Phase shift error of dynamic spectrum

摘要

The phase shift error (PSE) for DS detection is analyzed using frequency domain measure theory of DS. Two factors lead to the difference among different pulse waves, and introduce PSE into DS. Firstly, the period, amplitude and the base line of pulse wave are unstable. Secondly, the phases of pulse waves under different wavelengths are different. The PSE of transmitted and reflected pulse waves are both discussed quantitatively. The results showed that the PSE is correlated with the position of rectangular intercept window that intercepts pulses from the waves. It can be minimized into about 10% by selecting the start points of the windows. Because of the sensor contact pressure, the shapes of transmitted and reflected pulse waves are different. Thus the right intercept locations are at the start of ascending limb and the dicroticpulse respectively according to minimum PSE rule.