# Matlab hw

% ExDM.m % Example of sampling, quantization, and zero order hold clear; clf; td=0.002; % original sampling rate 500 Hz t=[0:td:1.]; % time interval of 1 second xsig=sin(2*pi*t)-sin(6*pi*t); % 1Hz+3Hz sinusoids Lsig=length(xsig); ts=0.02; % new sampling rate=50Hz Nfact=ts/td; % send the signal through a 16-Level uniform quantizer Delta1=0.2; % First select a small Delta=0.2 in DM1 s_DMout1=deltamod(xsig,Delta1,td,ts); % obtained the DM signal % plot the original signal and the DM signal in time domain figure(1); subplot(311); sfig1=plot(t,xsig,'k',t,s_DMout1(1:Lsig),'b'); set(sfig1,'Linewidth',2); title('Signal g(t) and DM signal'); xlabel('time (sec)'); axis([0 1 -2.2 2.2]); % % apply DM again by doubling the Delta Delta2=2*Delta1; s_DMout2=deltamod(xsig,Delta2,td,ts); % obtained the DM signal % plot the original signal and the DM signal in time domain subplot(312); sfig2=plot(t,xsig,'k',t,s_DMout2(1:Lsig),'b'); set(sfig2,'Linewidth',2); title('Signal g(t) and DM signal with doubled stepsize'); xlabel('time (sec)'); axis([0 1 -2.2 2.2]); % Delta3=2*Delta2; % Double the DM delta again s_DMout3=deltamod(xsig,Delta3,td,ts); % plot the original signal and the DM signal in time domain subplot(313); sfig3=plot(t,xsig,'k',t,s_DMout3(1:Lsig),'b'); set(sfig3,'Linewidth',2); title('Signal g(t) and DM signal with quadrupled stepsize'); xlabel('time (sec)'); axis([0 1 -2.2 2.2]);