物理不可仿製功能(PUF)用於設備的身分驗證及密鑰生成，可在晶片上生成秘密資訊而不需要儲存關鍵資訊。其中環形震盪器(Ring Oscillaor)因其在現場可程式化邏輯閘陣列(FPGA)上易於實現而備受關注。但是基於結構上的不同以及區域性的潛在偏差，不是所有的挑戰與回應對(CRPs)都適合使用，而當我們選擇了高唯一性的回應後，由於操作環境變化又會導致其穩定性不好同時滿足。環震盪器基於鄰近比較且使用配合的架構再利用可編程延遲線(Programmable Delay line)來配置環形震盪器，在不影響比較策略下所獲得的回應的前提下，讓選擇的環形震盪器對兩者的頻率差異更加明顯，以同時滿足獨特性及可靠性，提高FPGA PUF的性能。方法的結果間漢明距離為49.3%，在溫度0℃到70℃間平均內漢明距離為0.4%。

Physical Unclonable Function is used for device authentication and key generation. It can generate secret information on the chip without storing critical information. The ring oscillator has attracted much attention because it is easy to implement on the Field Programmable Gate Array (FPGA). However, due to structural differences and regional potential deviations, not all challenge and response pairs are suitable for use, and when we choose a highly unique response, the change in the operating environment will lead to instability. The ring oscillator is based on the adjacency-comparison which use cooperative architecture and utilize Programmable delay line to configure the ring oscillator, without affecting the response obtained under the comparison strategy. So that the selected ring oscillator pair frequency difference is more significant at the same time for improving the performance of the FPGA PUF. The method can reach 0.4% intra-HD and 49.3% inter-HD.

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