How to design a linear phase low-pass filter by the window function method if the passband cutoff frequency and the stopband cutoff frequency and the minimum attenuation of the stopband are given? Write the design 1. If the passband cutoff frequency and the stopband cutoff frequency as well as the minimum attenuation of the stopband are given, how can a linear phase low-pass filter be designed by the window function method, and write the design steps.

Answer: Convert the analog frequency to digital frequency and determine the characteristics of the ideal filter; Find out by ; choose the appropriate window function and determine the length N of the window function according to the linear phase condition; in MATLAB, it can be obtained by w=boxcar(N) (rectangular window), w=hanning(N) (Hanning window), w=hamming(N) (Hamming window), w = Blackman(N) (Blackman window), w=Kaiser(N,beta) (Kaiser window), and so on to realize the required window functions in the window function design method. The unit impulse response h(n) is derived from h(n)= (n).w(n), 0≤n≤ N-1.

1.If the passband cutoff frequency and the stopband cutoff frequency and the minimum attenuation of the stopband are given, how can a linear phase low-pass filter be designed by the window function method? Write the design steps.

Answer:

① Determine the specifications of the analog bandpass filter first.

② Determine the technical requirements of normalized low pass

③ Design the normalized low pass

④ Convert the low pass to band pass