The method makes it possible in particular to determine the heartbeat of a person by means of a pulse measuring device (1). Light waves are generated by two light sources (5, 6) with a first wavelength (λ1) which is sensitive to the pulse beat and the movement of the person, and with a second wavelength (λ2) which is different from the first wavelength and is sensitive to the movement of the person. The light waves are transmitted in the direction of the skin of the person. The photodetector (7) detects the reflected light waves in order to provide electrical measurement signals. Thereafter, a calculation is made of at least one non-coherent power spectrum on the basis of a spectral coherence function γ which takes into account the dependence between the measurement signals relating to the first wavelength and to the second wavelength by the formula SNC=(1-γ2)‧, where is the average Fourier power spectrum of the measurement signals relating to the first wavelength of the sensed light waves, and where γ2 is between 0 and 1. Finally, the heartbeat is determined on the basis of the non-coherent power spectrum.該方法使藉由脈搏測量裝置(1)來判斷人的心跳變得可行。由兩個光源(5及6)產生光波,其具有對人的脈搏跳動及移動敏感之第一波長(λ1)及與第一波長不同且對人的移動敏感之第二波長(λ2)。在人的皮膚方向中傳送光波。光偵測器(7)偵測反射的光波以提供電性測量信號。之後,根據頻譜相干函數γ來進行至少一不相干功率譜之計算,該頻譜相干函數γ藉由公式將關於第一波長與關於第二波長之測量信號間的相依性納入考量,其中為關於經感測光波的第一波長之測量信號的平均傅立葉(Fourier)功率譜,且其中γ2在0與1之間。最後,根據不相干功率譜來判斷心跳。1...脈搏測量裝置2...光學偵測單元3...微控制器單元34...顯示單元5、6...LED二極體7...光偵測器8...類比-數位轉換器9...處理單元10...數位-類比轉換器11...RAM型記憶體12...ROM型記憶體13...電池30...資料及控制匯流排
