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This article is about how to realize the normalization of the amplitude display of Matlab fvtool filter frequency response. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

   after designing the filter with matlab, we can use fvtool to see the frequency response of the filter. For example, after we have the coefficient of the filter, we can directly use fvtool.

Fircoe = [0.018641, 0.018275 mai Min 0.020377 Ji 0.071243 MAE 0.049673 Jing.

0.094562, 0.28841, 0.37949, 0.28841, 0.094562 mai Yu 0.049673.

-0.071243memoire 0.020377, 0.018275, 0.018641]

Fvtool (fircoe)

   it is easy to see from the figure that the stopband attenuation is about 40db.

   but there are some filters, the gain after the design is not zero, such as the following cic filter. We first design a CIC filter with dsp.CICDecimator, followed by a CIC compensation filter, which is a FIR filter. Finally, the frequency response of the cascade of the two filters and CIC+FIR is drawn into a picture.

Fs = 100e6

Cic_rate = 4

Cic_flt = dsp.CICDecimator (cic_rate,1,5)

Fpass=fs/cic_rate*0.35/2

Fstop=fs/cic_rate*0.5/2

Cic_comp = design (fdesign.ciccomp (cic_flt.DifferentialDelay,...

Cic_flt.NumSections,fpass,fstop,.3,20,fs/cic_rate))

Comp_fir = dsp.FIRFilter ('Numerator',cmop_coe)

Cascade_flt = cascade (cic_flt,comp_fir)

Fvtool (cic_flt,comp_fir,...

Cascade_flt,'Fs', [fs fs/cic2_rate fs])

Yticks ([- 200VRV 20R0])

   can see from the figure that the compensated FIR filter gain is about 0, while the CIC filter gain is at 60dB. How to normalize the amplitude of the frequency response display of the CIC filter to 0? (because after normalization to 0, the stopband suppression characteristic of the filter can be easily seen in the document.)

   can right-click Analysis Parameters..., in the window of fvtool, as shown below.

Then check Normalize Magnitude to 1 (0dB) and click Save as Default.

In this way, when we draw the filter spectrum with fvtool, it will be displayed in a normalized style.

Thank you for reading! This is the end of the article on "how to normalize the amplitude display of Matlab fvtool filter frequency response". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it out for more people to see!

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