本篇論文採用相位累增解調(Phase accumulation demodulation, PAD)技術用以分析5.8 GHz 調變連續波(Frequency modulation continuous wave, FMCW)雷達系統架構所獲取之訊號，使得在複雜環境中依然可以準確量測到生理訊號，並且使用最大似然估計法(Maximum likelihood estimation, MLE)將強環境干擾消除以還原因環境干擾而壓抑之生理訊號變化。除此之外，相位累增解調技術亦對噪聲有較大的容忍度，因此相較傳統使用複數訊號解調，此方法可以不需要以delay-line或是提高頻率調變斜率等方式提高拍頻訊號之頻率，使得系統得以朝可攜式系統進一步發展。實驗設計分為一維金屬板測距、無強環境干擾之生理量測與以金屬板做為干擾訊號之生理訊號量測。最後，在沒有delay-line的情境之下，使用相位累增解調技術之一維測距結果0.5 m至 3.05 m之平均誤差約為4.69 %，其結果與在相同操作頻率下使用delay-line之複數訊號解調結果相近。另外，在無環境干擾之生理訊號量測中，解調出心跳誤差率約為0.24 %；在有環境干擾之情境下，最大心跳誤差亦小於2.25 %。

This paper presents a noise tolerable method for FMCW radar systems to detect vital sign under strong reflected interference signals of stationary clutter. By using phase accumulated demodulation, vital sign detection can be demodulated clearly even under existence of strong clutters influence, and noise can be decreased so that the delay-line can be reduced for the compact system implementation. Moreover, the maximum likelihood estimation used to decrease the influence of the clutter. From the measurement results, the measured absolute range has 4.69% error from 0.5 m to 3.05 m in average. Moreover, the vital sign is 2.25% and 1.49% error with stationary clutter interferer 0.75 m and 1.3 m behind the human target.

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