Re: min/max delay filters

Hello,

This is help for a homework question, and I would not like someone to do
it for me, just help point me in the right direction.

The question is:
Consider the two-element filter [1.0 0.6]. Construct a finely spaced
dimensionless
frequency vector that extends from -1 to 1. Calculate and plot the
amplitude and phase lag
spectra for the filter. Identify the Nyquist frequency on the plots.

My thoughts are to use the freqz function, and set

A = 1
B = [1.0 0.6]
f = [-1:1/500:1]
fs = 500

And then run freqz(B,A,f,fs)

the plots just dont look right to me though.

does anyone see where I am going wrong? I know with filters there are
other things I could run (filter, fir, iir) but I am having trouble
knowing
when one is appropriate.

thanks!

erin




Hi Erin,

the amplitude response of the filter, is the absolute of the fourier
transform of it's impulse response (B). The phase response of the filter is
the angle of the fourier transform of the impulse response. So use the fft
command on B and then plot the absolute and angle of the result.

Manolis
.

Relevant Pages

  • FIR Hilber Transformer
    ... how can it be found that the filter is a Hilbert transformer or not? ... How can I plot a phase response of a HT in Matlab similar to one shown on the website? ... This is not a homework question, ...
    (comp.dsp)
  • Re: Upsampling real-time data using DFT
    ... convolution combined with interpolation, ... It is a brick wall filter so ... the impulse response of your ad-hoc rectangular ...
    (comp.dsp)
  • Re: why we want to do folding while performing convolution
    ... Below, I have drawn an example of a five-tap FIR filter, being of course ... We have signal samples coming in from the left into a RAM 'delay-line.' ... This is intended to be the impulse response of an example single-pole ... be a replica of the stored impulse response of the example low-pass ...
    (comp.dsp)
  • Re: design an iir by time-domain impulse response
    ... of a recursive iir filter, for a given time-domain impulse response. ...
    (comp.dsp)
  • Re: why we want to do folding while performing convolution
    ... Below, I have drawn an example of a five-tap FIR filter, being of course an example of convolution. ... The output of successive convolutions will then be a replica of the stored impulse response of the example low-pass filter. ... In other words, if the impulse response of the FIR filter is to be the same as the example filter, the time relationships between the stored signal samples and the stored impulse-response samples must be reversed or 'flipped' ...
    (comp.dsp)