Designing FIR filter

1. What are features of FIR filter and how it is designed?
2. What is the procedure for designing FIR filter using Windows?
3. What is the principle of designing FIR filter using frequency sampling method?

What are features of FIR filter and how it is designed?

An FIR filter is designed by finding the coefficients and filter order that meet certain specifications, which can be in the time domain (e.g. a matched filter) and/or the frequency domain (most common). Matched filters perform a cross-correlation between the input signal and a known pulse shape.

What is the procedure for designing FIR filter using Windows?

To design an FIR filter by windowing, you first decide on an ideal frequency response and calculate the impulse response of the ideal frequency response. You then truncate the impulse response to produce a finite number of coefficients.

What is the principle of designing FIR filter using frequency sampling method?

The main idea of the frequency sampling design method is that a desired frequency response can be approximated by sampling it at N evenly spaced points and then obtaining N-point filter response. A continuous frequency response is then calculated as an interpolation of the sampled frequency response.