本論文旨在探討兩種高頻非接觸式硬幣識別的方法，此方法具有簡單的硬體架構以及容易實現等優點。方法一使用高頻正弦波單線圈，以固定的正弦波電壓輸入線圈。當硬幣通過時，藉由線圈阻抗的改變，偵測電流峰值變化及輸入電壓與感應電流之間的相位變化，判斷幣值大小及真偽，實驗結果方法一的辨識率精確度約為85%。方法二為雙線圈繞組。使用固定的方波電壓輸入一次側線圈，當硬幣通過兩組線圈中間時，偵測二次側感應電壓，經由傅立葉進行轉換後，產生基本波及各次諧波，再判斷幣值的大小及其真偽。文中提出標準化的方法，實驗結果可增加辨識率的精確度達到90%。
本文中使用德州儀器公司所生產的TMS320F2808數位信號處理器，作為控制核心，實測結果說明本文所提方法的正確性及可行性。

This thesis proposes two high frequency noncontacting coin identification methods. These two methods use simple hardware circuits and are easy to be implemented. Method 1 uses a one-winding coil, which is excited by sinusoidal voltage. When a coin passes, the impedance of the coil varies. As a result, the peak current and phase difference can be measured to identify the coin value and whether it is a counterfeit coin. The experimental accuracy rate of Method 1 is near 85%. Method 2 uses two-winding coil. A square-wave voltage is inputted into the primary winding. When a coin passes through the two windings, the induced voltage can be measured. After using Fourier series transformation, the fundamental component and harmonic components can be computed to identify the coin value and whether it is a true coin or counterfeit coin. In this paper, a normalization technique is proposed to increase the experimental accuracy rate, which can reach 90%.
A digital signal processor, TMS320F2808, is used as the control center. Experimental results show the correctness and feasibility of the proposed methods.

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