A Channel Simulator to Evaluate Data Transmission Via Satellite under Ionospheric Scintillation – Research Paper Example

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The paper "A Channel Simulator to Evaluate Data Transmission Via Satellite under Ionospheric Scintillation " is a delightful example of a research paper on formal science and physical science. There were several studies conducted by different universities and organizations to determine the effects of Ionospheric scintillation and Total Electron Content. This paper would show the different procedures and calculations that each study created. This paper would also show any advancements or solutions that were developed to address this issue. The University of Nottingham, for example, set up 4 networks of four state-of-the-art GPS Ionospheric Scintillation and TEC Monitor receivers (the NovAtel/AJ Systems GSV4004).

They placed these receivers in strategic locations in Norway and in the UK. Their task was to collect samples or data and compare them with the data that has been collected by other GPS networks collected by the British Isles GPS archive facility. When radio waves are transmitted to/from satellites, they will interact mainly with two parts of the atmosphere: the non-ionized troposphere or the part of earth's atmosphere next to the surface up to 10 km; and the ionosphere or the ionized portion of the atmosphere starting approximately 40 km to 2000 km.

When a signal passes through the ionosphere it will suffer many ionospheric effects due to the electromagnetic radiation from the sun which ionizes the atmospheric particles resulting in a difference in the electron concentration. The main two effects are the Faraday rotation and ionospheric scintillation. Ionospheric scintillation is rapid amplitude and phase, polarization and angle of arrival fluctuation of trans-ionosphere radio waves due to electron density irregularities of the ionosphere. It is found that high ionospheric scintillation occurs frequently during the solar maximum period, an 11-year cycle.

The part of the spectrum from 100 MHz to 7 GHz is affected by the ionospheric scintillation phenomenon mostly at night. A lot of samples have been recorded from different locations and they are available at the Centre. Abstract   To use the available recorded samples to configure channel simulator in software (GISM) based on Nakagami-m distribution’ the bit error rate and the loss of lock condition need to be assessed. By using the results from the software simulator to configure the hardware simulator (satellite modem at Centre) to improve its performance when the satellite link experiences ionospheric scintillation on the path below 6 GHz.

These are considered to be the main motive behind the Ionospheric scintillation conditions. Two areas of the globe are particularly troubled by fading, i.e. , sub- auroral to polar latitudes and a belt surrounding the geomagnetic equator. Amplitude fluctuations of signals above 100 MHz are occasionally noted in middle latitudes but neither their depth of fade nor the frequency of their occurrence is disruptive in proposed or experimental systems.

A map of the night time world viewed from the parochial view of F-layer irregularities might reveal areas of disturbance as seen in Fig. 1; hatch density is roughly proportional to the Occurrence of deep fades. It can be seen that the equatorial zone, during the time depicted (1968, a year of high sunspot number) encompassed plus and minus 10“ to 15” from the geomagnetic equator. The equator forward boundary of the high-latitude region moves to a low of 57” invariant latitude at midnight. The polar cap appears to show diminished.

Scintillation compared to the irregularity region of the auroral zone but the data do not conclusively show this.

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