Binary signal modulation ?

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Biro Darius 2018-10-26

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/426263-binary-signal-modulation

Hello guys. I have to modulate a random binary signal such that I obtain the ASK, BFSK and BPSK signals. I should have all the signal representations from the image below.

I have the following code until now, but it doesn't work properly at the ASK step and maybe someone can give me suggestions about BPSK and BFSK steps:

clear all;
Fs = 100000; %Sampling freq
Fc1=5000; % Carrier freq
D=5000; 
data = randint(200,1,2); % Random sequence
t = (0:1/Fs:0.02-1/Fs)';
x=zeros(1,2000);
datai=zeros(200,1);
datap=zeros(100,1);
c1=sin(2*pi*Fc1*t);
c2=sin(2*pi*Fc2*t+pi);
for j=1:100
    if mod(j,2) ~= 0 
       datai(j)=data(j);
    else
       datai(j)=data(j-1);
    end
end
for i=1:2000
    idx=fix((i-1)/20)+1;
    x(i) = data(idx); 
end
ask = c1.*x(i);
figure(1);
subplot(5,1,1); 
plot(t,x); 
axis([0 0.002 0 1.2]);
title('Binary signal');
subplot(5,1,2); 
plot(t,c1);
axis([0 0.002 -1.2 1.2]);
title('Carrier 1');
subplot(5,1,3);
plot(t,ask);
axis([0 0.002 -1.2 1.2]);