Improve template parameter estimation for pseudo-periodic signal processing and application

In order to process and analyze pseudo-periodic signals online in time-domain for the system with limited hardware resource, this paper presents a simplified method of template function parameters estimation. Treating the pseudo-periodic signals in short time as periodic, the method selects Fourier series as template and the initial parameters are estimated by fitting off-line. The base frequency of the template is determined from the periods of signal measured and the multiples of the base frequency are treated as the estimations of high-order frequency. Adopting square sum of the matching error between measurement and template as cost function, the method estimates or calculates the characteristic parameters of the pseudo-periodic signal by adjusting online amplitude and order of the template series. The experiment on processing radial artery pulse pressure measured by PVDF sensor online shows that the improved method is effective and helpful to simplify pulse wave detecting system.