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The correlation value can be used alone as a trust factor where low values such as
0.3 mean there a good possibility it's a false reading. A more detailed picture can be
build by combining this information with the energy level as shown in the table:
Low energy levels
High energy levels
Low correlation
Weak signal probably false
reading
High noise level most
likely a false reading
High correlation
Weak signal but likely a good
reading
Ideal conditions very
trust worthy readings
These values can also give some insight for adjusting the transmit power. If the
energy level is low then consider increasing the amplitude and length of the transmit
pulse.
The ISA500 does not average or filter readings in any way. This provides zero lag
making it ideal for control systems.
A simple reliable target tracking algorithm can be created by applying the last known
altitude reading to analyse the multi echo outputs. Using the correlation and energy
values will further improve the reliability.
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