Interpolation filter design

1. What is an interpolation filter?
2. Is interpolation a low pass filter?
3. What are the methods of filter design?
4. What is interpolation in sampling?

What is an interpolation filter?

The interpolation filter contains an L-fold expander followed by a lowpass FIR filter H(z). The L-fold expander inserts L−1 zeroes between consecutive samples to the original signal x(n) and changes the sampling frequency f_s of the original signal x(n) to a new sampling frequency Lf_s.

Is interpolation a low pass filter?

Interpolation is a two step process: upsampling followed by low pass filtering.

What are the methods of filter design?

The filter design methods provided in the DFD toolkits include Kaiser window, Dolph-Chebyshev window, and equi-ripple for FIR filters; and Butterworth, Chebyshev, Inverse Chebyshev, and Elliptic for IIR filters. In addition, the DFD toolkit has some Special Filter Design VIs.

What is interpolation in sampling?

In the domain of digital signal processing, the term interpolation refers to the process of converting a sampled digital signal (such as a sampled audio signal) to that of a higher sampling rate (Upsampling) using various digital filtering techniques (for example, convolution with a frequency-limited impulse signal).