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a) LPF is a rect function in the frequency domain and sinc function in the time domain. b) Here is the code I used %E416_p223 %rjb %8/20/2014 %HW problem 2.235 CS Haykin clear BT =100; % 5, T=1; B=BT/T; delta_t = T/200 %T/100, T/150,T/200, T/1000 t = [-6*T:delta_t:6*T]; %pulse of unit amplitude x = zeros(size(t)); index = find(abs(t)<T/2); x(index)=1; % truncated impulse response t1 = [-3*T:delta_t:3*T]; h=2*B*sinc(2*B*t1); %filter response y = filter(h,1,x)*delta_t; subplot(311), stem(t,x), axis([-1,1,-0.25,1.25]),grid subplot(312), stem(t1,h), axis([-1,1,1.1*min(h),1.1*max(h)]),grid subplot(313), stem(t-3*T,y),%axis([-T,T,-0.25,1.25]),grid c) BT Overshoot (%) Ripple Period 5 9,98 1/5 10 9.13 1/10 20 9.71 1/20 100 100 No visible ripple d) t Overshoot (%) Ripple Period T/100 100 No visible ripple. T/150 16.54 1/100 T/200 ~0 No visible ripple. a) LPF is a rect function
