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- removed fs from fdet_coarse

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- fdet_eval and fdet_wav use fdet
- ofdm_tx has additional parameter withData

git-svn-id: http://moon:8086/svn/matlab/trunk@20 801c6759-fa7c-4059-a304-17956f83a07c
This commit is contained in:
jens
2015-04-05 09:02:10 +00:00
parent e0bb654e70
commit 7e89f89dd5
3 changed files with 20 additions and 35 deletions
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ofdm/fdet_coarse.m
+5 -5
View File
@@ -1,11 +1,11 @@
function [f dmod] = fdet_coarse(x, N, fs, f_off_lo, df, f_off_hi)
function omega_coarse = fdet_coarse(x, N, omega_min, omega_step, omega_max)
f_range = (f_off_lo:df:f_off_hi);
omega_range = (omega_min:omega_step:omega_max);
for k=1:lge(f_range)
x_est = exp(-j*(2*pi*f_range(k)/fs*(0:N-1)' + 0));
for k=1:lge(omega_range)
x_est = exp(-j*(2*pi*omega_range(k)*(0:N-1)' + 0));
dmod(k) = sum(x(1:N).*x_est);
end;
[v maxk] = max(abs(dmod));
f = f_range(maxk);
omega_coarse = omega_range(maxk);
ofdm/fdet_eval.m
+11 -26
View File
@@ -6,44 +6,29 @@ fs = 48000;
N = 1024;
K = 40;
f_min = p(1);
f_max = p(2);
f_step = p(3);
omega_min = p(1)/fs;
omega_max = p(2)/fs;
omega_step = p(3)/fs;
% Generate signal
x_true = exp(j*(2*pi*f_true/fs*(0:K*N-1)'+phi_true)) + sqrt(10^(knoise_dB/10))*randn(K*N,1);
x = exp(j*(2*pi*f_true/fs*(0:K*N-1)'+ phi_true)) + sqrt(10^(knoise_dB/10))*randn(K*N,1);
% Initial guess
f_coarse = fdet_coarse(x_true, N, fs, f_min, f_step, f_max)
[omega, err, dmod, omega_coarse, omega_est] = fdet(x, N, omega_min, omega_step, omega_max);
phi_est = 0;
f_est = f_coarse;
for k=1:K
f(k) = f_est;
xp = x_true((k-1)*N+1:k*N);
x_est = exp(-j*(2*pi*f_est/fs*(0:N-1)' + phi_est));
dmod(k) = sum(xp.*x_est);
f_f = angle(dmod(k))/N*fs/(2*pi);
err(k) = f_f;
f_est = f_est + f_f;
dphi_est = 2*pi*mod(f_est/fs*N, 1);
phi_est = mod(phi_est + dphi_est, 2*pi);
end;
f_est = f_est
f_coarse = omega_coarse*fs
f_est = omega_est*fs
error_ppm = 1E6*(1-f_est/f_true)
close all;
subplot(4,1,1)
plot(1:lge(f), real(dmod)/N, 1:lge(f), imag(dmod)/N, 1:lge(f), abs(dmod)/N); grid; legend('Re', 'Im', 'abs()');
plot(1:lge(omega), real(dmod)/N, 1:lge(omega), imag(dmod)/N, 1:lge(omega), abs(dmod)/N); grid; legend('Re', 'Im', 'abs()');
subplot(4,1,2)
plot(1:lge(f), err, '-'); grid; legend('error');
plot(1:lge(omega), err, '-'); grid; legend('error');
subplot(4,1,3)
plot(1:lge(f), f); grid; legend('f');
plot(1:lge(omega), omega*fs); grid; legend('f');
subplot(4,1,4)
plot(1:lge(f), angle(dmod), '-*', 1:lge(f), diff(angle([0 dmod])), 'r-*'); grid; legend('phi', 'dphi');
plot(1:lge(omega), angle(dmod), '-*', 1:lge(omega), diff(angle([0 dmod])), 'r-*'); grid; legend('phi', 'dphi');
ofdm/ofdm_tx.m
+4 -4
View File
@@ -1,5 +1,5 @@
% function ofdm_tx(N_frames)
function [yv xv] = ofdm_tx(N_frames)
function [yv xv] = ofdm_tx(N_frames, withData)
close all;
@@ -7,7 +7,7 @@ WITH_RCWIN = 1;
WITH_FREQ_REF = 1;
WITH_TIME_REF = 0;
WITH_GAIN_REF = 0;
WITH_DATA = 0;
WITH_DATA = withData;
M_QAM = 4;
RCWIN_ROLLOFF = 0.1;
@@ -90,7 +90,7 @@ ofdm_params_drm(DRM_MODE_D) = struct('mode', 'MODE_D', 'nu', 112, 'ng', 88, 'nsp
ofdm_params_drm(DRM_MODE_E) = struct('mode', 'MODE_E', 'nu', 27, 'ng', 3, 'nspf', 40, 'W', W1024(DRM_MODE_E), 'Z', Z1024(DRM_MODE_E), 'Q', Q1024(DRM_MODE_E));
ofdm_params = ofdm_params_drm(DRM_MODE_B);
ofdm_spec_occ = ofdm_spec_occ_drm(DRM_MODE_B, SPEC_OCC_5k0);
ofdm_spec_occ = ofdm_spec_occ_drm(DRM_MODE_B, SPEC_OCC_10k);
ofdm_params_mode = ofdm_params.mode
ofdm_spec_occ_kmin = ofdm_spec_occ.kmin
@@ -128,7 +128,7 @@ for k=1:N_frames
if WITH_DATA == 1
data_i = c2i(N_fft, ofdm_spec_occ.kmin:1:ofdm_spec_occ.kmax);
sym = round(M_QAM*rand(1, length(data_i))+0.5);
X(data_i) = 0.20*qlut(sym);
X(data_i) = 0.10*qlut(sym);
end;
% X(c2i(N_fft,65)) = 0.20*qlut(round(M_qam*rand(1, 1)+0.5));