Scaling and stationarity analysis of discrete time signal of Solar Radio flux

In the present work, we have considered the daily signal of Solar Radio flux of 2800 Hz recorded daily by radio telescopes near Ottawa (operated during 14
^th
February, 1947-31
^st
May, 1991) and Penticton, British Columbia, Dominion Radio Astrophysical Observatory (operating since 1
^st
June, 1991) during the period from 29
^th
October, 1972 to 28
^th
February, 2013. We have applied FIR nonlinear phase filter on the present discrete signal to denoise it. The memory of this denoising signal has been analyzed and it indicates short memory trend (anti-persistent) hidden in this spectrum. Then we have examined whether the signal possesses stationary properties. On the basis of autocorrelation analysis, quasi or partly stationary nature of the spectrum has been revealed.