5. Efficiency of SPLA: Theoretical validation
Efficiency of SPLA in detecting ionospheric disturbances without
amplitude aliasing during a geomagnetic storm was theoretically
validated by Shimna and Vijayan (2020). In this study, we first
theoretically test the efficiency of SPLA in detecting aliasing and
artifact free TIPs and CIPs over the conventional methods under two
simulated scenarios and then using observational data sets. In the first
scenario, the ability to detect sharp static variations was tested on a
synthetic TEC time series added with step functions. In the second
scenario, power of resolving the sharp static variations from the
perturbations of comparable amplitude were tested using a synthetic TEC
time series superimposed with both sharp static variations and a
simulated perturbation.
The synthetic TEC was obtained by modeling the TEC using International
Reference Ionosphere model IRI-2012 (Bilitza et al., 2014) at every IPP
(IRI-TEC) along the satellite track traced by GPS satellite PRN04
observed at a uniform interval of 30 seconds from Hyderabad GPS station
(HYDE) on 1st December 2004 from 06:52UT to 13:22UT
(Fig. 2. Top-left). The satellite track will be represented throughout
this paper by PRN (Psuedo Random Noise) number of the GPS satellite
prefixed with four letter GPS station code from where the GPS satellite
was observed, for example, HYDE04.