Power Spectrum Analysis of Solar and Geophysical Parameters

Abstract

Possibility of obtaining power spectra of high resolution by superposition of results of either simple harmonic analysis or Blackman and Tukey spectra of different lags is studied. In the high frequency region (6th and higher harmonics of the fundamental which corresponds to the length of the sample), the superposition methods give results comparable to (and in some aspect better than), those from the Burg method of Maximum Entropy. Results for several artificial samples and a few solar and geophysical parameters obtained by the superposition methods and Burg method are compared. The superposition method is useful only in the high frequency region but does not give spurious peaks and hence seems to be a valuable complement to the Burg method in the high frequency region. For lower frequencies, Burg spectra give better results at larger Lengths of the Prediction Error Filter (LPEF), sometimes far exceeding the usually recommended half data length limit.