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(Solved) : Pcm Encoding Https Wwwmathworkscom Matlabcentral Fileexchange 34610 Pcm Matlab Code Conten Q29685978 . . .

% ============
% PCM ENCODING
% ============
% fromhttps://www.mathworks.com/matlabcentral/fileexchange/34610-pcm-matlab-code/content/Untitled.m
% modified by JEC for CSE408 HW3

clc;
clear all;

f = 2; % input frequency 2Hz

fs = 20; % sampling at 20Hz
Ts = 1/fs;

fss = 1.e4; % fine sampling for the time axis 10ksampls/sec
Tss = 1/fss;

t = 0:Tss:2-Tss; % continuous time axis, 2 seconds, 20ksamples
d = Ts/40:Ts:2+Ts/40; % discrete time axis 41 samples startingat…
% a very small value, 1/40 of the Sampling Period
  
% rectangular pulses 1/Ts wide are 20 samples (1/fs*25)/(1/Tss))wide in the t scale (which
% is 10000Hz, while fs is 20Hz
p = pulstran(t,d,’rectpuls’,1/(fs*25));

% =================
% Analog MSG Signal
% =================
% simple sinusoid at f (2fps) with a +shift of 1.1 to keep allvalues above
% zero
m = sin(2*pi*f*t)+1.1; % constant 1.1 is added so all values arepositive
% HW part 3 — AM Input
% comment the line above (and assign a new value to it)
% add 1Hz 25% amplitude modulation to the input m, i.e.positive
% amplitude variation between 0.75 and 1.25
% Hint: the modulating sin or cos amplitude is 0.25, so you need toadd 1.0
% observe the reconstructed signal, why is it not correct?
% what adjustment do you need to do to the signal so the dynamicrange
% remains as before?
% insert your code here..

% =================
% Sampled signal
% =================
ms = m.*p;

% =================
% Quantized Msg
% =================
qm = quant(ms,2/16);
em = 8*(qm);

% =================
% ENCODING MSG
% =================

% get the sampled signal
j = 1;
for i=1:length(em)
if (em(i)~=0 && em(i-1)==0) ||((i==1)&&(em(i)~=0))
x(j) = em(i)-1;
j=j+1;
end
end

% convert to binary representation
z = dec2bin(x,5);
z = z’;
z = z(:);
z = str2num(z);

% z is the binary string sent through the channel, using 5-bitsymbols

% =============
% PCM DE-CODING
% =============
% the input is z
% we know in advance that the stream is made of 5-bit symbols
rb = z;
l = length(rb);

for i = 1:l/5
q = rb((5*i)-4:5*i);
q = num2str(q’);
x1(i) = bin2dec(q);
e(i) = x1(i)+1;
end

e = e/8;
ms1 = e; % recovered sampled signal

% Now recover the original signal by interpolating e using
% fs*upSamplingFactor samples
upSamplingFactor = 5;

rm = interpft(e,fs*upSamplingFactor); % This is the receivedsignal

% define discrete time axis for recovered signal
Tsr = 2*Ts/upSamplingFactor;
dr = 0:Tsr:2-Tsr;

% HW 2 Part 1: insert your PSNR code here

MSE = mean((m-rm).^2)

% ==================
% Plotting Signals
% ==================

% uncomment to look at intermediate signals and fordebugging
%start of comment
%
% figure(1);
% subplot(2,1,1)
% plot(t,m,’b’,t,ms,’r’);
% legend(‘Analog Msg’,’Sampled Msg’)
% grid;
% xlabel(‘t –>’);
% ylabel(‘Amplitude’);
% axis([0 2 0 2.25]);
%
% subplot(2,1,2)
% plot(t,ms,’k’,t,qm,’r’);
% legend(‘Sampled Msg’,’Quantized Msg’)
% grid;
% xlabel(‘t –>’);
% ylabel(‘Amplitude’);
% axis([0 2 0 2.25]);
%
% figure(2);
% subplot(2,1,1)
% plot(t,em,’b’)
% xlabel(‘t –>’);
% ylabel(‘Amplitude’);
% title(‘Binary Encoded Msg sent’);
% grid;
% axis([0 2 -0.5 16.5]);
%
% figure(3);
% stem(ms1,’Marker’,’.’);
% title(‘Recovered Sampled Msg’)
% grid;
% xlabel(‘t –>’);
% ylabel(‘Amplitude’);

%end of comment

figure;
plot(t,m,’b’);
title(‘Original Signal’)
grid;
xlabel(‘t –>’);
ylabel(‘Amplitude’);
axis([0 2 0 2.25]);

figure;
plot(dr,rm,’b’);
title(‘Recovered Analog Msg’)
grid;
xlabel(‘t –>’);
ylabel(‘Amplitude’);
axis([0 2 0 2.25]);

1. Compute PSNFR MAXY MSE PSNR 20 logio Using the max of the reconstructed signal rm and the squared differences between original signal m and the reconstructed signal rm NOTE: keep in mind that in order to compute MSE, the arrays m and rm must be of the same size. You need to add code after line or modify it rm – interpft e,fs upSamplingFactor); You must insure that the recovered message, rm is the same size as m You can either modify upSamplingFactor in the line above or make a new call to interpft to make sure the new rm is the correct size. See Matlab help for interpft Show transcribed image text

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Answer to Pcm Encoding Https Wwwmathworkscom Matlabcentral Fileexchange 34610 Pcm Matlab Code Conten Q29685978 . . .