- updated

git-svn-id: http://moon:8086/svn/matlab/trunk@154 801c6759-fa7c-4059-a304-17956f83a07c
2021-03-22 20:31:27 +00:00
parent b31f3e7435
commit e033d30500
1 changed files with 6 additions and 3 deletions
@@ -27,6 +27,9 @@ function iridium (name)
 [x, fs] = audioread(name);
 xc = (x(:,1) + i*x(:,2))';

+h_rc = fir_rrc(fs, 4/fs, 0.4, 65);
+xc = filter(h_rc, 1, xc);
+
 close all;
 N = length(x);

@@ -38,7 +41,7 @@ xc_cfo = xc .* lo;
 #xc_cfo = xc_cfo .* conj(xc_cfo);
 phi_cfo_uw = phi_unwrap(angle(xc_cfo));
 dphi_cfo = [0 diff(phi_cfo_uw)];
-foff = dphi_cfo*48000;
+foff = dphi_cfo*fs;
 found = find_preamble(dphi_cfo)

 alpha_mean = 0.1;
@@ -58,7 +61,7 @@ subplot(3,1,3)
 plot(1:N, dphi_cfo, "-o", 1:N, dphi_mean, 'r-'); legend('dphi'); grid;

 start=found(1)
-ende=start + 128
+ende=start + 400
 step=2

 figure
@@ -66,7 +69,7 @@ plot(real(xc_cfo(start:step:ende)), imag(xc_cfo(start:step:ende)), 'x'); grid;

 function found = find_preamble(phi)
 	thr = 0.5;
-	nsmp = 16;
+	nsmp = 120;
 	last = phi(1);
 	count = 0;
 	found = [];