To obtain accuracy up to
1 cm
, we need to measure the time delay between these signals down to
0.00000000003
(1/
30
th
of a nanosecond). The picture below shows a single rise between 0 and 1 (highlighted in the image above).
It is difficult to compare this with the reference to 1/30
th
of a nanosecond, as we do not know at which exact point along
this rise, the change from 0 to 1 happened.
This means that the positional accuracy when using corrected GNSS signals (called code-phase signals) alone is
around 0.5 m.
To obtain a higher level of accuracy, up to 1 cm, another technique needs to be used in conjunction.
https://en.racelogic.support//Product_Info/VBOX_Data_Loggers/VBOX_Sigma/VBOX_Sigma_User_Guide/01_-
_VBOX_Sigma_Introduction
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