Decimation filter tutorial

1. How does a decimation filter work?
2. Which filter is used in decimation and interpolation?
3. What is an example of decimation?
4. How do you calculate decimation factor?

How does a decimation filter work?

The decimator passes every M^th sample and discards the other samples. After this operation, the decimation filter changes the sampling frequency f_s of the input signal x(n) to a new sampling frequency f_s/M. The decimation filter then returns an output signal y(n) with the new sampling frequency.

Which filter is used in decimation and interpolation?

11.2 Polyphase Filter Structure and Implementation. Due to the nature of the decimation and interpolation processes, polyphase filter structures can be developed to efficiently implement the decimation and interpolation filters (using fewer number of multiplications and additions).

What is an example of decimation?

The decimation factor is usually an integer or a rational fraction greater than one. This factor multiplies the sampling interval or, equivalently, divides the sampling rate. For example, if compact disc audio at 44,100 samples/second is decimated by a factor of 5/4, the resulting sample rate is 35,280.

How do you calculate decimation factor?

The decimation factor is simply the ratio of the input rate to the output rate. It is usually symbolized by “M”, so input rate / output rate=M.