From 489aecaee146b4b39d6cf998c8d861430175d5bd Mon Sep 17 00:00:00 2001
From: Jens Ahrensfeld <jens@jayfield.org>
Date: Sat, 4 Apr 2015 08:34:11 +0000
Subject: [PATCH] - initial version

git-svn-id: http://moon:8086/svn/matlab/trunk@14 801c6759-fa7c-4059-a304-17956f83a07c
---
 ofdm/cfoml_eval.m  | 33 +++++++++++++++++++++++++++++++++
 ofdm/fdet_coarse.m | 11 +++++++++++
 2 files changed, 44 insertions(+)
 create mode 100644 ofdm/cfoml_eval.m
 create mode 100644 ofdm/fdet_coarse.m

diff --git a/ofdm/cfoml_eval.m b/ofdm/cfoml_eval.m
new file mode 100644
index 0000000..4756b88
--- /dev/null
+++ b/ofdm/cfoml_eval.m
@@ -0,0 +1,33 @@
+function cfoml_eval(x)
+
+N = 1024;       % number of subcarriers
+M = 103;        % number of subcarriers that carry information
+omega = 2*pi/N; % carrier spacing
+
+fa = 48000;
+fo = 0.0;
+
+x = 0.5*exp(i*2*pi.*(0:length(x)-1)'*fo/fa) .* x;
+
+U = exp(i*omega*(0:N-1)'*(0:N-1));
+
+W = U(:, 1:M);
+V = U(:, (M+1):N);
+
+phi = 0;
+dphi = pi/100;
+
+for j=1:100,
+phik(j) = phi;
+P = calcP(phi, N);
+phi = phi + dphi;
+
+S(j) = sum(abs(x'*P*U(:, M+1:N)).^2);
+end
+
+close all;
+
+plot(phik, real(S)); grid
+
+function P = calcP(phi, N)
+P = diag(exp(i*(0:N-1)*phi));
diff --git a/ofdm/fdet_coarse.m b/ofdm/fdet_coarse.m
new file mode 100644
index 0000000..28812ed
--- /dev/null
+++ b/ofdm/fdet_coarse.m
@@ -0,0 +1,11 @@
+function [f dmod] = fdet_coarse(x, N, fs, f_off_lo, df, f_off_hi)
+
+f_range = (f_off_lo:df:f_off_hi);
+
+for k=1:lge(f_range)
+    x_est = exp(-j*(2*pi*f_range(k)/fs*(0:N-1)' + 0));
+    dmod(k) = sum(x(1:N).*x_est);
+end;
+[v maxk] = max(abs(dmod));
+f = f_range(maxk);
+