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Ionospheric Scintillation : How it disturbs GPS communication

 

How ionospheric scintillation disturbs GPS communication

Tropospheric lightning causes disturbances in the high atmosphere, particularly in the ionosphere. The ionosphere stretches from 60 to 1000 kilometers above the Earth. Lightning, thunderstorms, and other atmospheric phenomena are common in the troposphere layer of our planet. However, similar tropospheric phenomena are increasingly being found to disrupt GPS signals.

    

What is scintillation

When a molecule or ion enters a medium (which may or may not contain ionized particles), it disturbs the entire medium. It causes chemical reactions with the medium's molecules and ions in plain language. As a result, the electrons in outer orbits leave and move to the upper trajectories of molecules or ions. They try to get to stable states / prior states later. The electrons return to their original orbit, emitting light. This is how scintillation happens.


What is ionospheric scintillation

Ionosphere disturbances are sometimes caused by tropospheric (lower atmospheric layer of the Earth where we dwell) events such as lightning. The ionosphere, as we all know, contains ions. As a result, it is frequently referred to as the ionized atmospheric layer. The ionized structures of the layer's ion particles are disrupted by lighting. We know that electrons in the outer orbit absorb radiation, depart, and shift to the higher orbit. Later, it seeks to find stable states, emits energy, and returns to the previous rotation. A similar effect happens when lightning strikes. When the bottom layer of the ionosphere is disrupted, the ionic structure of that area of the ionosphere is also disturbed. It gradually concerns the entire ionospheric layer, changing the particle density of that layer in particular. It eventually releases the energy and becomes lighted.


How ionospheric scintillation disturbs the GPS signal

GPS satellites are known to fly in a medium earth orbit (MEO) at a height of about 20200 kilometers. As a result, they fly above the ionosphere. The ionospheric layer passes the GPS signal that allows us to navigate while on Earth. If the density of particles or ions in the ionosphere abruptly changes, the signal will become more multipath. The GPS signal will become more scattered in plain English than in typical conditions. Then the GPS signal may be less accurate when using GPS navigation to locate a location on Earth.

Satellites communicate with aircraft flying at very high altitudes. The communication between airplanes and satellites can be disrupted if the charged particle density in the ionosphere changes.


 

Q. Why does wireless communication in the troposphere layer?

A. This question is invalid because communicating satellites fly above the ionospheric layer of the atmosphere. Lower orbit satellites fly around 14,000 kilometers above the Earth's surface. Click here to learn more about ionospheric and terrestrial satellite communication.

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