### Now that we have the overall operation of the localization process, let's look at how the signal is received and how the signal is processed:
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@@ -133,20 +133,36 @@ The satellites of the GNSS system are equipped with **several atomic clocks**; h
# PART 6 : TO GO FURTHER...
The **Allan variance** is a statistical method used to measure the stability of a frequency or time standard over time. It is a measure of the frequency stability of a clock or oscillator, and is commonly used in the field of time and frequency metrology.
[Allan's variance](Allan's%20variance)
A coordinate system for GNSS is a reference framework used to define the position and orientation of objects in space.
[Coordonate system](Coordonate%20system)
A decoy is a false signal that is designed to mimic the signals emitted by real GNSS satellites. It is used as a countermeasure against GNSS **jamming** and spoofing attacks, where an attacker transmits false signals to disrupt or manipulate the receiver's navigation solutions.
[Decoy](Decoy)
Dilution of Precision (DOP) is a measure of the geometric quality of the satellite configuration in the sky, as seen from a receiver. It is used to determine how well a set of satellites are positioned to provide an accurate navigation solution.
[DOP](DOP)
an ephemeris is a set of data that provides information on the precise location and velocity of a satellite at a specific point in time. It is used by a GNSS receiver to calculate the position and velocity of the receiver by determining the distance between the receiver and the satellites
[Ephemeris](Ephemeris)
Inertial Navigation is a method of navigation that uses accelerometers and gyroscopes to track the motion of an object and determine its position and velocity. It is commonly used in applications where GNQSS signals are not available or unreliable, such as in deep space or underwater navigation.
[Inertial navigation](Inertial%20navigation)
**Jamming** refers to the deliberate transmission of radio frequency signals in the same frequency band as the GNSS signals, with the intent of disrupting or overpowering the legitimate GNSS signals.
