PPM Modulator

Hi, Please how can I build a PPM modulator in simulink. The block is not available in my matlab. i am using 2008b

[Fangjun Jiang]

What is PPM?

[Walter Roberson]

Pulse Position Modulation

[ska109]

I've made it working somehow...

Answer 1

[Walter Roberson]

http://www.mathworks.com/help/toolbox/signal/ref/modulate.html

Note that is part of the Signal Processing Toolbox.

The Technical Support note that is relevant, here says that

PPM and PWM are described in “Digital and Analog Communication Systems, 5th Ed.” by Leon Couch. Pages 209-213 describe these modulations, and show circuits that are used for the modulation.

Answer 2

[dave]

Thank you. I will look through it.

Answer 3

[sivasena reddy]

clc;
close all;
clear all;
t=0:0.001:1;
s=sawtooth(2*pi*10*t+pi);
m=0.75*sin(2*pi*1*t);
n=length(s);
for i=1:n
 if (m(i)>=s(i))
 pwm(i)=1;
 elseif (m(i)<=s(i))
 pwm(i)=0;
 end
end
plot(t,pwm,'g',t,m,'r',t,s,'--b');

ylabel('Amplitude');
axis([0  1 -1.5 1.5]);
xlabel('Time index');
title('PWM Wave');
grid on;

[Walter Roberson]

The user had requested Simulink implementation, though.

Also, you appear to be doing PWM (Pulse Width Modification) rather than PPM (Pulse Position Modification)

Answer 4

[Atul Kumar]

clc;
close all;
clear all;
t=0:0.001:1;
s=sawtooth(2*pi*10*t+pi);
m=0.75*sin(2*pi*1*t);
n=length(s);
for i=1:n
 if (m(i)>=s(i))
 pwm(i)=1;
 elseif (m(i)<=s(i))
 pwm(i)=0;
 end
end
plot(t,pwm,'g',t,m,'r',t,s,'--b');
ylabel('Amplitude');
axis([0  1 -1.5 1.5]);
xlabel('Time index');
title('PWM Wave');
grid on;

[Walter Roberson]

How does this differ from https://www.mathworks.com/matlabcentral/answers/24247-ppm-modulator#answer_374142 other than the spacing?