The invention relates to a signal detection method suitable for processing a photoplethysmography signal generated from photoplethysmogram (PPG) sensor, which comprises the following steps: (a) using a wave filter to perform baseline filtering and band-pass filtering to the photoplethysmography signal (b) using a processor to calculate a regional slope value corresponding to each sampling point included in the photoplethysmography signal (c) based on a threshold value, using the processor to determine whether the regional slope value corresponding to the i-th sampling point is the regional maximum slope value corresponding to the i-th sampling point and (d) using the processor to search the sampling point corresponding to the regional slope value which turns into negative from positive, and determine the same as a peak position among those sampling points subsequent to the regional maximum slope value, so as to accurately detect the peak-to-peak interval of the photoplethysmography signal.一種訊號偵測方法適用於處理來自PPG感測器的一光體積變化訊號,並包含以下步驟:(a)藉由一濾波器對該光體積變化訊號作基線濾波及帶通濾波;(b)藉由一處理器對該光體積變化訊號所包含的每一取樣點,計算一對應的區域斜率值;(c)藉由該處理器根據一門檻值,判斷對應第i個取樣點的該區域斜率值是否為對應第i個取樣點的一區域最大斜率值;(d)藉由該處理器在每一區域最大斜率值之後的該等取樣點中,搜尋並決定對應該區域斜率值由正轉負的該取樣點為一波峰位置;進而能正確地偵測該光體積變化訊號的峰峰值間隔。(a)~(d)‧‧‧步驟
