Plotting IIR filter error

I have an IIR filter I am trying to plot, but I am not sure what I am doing wrong here. Can someone please help?
My code:
%% This is a first part of an exercise.
% Here you are implementing the transfer function H(z).
% Pass different values of theta and r to have differnt outcome.
clc; clear all;
%% Part -1 simulation
% initialize r
r = 0.99 ;
%initialize theta
theta = pi/3 ;
% initialize omega vector. Let, ω to start from 0 to pi with % 200 intermediate values.
w = 200 ;
% Now, define z = e^(j*w).
z = exp(1i*w);
% implement H
H = 1./(1 - (2*r*cos(theta)*(z.^-1))+((r^2)*(z.^-2)));
% Now, plot the filter magnitude response in dB scale w.r.t w.
figure;plot(w, );grid on;
xlabel('normalized frequency'); ylabel('amplitude in dB')
title('Frequency and phase response at r = and theta = ');

2 个评论

What result are you supposed to get, and what result are you getting?
I have not even been able to get anything to show up in the plot. I need it to plot properly.

请先登录,再进行评论。

 采纳的回答

You are plotting one point, so you need to plot a marker instead of a line.
I am not certain what you are doing, so consider this example:
% Now, define z = e^(j*w).
z = @(w) exp(1i*w);
% implement H
H = @(w) 1./(1 - (2*r*cos(theta)*(z(w).^-1))+((r^2)*(z(w).^-2)));
% Now, plot the filter magnitude response in dB scale w.r.t w.
w = linspace(-100*pi, 100*pi, 250);
figure;plot(w, abs(H(w)));grid on;
xlabel('normalized frequency'); ylabel('amplitude in dB')
title('Frequency and phase response at r = and theta = ');
Experiment to get the result you want.

更多回答(0 个)

类别

帮助中心File Exchange 中查找有关 Digital and Analog Filters 的更多信息

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by