On the Best Settings to Calculate Ionospheric Irregularity Indices From the In Situ Plasma Parameters of CSES-01

Electron density (Ne) and temperature (Te) values
recorded by the Langmuir probe onboard the first satellite of the
China Seismo-Electromagnetic Satellite (CSES-01) mission allow
calculating quantities such as the rate of change of electron density
index (RODI) and the rate of change of electron temperature index
(ROTEI), which are essential to describe the ionospheric irregularities
and their dynamics. These two indices depend significantly
on two parameters, i.e., the measurement sampling time and the
width of the sliding windows used for their computation. Ne and Te
measurements fromCSES-01 present two different sampling times,
i.e., 3 s in the survey mode and 1.5 s in the burstmode. The purpose
of this article is to understand what are the best values of these two
parameters to be used when computingRODI andROTEI based on
CSES-01 data. The main results of the study show the following:
The shorter the data sampling time, the higher the values of the
calculated ionospheric indices,which means that it is not possible to
merge values of either RODI or ROTEI calculated with a different
sampling time; the wider the sliding window used to calculate the
indices, the higher the indices. A reasonable compromise between
the data sampling time and the satellite orbital velocity suggests
that the optimal way to calculate RODI and ROTEI from CSES-01
should be done by considering data with a 3-s sampling time (i.e.,
in the survey mode or in the downsampled burst mode), and a 24-s
wide sliding window.