The location of decimated sample in CIC Decimator?

In a CIC Decimator, which sample is chosen among others? For example, here is the original input.

input = [x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 x12]

With the decimation factor of 4, there are four possiblity choosing the samples;

• Possibility 1: output = [x1 x5 x9]
• Possibility 2: output = [x2 x6 x10]
• Possibility 3: output = [x3 x7 x11]
• Possibility 4: output = [x4 x8 x12]

In CIC Decimator, which possiblity is used and is there any parameter to choose other possibility?

Answer 1

[Vinay]

Hi @Jay,

The 'CIC decimator' downsample the input based on the decimation factor(R) after passing through the cascaded integrators.

Given a decimation factor of 4 the output is given as

I hope this helps!