clear;
%Ëæ»ú²úÉú³¤¶È´óÓÚ1000µÄ¡®0¡¯¡¢¡®1¡¯ÐźÅÐòÁУ¬¶ÔÆä½øÐÐQPSKµ÷ÖÆ
%¶¨Òå´ý·ÂÕæÐòÁеÄάÊý N
global N
N=2000;
%¶¨Òå²úÉú¡®1¡¯µÄ¸ÅÂÊΪ p
global p
p=0.5;
%²úÉúËæ»ú¶þ½øÖÆÐòÁÐ
s_qpsk=randsrc(1,N,[1,0;p,1-p]);
%»­³öÉú³ÉµÄËæ»úÐòÁÐͼ
figure(1);
stem(s_qpsk);
axis([0 50 -0.5 1.5]);
xlabel('άÊýN')
ylabel('ÐźÅÇ¿¶È')
title('0/1µÈ¸Å·Ö²¼µÄÐźÅ')

%********QPSKÐźŵÄÊý×Öµ÷ÖÆ********
[m_qpsk1,m_qpsk2]=qpsk_modulation(s_qpsk);
figure(2);
plot(m_qpsk1,m_qpsk2,'r*');
axis([-2 2 -2 2]);
title('QPSKµÄÐźſռäͼ');

%********²åÖµ£¬ÏàÁÚÐźżä²åÈë7¸öÁãµã********
insert_qpsk1=upsample(m_qpsk1,8);
insert_qpsk2=upsample(m_qpsk2,8);
%»­³ö²åÖµºóµÄÐòÁÐ
figure(3);
subplot(2,1,1);
plot(insert_qpsk1(1:90),'ro');
axis([0 100 -1.5 1.5]);
hold on;
plot(insert_qpsk1(1:90));
xlabel('ʵ²¿ÐźÅ');
axis([0 100 -1.5 1.5]);
title('QPSK²åÖµºóÐòÁÐ');
subplot(2,1,2);
plot(insert_qpsk2(1:90),'yo');
axis([0 100 -1.5 1.5]);
hold on;
plot(insert_qpsk2(1:90));
xlabel('Ð鲿ÐźÅ');
axis([0 100 -1.5 1.5]);

%********ÉýÓàÏÒÂ˲¨Æ÷Â˲¨********
out_qpsk1=rise_cos(insert_qpsk1,N,8*N);
out_qpsk2=rise_cos(insert_qpsk2,N,8*N);
%»­³öÂ˲¨ºóµÄÐźÅ
figure(5);
subplot(2,1,1);
n=1:100;
plot(n,out_qpsk1(1:100),'.-r');
hold on;
m=25:104;
stem(m,insert_qpsk1(1:80),'o');
legend('Â˲¨Êä³öÐźÅ','ÊäÈëÐźÅ');
title('ͨ¹ýƽ·½¸ùÉýÓàÏÒÂ˲¨Æ÷Â˲¨µÃµ½QPSKʵ²¿Êä³öÐźţ¨10¸öÖÜÆÚ£©');
subplot(2,1,2);
plot(n,out_qpsk2(1:100),'.-r');
hold on;
stem(m,insert_qpsk2(1:80),'y');
legend('Â˲¨Êä³öÐźÅ','ÊäÈëÐźÅ');
title('ͨ¹ýƽ·½¸ùÉýÓàÏÒÂ˲¨Æ÷Â˲¨µÃµ½QPSKÐ鲿Êä³öÐźţ¨10¸öÖÜÆÚ£©');

%********Êä³öÐźÅÑÛͼ********
%Â˲¨ºóÁ½Â·Ðźźϲ¢£¬±í´ï³É¸´ÊýÐÎʽ
eyediagram(out_qpsk1,5*8);
title('QPSKʵ²¿ÑÛͼ');
eyediagram(out_qpsk2,5*8);
title('QPSKÐ鲿ÑÛͼ');

%********Êä³öÐźŹ¦ÂÊÆ×ÃܶÈ********
out_qpsk=out_qpsk1+i*out_qpsk2;
R_I=xcorr(out_qpsk);
power_qpsk=fft(R_I);
figure(8);
plot(10*log10(abs(power_qpsk(1:(length(power_qpsk)+1)/2)))-max(10*log10(abs(power_qpsk(1:(length(power_qpsk)+1)/2)))));
grid on;
xlabel('ƵÂÊ');
ylabel('dB');
title('QPSK¹¦ÂÊÆ×ÃܶÈ');