MLR003R REV2.c Ambient Temperature estimation

When determining the ambient estimate from the ambient raw sensor and the flow raw sensor, the following challenges arise:

Temperatures measured at the Flow Raw sensor arrive at the Ambient Raw sensor with a time delay.

Temperature jumps measured at the Flow Raw sensor arrive at the Ambient Raw sensor in a much smoother form.

In order to eliminate these effects, the following Flow Raw adjustment was made to 1. match the time constants between the flow raw and ambient raw sensors and 2. apply sufficient smoothing.

1. Shifting and smoothing the Flow Raw using a weighted average

Weighted averaging made it possible to shift the curve so that the extreme points coincide in time with those of the ambient raw. The smoothing effect of averaging adjusts the curve to the influence on the ambient raw. The parameters were determined by step-by-step approximation.

2. Smoothing of the Flow Raw using "jump value reduction"

In order to further adjust the curve to the influence on the ambient raw, the temperature jumps in the curve should be weakened. To do this, the last 3 temperature jumps are reduced by a tenth (factor 0.1), and the temperature jump from T-4 to T-3 is reduced by a factor of 0.05. These parameters were also determined by step-by-step approximation.