術目前仍難以廣泛被導入使用，主要原因在於定位精度的需求、佈署困難度及感測器成本。基於地球磁場感測是新興的室內定位技術，具備無需事先進行環境佈建及感測器成本較低的優勢，但卻存在精度不足的問題。本研究提出一個基於地磁感測器陣列的室內定位方法，我們使用三個磁場感測器構成感測器陣列，以量測室內空間的磁場分布。感測器擷取的原始磁場感測訊號X / Y / Z 被轉換成磁場強度、磁傾角、和磁偏角，我們使用這些感測資料和感測器之間空間差分作為室內空間位置辨識的特徵向量。並透過機率神經網路的辨識模型來推估座標位置。最後我們在11.4m x 6.6m 的實驗場域中驗證本方法定位的準確性，實驗結果顯示使用本研究所提出之作法，其誤差量90%皆能維持在1m 以內，相較於傳統方法，可大幅降低定位座標的誤差。

An indoor position system has not been widely applied in life, the main reason are the demand of accuracy, the difficulties of disposal and the cost of sensor. It is a new technology about an indoor positioning system based on geomagnetic sensor array, it is an advantage that we don’t need to dispose the environment and we have the lower sensor cost, but it has a problem about the insufficient accuracy. The research provide an indoor positioning method
based on geomagnetic sensor array, we use three geomagnetic sensor to compose the geomagnetic sensor array, therefore we can measure the geomagnetic disposal indoors. The original geomagnetic sensor signal X / Y / Z from sensor are transferred to magnetic field,magnetic dip and magnetic declination, we use the data and the disparity between the space of sensor as vector of position determination, and we estimate the coordinate by the recognition of probabilistic neural network. Finally, we verify the accuracy at 11.4m x 6.6m platform, the experimental results indicated that we can maintain the 90% error within 1m by this method,it can reduce the coordinate error compare to the traditional method.

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