FUTEK IHH500 Series User Manual

Page 70

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EM1001-B

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This is known as a moving average because the average at each k

th

instant is based on the most recent set

of n values. In other words, it is a moving window of n values that are used to calculate the average of the
data sequence (see Figure 1).

Figure 1: Moving Average of n Data Points


The averaging process can be improved if the calculations can be performed in a recursive fashion.
Equation 1 can also be represented as the previous total of n – 1 samples plus the new sample, and then
divided by n.

(3)

Using Equation 1, we can derive the equation for

(4)

This can be rearranged as shown in Equation 5:

(5)

Using Equation 5, we can replace the value of

in equation 3 with

This yields Equation 6:

(6)

Equation 6 can be simplified to equation 7:

(7)

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