www.gusucode.com > dsp 案例源码程序 matlab代码 > dsp/FilterDesignUsingFirceqripExample.m
%% Filter design using |firceqrip| % Design a 30th order FIR filter using |firceqrip|. b = firceqrip(30,0.4,[0.05 0.03]); fvtool(b) %% % Design a 30th order FIR filter with the |stopedge| keyword to define the % response at the edge of the filter stopband. b = firceqrip(30,0.4,[0.05 0.03],'stopedge'); fvtool(b) %% % Design a 30th order FIR filter with the |slope| keyword and r = 20. b = firceqrip(30,0.4,[0.05 0.03],'slope',20,'stopedge'); fvtool(b) %% % Design a 30th order FIR filter defining the stopband and specifying that % the resulting filter is minimum phase with the |min| keyword. b = firceqrip(30,0.4,[0.05 0.03],'stopedge','min'); fvtool(b) %% % Comparing this filter to the filter in Figure 1. The cutoff frequency % |wo = 0.4| now applies to the edge of the stopband rather than the point % at which the frequency response magnitude is 0.5. %% % Viewing the zero-pole plot shown here reveals this is a minimum phase % FIR filter - the zeros lie on or inside the unit circle, z = 1 % % fvtool(b,'polezero') %% % Design a 30th order FIR filter with the |invsinc| keyword to shape the % filter passband with an inverse sinc function. b = firceqrip(30,0.4,[0.05 0.03],'invsinc',[2 1.5]); fvtool(b) %% % The inverse sinc function being applied is defined as % 1/sinc(2*w)^1.5.