WJMatlab-FSK Coding Scehma

FSK.m

clc;
clear all;
close all;

FigHandle = figure('Menu','none','Position', [350, 200, 700, 500]);

xSignal = [ 1 0 0 1 1 0 1 0 1 1 ];
bitPeriod = 0.1;
Amplitude = 5;
bitRate = 1/bitPeriod;
frequency1 = bitRate*5;
frequency2 = bitRate*2.5;

% Binary Digital Signal Plot
bitArray = []; 
for n = 1 : 1 : length(xSignal)
    if xSignal(n) == 1;
       signalElement = ones(1, 100);
    else xSignal(n) == 0;
        signalElement = zeros(1, 100);
    end
     bitArray = [bitArray signalElement];
end
table1 = bitPeriod/100 : bitPeriod/100 : 100*length(xSignal)*(bitPeriod/100);
subplot(3, 1, 1);
plot(table1, bitArray, 'lineWidth', 2.5); grid on;
axis([ 0 bitPeriod*length(xSignal) -0.5 1.5]);
ylabel('A(volt)');
xlabel('T(sec)');
title('Transmitting Information: Digital Signal');

% Binary FSK Modulation Plot
table2 = bitPeriod/99 : bitPeriod/99 : bitPeriod;                 
ss = length(table2);
waveArray = [];
for i = 1 : 1 : length(xSignal)
    if xSignal(i) == 1
        y = Amplitude * sin(2*pi*frequency1*table2);
    else
        y = Amplitude * sin(2*pi*frequency2*table2);
    end
    waveArray = [waveArray y];
end
table3 = bitPeriod/99 : bitPeriod/99 : bitPeriod*length(xSignal);
subplot(3, 1, 2);
plot(table3, waveArray);
xlabel('T(sec)');
ylabel('A(volt)');
title('Binary FSK Modulation');

% Binary FSK Demodulation Plot
monoArray = [];
for n = ss : ss : length(waveArray)
  table = bitPeriod/99 : bitPeriod/99 : bitPeriod;
  y1 = sin(2*pi*frequency1*table);
  y2 = sin(2*pi*frequency2*table);
  mm = y1.*waveArray((n-(ss-1)):n);
  mmm = y2.*waveArray((n-(ss-1)):n);
  table4 = bitPeriod/99 : bitPeriod/99 : bitPeriod;
  trapezoidal1 = trapz(table4, mm);
  trapezoidal2 = trapz(table4, mmm);
  roundal1 = round(2*trapezoidal1/bitPeriod);
  roundal2 = round(2*trapezoidal2/bitPeriod);
  if roundal1 > Amplitude/2;
    value = 1;
  else roundal2 > Amplitude/2;
    value = 0;
  end
  monoArray = [monoArray value];
end
bitArray = [];
for n = 1 : length(monoArray);
    if monoArray(n) == 1;
       signalElement = ones(1, 100);
    else monoArray(n) == 0;
       signalElement = zeros(1, 100);
    end
     bitArray = [bitArray signalElement];
end
table4 = bitPeriod/100 : bitPeriod/100 : 100*length(monoArray)*(bitPeriod/100);
subplot(3, 1, 3)
plot(table4, bitArray, 'LineWidth', 2.5); grid on;
axis([ 0 bitPeriod*length(monoArray) -0.5 1.5]);
ylabel('A(volt)');
xlabel('T(sec)');
title('Binary FSK Demodulation');