![]() abs(h) is the magnitude responseĮdit : Does wn=0.34 corresponds to 42. Plot(f,20*log10(abs(h))) % we will use 20log10() for ploting the mag. X=fir1(N,wn,ftype,kaiser(N+1,beta)) % designing the corresponding fir filter ( note that fir1 takes an even filter order so we wrote N+1) , order of the filter, filter type and betta according to the design specs. 2 for Octave and Matlab version listings), and saveplot is a trivial compatibility wrapper for the print function, which saves the current plot to a disk file (. This function will return the cuttoff freq. =kaiserord(fcuts,mags,devs,fs) % using kaiser window for designing the fir filter. matlab freqs freqz 1.freqs h freqs (b,a,w) h,w freqs (b,a) h,w freqs (b,a,f) freqs (b,a) 1. Mags= % The required filter amplitude in these bands (Absolute value not in dB)ĭevs= % Passband and stopband ripples (Absolute value not in dB) Plot the magnitude frequency response of the filter bank. So what is wrong with my code? Here is the code (with the required filter specifications): fs=250 įcuts= % passband and stopband frequencies Call freqz to get the complex frequency response, H, of the filter bank and a vector of frequencies, f, at which the response is calculated. My question is that when I plot the amplitude response, the -3dB point occurs at frequency above 100 Hz, which means that the cutoff frequency is not equal to 42.5 Hz. Doing this, the returned wn is equal to 0.34 (returned by kaiserord()), which when I convert it to Hertz it gives me 42.5 Hz as required. I need to plot the filter's magnitude and phase responses with the x-axis as frequency in Hertz instead of plotting them with the normalized angular frequency. example b,a butter (n,Wn,ftype) designs a lowpass, highpass, bandpass, or bandstop Butterworth filter, depending on the value of ftype and the number of elements of Wn. With no output arguments plots the magnitude and phase response versus frequency in the current figure window.įreqs works only for real input systems and positive frequencies.I am designing an FIR filter in Matlab using a Kaiser window. Description example b,a butter (n,Wn) returns the transfer function coefficients of an n th-order lowpass digital Butterworth filter with normalized cutoff frequency Wn. freqz determines the transfer function from the (real or complex) numerator and denominator polynomials you specify and returns the complex frequency response. Picks f number of frequencies on which to compute the frequency response h. ![]() freqs evaluates the frequency response along the imaginary axis in the complex plane at the angular frequencies in rad/sec specified in real vector w, which must contain more than one frequency.Īutomatically picks a set of 200 frequency points w on which to compute the frequency response h. Returns the complex frequency response of the analog filter specified by coefficient vectors b and a. luego en matlab tienes el vector h de datos de frecuencia (eje horizontal) ( h,w freqz (ha,n) )generas un nuevo vector para el eje vertical con el factor de convesrion al que lo puedes U finalmente ploteas (h,U). Given the numerator and denominator coefficients in vectors b and a. Freqs (Signal Processing Toolbox) Signal Processing Toolboxįreqs returns the complex frequency response H( j ) (Laplace transform) of an analog filter
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |