Automatic Data Downloading Program (DDP) in Determining Regional Ionosphere Model

Yıl 2018, Cilt: 7 Sayı: 1, 17 - 28, 20.04.2018

Fuat Başçiftçi , Cevat İnal , Ömer Yıldırım Sercan Bülbül

Öz

GNSS (Global Navigation Satellite System) signals pass
through various layers of the atmosphere until they reach the receiver on the
Earth. One of these layers is the Ionosphere. Ionosphere may be defined as the
atmospheric layer that consists of the gasses that are ionized with sunrays
located 60 and 1100 km above the ground level with important effects on the
signals used by satellite-based positioning, short-wave communication, and
other communication systems. One of the important parameters that express the
characteristics of the Ionosphere is the Total Electron Content (TEC), which is
a function of the electron density that shows variations with the radiation of
the Sun. The TEC value cannot be obtained directly from GNSS
measurements; however, it may be predicted with the combinations produced.
In the scope of the present study, the Bernese v5.2 GNSS scientific Software
that was developed by the Swiss Bern University Astronomy Institute (AIUB) was
used in the determination of the TEC values for the Regional Ionosphere model.
Before the stage in which the TEC values are determined with the Bernese v5.2
GNSS Software, some files must be downloaded from the Internet in the Bernese
format according to GPS day/week and year/the day of year values and copies to
the DATAPOOL folder, which is created with the use of the software. For this
purpose, it has been ensured that the files in the Bernese format are obtained
from the relevant Internet addresses in an automatic manner by using a series
of commands with the name Data Downloading Program (DDP) in the MATLAB for the
purpose of facilitating the manual data collection process and eliminating
other possible difficulties that might appear. The Regional TEC values are
computed with the Bernese v5.2 GNSS Software by using the downloaded files.

Anahtar Kelimeler

GNSS, Bernese, MATLAB, Total Electron Content (TEC), Ionosphere

Kaynakça

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